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HOW TO USE THIS MANUAL
BOATING SAFETY
BOATING EQUIPMENT (NOT REQUIRED
BUT RECOMMENDED)
SAFETY IN SERVICE
TROUBLESHOOTING
SHOP EQUIPMENT
TOOLS
FASTENERS, MEASUREMENT, AND CONVERSIONS
SPECIFICATIONS
UBLESHOOTING
POWERHEAD
POWERHEAD BREAK-IN
SPECIFICATIONS
GEARCASE
JET DRIVE GEARCASE
TRIMRILT SYSTEMS
MECHANICAL HYDRAULIC TILT ASSIST
TILLER HANDLE
MECHANICAL REMOTE CONTROLS
ELECTRONIC REMOTE CONTROLS
CONTROL CABLES
HAND REWIND STARTER
MASTER INDEX
P ures are vital to the safe, re1 s, as well as
the personal safety of those performing repairs. This manual outlines procedures for servicing and repairing
engines and drive systems using safe, effective methods. The procedures contain many NOTES, CAUTIONS
and WARNINGS which should be followed, along with standard procedures, to minimize the possibility of
personal injury or improper service which could damage the vehicle or compromise its safety.
It is important to note that repair procedures and techniques, tools and parts for servicing these engines, as
well as the skill and experience of the individual performing the work, vary widely. It is not possible to anticipate
all of the conceivable ways or conditions under which the engine may be serviced, or to provide cautions as to
all possible hazards that may result. Standard and accepted safety precautions and equipment should be used
during cutting, grinding, chiseling, prying, or any other process that can cause material removal or projectiles.
Some procedures require the use of tools specially designed for a specific task. Before substituting another
tool or procedure, you must be completely satisfied that neither your personal safety, nor the performance of the
vessel, will be endangered. All procedures covered in this manual requiring the use of special tools will be noted
at the beginning of the procedure by means of an
Additionally, any procedure requiring the use of an electronic tester or scan tool will be noted at the beginning
of the procedure by means of a
Although information in this manual is based on industry sources and is complete as possible at the time of
publication, the possibility exists that some manufacturers made later changes which could not be included here.
While striving for total accuracy, Seloc Publishing cannot assume responsibility for any errors, changes or
omissions that may occur in the compilation of this data. We must therefore warn you to follow instructions
carefully, using common sense. If you are uncertain of a procedure, seek help by inquiring with someone in your
area who is familiar with these motors before proceeding.
Part numbers listed in this reference are not recommendations by Seloc Publishing for any particular product
brand name, simply iterations of the manufacturer's suggestions. They are also references that can be used with
interchange manuals and aftermarket supplier catalogs to locate each brand supplier's discrete part number.
Special tools are recommended by the manufacturers to perform a specific job. Use has been kept to a
minimum, but, where absolutely necessary, they are referred to in the text by the part number of the
manufacturer if at all possible; and also noted at the beginning of each procedure with one of the following
symbols: OEM or DVOM.
The OEM symbol usually denotes the need for a unique tool purposely designed to accomplish a specific task,
it will also be used, less frequently, to notify the reader of the need for a tool that is not commonly found in the
average tool box.
symbol is used to denote the need for an electronic test tool like an ohmmeter, multi-meter or, on
certain later engines, a scan tool.
These tools can be purchased, under the appropriate part number, from your local dealer or regional
distributor, or an equivalent tool can be purchased locally from a tool supplier or parts outlet. Before substituting
any tool for the one recommended, read the SAFETY NOTICE at the top of this page.
Providing the correct mix of service and repair procedures is an endless battle for any publisher of "HOW-TO"
information. Users range from first time do-it yourselfers to professionally trained marine technicians, and
information important to one is frequently irrelevant to the other. The editors at Seloc Publishing strive to provide
accurate and articulate information on all facets of marine engine repair, from the simplest procedure to the most
complex. In doing this, we understand that certain procedures may be outside the capabilities of the average
DIYer. Conversely we are aware that many procedures are unnecessary for a trained technician.
In order to provide all oi our users, particularly the DIYers, with a feeling for the scope of a given procedure or
task before tackling it we have included a rating system denoting the suggested skill level needed when
performing a particular procedure. One of the following icons will be included at the beginning of most
procedures:
SY
These procedures are aimed primarily at the DIYer and can be classified, for
the most part, as basic maintenance procedures; battery, fluids, filters, plugs, etc. Although certainly valuable to
any experience level, they will generally be of little importance to a technician.
DERATE
.These procedures are suited for a DIYer with experience and a
working knowledge of mechanical procedures. Even an advanced DIYer or professional technician will
occasionally refer to these procedures. They will generally consist of component repair and service procedures,
adjustments and minor rebuilds.
CULT
These procedures are aimed at the advanced DIYer and professional
technician. They will deal with diagnostics, rebuilds and internal engineldrive components and will frequently
require special tools.
LED
.These procedures are aimed at highly skilled technicians and should not
be attempted without previous experience. They will usually consist of machine work, internal engine work and
gear case rebuilds.
Please remember one thing when considering the above ratings-they are a guide for judging the complexity
of a given procedure and are subjective in nature. Only you will know what your experience level is, and only
you will know when a procedure may be outside the realm of your capability. First time DIYer, or life-long marine
technician, we all approach repair and service differently so an easy procedure for one person may be a difficult
procedure for another. regardless of experience level. All skill level ratings are meant to be used as a guide only!
Use them to help make a judgement before undertaking a particular procedure, but by all means read through
the procedure first and make your own decision-after all, our mission at Seloc is to make boat maintenance
and repair easier for everyone whether you are changing the oil or rebuilding an engine. Enjoy beating!
No part of this publication may be reproduced, transmitted or stored in any form or by any means, electronic or
mechanical, including photocopy, recording, or by information storage or retrieval system, without prior written
permission from the publisher.
Seloc Publishing expresses appreciation to the following companies who supported the production of this
book:
Marine Mechanics Institute-Orlando, FL
Seloc Publishing would like to express thanks to the fine companies who participate in the production of all our
books:
Hand tools supplied by Craftsman are used during all phases of our vehicle teardown and photography.
*
Many of the fine specialty tools used in our procedures were provided courtesy of Lisle Corporation.
Much of our shop's electronic testing equipment was supplied by Universal Enterprises Inc. (UEI).
BASIC OPERATING PRINCIPLES .........1.13
2-STROKE MOTORS ..................1-13
4-STROKE MOTORS ..................1-15
COMBUSTION .......................1.1 6
BOATING EQUIPMENT (NOT REQUIRED
BUT RECOMMENDED) .................1.10
ANCHORS ..........................1-10
BAILING DEVICES ....................1-10
COMPASS ..........................1.10
FIRST AID KIT .......................1.10
OARIPADDLE........................1.10
TOOLS AND SPARE PARTS ............1.12
VHF-FM RADIO ......................140
BOATING SAFETY ......................1.4
COURTESY MARINE EXAMINATIONS ....1-10
REGULATIONS FOR YOUR BOAT ........1.4
REQUIRED SAFETY EQUIPMENT ........1.5
CHEMICALS ..........................1.17
CLEANERS ..........................1.18
LUBRICANTS& PENETRANTS..........1.17
SEALANTS ..........................1.17
COMPASS............................1.10
COMPASS PRECAUTIONS ............. 1.1 1
INSTALLATION.......................1-1 1
SELECTION .........................1.10
ELECTRONIC TOOLS ...................1-23
BATTERY CHARGERS .................1.23
BATTERY TESTERS ...................1.23
GAUGES ............................1.24
MULTI-METERS (DVOMS) .............. 1.23
FASTENERS. MEASUREMENTS
AND CONVERSIONS ...................1.26
BOLTS. NUTS & OTHER THREADED
RETAINERS .........................1-26
STANDARD & METRIC MEASUREMENTS 1-27
TORQUE ...........................1.27
HAND TOOLS .........................1.19
BREAKER BARS ......................1.20
HAMMERS ..........................1.22
PLIERS .............................1.21
SCREWDRIVERS..................... 1.21
SOCKET SETS .......................1.19
WRENCHES .........................1.21
HOW TO USE THIS MANUAL .............1.2
AVOIDING COMMON MISTAKES .........1.3
AVOIDING TROUBLE ...................1.2
CAN YOU DO IT? .....................1.2
DIRECTIONS & LOCATIONS ............1-2
MAINTENANCE OR REPAIR? ............1-2
PROFESSIONAL HELP ................. 1.3
PURCHASING PARTS ..................1.3
WHERE TO BEGIN .................... 1.2
MEASURING TOOLS ...................1.24
DEPTH GAUGES .....................1.26
DIAL INDICATORS .................... 1-25
MICROMETERS & CALIPERS ........... 1.24
TELESCOPING GAUGES ............... 1-26
REGULATIONS FOR YOUR BOAT ..........1.4
CAPACITY INFORMATION ...............1.4
CERTIFICATE OF COMPLIANCE .........1.5
DOCUMENTING OF VESSELS ...........1.4
HULL IDENTIFICATION NUMBER .........1.4
LENGTH OF BOATS .................... 1.4
NUMBERING OF VESSELS .............. 1.4
REGISTRATION OF BOATS ..............1.4
SALES AND TRANSFERS ............... 1.4
VENTILATION......................... 1.5
VENTILATION SYSTEMS ................ 1-5
REQUIRED SAFETY EQUIPMENT ..........1.5
FIRE EXTINGUISHERS ................. 1-6
PERSONAL FLOTATION DEVICES ........1.7
SOUND PRODUCING DEVICES ..........1-8
TYPES OF FIRES ......................1.5
VISUAL DISTRESS SIGNALS ............ 1-8
WARNING SYSTEM .................... 1.7
SAFETY IN SERVICE ...................1.12
DO'S ...............................1.12
DON'TS ............................1.12
SAFETY TOOLS ....................... 1.1 6
EYE AND EAR PROTECTION ........... 1.16
WORK CLOTHES ..................... 1.17
WORK GLOVES ......................1.16
SHOP EQUIPMENT ....................1.16
SAFETY TOOLS ......................1.16
SPECIFICATIONS......................1.27
CONVERSION FACTORS ..............1-27
METRIC BOLTS .
TYPICAL TORQUE VALUES ............1.28
U.S. STANDARD BOLTS .
TYPICAL TORQUE VALUES ............1.28
TOOLS...............................1-18
ELECTRONIC TOOLS .................1.23
HAND TOOLS ....................... 1.1 9
MEASURING TOOLS ..................1.24
OTHER COMMON TOOLS ............. 1.22
SPECIAL TOOLS ..................... 1.23
TROUBLESHOOTING ..................1.13
BASIC OPERATING PRINCIPLES ....... 1.1 3
This service is designed to be a handy reference guide to maintaining and
repairing your Suzuki Outboard. We strongly believe that regardless of how
many or how few year's experience you may have, there is something new
waiting here for you.
This service covers the topics that a factory service manual (designed for
factory trained mechanics) and a manufacturer owner's manual (designed
more by lawyers than boat owners these days) covers. It will take you
through the basics of maintaining and repairing your outboard, step-by-step,
to help you understand what the factory trained mechanics already know by
heart. By using the information in this service, any boat owner should be
able to make better informed decisions about what they need to do to
maintain and enjoy their outboard.
Even if you never plan on touching a wrench (and if so, we hope that we
can change your mind), this service will still help you understand what a
mechanic needs to do in order to maintain your engine.
If you are not the type who is prone to taking a wrench to something,
NEVER FEAR. The procedures provided here cover topics at a level virtually
anyone will be able to handle. And just the fact that you purchased this
service shows your interest in better understanding your outboard.
You may even find that maintaining your outboard yourself is preferable in
most cases. From a monetary standpoint, it could also be beneficial. The
money spent on hauling your boat to a marina and paying a tech to service
the engine could buy you fuel for a whole weekend of boating. And, if you
are really that unsure of your own mechanical abilities, at the very least you
should fully understand what a marine mechanic does to your boat. You may
decide that anything other than maintenance and adjustments should be
performed by a mechanic (and that's your call), but if so you should know
that every time you board your boat, you are placing faith in the mechanic's
work and trusting him or her with your well-being, and maybe your life.
It should also be noted that in most areas a factory-trained mechanic will
command a hefty hourly rate for off site service. If the tech comes to you this
hourly rate is often charged from the time they leave their shop to the time
that they return home. When service is performed at a boat yard, the clock
usually starts when they go out to get the boat and bring it into the shop and
doesn't end until it is tested and put back in the yard. The cost savings in
doing the job yourself might be readily apparent at this point.
Of course, if even you're already a seasoned Do-It-Yourselfer or a
Professional Technician, you'll find the procedures, specifications, special
tips as well as the schematics and illustrations helpful when tackling a new
job on a motor.
To help you decide if a task is within your skill level, procedures will
often be rated using a wrench symbol in the text. When present, the
number of wrenches designates how difficult we feel the procedure to
be on a 1-4 scale. For more details on the wrench icon rating system,
please refer to the information under Skill Levels at the beginning of
this service.
Before spending any money on parts, and before removing any nuts or
bolts, read through the entire procedure or topic. This will give you the
overall view or wnai tools and supplies will be required to perform the
procedure or what questions need to be answered before purchasing parts.
So read ahead and plan ahead. Each operation should be approached
logically and all procedures thoroughly understood before attempting any
work.
Some procedures in this service may require you to "label and disconnect
a
. ' a group of lines, hoses or wires. Don't be lulled into thinking you can
remember where everything goes -you won't. If you reconnect or install a
part incorrectly, the motor may operate poorly, if at all. If you hook up
electrical wiring incorrectly, you may instantly learn a very expensive lesson.
A piece of masking tape, for example, placed on a hose and another on
its fitting will allow you to assign your own label such as the letter "A", or a
short name. As long as you remember your own code, you can reconnect
the lines by matching letters or names. Do remember that tape will dissolve
when saturated in some fluids (especially cleaning solvents). If a component
is to be washed or cleaned, use another method of identification. A
permanent felt-tipped marker can be very handy for marking metal parts; but
remember that some solvents will remove permanent marker. A scribe can
be used to carefully etch a small mark in some metal parts, but be sure NOT
to do that on a gasket-making surface.
SAFETY is the most important thing to remember when performing
maintenance or repairs. Be sure to read the information on safety in this
service.
Proper maintenance is the key to long and trouble-free engine life, and
the work can yield its own rewards. A properly maintained engine performs
better than one that is neglected. As a conscientious boat owner, set aside a
Saturday morning, at least once a month, to perform a thorough check of
items that could cause problems. Keep your own personal log to jot down
which services you performed, how much the parts cost you, the date, and
the amount of hours on the engine at the time. Keep all receipts for parts
purchased, so that they may be referred to in case of related problems or to
determine operating expenses. As a do-it-yourselfer, these receipts are the
only proof you have that the required maintenance was performed. In the
event of a warranty problem (on new motors), these receipts can be
invaluable.
It's necessary to mention the difference between maintenance and repair.
Maintenance includes routine inspections, adjustments, and replacement of
parts that show signs of normal wear. Maintenance compensates for wear or
deterioration. Repair implies that something has broken or is not working. A
need for repair is often caused by lack of maintenance.
For example: draining and refilling the gearcase oil is TCTntenance
recommended by all manufacturers at specific intervals. Failure to do this
can allow internal corrosion or damage and impair the operation of the motor,
requiring expensive repairs. While no maintenance program can prevent
items from breaking or wearing out, a general rule can be stated:
MAINTENANCE IS CHEAPER THAN REPAIR.
See Figure 1
Two basic rules should be mentioned here. First, whenever the Port side
of the engine (or boat) is referred to, it is meant to specify the left side of the
engine when you are sitting at the helm. Conversely, the Starboard means
your right side. The Bow isthe front of the boat and the Stern or Aft is the
rear.
Fig. 1 Common terminology used for reference designation on
boats of all size. These terms are used throuah out the text
Most screws and bolts are removed by turning counterclockwise, and
tightened by turning clockwise. An easy way to remember this is: righty-
tighty; lefty-loosey. Corny, but effective. And if you are really dense (and we
have all been so at one time or another), buy a ratchet that is marked ON
and OFF (like [email protected] ratchets), or mark your own. This can be especially
helpful when you are bent over backwards, upside down or otherwise turned
around when working on a boat-mounted component.
Occasionally, there are some things when working on an outboard that
are bevond the caoabilities or tools of the averaae Do-It-Yourselfer (DIYer).
This shouldn't include most of the topics of this service, but you willhave to
be the judge. Some engines require special tools or a selection of special
parts, even for some basic maintenance tasks.
Talk to other boaters who use the same model of engine and speak with a
trusted marina to find if there is a particular system or component on your
engine that is difficult to maintain.
You will have to decide for yourself where basic maintenance ends and
where professional service should begin. Take your time and do your
research first (starting with the information contained within) and then make
your own decision. if you really don't feel comfortable with attempting a
procedure, DON'T DO IT. If you've gotten into something that may be over
your head, don't panic. Tuck your tail between your legs and call a marine
mechanic. Marinas and independent shops will be able to finish a job for
you. Your ego may be damaged, but your boat will be properly restored to its
full running order. So, as long as you approach jobs slowly and carefully, you
really have nothing to lose and everything to gain by doing it yourself.
On the other hand, even the most complicated repair is within the ability
of a person who takes their time and follows the steps of a procedure. A rock
climber doesn't run up the side of a cliff, helshe takes it one step at a time
and in the end, what looked difficult or impossible was conquerable. Worry
about one step at a time.
See Figures 2 and 3
When purchasing parts there are two things to consider. The first is quality
and the second is to be sure to get the correct part for your engine. To get
quality parts, always deal directly with a reputable retailer. To get the proper
parts always refer to the model number from the information tag on your
engine prior to calling the parts counter. An incorrect part can adversely
affect your engine performance and fuel economy, and will cost you more
money and aggravation in the end.
Just remember a tow back to shore will cost plenty. That charge is per
hour from the time the towboat leaves their home port, to the time they return
to their home port. Get the picture. . .$$$?
So whom should you call for parts? Well, there are many sources for the
parts you will need. Where you shop for parts will be determined by what
kind of parts you need, how much you want to pay, and the types of stores in
your neighborhood.
Your marina can supply you with many of the common parts you require.
Using a marina as your parts supplier may be handy because of location
(just walk right down the dock) or because the marina specializes in your
particular brand of engine. In addition, it is always a good idea to get to know
the marina staff (especially the marine mechanic).
The marine parts jobber, who is usually listed in the yellow pages or
whose name can be obtained from the marina, is another excellent source
for parts. In addition to supplying local marinas, they also do a sizeable
business in over-the-counter parts sales for the do-it-yourselfer.
Almost every boating community has one or more convenient marine
chain stores. These stores often offer the best retail prices and the
convenience of one-stop shopping for all your needs. Since they cater to the
do-it-yourselfer, these stores are almost always open weeknights, Saturdays,
and Sundays, when the jobbers are usually closed.
The lowest prices for parts are most often found in discount stores or the
auto department of mass merchandisers. Parts sold here are name and
private brand parts bought in huge quantities, so they can offer a competitive
price. Private brand parts are made by major manufacturers and sold to
large chains under a store label. And, of course, more and more large
automotive parts retailers are stocking basic marine supplies.
There are 3 common mistakes in mechanical work:
1. Following the incorrect order of assembly, disassembly or
adjustment. When taking something apart or putting it together, performing
steps in the wrong order usually just costs you extra time; however, it CAN
break something. Read the entire procedure before beginning disassembly.
Perform everything in the order in which the instructions say you should,
even if you can't immediately see a reason for it. When you're taking apart
something that is very intricate, you might want to draw a picture of how it
looks when assembled at one point in order to make sure you get everything
back in its proper position. When making adjustments, perform them in the
proper order; often, one adjustment affects another, and you cannot expect
satisfactory results unless each adjustment is made only when it cannot be
changed by subsequent adjustments.
B Digital cameras are handy. If you've got access to one, take pictures
of intricate assemblies during the disassembly process and refer to
them during assembly for tips on part orientation.
2. Over-torauina (or under-torauina). While it is more common for over-
torquing to cause damage, under-torquing may allow a fastener to vibrate
loose causing serious damage. Especially when dealing with plastic and
Fig. 3 Parts catalogs, giving application and part number
Fig. 2 By far the most important asset in purchasing parts is a information, are provided by manufacturers for most replacement
knowledgeable and enthusiastic parts person parts
aluminum parts, pay attention to torque specifications and utilize a torque
wrench in assembly. If a torque figure is not available, remember that if you
are using the right tool to perform the job, you will probably not have to strain
yourself to get a fastener tight enough. The pitch of most threads is so slight
that the tension you put on the wrench will be multiplied many times in actual
force on what you are tightening.
3. Cross-threading, This occurs when a part such as a bolt is screwed
into a nut or casting at the wrong angle and forced. Cross-threading is more
likely to occur if access is difficult. It helps to clean and lubricate fasteners,
then to start threading with the part to be installed positioned straight inward.
In 1971 Congress ordered the US. Coast Guard to improve recreational
boating safety. In response, the Coast Guard drew up a set of regulations.
Aside from these federal regulations, there are state and local laws you
must follow. These sometimes exceed the Coast Guard requirements. This
section discusses only the federal laws. State and local laws are available
from your local Coast Guard. As with other laws, "Ignorance of the boating
laws is no excuse." The rules fall into two groups: regulations for your boat
and required safety equipment on your boat.
Most boats on waters within Federal jurisdiction must be registered or
documented. These waters are those that provide a means of transportation
between two or more states or to the sea. They also include the territorial
waters of the United States.
DOCUMENTING OF VESSELS
A vessel of five or more net tons may be documented as a yacht. In this
process, papers are issued by the US. Coast Guard as they are for large
ships. Documentation is a form of national registration. The boat must be
used solely for pleasure. Its owner must be a citizen of the U.S., a
partnership of U.S. citizens, or a corporation controlled by US. citizens. The
captain and other officers must also be US. citizens. The crew need not be.
If you document your yacht, you have the legal authority to fly the yacht
ensign. You also may record bills of sale, mortgages, and other papers of
title with federal authorities. Doing so gives legal notice that such instruments
exist. Documentation also permits preferred status for mortgages. This gives
you additional security, and it aids in financing and transferoftitle. You must
carry the original documentation papers aboard your vessel. Copies will not
suffice.
REGISTRATION OF BOATS
If your boat is not documented, registration in the state of its principal use
is probably required. If you use it mainly on an ocean, a gulf, or other similar
water, register it in the state where you moor it.
If you use your boat solely for racing, it may be exempt from the
requirement in your state. Some states may also exclude dinghies, while
others require registration of documented vessels and non-power driven
boats.
All states, except Alaska, register boats. In Alaska, theAJ.S. Coast Guard
issues the registration numbers. If you move your vessel to a new state of
principal use, a valid registration certificate is good for 60 days. You must
have the registration certificate (certificate of number) aboard your vessel
when it is in use. A copy will not suffice. You may be cited if you do not have
the original on board.
NUMBERING OF VESSELS
A registration number is on your registration certificate. You must paint or
permanently attach this number to both sides of the forward half of your
boat. Do not display any other number there.
The registration number must be clearly visible. It must not be placed on
the obscured underside of a flared bow. If you can't place the number on the
bow, place it on the forward half of the hull. If that doesn't work, put it on the
superstructure. Put the number for an inflatable boat on a bracket or fixture.
Then, firmly attach it to the forward half of the boat. The letters and numbers
must be plain block characters and must read from left to right. Use a space
Always start a fastener, etc. with your fingers. If you encounter resistance,
unscrew the part and start over again at a different angle until it can be
inserted and turned several times without much effort. Keep in mind that
some parts may have tapered threads, so that gentle turning will
automatically bring the part you're threading to the proper angle, but only if
you don't force it or resist a change in angle. Don't put a wrench on the part
until it has been tightened a couple of turns by hand. If you suddenly
encounter resistance, and the part has not seated fully, don't force it. Pull it
back out to make sure it's clean and threading properly.
or a hyphen to separate the prefix and suffix letters from the numerals. The
color of the characters must contrast with that of the background, and they
must be at least three inches high.
In some states your registration is good for only one year. In others, it is
good for as long as three years. Renew your registration before it expires. At
that time you will receive a new decal or decals. Place them as required by
state law. You should remove old decals before putting on the new ones.
Some states require that you show only the current decal or decals. If your
vessel is moored, it must have a current decal even if it is not in use.
If your vessel is lost, destroyed, abandoned, stolen, or transferred, you
must inform the issuing authority. If you lose your certificate of number or
your address changes, notify the issuing authority as soon as possible.
SALES AND TRANSFERS
Your registration number is not transferable to another boat. The number
stays with the boat unless its state of principal use is changed.
HULL IDENTIFICATION NUMBER
A Hull Identification Number (HIN) is like the Vehicle Identification Number
(VIN) on your car. Boats built between November 1, 1972 and July 31, 1984
have old format HINs. Since August 1,1984 a new format has been used.
Your boat's HIN must appear in two places. If it has a transom, the
primary number is on its starboard side within two inches of its top. If it does
not have a transom or if it was not practical to use the transom, the number
is on the starboard side. In this case, it must be within one foot of the stern
and within two inches of the top of the hull side. On pontoon boats, it is on
the aft crossbeam within one foot of the starboard hull attachment. Your boat
also has a duplicate number in an unexposed location. This is on the boat's
interior or under a fitting or item of hardware.
LENGTH OF BOATS
For some purposes, boats are classed by length. Required equipment, for
example, differs with boat size. Manufacturers may measure a boat's length
in several ways. Officially, though, your boat is measured along a straight
line from its bow to its stem. This line is parallel to its keel.
The length does not include bowsprits, boomkins, or pulpits. Nor does it
include rudders, brackets, outboard motors, outdrives, diving platforms, or
other attachments.
CAPACITY INFORMATION
@ See Figure 4
Manufacturers must put capacity plates on most recreational boats less
than 20 feet long. sailboats, canoes; kayaks, and inflatable boats are usually
exemot. Outboard boats must disolav the maximum permitted horseuower of
their engines. The plates must also show the allowable maximum weights of
the people on board. And they must show the allowable maximum combined
weights of people, engine(s), and gear. Inboards and stem drives need not
show the weight of their engines on their capacity plates. The capacity plate
must appear where it is clearly visible to the operator when underway. This
information serves to remind you of the capacity of your boat under normal
circumstances. You should ask yourself, "Is my boat loaded above its
recommended capacity" and, "Is my boat overloaded for the present sea and
wind conditions?" If you are stopped by a legal authority, you may be cited if
you are overloaded.
Fig. 4 A U.S. Coast Guard certification plate indicates the amount
of occupants and gear appropriate for safe operation of the vessel
CERTIFICATE OF COMPLIANCE
See Figure 4
Manufacturers are required to put compliance plates on motorboats
greater than 20 feet in length. The plates must say, "This boat," or "This
equipment complies with the U. S. Coast Guard Safety Standards in effect
on the date of certification." Letters and numbers can be no less than one
eighth of an inch high. At the manufacturer's option, the capacity and
compliance plates may be combined.
VENTILATION
A cup of gasoline spilled in the bilge has the potential explosive power of
15 sticks of dynamite. This statement, commonly quoted over 20 years ago,
may be an exaggeration; however, it illustrates a fact. Gasoline fumes in the
bilge of a boat are highly explosive and a serious danger. They are heavier
than air and will stay in the bilge until they are vented out.
Because of this danger, Coast Guard regulations require ventilation on
many powerboats. There are several ways to supply fresh air to engine and
gasoline tank compartments and to remove dangerous vapors. Whatever the
choice, it must meet Coast Guard standards.
B The following is not intended to be a complete discussion of the
regulations. It is limited to the majority of recreational vessels. Contact
your local Coast Guard office for further information.
General Precautions
Ventilation systems will not remove raw gasoline that leaks from tanks or
fuel lines. If you smell gasoline fumes, you need immediate repairs. The best
device for sensing gasoline fumes is your nose. Use it! If you smell gasoline
in a bilge, engine compartment, or elsewhere, don't start your engine. The
smaller the compartment, the less gasoline it takes to make an explosive
mixture.
Ventilation for Open Boats
In open boats, gasoline vapors are dispersed by the air that moves
through them. So they are exempt from ventilation requirements.
To be "open," a boat must meet certain conditions. Engine and fuel tank
compartments and long narrow compartments that join them must be open
to the atmosphere." This means they must have at least 15 square inches of
open area for each cubic foot of net compartment volume. The op- on area
must be in direct contact with the atmosphere. There must also be no long,
unventilated spaces open to engine and fuel tank compartments into which
flames could extend.
Ventilation for All Other Boats
Powered and natural ventilation are required in an enclosed compartment
with a permanently installed gasoline engine that has a cranking motor. A
compartment is exempt if its engine is open to the atmosphere. Diesel
powered boats are also exempt.
VENTILATION SYSTEMS
There are two types of ventilation systems. One is "natural ventilation." In
it, air circulates through closed spaces due to the boat's motion. The other
type is "powered ventilation." In it, air is circulated by a motor-driven fan or
fans.
Natural Ventilation System Requirements
A natural ventilation system has an air supply from outside the boat. The
air supply may also be from a ventilated compartment or a compartment
open to the atmosphere. Intake openings are required. In addition, intake
ducts may be required to direct the air to appropriate compartments.
The system must also have an exhaust duct that starts in the lower third
of the compartment. The exhaust opening must be into another ventilated
compartment or into the atmosphere. Each supply opening and supply duct,
if there is one, must be above the usual level of water in the bilge. Exhaust
openings and ducts must also be above the bilge water. Openings and ducts
must be at least three square inches in area or two inches in diameter.
Openings should be placed so exhaust gasses do not enter the fresh air
intake. Exhaust fumes must not enter cabins or other enclosed, non-
ventilated spaces. The carbon monoxide gas in them is deadly.
Intake and exhaust openings must be covered by cowls or similar
devices. These registers keep out rain water and water from breaking seas.
Most often, intake registers face forward and exhaust openings aft. This aids
the flow of air when the boat is moving or at anchor since most boats face
into the wind when properly anchored.
Power Ventilation System Requirements
See Figure 5
Powered ventilation systems must meet the standards of a natural
system, but in addition, they must also have one or more exhaust blowers.
The blower duct can serve as the exhaust duct for natural ventilation if fan
blades do not obstruct the air flow when not powered. Openings in engine
compartment, for carburetion are in addition to ventilation system
requirements.
Coast Guard regulations require that your boat have certain equipment
aboard. These requirements are minimums. Exceed them whenever you
can.
TYPES OF FIRES
There are four common classes of fires:
* Class A -fires are of ordinary combustible materials such as paper or
wood.
*
Class B -fires involve gasoline, oil and grease.
Class C -fires are electrical.
*
Class D -fires involve ferrous metals
One of the greatest risks to boaters is fire. This is why it is so important to
carry the correct number and type of extinguishers onboard.
!
Fig. 5 Typical blower and duct system to vent fumes from the
engine compartment
The best fire extinguisher for most boats is a Class B extinguisher. Never
use water on Class B or Class C fires, as water spreads these types of fires.
Additionally, you should never use water on a Class C fire as it may cause
you to be electrocuted.
FIRE EXTINGUISHERS
e See Figure 6
If your boat meets one or more of the following conditions, you must have
at least one fire extinguisher aboard. The conditions are:
*
Inboard or stern drive engines
Closed compartments under seats where portable fuel tanks can be
stored
Double bottoms not sealed together or not completely filled with
flotation materials
Closed living spaces
* Closed stowage compartments in which combustible or flammable
materials are stored
*
Permanently installed fuel tanks
*
Boat is 26 feet or more in length.
Contents of Extinguishers
Fire extinguishers use a variety of materials. Those used on boats usually
contain dry chemicals, Halon, or Carbon Dioxide (C02). Dry chemical
extinguishers contain chemical powders such as Sodium Bicarbonate -
baking soda.
Carbon dioxide is a colorless and odorless gas when released from an
extinguisher. It is not poisonous but caution must be used in entering
comoartments filled with it. It will not su~~ort
life and keeos oxvaen from
reaching your lungs. A firekilling concentration of carbon ~ioxide can be
lethal. If you are in a compartment with a high concentration of C02, you will
have no difficulty breathing. But the air does not contain enough oxygen to
support life. Unconsciousness or death can result.
Halon Extinguishers
Some fire extinguishers and "built-in" or "fixed automatic fire
extinguishing systems contain a gas called Halon. Like carbon dioxide it is
colorless and odorless and will not suooort life. Some Halons may be toxic if
. .
inhaled.
To be accepted by the Coast Guard, a fixed Halon system must have an
indicator light at the vessel's helm. A green light shows the system is ready.
Red means it is being discharged or has been discharged. Warning horns
are available to let you know the system has been activated. If your fixed
Halon system discharges, ventilate the space thoroughly before you enter it.
There are no residues from Halon but it will not support life.
Fig.6 An approved fire extinguisher should be mounted close to
the operator for emeraencv use
Although Halon has excellent fire fighting properties; it is thought to
deplete the earth's ozone layer and has not been manufactured since
January 1, 1994. Halon extinguishers can be refilled from existing stocks of
the gas until they are used up, but high federal excise taxes are being
charged for the service. If you discontinue using your Halon extinguisher,
take it to a recovery station rather than releasing the gas into the
atmosphere. Compounds such as FE 241, designed to replace Halon, are
now available.
Fire Extinguisher Approval
Fire extinguishers must be Coast Guard approved. Look for the approval
number on the nameplate. Approved extinguishers have the following on
their labels: "Marine Type USCG Approved, Size. . .,Type. .., 162.2081,'' etc.
In addition, to be acceptable by the Coast Guard, an extinguisher must be in
serviceable condition and mounted in its bracket. An extinguisher not
properly mounted in its bracket will not be considered serviceable during a
Coast Guard inspection.
Care and Treatment
Make certain your extinguishers are in their stowage brackets and are not
damaged. Replace cracked or broken hoses. Nozzles should be free of
obstructions. Sometimes, wasps and other insects nest inside nozzles and
make them inoperable. Check your extinguishers frequently. If they have
pressure gauges, is the pressure within acceptable limits? Do the locking
pins and sealing wires show they have not been used since recharging?
Don't try an extinguisher to test it. Its valves will not reseat properly and
the remaining gas will leak out. When this happens, the extinguisher is
useless.
Weigh and tag carbon dioxide and Halon extinguishers twice a year. If
their weight loss exceeds 10 percent of the weight of the charge, recharge
them. Check to see that they have not been used. They should have been
inspected by a qualified person within the past six months, and they should
have tags showing all inspection and service dates. The problem is that they
can be partially discharged while appearing to be fully charged.
Some Halon extinguishers have pressure gauges the same as dry
chemical extinguishers. Don't rely too heavily on the gauge. The extinguisher
can be partially discharged and still show a good gauge reading. Weighing a
Halon extinguisher is the only accurate way to assess its contents.
If your dry chemical extinguisher has a pressure indicator, check it
frequently. Check the nozzle to see if there is powder in it. If there is,
recharge it. Occasionally invert your dry chemical extinguisher and hit the
base with the palm of your hand. The chemical in these extinguishers packs
and cakes due to the boat's vibration and pounding. There is a difference of
opinion about whether hitting the base helps, but it can't hurt. It is known that
caking of the chemical powder is a major cause of failure of dry chemical
extinguishers. Carry spares in excess of the minimum requirement. If you
have guests aboard, make certain they know where the extinguishers are
and how to use them.
Using a Fire Extinguisher
A fire extinguisher usually has a device to keep it from being discharged
accidentally. This is a metal or plastic pin or loop. If you need to use your
extinguisher, take it from its bracket. Remove the pin or the loop and point
the nozzle at the base of the flames. Now, squeeze the handle, and
discharge the extinguisher's contents while sweeping from side to side.
Recharge a used extinguisher as soon as possible.
If you are using a Halon or carbon dioxide extinguisher, keep your hands
away from the discharge. The rapidly expanding gas will freeze them. If your
fire extinguisher has a horn, hold it by its handle.
Legal Requirements for Extinguishers
You must carry fire extinguishers as defined by Coast Guard regulations.
They must be firmly mounted in their brackets and immediately accessible.
A motorboat less than 26 feet long must have at least one approved
hand-portable, Type B-1 extinguisher. If the boat has an approved fixed fire
extinguishing system, you are not required to have the Type B-1
extinguisher. Also, if your boat is less than 26 feet long, is propelled by an
outboard motor, or motors, and does not have any of the first six conditions
described at the beginning of this section, it is not required to have an
extinguisher. Even so, it's a good idea to have one, especially if a nearby
boat catches fire. or if a fire occurs at a fuel dock.
A motorboat 26 feet to less than 40 feet long, must have at least two Type
B-1 aooroved hand-oortable extinauishers. It can, instead, have at least one
coast Guard approved Type B-2. If you have an approved fire extinguishing
system, only one Type B-1 is required.
A motorboat 40 to 65 feet long must have at least three Type B-1
aooroved oortable extinauishers. It mav have. instead, at least one Tvoe B-1
a ~~~e B-2. If thereis an approved fixedfire extinguishing system, two
Type B-1 or one Type B-2 is required.
WARNING SYSTEM
Various devices are available to alert you to danger. These include fire,
smoke, gasoline fumes, and carbon monoxide detectors. If your boat has a
galley, it should have a smoke detector. Where possible, use wired
detectors. Household batteries often corrode rapidly on a boat.
There are many ways in which carbon monoxide (a by-product of the
combustion that occurs in an engine) can enter your boat. You can't see,
smell, or taste carbon monoxide gas, but it is lethal. As little as one part in
10,000 parts of air can bring on a headache. The symptoms of carbon
monoxide poisoning -headaches, dizziness, and nausea -are like
seasickness. By the time you realize what is happening to you, it may be too
late to take action. If you have enclosed living spaces on your boat, protect
yourself with a detector.
PERSONAL FLOTATION DEVICES
Personal Flotation Devices (PFDs) are commonly called life preservers or
life jackets. You can get them in a variety of types and sizes. They vary with
their intended uses. To be acceptable, PFDs must be Coast Guard
approved.
Type IPFDs
A Type Ilife jacket is also called an offshore life jacket. Type I life jackets
will turn most unconscious people from facedown to a vertical or slightly
backward position. The adult size gives a minimum of 22 pounds of
buoyancy. The child size has at least 11 pounds. Type Ijackets provide more
protection to their wearers than any other type of life jacket. Type Ilife
jackets are bulkier and less comfortable than other types. Furthermore, there
are only two sizes, one for children and one for adults.
Type Ilife jackets will keep their wearers afloat for extended periods in
rough water. They are recommended for offshore cruising where a delayed
rescue is probable.
Type 11 PFDs
+ See Figure 7
AType IIlife jacket is also called a near-shore buoyant vest. It is an
approved, wearable device. Type IIlife jackets will turn some unconscious
people from facedown to vertical or slightly backward positions. The adult
size gives at least 15.5 pounds of buoyancy. The medium child size has a
minimum of 11 pounds. And the small child and infant sizes give seven
pounds. AType II life jacket is more comfortable than a Type I but it does not
have as much buoyancy. It is not recommended for long hours in rough
water. Because of this, Type 11s are recommended for inshore and inland
cruising on calm water. Use them only where there is a good chance of fast
rescue.
Type IllPFDs
Type Illlife jackets or marine buoyant devices are also known as flotation
aids. Like Type \Is, they are designed for calm inland or close offshore water
where there is a good chance of fast rescue. Their minimum buoyancy is
15.5 pounds. They will not turn their wearers face up.
Type Ill devices are usually worn where freedom of movement is
necessary. Thus, they are used for water skiing, small boat sailing, and
fishing among other activities. They are available as vests and flotation
coats. Flotation coats are useful in cold weather. Type Ills come in many
sizes from small child through large adult.
Life jackets come in a variety of colors and patterns -red, blue, green,
camouflage, and cartoon characters. From purely a safety standpoint, the
best color is bright orange. It is easier to see in the water, especially if the
water is rough.
Type IV PFDs
+ See Figure 8 and 9
Type IV ring life buoys, buoyant cushions and horseshoe buoys are Coast
Guard approved devices called throwables. They are made to be thrown to
people in the water, and should not be worn. Type IV cushions are often
used as seat cushions. But, keep in mind that cushions are hard to hold onto
in the water, thus, they do not afford as much protection as wearable life
jackets.
The straps on buoyant cushions are for you to hold onto either in the
water or when throwing them, they are NOT for your arms. A cushion should
never be worn on your back, as it will turn you face down in the water.
Type IV throwables are not designed as personal flotation devices for
unconscious people, non-swimmers, or children. Use them only in
emergencies. They should not be used for, long periods in rough water.
Ring life buoys come in 18, 20, 24, and 30 in. diameter sizes. They
usually have grab lines, but you will need to attach about 60 feet of
polypropylene line to the grab rope to aid in retrieving someone in the water.
If you throw a ring, be careful not to hit the person. Ring buoys can knock
people unconscious
Type V PFDs
Type V PFDs are of two kinds, special use devices and hybrids. Special
use devices include boardsailing vests, deck suits, work vests, and others.
They are approved only for the special uses or conditions indicated on their
labels. Each is designed and intended for the particular application shown on
its label. They do not meet legal requirements for general use aboard
recreational boats.
Hybrid life jackets are inflatable devices with some built-in buoyancy
provided by plastic foam or kapok. They can be inflated orally or by cylinders
of compressed gas to give additional buoyancy. In some hybrids the gas is
released manually. In others it is released automatically when the life jacket
is immersed in water.
The inherent buoyancy of a hybrid may be insufficient to float a person
unless it is inflated. The only way to find this out is for the user So try it in the
water. Because of its limited buoyancy when deflated, a hybrid is
recommended for use by a non-swimmer only if it is worn with enough
inflation to float the wearer.
If they are to count against the legal requirement for the number of life
jackets you must carry, hybrids manufactured before February 8, 1995 must
be worn whenever a boat is underway and the wearer must not go below
decks or in an enclosed space. To find out if your Type V hybrid must be
worn to satisfy the legal requirement, read its label. If its use is restricted it
will say, "REQUIRED TO BE WORN in capital letters.
Hybrids cost more than other life jackets, but this factor must be weighed
against the fact that they are more comfortable than Types I, IIor Illlife
jackets. Because of their greater comfort, their owners are more likely to
wear them than are the owners of Type I, IIor Illlife jackets.
The Coast Guard has determined that improved, less costly hybrids can
save lives since they will be bought and used more frequently. For these
reasons, a new federal regulation was adopted effective February 8, 1995.
The regulation increases both the deflated and inflated buoyancys of hybrids,
makes them available in a greater variety of sizes and types, and reduces
their costs by reducing production costs.
Even though it may not be required, the wearing of a hybrid or a life jacket
is encouraaed whenever a vessel is underway. Like life jackets, hybrids are
now available in three types. To meet legal requirements, a Type ihybrid can
be substituted for a Tvoe I life Jacket. Similariv Tvoe 11 and Illhvbrids can be
substituted for Type liand ~~pe Ihybrid,when inflated,
Illlife jackets. ~'t~~e
will turn most unconscious people from facedown to vertical or slightly
backward positions just like a Type Ilife jacket. Type IIand Illhybrids
function like Type IIand Ill life jackets. If you purchase a new hybrid, it
should have an owner's manual attached that describes its life jacket type
and its deflated and inflated buoyancys. It warns you that it may have to be
inflated to float you. The manual also tells you how to don the life jacket and
how to inflate it. It also tells you how to change its inflation mechanism,
recommended testing exercises, and inspection or maintenance procedures.
The manual also tells you why you need a life jacket and why you should
wear it. A new hybrid must be packaged with at least three gas cartridges.
One of these may already be loaded into the inflation mechanism. Likewise,
if it has an automatic inflation mechanism, it must be packaged with at least
three of these water sensitive elements. One of these elements may be
installed.
Legal Requirements
A Coast Guard approved life jacket must show the manufacturer's name
and approval number. Most are marked as Type I,11, Ill,IV or V. All of the
newer hybrids are marked for type.
You are required to carry at least one wearable life jacket or hybrid for
each person on board your recreational vessel. If your vessel is 16 feet or
more in length and is not a canoe or a kayak, you must also have at least
one Type IV on board. These requirements apply to all recreational vessels
that are propelled or controlled by machinery, sails, oars, paddles, poles, or
another vessel. Sailboards are not required to carry life jackets.
You can substitute an older Type V hybrid for any required Type I,IIor Ill
life jacket provided:
1. Its approval label shows it is approved for the activity the vessel is
engaged in
2. It's approved as a substitute for a life jacket of the type required on
the vessel
3. It's used as required on the labels
and
4. It's used in accordance with any requirements in its owner's manual
(if the approval label makes reference to such a manual.)
A water skier being towed is considered to be on board the vessel when
judging compliance with legal requirements.
You are required to keep your Type I, II or Illlife jackets or equivalent
hybrids readily accessible, which means you must be able to reach out and
get them when needed. All life jackets must be in good, serviceable
condition.
General Considerations
The proper use of a life jacket requires the wearer to know how it will
perform. You can gain this knowledge only through experience. Each person
on your boat should be assigned a life jacket. Next, it should be fitted to the
person who will wear it. Only then can you be sure that it will be ready for
use in an emergency. This advice is good even if the water is calm, and you
intend to boat near shore.
Boats can sink fast. There may be no time to look around for a life jacket.
Fitting one on you in the water is almost impossible. Most drownings occur in
inland waters within a few feet of safety. Most victims had life jackets, but
they weren't wearing them.
Keeping life jackets in the plastic covers they came wrapped in, and in a
cabin, assure that they will stay clean and unfaded. But this is no way to
keep them when you are on the water. When you need a life jacket it must
be readily accessible and adjusted to fit you. You can't spend time hunting
for it or learning how to fit it.
There is no substitute for the experience of entering the water while
wearing a life jacket. Children, especially, need practice. If possible, give
your guests this experience. Tell them they should keep their arms to their
sides when jumping in to keep the life jacket from riding up. Let them jump in
and see how the life jacket responds. Is it adjusted so it does not ride up? Is
it the proper size? Are all straps snug? Are children's life jackets the right
sizes for them? Are they adjusted properly? If a child's life jacket fits
correctly, you can lift the child by the jacket's shoulder straps and the child's
chin and ears will not slip through. Non-swimmers, children, handicapped
persons, elderly persons and even pets should always wear life jackets when
they are aboard. Many states require that everyone aboard wear them in
hazardous waters.
Inspect your lifesaving equipment from time to time. Leave any
questionable or unsatisfactory equipment on shore. An emergency is no time
for you to conduct an inspection.
Indelibly mark your life jackets with your vessel's name, number, and
calling port. This can be important in a search and rescue effort. It could help
concentrate effort where it will do the most good.
Care of Life Jackets
Given reasonable care, life jackets last many years. Thoroughly dry them
before putting them away. Stow them in dry, well-ventilated places. Avoid the
bottoms of lockers and deck storage boxes where moisture may collect. Air
and dry them frequently.
Life jackets should not be tossed about or used as fenders or cushions.
Many contain kapok or fibrous glass material enclosed in plastic bags. The
bags can rupture and are then unserviceable. Squeeze your life jacket
gently. Does air leak out? If so, water can leak in and it will no longer be safe
to use. Cut it up so no one will use it, and throw it away. The covers of some
life jackets are made of nylon or polyester. These materials are plastics. Like
many plastics, they break down after extended exposure to the ultraviolet
light in sunlight. This process may be more rapid when the materials are
dyed with bright dyes such as "neon" shades.
Ripped and badly faded fabrics are clues that the covering of your life
jacket is deteriorating. A simple test is to pinch the fabric between your
thumbs and forefingers. Now try to tear the fabric. If it can be torn, it should
definitely be destroyed and discarded. Compare the colors in protected
places to those exposed to the sun. If the colors have faded, the materials
have been weakened. A life jacket covered in fabric should ordinarily last
several boating seasons with normal use. A life jacket used every day in
direct sunlight should probably be replaced more often.
SOUND PRODUCING DEVICES
All boats are required to carry some means of making an efficient sound
signal. Devices for making the whistle or horn noises required by the
Navigation Rules must be capable of a four-second blast. The blast should
be audible for at least one-half mile. Athletic whistles are not acceptable on
boats 12 meters or longer. Use caution with athletic whistles. When wet,
some of them come apart and loose their "pea." When this happens, they
are useless.
If your vessel is 12 meters long and less than 20 meters, you must have a
power whistle (or power horn) and a bell on board. The bell must be in
operating condition and have a minimum diameter of at least 200mm (7.9 in.)
at its mouth.
VISUAL DISTRESS SIGNALS
See Figure 10
Visual Distress Signals (VDS) attract attention to your vessel if you need
help. They also help to guide searchers in search and rescue situations. Be
sure you have the right types, and learn how to use them properly.
It is illegal to fire flares improperly. In addition, they cost the Coast Guard
and its Auxiliary many wasted hours in fruitless searches. If you signal a
distress with flares and then someone helps you, please let the Coast Guard
or the appropriate Search And Rescue (SAR) Agency know so the distress
report will be canceled.
Recreational boats less than 16 feet long must carry visual distress
signals on coastal waters at night. Coastal waters are:
e The ocean (territorial sea)
* The Great Lakes
@
Bays or sounds that empty into oceans
Rivers over two miles across at their mouths upstream to where they
narrow to two miles.
Recreational boats 16 feet or longer must carry VDS at all times on
coastal waters. The same requirement applies to boats carrying six or fewer
passengers for hire. Open sailboats less than 26 feet long without engines
are exempt in the daytime as are manually propelled boats. Also exempt are
boats in organized races, regattas, parades, etc. Boats owned in the United
States and operating on the high seas must be equipped with VDS.
A wide variety of signaling devices meet Coast Guard regulations. For
pyrotechnic devices, a minimum of three must be carried. Any combination
can be carried as long as it adds up to at least three signals for day use and
at least three signals for night use. Three daylnight signals meet both
requirements. if possible, carry more than the legal requirement.
The American flag flying upside down is a commonly recognized
distress signal. It is not recognized In the Coast Guard regulations,
though. In an emergency, your efforts would probably be better used In
more effective signaling methods.
Types of VDS
VDS are divided into two groups; daytime and nighttime use. Each of
these groups is subdivided into pyrotechnic and non-pyrotechnic devices.
Daytime Non-Pyrotechnic Signals
A bright orange flag with a black square over a black circle is the simplest
VDS. It is usable, of course, only in daylight. It has the advantage of being a
continuous signal. A mirror can be used to good advantage on sunny days. It
can attract the attention of other boaters and of aircraft from great distances.
Mirrors are available with holes in their centers to aid in "aiming." In the
absence of a mirror, any shiny object can be used. When another boat is in
sight, an effective VDS is to extend your arms from your sides and move
them up and down. Do it slowly. If you do it too fast the other people may
think you are just being friendly. This simple gesture is seldom
misunderstood, and requires no equipment.
Daytime Pyrotechnic Devices
Orange smoke is a useful daytime signal. Hand-held or floating smoke
flares are very effective in attracting attention from aircraft. Smoke flares
don't last long, and are not very effective in high wind or poor visibility. As
with other pyrotechnic devices, use them only when you know there is a
possibility that someone will see the display.
To be usable, smoke flares must be kept dry. Keep them in airtight
containers and store them in dry places. If the "striker" is damp, dry it out
before trying to ignite the device. Some pyrotechnic devices require a
forceful "strike" to ignite them.
All hand-held pyrotechnic devices may produce hot ashes or slag when
burning. Hold them over the side of your boat in such a way that they do not
burn your hand or drip into your boat.
Nighttime Non-Pyrotechnic Signals
An electric distress light is available. This light automatically flashes the
international morse code SOS distress signal (Â¥--***). Flashed four to six
times a minute, it is an unmistakable distress signal. It must show that it is
approved by the Coast Guard. Be sure the batteries are fresh. Dated
batteries give assurance that they are current.
Under the Inland Navigation Rules, a high intensity white light flashing 50-
70 times per minute is a distress signal. Therefore, use strobe lights on
inland waters only for distress signals.
Nighttime Pyrotechnic Devices
See Figure 11
Aerial and hand-held flares can be used at night or in the daytime.
Obviously, they are more effective at night.
Currently, the serviceable life of a pyrotechnic device is rated at 42
months from its date of manufacture. Pyrotechnic devices are expensive.
Look at their dates before you buy them. Buy them with as much time
remaining as possible.
Like smoke flares, aerial and hand-held flares may fail to work if they
have been damaged or abused. They will not function if they are or have
been wet. Store them in dry, airtight containers in dry places. But store them
where they are readily accessible.
Aerial VDSs, depending on their type and the conditions they are used in,
may not go very high. Again, use them only when there is a good chance
they will be seen.
A serious disadvantage of aerial flares is that they burn for only a short
time; most burn for less than 10 seconds. Most parachute flares burn for less
than 45 seconds. If you use a VDS in an emergency, do so carefully. Hold
hand-held flares over the side of the boat when in use. Never use a road
hazard flare on a boat; it can easily start a fire. Marine type flares are
specifically designed to lessen risk, but they still must be used carefully.
Aerial flares should be given the same respect as firearms since they are
firearms! Never point them at another person. Don't allow children to play
with them or around them. When you fire one, face away from the wind. Aim
it downwind and upward at an angle of about 60 degrees to the horizon. If
there is a strong wind, aim it somewhat more vertically. Never fire it straight
up. Before you discharge a flare pistol, check for overhead obstructions that
might be damaged by the flare. An obstruction might deflect the flare to
where it will cause injury or damage.
Fig. 11 Moisture-protected flares should be carried onboard any
Fig. 10 Internationally accepted distress signals vessel for use as a distress sianal
AL INFORMATION,
Disposal of VDS
Keep outdated flares when you get new ones. They do not meet legal
requirements, but you might need them sometime, and they may work. It is
illegal to fire a VDS on federal navigable waters unless an emergency exists.
Many states have similar laws.
Emergency Position Indicating Radio Beacon (EPIRB)
There is no requirement for recreational boats to have EPIRBs. Some
commercial and fishing vessels, though, must have them if they operate
beyond the three-mile limit. Vessels carrying six or fewer passengers for hire
must have EPIRBs under some circumstances when operating beyond the
three-mile limit. If you boat in a remote area or offshore, you should have an
EPIRB. An EPIRB is a small (about 6 to 20 in. high), battery-powered, radio
transmitting buoy-like device. It is a radio transmitter and requires a license
or an endorsement on your radio station license by the Federal
Communications Commission (FCC). EPIRBs are either automatically
activated by being immersed in water or manually by a switch.
Although not required by law, there are other pieces of equipment that are
good to have onboard.
All boats less than 16 feet long should carry a second means of
propulsion. A paddle or oar can come in handy at times. For most small
boats, a spare trolling or outboard motor is an excellent idea. If you carry a
spare motor, it should have its own fuel tank and starting power. If you use
an electric trolling motor, it should have its own battery.
All boats should carry at least one effective manual bailing device in
addition to any installed electric bilge pump. This can be a bucket, can,
scoop, hand-operated pump, etc. Ifyour battery "goes dead" it will not
operate your electric pump.
See Figure 12
All boats should carry a first aid kit. It should contain adhesive bandages,
gauze, adhesive tape, antiseptic, aspirin, etc. Check your first aid kit from
time to time. Replace anything that is outdated. It is to your advantage to
know how to use your first aid kit. Another good idea would be to take a Red
Cross first aid course.
See Figure 13
All boats should have anchors. Choose one of suitable size for your boat.
Better still, have two anchors of different sizes. Use the smaller one in calm
water or when anchoring for a short time to fish or eat. Use the larger one
when the water is rougher or for overnight anchoring.
One of the roles of the Coast Guard Auxiliary is to promote recreational
boating safety. This is why they conduct thousands of Courtesy Marine
Examinations each year. The auxiliarists who do these examinations are
well-trained and knowledgeable in the field.
These examinations are free and done only at the consent of ooat
owners. To pass the examination, a vessel must satisfy federal equipment
requirements and certain additional requirements of the coast guard
auxiliary. If your vessel does not pass the Courtesy Marine Examination, no
report of the failure is made. Instead, you will be told what you need to
correct the deficiencies. The examiner will return at your convenience to redo
the examination.
If your vessel qualifies, you will be awarded a safety decal. The decal
does not carry any special privileges, it simply attests to your interest in safe
boating.
Carry enough anchor line, of suitable size, for your boat and the waters in
which you will operate. If your engine fails you, the first thing you usually
should do is lower your anchor. This is good advice in shallow water where
you may be driven aground by the wind or water. It is also good advice in
windy weather or rough water, as the anchor, when properly affixed, will
usually hold your bow into the waves.
Your best means of summoning help in an emergency or in case of a
breakdown is a VHF-FM radio. You can use it to get advice or assistance
from the Coast Guard. In the event of a serious illness or injury aboard your
boat, the Coast Guard can have emergency medical equipment meet you
ashore.
Although the VHF radio is the best way to get help, in this day and
age, cell phones are a good backup source, especially for boaters on
inland waters. You probably already know where you get a signal when
boating, keep the phone charged, handy and off (so it doesn't bother
you when boating right?). Keep phone numbers for a local dockmaster,
coast guard, tow service or maritime police unit handy on board or
stored in your phone directory.
SELECTION
See Figure 14
The safety of the boat and her crew may depend on her compass. In
many areas, weather conditions can change so rapidly that, within minutes, a
skipper may find himself socked in by a fog bank, rain squall or just poor
visibility. Under these conditions, he may have no other means of keeping to
his desired course except with the compass. When crossing an open body of
water, his compass may be the only means of making an accurate landfall.
fry an adequately stocked
rd for the safety of the Fig. 13 Choose an anchor of sufficient Fig. 14 Don't hesitate to spend a few extra
weight to secure the boat without dragging dollars for a reliable compass
may be partially determined by the location of the wheel, shift lever and
throttle handle.
Fig. 15 The compass is a delicate instrument which should be
mounted securely in a position where it can be easily observed by
the helmsman
Durina thick weather when vou can neither see nor hear the exoected
aids to navigation, attempting to run out the time on a given course can
disrupt the pleasure of the cruise. The skipper gains little comfort in a chain
of soundings that does not match those given on the chart for the expected
area. Any stranding, even for a short time, can be an unnerving experience.
A pilot will not knowingly accept a cheap parachute. By the same token, a
good boater should not accept a bargain in lifejackets, fire extinguishers, or
compass. Take the time and spend the few extra dollars to purchase a
compass to fit your expected needs. Regardless of what the salesman may
tell you, postpone buying until you have had the chance to check more than
one make and model.
Lift each compass, tilt and turn it, simulating expected motions of the
boat. The compass card should have a smooth and stable reaction.
The card of a aood aualitv comoass will come to rest without oscillations
about the lubber's line. Reasonable movement in your hand, comparable to
the rolling and pitching of the boat, should not materially affect the reading.
INSTALLATION
4 See Figure 15
Proper installation of the compass does not happen by accident. Make a
critical check of the proposed location to be sure compass placement will
permit the helmsman to use it with comfort and accuracy. First, the compass
should be placed directly in front of the helmsman, and in such a position
that it can be viewed without body stress as he sits or stands in a posture of
relaxed alertness. The compass should be in the helmsman's zone of
comfort. If the compass is too far away, he may have to bend forward to
watch it; too close and he must rear backward for relief.
Second, give some thought to comfort in heavy weather and poor visibility
conditions during the day and night. In some cases, the compass position
Third, inspect the compass site to be sure the instrument will be at least
two feet from any engine indicators, bilge vapor detectors, magnetic
instruments, or any steel or iron objects. If the compass cannot be placed at
least two feet (six feet would be better but on a small craft, let's get real two
feet is usually pushing it) from one of these influences, then either the
compass or the other object must be moved, if first order accuracy is to be
expected.
Once the compass location appears to be satisfactory, give the compass
a test before installation. Hidden influences may be concealed under the
cabin top, forward of the cabin aft bulkhead, within the cockpit ceiling, or in a
wood-covered stanchion.
Move the compass around in the area of the proposed location. Keep an
eye on the card. A magnetic influence is the only thing that will make the
card turn. You can quickly find any such influence with the compass. if the
influence cannot be moved away or replaced by one of nonmagnetic
material, test to determine whether it is merely magnetic, a small piece of
iron or steel, or some magnetized steel. Bring the north pole of the compass
near the object, then shift and bring the south pole near it. Both the north
and south poles will be attracted if the compass is demagnetized. if the
object attracts one pole and repels the other, then the compass is
magnetized. If your compass needs to be demagnetized, take it to a shop
equipped to do the job PROPERLY.
After you have moved the compass around in the proposed mounting
area, hold it down or tape it in position. Test everything you feel might affect
the compass and cause a deviation from a true reading. Rotate the wheel
from hard over-to-hard over. Switch on and off all the lights, radios, radio
direction finder, radio telephone, depth finder and, if installed, the shipboard
intercom. Sound the electric whistle, turn on the windshield wipers, start the
engine (with water circulating through the engine), work !he throttle, and
move the gear shift lever. if the boat has an auxiliary generator, start it.
If the card moves during any one of these tests, the compass should be
relocated. Naturally, if something like the windshield wipers causes a slight
deviation, it may be necessary for you to make a different deviation table to
use only when certain pieces of equipment are operating. Bear in mind,
following a course that is off only a degree or two for several hours can
make considerable difference at the end, putting you on a reef, rock or shoal.
Check to be sure the intended compass site is solid. Vibration will
increase pivot wear.
Now, you are ready to mount the compass. To prevent an error on all
courses, the line through the lubber line and the compass card pivot must be
exactly parallel to the keel of the boat. You can establish the fore-and-aft line
of the boat with a stout cord or string. Use care to transfer this line to the
compass site. If necessary, shim the base of the compass until the stile-type
lubber line (the one affixed to the case and not aimbaledl is vertical when the
boat is on an even keel. Drill the holes and mount the compass.
COMPASS PRECAUTIONS
See Figures 16,17 and 18
Many times an owner will install an expensive stereo system in the cabin
of his boat. It is not uncommon for the speakers to be mounted on the aft
bulkhead up against the overhead (ceiling). In almost every case, this
position places one of the speakers in very close proximity to the compass,
mounted above the ceiling.
. .well think again, as seemingly
Fig. 16 This compass is giving an accurate objects may cause serious Fig. 18 . ..a compass reading off by just a
reading, right? few degrees could lead to disaster
You probably already know that a magnet is used in the operation of the
speaker. Therefore, it is very likely that the speaker, mounted almost under
the compass in the cabin will have a very pronounced effect on the compass
accuracy.
Consider the following test and the accompanying photographs as proof:
First, the compass was read as 190 degrees while the boat was secure in
her slip,
Next. a full can of soda in an aluminum can was placed on we side and
the compass read as 204 degrees, a good 14 degrees oft.
Next. the full can was moved to the opposite side of the compass and
again a reading was observed, this time as 189 degrees, 11 degrees off from
the original reading.
Finally, the contents of the can were consumed, the can placed on both
sides of the compass with NO effect on the compass reading.
Two very important conclusions can be drawn from these tests.
Something must have been in the contents of the can to affect the
compass so drastically.
Keep even innocent things clear of the compass to avoid any possible
error in the boat's heading.
B Remember, a boat moving through the water at 10 knots on a
compass error of just 5 degrees will be almost 1.5 miles oft course in
only ONE hour. At night, or in thick weather, this could very possibly
put the boat on a reef, rock or shoal with disastrous results.
It is virtually impossible to anticipate all of the hazards involved with
maintenance and service, but care and common sense will prevent most
accidents.
The rules of safety for mechanics range from "don't smoke around
gasoline," to "use the proper tool(s) for the job." The trick to avoiding injuries
is to develop safe work habits and to take every possible precaution.
Whenever you are working on your boat, pay attention to what you are
doing. The more you pay attention to details and what is going on around
you, the less likely you will be to hurt yourself or damage your boat.
Do keep a fire extinguisher and first aid kit handy.
Do wear safety glasses or goggles when cutting, drilling, grinding or
prying, even if you have 20-20 vision. If you wear glasses for the sake of
vision, wear safety goggles over your regular glasses.
Do shield your eyes whenever you work around the battery. Batteries
contain sulfuric acid. In case of contact with the eyes or skin, flush the area
with water or a mixture of water and baking soda; then seek immediate
medical attention.
0
Do use adequate ventilation when working with any chemicals or
hazardous materials.
5
Do disconnect the negative battery cable when working on the
electrical system. The secondary ignition system contains EXTREMELY
HIGH VOLTAGE. In some cases it can even exceed 50,000 volts.
Furthermore, an accidental attempt to start the engine could cause the
propeller or other components to rotate suddenly causing a potentially
dangerous situation,
5
Do follow manufacturer's directions whenever working with potentially
hazardous materials. Most chemicals and fluids are poisonous if taken
internally.
See Figures 19 and 20
Carry a few tools and some spare parts, and learn how to make minor
repairs. Many search and rescue cases are caused by minor breakdowns
that boat operators could have repaired. Carry spare parts such as
propellers, fuses or basic ignition components (like spark plugs, wires or
even ignition coils) and the tools necessary to install them.
Fig. 20 A few wrenches, a screwdriver and maybe a pair of pliers
can be very helpful to make emergency repairs
Do properly maintain your tools. Loose hammerheads, mushroomed
punches and chisels, frayed or poorly grounded electrical cords, excessively
worn screwdrivers, spread wrenches (open end), cracked sockets, or
slipping ratchets can cause accidents.
* Likewise, keep your tools clean; a greasy wrench can slip off a bolt
head, ruining the bolt and often harming your knuckles in the process.
Do use the proper size and type of tool for the job at hand. Do select a
wrench or socket that fits the nut or bolt. The wrench or socket should sit
straight, not cocked.
Do, when possible, pull on a wrench handle rather than push on it, and
adjust your stance to prevent a fall.
Do be sure that adjustable wrenches are tightly closed on the nut or
bolt and pulled so that the force is on the side of the fixed jaw. Better yet,
avoid the use of an adjustable if you have a fixed wrench that will fit.
0
Do strike squarely with a hammer; avoid glancing blows.
Do use common sense whenever you work on your boat or motor. If a
situation arises that doesn't seem right, sit back and have a second look. It
may save an embarrassing moment or potential damage to your beloved
boat.
* Don't run the engine in an enclosed area or anywhere else without
proper ventilation -EVER! Carbon monoxide is poisonous; it takes a long
time to leave the human body and you can build up a deadly supply of it in
your system by simply breathing in a little every day. You may not realize you
are slowly poisoning yourself.
Don't work around moving parts while wearing loose clothing. Short
sleeves are much safer than long, loose sleeves. Hard-toed shoes with
neoprene soles protect your toes and give a better grip on slippery surfaces.
Jewelry, watches, large belt buckles, or body adornment of any kind is not
safe working around any craft or vehicle. Long hair should be tied back
under a hat.
* Don't use pockets for toolboxes. A fall or bump can drive a screwdriver
deep into your body. Even a rag hanging from your back pocket can wrap
around a spinning shaft.
* Don't smoke when working around gasoline, cleaning solvent or other
flammable material.
@
Don't smoke when working around the battery. When the battery is
being charged, it gives off explosive hydrogen gas. Actually, you shouldn't
Troubleshooting can be defined as a methodical process during which
one discovers what is causing a problem with engine operation. Although it is
often a feared process to the uninitiated, there is no reason to believe that
you cannot figure out what is wrong with a motor, as long as you follow a few
basic rules.
To begin with, troubleshooting must be systematic. Haphazardly testing
one component, then another, might uncover the problem, but it will more
likely waste a lot of time. True troubleshooting starts by defining the problem
and performing systematic tests to eliminate the largest and most likely
causes first.
Start all troubleshooting by eliminating the most basic possible causes.
Begin with a visual inspection of the boat and motor. If the engine won't
crank, make sure that the kill switch or safety lanyard is in the proper
position. Make sure there is fuel in the tank and the fuel system is primed
before condemning the carburetor or fuel injection system. On electric start
motors, make sure there are no blown fuses, the battery is fully charged, and
the cable connections (at both ends) are clean and tight before suspecting a
bad starter, solenoid or switch.
The majority of problems that occur suddenly can be fixed by simply
identifying the one small item that brought them on. A loose wire, a clogged
passage or a broken component can cause a lot of trouble and are often the
cause of a sudden performance problem.
The next most basic step in troubleshooting is to test systems before
components. For example, if the engine doesn't crank on an electric start
motor, determine if the battery is in good condition (fully charged and
properly connected) before testing the starting system. If the engine cranks,
but doesn't start, you know already know the starting system and battery (if it
cranks fast enough) are in good condition, now it is time to look at the
ignition or fuel systems. Once you've isolated the problem to a particular
system, follow the troubleshooting/testing procedures in the section for that
system to test either subsystems (if applicable, for example: the starter
circuit) or components (starter solenoid).
Deflector Piston1 Exhaust
\ A
smoke anyway, it's bad for you. Instead, save the cigarette money and put it
into your boat!
Don't use gasoline to wash your hands; there are excellent soaps
available. Gasoline contains dangerous additives that can enter the body
through a cut or through your pores. Gasoline also removes all the natural
oils from the skin so that bone dry hands will suck up oil and grease.
* Don't use screwdrivers for anything other than driving screws! A
screwdriver used as a prying tool can snap when you least expect it, causing
injuries. At the very least, you'll ruin a good screwdriver.
See Figures 21 and 22
Before attempting to troubleshoot a problem with your motor, it is
important that you understand how it operates. Once normal engine or
system operation is understood, it will be easier to determine what might be
causing the trouble or irregular operation in the first place. System
descriptions are found throughout this service, but the basic mechanical
operating principles for both 2-stroke engines (like most of the outboards
covered here) and 4-stroke engines (like some outboards and like your car)
are given here. A basic understanding of both types of engines is useful not
only in understanding and troubleshooting your outboard, but also for dealing
with other motors in your life.
All motors covered by this service (and probably MOST of the motors you
own) operate according to the Otto cycle principle of engine operation. This
means that all motors follow the stages of intake, compression, power and
exhaust. But, the difference between a 2- and 4-stroke motor is in how many
times the piston moves up and down within the cylinder to accomplish this.
On 2-stroke motors (as the name suggests) the four cycles take place in 2
movements (one up and one down) of the piston. Again, as the name
suggests, the cycles take place in 4 movements of the piston for 4-stroke
motors.
2-STROKE MOTORS
The 2-stroke engine differs in several ways from a conventional four-
stroke (automobile or marine) engine.
1. The intakelexhaust method by which the fuel-air mixture is delivered
to the combustion chamber.
2. The complete lubrication system.
3. The frequency of the power stroke.
Let's discuss these differences briefly (and compare 2-stroke engine
operation with 4-stroke engine operation.)
I0v^/) Connecting
Intake rod
port
Intake Compression Ignition power stroke Exhaust
Fig. 21 The complete piston cycle of a 2-stroke motor (intake, compression, power and exhaust)
Compression 1 4.Exhaust
I
1 Fig. 22 The complete piston cycle of a 4-stroke motor (intake, compression, power and exhaust)
@ See Figures 23 thru 26
Two-stroke engines utilize an arrangement of port openings to admit fuel
to the combustion chamber and to purge the exhaust gases after burning
has been completed. The ports are located in a precise pattern in order for
them to be open and closed off at an exact moment by the piston as it
moves up and down in the cylinder. The exhaust port is located slightly
higher than the fuel intake port. This arrangement opens the exhaust port
first as the piston starts downward and therefore, the exhaust phase begins
a fraction of a second before the intake phase.
Actually, the intake and exhaust ports are spaced so closely together that
both open almost simultaneously. For this reason, some 2-stroke engines
utilize deflector-type pistons. This design of the piston top serves two
purposes very effectively.
First, it creates turbulence when the incoming charge of fuel enters the
combustion chamber. This turbulence results in a more complete burning of
the fuel than if the piston top were flat. The second effect of the deflector-
type piston crown is to force the exhaust gases from the cylinder more
rapidly.
Loop charged motors, or as they are commonly called "loopers", differ in
how the airlfuel charge is introduced to the combustion chamber. Instead of
the charge flowing across the top of the piston from one side of the cylinder
to the other (CV) the use a looping action on top of the piston as the charge
is forced through irregular shaped openings cut in the piston's skirt. In an LV
motor, the charge is forced out from the crankcase by the downward motion
of the piston, through the irregular shaped openings and transferred upward
by long, deep grooves in the cylinder wall. The charge completes its looping
action by entering the combustion chamber, just above the piston, where the
upward motion of the piston traps it in the chamber and compresses it for
optimum ignition power.
Unlike the knife-edged deflector top pistons used in CV motors, the piston
domes on Loop motors are relatively flat.
Over the years various outboard manufacturers used both LV and
CV configurations in many popular lines of 2-stroke motors.
These systems of intake and exhaust are in marked contrast to individual
intake and exhaust valve arrangement employed on four-stroke engines (and
the mechanical methods of opening and closing these valves).
It should be noted here that there are some 2-stroke engines that
utilize a mechanical valve train, though it is very different from the
valve train employed by most 4-stroke motors. Rotary 2-stroke engines
use a circular valve or rotating disc that contains a port opening
around part of one edge of the disc. As the engine (and disc) turns, the
opening aligns with the intake port at and for a predetermined amount
of time, closing off the port again as the opening passes by and the
solid portion of the disc covers the port.
Lubrication
A 2-stroke engine is lubricated by mixing oil with the fuel. Therefore,
various parts are lubricated as the fuel mixture passes through the
Deflector Exhaust
I port n Exhaust
"Intake
port
Intake Exhaust
ig. 23 The intake and exhaust cycles of a two-stroke engine -
toss flow (CV) design shown
crankcase and the cylinder. In contrast, four-stroke engines have a
crankcase containing oil. This oil is pumped through a circulating system and
returned to the crankcase to begin the routing again.
Power Stroke
The combustion cycle of a 2-stroke engine has four distinct phases.
1. Intake
2. Compression
3. Power
4. Exhaust
The four phases of the cycle are accomplished with each up and down
stroke of the piston, and the power stroke occurs with each complete
revolution of the crankshaft. Compare this system with a four-stroke engine.
A separate stroke of the piston is required to accomplish each phase of the
cycle and the power stroke occurs only every other revolution of the
crankshaft. Stated another way, two revolutions of the four-stroke engine
crankshaft are required to complete one full cycle, the four phases.
Fig. 25 Cutaway view of a typical loop- Fig. 26 The combustion chamber of a
Fig. 24 Cross-sectional view of a typical
loop-charged cylinder, showing charge flow
while piston is moving downward
charged cylinder, depicting exhaust leaving
the cylinder as the charge enters through 3
ports in the piston
typical looper, notice the piston is far
enough down the cylinder bore to reveal
intake and exhaust ports
Physical Laws
+ See Figure 27
The 2-stroke engine is able to function because of two very simple
physical laws.
One: Gases will flow from an area of high pressure to an area of lower
pressure. A tire blowout is an example of this principle. The high-pressure air
escapes rapidly if the tube is punctured.
Two: if a gas is compressed into a smaller area, the pressure increases,
and if a gas expands into a larger area, the pressure is decreased.
If these two laws are kept in mind, the operation of the 2-stroke engine
will be easier understood.
Actual Operation
+ See Figure 21
The engine described here is of a carbureted type. EFI or DFI
(DIIFICHT or E -Tec) motors operate similarly for intake of the air
charge and for exhaust of the unburned gasses. Obviously though, the
very nature of fuel injection changes the actual delivery of the fueiloil
charge.
Beginning with the piston approaching top dead center on the
compression stroke: the intake and exhaust ports are ~hvsicallv closed
(blocked) by the piston. During this stroke, the reed valve is open (because
as the piston moves upward, the crankcase volume increases, which
reduces the crankcase pressure to less than the outside atmosphere
(creates a vacuum under the piston). The spark plug fires; the compressed
fuel-air mixture is ignited; and the power stroke begins.
As the piston moves downward on the power stroke, the combustion
chamber is filled with burnina aases. As the exhaust port is uncovered, the
gases, which are under great pressure, escape rapidly through the exhaust
ports. The piston continues its downward movement. Pressure within the
crankcase (again, under the piston) increases, closing the reed valves
against their seats. The crankcase then becomes a sealed chamber so the
air-fuel mixture becomes compressed (pressurized) and ready for delivery to
the combustion chamber. As the piston continues to move downward, the
intake port is uncovered. The fresh fuel mixture rushes through the intake
port into the combustion chamber striking the top of the piston where it is
deflected along the cylinder wail. The reed valve remains closed until the
piston moves upward again.
When the piston begins to move upward on the compression stroke, the
reed valve opens because the crankcase volume has been increased,
reducing crankcase pressure to less than the outside atmosphere. The
intake and exhaust ports are closed and the fresh fuel charge is compressed
inside the combustion chamber.
Pressure in the crankcase (beneath the piston) decreases as the piston
moves upward and a fresh charge of air flows through the carburetor picking
up fuel. As the piston approaches top dead center, the spark plug ignites the
air-fuel mixture, the power stroke begins and one complete Otto cycle has
been completed.
Induced
low air
pressure
\
\
Atmospheric air pressure
Fig. 27 Air flow principal for a modern carburetor
4-STROKE MOTORS
See Figure 22
The 4-stroke motor may be easier to understand for some people either
because of its prevalence in automobile and street motorcycle motors today
or perhaps because each of the four strokes corresponds to one distinct
phase of the Otto cycle. Essentially, a 4-stroke engine completes one Otto
cycle of intake, compression, ignitionlpower and exhaust using two full
revolutions of the crankshaft and four distinct movements of the piston
(down, up, down and up).
Intake
The intake stroke begins with the piston near the top of its travel. As
crankshaft rotation begins to pull thepiston downward,' the exhaust valve
closes and the intake opens. As volume of the combustion chamber
increases, a vacuum iscreated that draws in the airlfuel mixture from the
intake manifold.
Compression
Once the piston reaches the bottom of its travel, crankshaft rotation will
begin to force it upward. At this point the intake valve closes. As the piston
rises in the bore, the volume of the sealed combustion chamber (both intake
and exhaust valves are closed) decreases and the airlfuel mixture is
compressed. This raises the temperature and pressure of the mixture and
increases the amount of force generated by the expanding gases during the
IgnitionIPower stroke.
As the piston approaches top dead center (the highest point of travel in
the bore), the spark plug will fire, igniting the airlfuel mixture. The resulting
combustion of the airlfuel mixture forces the piston downward, rotating the
crankshaft (causing other pistons to move in other phaseslstrokes of the Otto
cycle on multi-cylinder motors).
xhaust
As the piston approaches the bottom of the IgnitionIPower stroke, the
exhaust valve opens. When the piston begins its upward path of travel once
again, any remaining unburned gasses are forced out through the exhaust
valve. This completes one Otto cycle, which begins again as the piston
passes top dead center, the intake valve opens and the Intake stroke starts.
COMBUSTION
Whether we are talking about a 2-or 4-stroke engine, all Otto cycle,
internal combustion engines require three basic conditions to operate
properly,
1. Compression
2. Ignition (Spark)
3. Fuel
A lack of any one of these conditions will prevent the engine from
operating. A problem with any one of these will manifest itself in hard-starting
or poor performance.
Compression
An engine that has insufficient compression will not draw an adequate
supply of airlfuel mixture into the combustion chamber and, subsequently,
will not make sufficient power on the power stroke. A lack of compression in
just one cylinder of a multi-cylinder motor will cause the motor to stumble or
run irregularly.
But, keep in mind that a sudden change in compression is unlikely in 2-
stroke motors (unless something major breaks inside the crankcase, but that
would usually be accompanied by other symptoms such as a loud noise
when it occurred or noises during operation). On 4-stroke motors, a sudden
change in compression is also unlikely, but could occur if the timing belt or
chain was to suddenly break. Remember that the timing belUchain is used to
synchronize the valve train with the crankshaft. If the valve train suddenly
ceases to turn, some intake and some exhaust valves will remain open,
relieving compression in that cylinder.
Ignition (Spark)
Traditionally, the ignition system is the weakest link in the chain of
conditions necessary for engine operation. Spark plugs may become worn or
WORK GLOVES
See Figure 28
Unless you think scars on your hands are cool, enjoy pain and like
wearing bandages, get a good pair of work gloves. Canvas or leather gloves
are the best. And yes, we realize that there are some jobs involving small
parts that can't be done while wearing work gloves. These jobs are not the
ones usually associated with hand injuries.
A good pair of rubber gloves (such as those usually associated with dish
washing) or vinyl gloves is also a great idea. There are some liquids such as
solvents and penetrants that don't belong on your skin. Avoid burns and
rashes. Wear these gloves.
fouled, wires will deteriorate allowing arcing or misfiring, and poor
connections can place an undue load on coils leading to weak spark or even
a failed coil. The most common question asked by a technician under a no-
start condition is: "do Ihave spark and fuel" (as they've already determined
that they have compression).
A quick visual inspection of the spark plug(s) will answer the question as
to whether or not the plug(s) islare worn or fouled. While the engine is shut
OFF a physical check of the connections could show a loose primary or
secondary ignition circuit wire. An obviously physically damaged wire may
also be an indication of system problems and certainly encourages one to
inspect the related system more closely.
If nothing is turned up by the visual inspection, perform the Spark Test
provided in the Ignition System section to determine if the problem is a lack
of or a weak spark. If the problem is not compression or spark, it's time to
look at the fuel system.
Fuel
If compression and spark is present (and within spec), but the engine
won't start or won't run properly, the only remaining condition to fulfill is fuel.
As usual, start with the basics. Is the fuel tank full? Is the fuel stale? If the
engine has not been run in some time (a matter of months, not weeks) there
is a good chance that the fuel is stale and should be properly disposed of
and replaced,
Depending on how stale or contaminated (with moisture) the fuel is,
it may be burned in an automobile or in yard equipment, though it
would be wise to mix it well with a much larger supply of fresh gasoline
to prevent moving your driveability problems to that motor.
better to get the lawn tractor stuck on stale gasoline than it would be to
have your boat motor quit in the middle of the bay or lake.
For hard starting motors, is the choke or primer system operating
properly. Remember that the chokelprime should only be used for cold
starts. A true cold start is really only the first start of the day, but it may be
applicable to subsequent starts on cooler days, if the engine sat for more
than a few hours and completely cooled off since the last use. Applying the
primer to the motor for a hot start may flood the engine, preventing it from
starting properly. One method to clear a flood is to crank the motor while the
engine is at wide-open throttle (allowing the maximum amount of air into the
motor to compensate for the excess fuel). But, keep in mind that the throttle
should be returned to idle immediately upon engine start-up to prevent
damage from over-rewing.
Fuel delivery and pressure should be checked before delving into the
carburetor(s) or fuel injection system. Make sure there are no clogs in the
fuel line or vacuum leaks that would starve the motor of fuel.
Make sure that all other possible problems have been eliminated before
touching the carburetor. It is rare that a carburetor will suddenly require an
adjustment in order for the motor to run properly. It is much more likely that
an improperly stored motor (one stored with untreated fuel in the carburetor)
would suffer from one or more clogged carburetor passages sometime after
shortly returning to service. Fuel will evaporate over time, leaving behind
gummy deposits. If untreated fuel is left in the carburetor for some time
(again typically months more than weeks), the varnish left behind by
evaporating fuel will likely clog the small passages of the carburetor and
cause problems with engine performance. If you suspect this, remove and
disassemble the carburetor following procedures under Fuel System.
And lastly, an option. If you're tired of being greasy and dirty all the time,
ao to the drua store and buv a box of disoosable latex aloves like medical
professionals"wear. You can handle greasy parts, small tasks, wash
parts, etc. all without getting dirty! These gloves take a surprising amount of
abuse without tearing and aren't expensive. Note however, that some people
are allergic to the latex or the powder used inside some gloves, so pay
attention to what you buy.
EYE AND EAR PROTECTION
 See Figures 29 and 30
Don't begin any job without a good pair of work goggles or impact
resistant glasses! When doing any kind of work, it's all too easy to avoid eye
injury through this simple precaution. And don't just buy eye protection and
leave it on the shelf. Wear it all the timel Things have a habit of breaking,
Fig. 29 Don't begin major repairs without a
Fig, 30 Things have a habit of, splashing,
spraying, splintering and flying around
during repairs
chipping, splashing, spraying, splintering and flying around. And, for some
reason, your eye is always in the way!
If you wear vision-correcting glasses as a matter of routine, get a pair
made with polycarbonate lenses. These lenses are impact resistant and are
available at any optometrist.
Often overlooked is hearing protection. Engines and power tools are
noisy! Loud noises damage your ears. It's as simple as that! The simplest
and cheapest form of ear protection is a pair of noise-reducing ear plugs.
Cheap insurance for your ears! And, they may even come with their own,
cute little carrying case.
More substantial, more protection and more money is a good pair of noise
reducing earmuffs. They protect from all but the loudest sounds. Hopefully
those are sounds that you'll never encounter since they're usually associated
with disasters.
WORK CLOTHES
Everyone has "work clothes." Usually these consist of old jeans and a
shirt that has seen better days. That's fine. In addition, a denim work apron
is a nice accessory. It's rugged, can hold some spare bolts, and you don't
feel bad wiping your hands or tools on it. That's what it's for.
When working in cold weather, a one-piece, thermal work outfit is
invaluable. Most are rated to below freezing temperatures and are ruggedly
constructed. Just look at what local marine mechanics are wearing and that
should give you a clue as to what type of clothing is good.
There is a whole range of chemicals that you'll find handy for
maintenance and repair work. The most common types are: lubricants,
penetrants and sealers. Keep these handy. There are also many chemicals
that are used for detailing or cleaning.
When a particular chemical is not being used, keep it capped, upright and
in a safe place. These substances may be flammable, may be irritants or
might even be caustic and should always be stored properly, used properly
and handled with care. Always read and follow all label directions and be
sure to wear hand and eye protection!
LUBRICANTS & PENETRANTS
See Figure 31
Anti-seize is used to coat certain fasteners prior to installation. This can
be especially helpful when two dissimilar metals are in contact (to help
prevent corrosion that might lock the fastener in place). This is a good
practice on a lot of different fasteners, BUT, NOT on any fastener that might
vibrate loose causing a problem. If anti-seize is used on a fastener, it should
be checked periodically for proper tightness.
Lithium grease, chassis lube, silicone grease or a synthetic brake caliper
grease can all be used pretty much interchangeably. All can be used for
coating rust-prone fasteners and for facilitating the assembly of parts that are
a tight fit. Silicone and synthetic greases are the most versatile.
 Silicone dielectric grease is a non-conductor that is often used to
coat the terminals of wiring connectors before fastening them. It may
sound odd to coat metal portions of a terminal with something that
won't conduct electricity, but here is it how it works. When the
connector is fastened the metal-to-metal contact between the terminals
will displace the grease (allowing the circuit to be completed). The
grease that is displaced will then coat the non-contacted surface and
the cavity around the terminals, SEALING them from atmospheric
moisture that could cause corrosion.
Silicone spray is a good lubricant for hard-to-reach places and parts that
shouldn't be gooped up with grease.
Penetrating oil may turn out to be one of your best friends when taking
something apart that has corroded fasteners. Not only can they make a job
easier, they can really help to avoid broken and stripped fasteners. The most
familiar penetrating oils are Liquid [email protected] and [email protected] A newer
penetrant, PB [email protected] works very well (and has become a mainstay in our
shops). These products have hundreds of uses. For your purposes, they are
vital!
Before disassembling any part, check the fasteners. If any appear rusted,
soak them thoroughly with the penetrant and let them stand while you do
something else (for particularly rusted or frozen parts you may need to soak
them a few days in advance). This simple act can save you hours of tedious
work trying to extract a broken bolt or stud.
SEALANTS
9 See Figures 32 and 33
Sealants are an indispensable part for certain tasks, especially if you are
trying to avoid leaks. The purpose of sealants is to establish a leak-proof
bond between or around assembled parts. Most sealers are used in
conjunction with gaskets, but some are used instead of conventional gasket
material.
The most common sealers are the non-hardening types such as
[email protected] No.2 or its equivalents. These sealers are applied to the mating
surfaces of each part to be joined, then a gasket is put in place and the parts
are assembled.
 A sometimes overlooked use for sealants like RTV is on the threads
of vibration prone fasteners.
One very helpful type of non-hardening sealer is the "high tack" type. This
type is a very sticky material that holds the gasket in place while the parts
are being assembled. This stuff is really a good idea when you don't have
enough hands or fingers to keep everything where it should be.
The stand-alone sealers are the Room Temperature Vulcanizing (RTV)
silicone gasket makers. On some engines, this material is used instead of a
gasket. In those instances, a gasket may not be available or, because of the
shape of the mating surfaces, a gasket shouldn't be used. This stuff, when
used in conjunction with a conventional gasket, produces the surest bonds.
RTV does have its limitations though. When using this material, you will
have a time limit. It starts to set-up within 15 minutes or so, so you have to
assemble the parts without delay. In addition, when squeezing the material
out of the tube, don't drop any glops into the engine. The stuff will form and
set and travel around a cooling passage, possibly blocking it. Also, most
types are not fuel-proof. Check the tube for all cautions.
Fig. 31 Keep a supply of anti-seize,
penetrating oil, lithium grease, electronic Fig. 32 Sealants are essential for preventing
leaks
CLEANERS
+ See Figures 34 and 35
There are two basic types of cleaners on the market today: parts cleaners
and hand cleaners. The parts cleaners are for the parts; the hand cleaners
are for you. They are not interchangeable,
There are many good, non-flammable, biodegradable parts cleaners on
the market. These cleaning agents are safe for you, the parts and the
environment. Therefore, there is no reason to use flammable, caustic or toxic
substances to clean your parts or tools.
Fig. 34 Citrus hand cleaners not only work well, but they smell
pretty good too. Choose one with pumice for added cleaning power
+ See Figure 36
Tools; this subject could fill a completely separate service. The first thing
you will need to ask yourself, is just how involved do you plan to get. If you
are serious about maintenance and repair you will want to gather a quality
set of tools to make the job easier, and more enjoyable. BESIDES, TOOLS
ARE FUN!!!
Almost every do-it-yourselfer loves to accumulate tools. Though most find
a way to perform jobs with only a few common tools, they tend to buy more
over time, as money allows. So gathering the tools necessary for
maintenance or repair does not have to be an expensive, overnight
proposition.
When buying tools, the saying "You get what you pay for . . ." is absolutely
true! Don't go cheap! Any hand tool that you buy should be drop forged
and/or chrome vanadium. These two qualities tell you that the tool is strong
enough for :r,s job. With any tool, go with a name that you've heard of
As far as hand cleaners go; the waterless types are the best. They have
always been efficient at cleaning, but they used to all leave a pretty smelly
odor. Recently though, most of them have eliminated the odor and added
stuff that actually smells good. Make sure that you pick one that contains
lanolin or some other moisture-replenishing additive. Cleaners not only
remove grease and oil but also skin oil.
M Most women already know to use a hand lotion when you're all
cleaned up. It's okay. Real men DO use hand lotion too! Believe it or
not, using hand lotion before your hands are dirty will actually make
them easier to clean when you're finished with a dirty job. Lotion seals
your hands, and keeps dirt and grease from sticking to your skin.
Fig. 35 The use of hand lotion seals your hands and keeps dirt and
grease from sticking to your skin
before, or, that is recommended buy your local professional retailer. Let's go
over a list of tools that you'll need.
Most of the world uses the metric system. However, some American-built
engines and aftermarket accessories use standard fasteners. So,
accumulate your tools accordingly. Any good DIYer should have a decent set
of both U.S. and metric measure tools.
M Don't be confused by terminology. Most advertising refers to "SAE
and metric", or "standard and metric." Both are misnomers. The
Society of Automotive Engineers (SAE) did not invent the English
system of measurement; the English did. The SAE likes metrics just
fine. Both English (US.) and metric measurements are SAE approved.
Also, the current "standard" measurement IS metric. So, if it's not
metric, it's US. measurement.
ATION SAF TY & TOOL
SOCKET SETS
+ See Figures 37 thru 43
Socket sets are the most basic hand tools necessary for repair and
maintenance work. For our purposes, socket sets come in three drive sizes:
114 inch, 318 inch and 112 inch. Drive size refers to the size of the drive lug
on the ratchet, breaker bar or speed handle.
A 318 inch set is probably the most versatile set in any mechanic's
toolbox. It allows you to get into tight places that the larger drive ratchets
can't and gives you a range of larger sockets that are still strong enough for
heavy-duty work. The socket set that you'll need should range in sizes from
114 in. through 1 in. for standard fasteners, and a 6mm through 19mmfor
metric fasteners.
Fig. 36 Socket holders, especially the magnetic type, are handy
items to keep tools in order
You'll need a good 112 in. set since this size drive lug assures that you
won't break a ratchet or socket on large or heavy fasteners. Also, torque
wrenches with a torque scale high enough for larger fasteners are usually
112 in. drive.
Plus, 114 in. drive sets can be very handy in tight places. Though they
usually duplicate functions of the 318 in. set, 114 in. drive sets are easier to
use for smaller bolts and nuts.
As for the sockets themselves, they come in shallow (standard) and deep
lengths as well as 6 or 12 point. The 6 and 12 points designation refers to
how many sides are in the socket itself. Each has advantages. The 6 point
socket is stronaer and less Drone to slipping which would strip a bolt head or
nut. 12 point sockets are more commo'n; usually less expensive and can
operate better in tight places where the ratchet handle can't swing far.
Standard length sockets are good for just about all jobs, however, some
stud-head bolts, hard-to-reach bolts, nuts on long studs, etc., require the
deep sockets.
I
Fig. 37 A 318 in. socket set is probably the most versatile tool in
any mechanic's tool box
Fig. 38 A swivel (U-joint) adapter (left), a Fig. 40 Shallow sockets (top) are good for
wobble-head adapter (center) and a 112 in.- Fig. 39 Ratchets come in all sizes and most lobs. But, some bolts require deep
to-318 in. adapter (right) configurations from rigid to swivel-headed sockets (bottom)
Fig. 41 Hex-head fasteners require a socket Fig. 43 . . . and tamper resistant drivers are
with a hex shaped driver Fig. 42 [email protected] drivers . . . required to remove special fasteners
L INFORMATI
Most marine manufacturers use recessed hex-head fasteners to retain
many of the engine parts. These fasteners require a socket with a hex
shaped driver or a large sturdy hex key. To help prevent torn knuckles, we
would recommend that you stick to the sockets on any tight fastener and
leave the hex keys for lighter applications. Hex driver sockets are available
individuallv or in sets iust like conventional sockets.
More and more, manufacturers are using [email protected] head fasteners, which
were once known as tamoer resistant fasteners (because manv weowle did
not have tools with the necessary odd driver shape). Since TO&J fasteners
have become commonplace in many DIYer tool boxes, manufacturers
designed newer tamper resistant fasteners that are essentially [email protected] head
bolts that contain a small protrusion in the center (requiring the driver to
contain a small hole to slide over the protrusion. Tamper resistant fasteners
are often used where the manufacturer would prefer only knowledgeable
mechanics or advanced Do-It-Yourselfers (DIYers) work.
Torque Wrenches
See Figure 44
In most applications, a torque wrench can be used to ensure proper
installation of a fastener. Toraue wrenches come in various desians and most
stores will carry a variety to suit your needs. A torque wrench should be used
any time you have a specific torque value for a fastener. Keep in mind that
because there is no worldwide standardization of fasteners, so charts or
figure found in each repair section refer to the manufacturer's fasteners. Any
general guideline charts that you might come across based on fastener size
(they are sometimes included in a repair manual or with torque wrench
packaging) should be used with caution. Just keep in mind that if you are
using the right tool for the job, you should not have to strain to tighten a
fastener.
Head
SWare
Fig. 44 Three types of torque wrenches. Top
to bottom: a 318 in. drive beam type that
reads in inch Ibs., a 112 in. drive clicker type
Beam Type
+ See Figures 45 and 46
The beam type torque wrench is one of the most popular styles in use. If
used properly, it can be the most accurate also. It consists of a pointer
attached to the head that runs the length of the flexible beam (shaft) to a
scale located near the handle. As the wrench is pulled, the beam bends and
the pointer indicates the torque using the scale.
Click (Breakaway) Type
+ See Figures 47 and 48
Another popular torque wrench design is the click type. The clicking
mechanism makes achieving the proper torque easy and most use a
ratcheting head for ease of bolt installation. To use the click type wrench you
pre-adjust it to a torque setting. Once the torque is reached, the wrench has
a reflex signaling feature that causes a momentary breakaway of the torque
wrench body, sending an impulse to the operator's hand. But be careful, as
continuing the turn the wrench after the momentary release will increase
torque on the fastener beyond the specified setting.
BREAKER BARS
See Figure 49
Breaker bars are long handles with a drive lug. Their main purpose is to
provide extra turning force when breaking loose tight bolts or nuts. They
come in all drive sizes and lengths. Always take extra precautions and use
the proper technique when using a breaker bar (pull on the bar, don't push,
to prevent skinned knuckles).
Scale Pivoted
Beam or
Measuring
Element
Fig. 46 A beam type torque wrench consists
of a pointer attached to the head that runs
the length of the flexible beam (shaft) to a
scale located near the handle
Fig. 48 Setting the torque on a click type
Fig. 47 A click type or breakaway torque wrench involves turning the handle until the Fig. 49 Breaker bars are great for loosening
wrench -note this one has a pivoting head specification appears on the dial larae or stuck fasteners
WRENCHES
See Figures 50 thru 54
Basically, there are 3 kinds of fixed wrenches: open end, box end, and
combination.
Open-end wrenches have 2-jawed openings at each end of the wrench.
These wrenches are able to fit onto just about any nut or bolt. They are
extremely versatile but have one major drawback. They can slip on a worn or
rounded bolt head or nut, causing bleeding knuckles and a useless fastener.
H Line wrenches are a special type of open-end wrench designed to fit
onto more of the fastener than standard open-end wrenches, thus
reducing the chance of rounding the corners of the fastener.
Box-end wrenches have a 360' circular jaw at each end of the wrench.
They come in both 6 and 12 point versions just like sockets and each type
has some of the same advantages and disadvantages as sockets.
Combination wrenches have the best of both. They have a 2-jawed open
end and a box end. These wrenches are probably the most versatile.
As for sizes, you'll probably need a range similar to that of the sockets,
about 114 in. through 1 in. for standard fasteners, or 6mm through 19mm for
metric fasteners. As for numbers, you'll need 2 of each size, since, in many
instances, one wrench holds the nut while the other turns the bolt. On most
fasteners, the nut and bolt are the same size so having two wrenches of the
same size comes in handy.
@ Although you will typically just need the sizes we specified, there
are some exceptions. Occasionally you will find a nut that is larger. For
these, you will need to buy ONE expensive wrench or a very large
adjustable. Or you can always just convince the spouse that we are
talking about safety here and buy a whole (read expensive) large
wrench set.
One extremely valuable type of wrench is the adjustable wrench. An
adjustable wrench has a fixed upper jaw and a moveable lower jaw. The
lower jaw is moved by turning a threaded drum. The advantage of an
adjustable wrench is its ability to be adjusted to just about any size fastener.
The main drawback of an adjustable wrench is the lower jaw's tendency
to move slightly under heavy pressure. This can cause the wrench to slip if it
is not facing the right way. Pulling on an adjustable wrench in the proper
direction will cause the jaws to lock in place. Adjustable wrenches come in a
large range of sizes, measured by the wrench length.
PLIERS
See Figure 55
Pliers are simply mechanical fingers. They are, more than anything, an
extension of your hand. At least 3 pairs of pliers are an absolute necessity -
standard, needle nose and slip joint.
In addition to standard pliers there are the slip-joint, multi-position pliers
such as ChannelLockO3 pliers and locking pliers, such as Vise [email protected]
Slip joint pliers are extremely valuable in grasping oddly sized parts and
fasteners. Just make sure that you don't use them instead of a wrench too
often since they can easily round off a bolt head or nut.
Locking pliers are usually used for gripping bolts or studs that can't be
removed conventionally. You can get locking pliers in square jawed, needle-
nosed and pipe-jawed. Locking pliers can rank right up behind duct tape as
the handy-man's best friend.
SCREWDRIVERS
You can't have too many screwdrivers. They come in 2 basic flavors,
either standard or Phillips. Standard blades come in various sizes and
thickness for all types of slotted fasteners. Phillips screwdrivers come in
Fig; 50 Comparison of U.S. measure and metric wrench sizes
sizes with number designations from 1 on up, with the lower number Hacksaws have just one use -cutting things off. You may wonder why
designating the smaller size. Screwdrivers can be purchased separately or in you'd need one for something as simple as maintenance or repair, but you
sets. never know. Among other things, guide studs to ease parts installation can
be made from old bolts with their heads cut off.
HAMMERS
+ See Figure 56
You need a hammer for just about any kind of work. You need a ball-peen
hammer for most metal work when using drivers and other like tools. A
plastic hammer comes in handy for hitting things safely. A soft-faced dead-
blow hammer is used for hitting things safely and hard. Hammers are also
VERY useful with non air-powered impact drivers.
There are a lot of other tools that every DIYer will eventually need (though
not all for basic maintenance). They include:
9
Funnels
* Chisels
9
Punches
* Files
9
Hacksaw
* Portable Bench Vise
9
Tap and Die Set
Flashlight
Magnetic Bolt Retriever
Gasket scraper
9
Putty Knife
ScrewIBolt Extractors
9
Prybars
A tap and die set might be something you've never needed, but you will
eventually. It's a good rule, when everything is apart, to clean-up all threads,
on bolts, screws or threaded holes. Also, you'll likely run across a situation in
which you will encounter stripped threads. The tap and die set will handle
that for you.
Gasket scrapers are just what you'd think, tools made for scraping old
gasket material off of parts. You don't absolutely need one. Old gasket
material can be removed with a putty knife or single edge razor blade.
However, putty knives may not be sharp enough for some really stubborn
gaskets and razor blades have a knack of breaking just when you don't want
them to, inevitably slicing the nearest body part! As the old saying goes,
''always use the proper tool for the job". If you're going to use a razor to
scrape a gasket, be sure to always use a blade holder.
Putty knives really do have a use in a repair shop. Just because you
remove all the bolts from a component sealed with a gasket doesn't mean
it's going to come off. Most of the time, the gasket and sealer will hold it
tightly. Lightly inserting a putty knife at various points between the two parts
will break the seal without damage to the parts.
A small -8-10 in. (20-25cm) long -prybar is extremely useful for removing
stuck parts.
Never use a screwdriver as a prybar! Screwdrivers are not meant for
prying. Screwdrivers, used for prying, can break, sending the broken
shaft flying!
Screwlbolt extractors are used for removing broken bolts or studs that
have broken off flush with the surface of the part.
Fig. 52 Note how the flare wrench jaws are
Fig. 51 Always use a backup wrench to extended to grip the fitting tighter and Fig. 53 Several types and sizes of
prevent rounding flare nut fittings prevent rounding adjustable wrenches
I I I I
Fig. 54 You may find a nut that requires a 5 Pliers come in many shapes and Fig. 56 Three types of hammers. Top to
particularly large or small wrench (that is .You should have an assortment on bottom: ball peen, rubber dead-blow, and
plastic
+ See Figure 57
Almost every marine engine around today requires at least one special
tool to perform a certain task. In most cases, these tools are specially
designed to overcome some unique problem or to fit on some oddly sized
component.
When manufacturers go through the trouble of making a special tool, it is
usually necessary to use it to ensure that the job will be done right. A special
tool might be designed to make a job easier, or it might be used to keep you
from damaging or breaking a part.
Don't worry, MOST maintenance procedures can either be performed
without any special tools OR, because the tools must be used for such basic
things, they are commonly available for a reasonable price. It is usually just
the low production, highly specialized tools (like a super thin 7-point star-
shaped socket capable of 150 ft. Ibs. (203 Nm) of torque that is used only on
the crankshaft nut of the limited production what-dya-callit engine) that tend
to be outrageously expensive and hard to find. Hopefully, you will probably
never need such a tool.
Special tools can be as inexpensive and simple as an adjustable strap
wrench or as complicated as an ignition tester. A few common specialty tools
are listed here, but check with your dealer or with other boaters for help in
determining if there are any special tools for YOUR particular engine. There
is an added advantage in seeking advice from others, chances are they may
have already found the special tool you will need, and know how to get it
cheaper (or even let you borrow it).
BATTERY TESTERS
The best way to test a non-sealed battery is using a hydrometer to check
the specific gravity of the acid. Luckily, these are usually inexpensive and are
available at most parts stores. Just be careful because the larger testers are
usually designed for larger batteries and may require more acid than you will
be able to draw from the battery cell. Smaller testers (usually a short,
squeeze bulb type) will require less acid and should work on most batteries.
Electronic testers are available and are often necessary to tell if a sealed
battery is usable. Luckily, many parts stores have them on hand and are
willing to test your battery for you.
BATTERY CHARGERS
+ See Figure 58
If you are a weekend boater and take your boat out every week, then you
will most likely want to buy a battery charger to keep your battery fresh.
There are many types available, from low amperage trickle chargers to
electronically controlled battery maintenance tools that monitor the battery
voltage to prevent over or undercharging. This last type is especially useful if
you store your boat for any length of time (such as during the severe winter
months found in many Northern climates).
Even if you use your boat on a regular basis, you will eventually need a
battery charger. The charger should be used anytime the boat is going to be
in storage for more than a few weeks or so. Never leave the dock or loading
ramp without a battery that is fully charged.
Also, some smaller batteries are shipped dry and in a partial charged
state. Before placing a new battery of this type into service it must be filled
and properly charged. Failure to properly charge a battery (which was
shipped dry) before it is put into service will prevent it from ever reaching a
fully charged state.
MULTI-METERS (DVOMS)
See Figure 59
Multi-meters or Digital Volt Ohmmeter (DVOMs) are an extremely useful
tool for troubleshootina electrical ~roblems. Thev can be ourchased in either
analog or digital form and have aoprice range tosuit any budget. A multi-
meter is a voltmeter, ammeter and ohmmeter (along with other features)
combined into one instrument. It is often used when testing solid state
circuits because of its high input impedance (usually 10 mega-ohms or
more). A brief description of the multi-meter main test functions follows:
* Voltmeter -the voltmeter is used to measure voltage at any point in a
circuit or to measure the voltage drop across any part of a circuit. Voltmeters
usually have various scales and a selector switch to allow the reading of
different voltage ranges. The voltmeter has a positive and a negative lead.
To avoid the possibility of damage to the meter, whenever possible, connect
the negative lead to the negative (-) side of the circuit (to ground or nearest
the ground side of the circuit) and connect the positive lead to the positive
(t)side of the circuit (to the power source or the nearest power source).
Luckily, most quality DVOMs can adjust their own polarity internally and will
indicate (without damage) if the leads are reversed. Note that the negative
voltmeter lead will always be black and that the positive voltmeter will always
be some color other than black (usually red).
Ohmmeter -the ohmmeter is designed to read resistance (measured in
ohms) in a circuit or component. Most ohmmeters will have a selector switch
which permits the measurement of different ranges of resistance (usually the
selector switch allows the multiplication of the meter reading by 10, 100,
1,000 and 10,000). Some ohmmeters are "auto-ranging" which means the
meter itself will determine which scale to use. Since the meters are powered
by an internal battery, the ohmmeter can be used like a self-powered test
light. When the ohmmeter is connected, current from the ohmmeter flows
through the circuit or component being tested. Since the ohmmeter's internal
resistance and voltage are known values, the amount of current flow through
the meter depends on the resistance of the circuit or component being
tested. The ohmmeter can also be used to perform a continuity test for
suspected open circuits. In using the meterfor making continuity checks, do
not be concerned with the actual resistance readinas. Zero resistance. or
any ohm reading, indicates continuity in the circuit."lnfinite resistance '
indicates an opening in the circuit. A high resistance reading where there
Fig. 57 Almost every marine engine around today requires at least Fig. 58 The Battery Tendem is more than just a battery charger,
one special tool to perform a certain task when left connected, it keeps your battery fully charged
should be little or none indicates a problem in the circuit. Checks for short
circuits are made in the same manner as checks for open circuits, except
that the circuit must be isolated from both power and normal ground. Infinite
resistance indicates no continuity, while zero resistance indicates a dead
short.
Never use an ohmmeter to check the resistance of a component or wire
while there is voltage applied to the circuit.
Ammeter -an ammeter measures the amount of current flowing
through a circuit in units called amperes or amps. At normal operating
voltage, most circuits have a characteristic amount of amperes, called
'current draw" which can be measured using an ammeter. By referring to a
specified current draw rating, then measuring the amperes and comparing
the two values; one can determine what is happening within the circuit to aid
in diagnosis. An open circuit, for example, will not allow any current to flow,
so the ammeter reading will be zero. A damaged component or circuit will
have an increased current draw, so the reading will be high. The ammeter is
always connected in series with the circuit being tested. All of the current that
normally flows through the circuit must also flow through the ammeter; if
there is any other path for the current to follow, the ammeter reading will not
be accurate. The ammeter itself has very little resistance to current flow and,
therefore, will not affect the circuit, but, it will measure current draw only
when the circuit is closed and electricity is flowing. Excessive current draw
can blow fuses and drain the battery, while a reduced current draw can
cause motors to run slowly, lights to dim and other components to not
operate properly.
Fig. 59 Multi-meters, such as this one from UEI, are an extremely
useful tool for troubleshooting electrical problems
GAUGES
Compression Gauge
+ See Figure 60
An important element in checking the overall condition of your engine is to
check compression. This becomes increasingly more important on outboards
with high hours. Compression gauges are available as screw-in types and
hold-in types. The screw-in type is slower to use, but eliminates the
possibility of a faulty reading due to pressure escaping by the seal. A
compression reading will uncover many problems that can cause rough
running. Normally, these are not the sort of problems that can be cured by a
tune-up.
Vacuum Gauge
+ See Figures 61 thru 63
Vacuum gauges are handy for discovering air leaks, late ignition or valve
timing, and a number of other problems.
Eventually, you are going to have to measure something. To do this, you
will need at least a few precision tools.
MICROMETERS & CALIPERS
Micrometers and calipers are devices used to make extremely precise
measurements. The simple truth is that you really won't have the need for
many of these items just for routine maintenance. But, measuring tools, such
as an outside caliper can be handy during repairs. And, if you decide to
tackle a major overhaul, a micrometer will absolutely be necessary.
Fig. 60 Cylinder compression test results are extremely valuable
indicators of internal engine condition
Fig. 61 Vacuum gauges are useful for 1 1
troubleshooting including testing some fuel Fig. 62 You can also use the gauge on a Fig. 63 Hand-held vacuum/pressure pumps
Pumps hand-operated vacuum pump for tests are available at most parts stores
Should you decide on becoming more involved in boat engine mechanics,
such as repair or rebuilding, then these tools will become very important. The
success of any rebuild is dependent, to a great extent on the ability to check
the size and fit of components as specified by the manufacturer. These
measurements are often made in thousandths and ten-thousandths of an
inch.
Micrometers
+ See Figures 64 and 65
A micrometer is an instrument made up of a precisely machined spindle
that is rotated in a fixed nut, opening and closing the distance between the
end of the spindle and a fixed anvil. When measuring using a micrometer,
don't over-tighten the tool on the part as either the component or tool may be
damaged, and either way, an incorrect reading will result. Most micrometers
are equipped with some form of thumbwheel on the spindle that is designed
to freewheel over a certain light touch (automatically adjusting the spindle
and preventing it from over-tightening).
Outside micrometers can be used to check the thickness of parts such
shims or the outside diameter of components like the crankshaft journals.
They are also used during many rebuild and repair procedures to measure
the diameter of components such as the pistons. The most common type of
micrometer reads in 1/1000 of an inch. Micrometers that use a vernier scale
can estimate to 1/10 of an inch.
Inside micrometers are used to measure the distance between two
parallel surfaces. For example, in powerhead rebuilding work, the "inside
mike" measures cylinder bore wear and taper. Inside mikes are graduated
the same way as outside mikes and are read the same way as well.
Remember that an inside mike must be absolutely perpendicular to the
work bein0 measured. When you measure with an inside mike, rock the mike
gently from side to side and tip it back and forth slightly so that you span the
Fig. 64 Outside micrometers measure thickness, like shims or a
shaft diameter
widest part of the bore. Just to be on the safe side, take several readings. It
takes a certain amount of experience to work any mike with confidence.
Metric micrometers are read in the same way as inch micrometers, except
that the measurements are in millimeters. Each line on the main scale equals
Imm. Each fifth line is stamped 5, 10, 15 and so on. Each line on the thimble
scale equals 0.01 mm. It will take a little practice, but if you can read an inch
mike, you can read a metric mike.
Calipers
See Figures 66,67 and 68
Inside and outside calipers are useful devices to have if you need to
measure something quickly and absolute precise measurement is not
necessary. Simply take the reading and then hold the calipers on an
accurate steel rule. Calipers, like micrometers, will often contain a
thumbwheel to help ensure accurate measurement.
DIAL INDICATORS
See Figure 69
A dial indicator is a uauoe that utilizes a dial face and a needle to register
measurements. There is ahovable contact arm on the dial indicator. when
the arm moves, the needle rotates on the dial. Dial indicators are calibrated
to show readings in thousandths of an inch and typically, are used to
measure end-play and runout on various shafts and other components.
Dial indicators are quite easy to use, although they are relatively
expensive. A variety of mounting devices are available so that the indicator
can be used in a number of situations. Make certain that the contact arm is
always parallel to the movement of the work being measured,
Fig. 65 Be careful not to over-tighten the micrometers always use
the thumbwheel
Fig. 66 Calipers are the fast and easy way s can also be used to
to make precise measurements
TELESCOPING GAUGES
+ See Figure 70
A telescope gauge is really only used during rebuilding procedures (NOT
during basic maintenance or routine repairs) to measure the inside of bores.
It can take the piace of an inside mike for some of these jobs. Simply insert
the gauge in the hole to be measured and lock the plungers after they have
contacted the walls. Remove the tool and measure across the plungers with
an outside micrometer.
+ See Figures 72 and 73
Although there are a great variety of fasteners found in the modern boat
engine, the most commonly used retainer is the threaded fastener (nuts,
bolts, screws, studs, etc). Most threaded retainers may be reused, provided
that they are not damaged in use or during the repair.
@ Some retainers (such as stretch bolts or torque prevailing nuts) are
designed to deform when tightened or in use and should not be reused.
Whenever possible, we will note any special retainers which should be
replaced during a procedure. But you should always inspect the condition of
a retainer when it is removed and you should replace any that show signs of
damage. Check all threads for rust or corrosion that can increase the torque
necessary to achieve the desired clamp load for which that fastener was
originally selected. Additionally, be sure that the driver surface itself (on the
fastener) is not compromised from rounding or other damage. In some cases
a driver surface may become only partially rounded, allowing the driver to
catch in only one direction, in many of these occurrences, a fastener may be
installed and tightened, but the driver would not be able to grip and loosen
the fastener again. (This could lead to frustration down the line should that
component ever need to be disassembled again).
If you must replace a fastener, whether due to design or damage, you
must always be sure to use the proper replacement. In all cases, a retainer
of the same design, material and strength should be used. Markings on the
heads of most bolts will help determine the proper strength of the fastener.
The same material, thread and pitch must be selected to assure proper
hstaliation and safe operation of the motor afterwards.
Thread gauges are available to help measure a bolt or stud's thread. Most
part or hardware stores keep gauges available to help you select the proper
size. In a pinch, you can use another nut or bolt for a thread gauge. If the
bolt you are replacing is not too badly damaged, you can select a match by
finding another bolt that will thread in its place. If you find a nut that will
thread properly onto the damaged bolt, then use that nut as a gauge to help
se!ec?!k reolaceme~tbolt, If however, the bolt you are replacing is so badly
damaged (broken or drilled out) trial its threads cannot be used as a gauge,
you might start by looking for another bolt (from the same assembly or a
similar location) which will thread into the damaged bolt's mounting. If so, the
other bolt can be used to select a nut; the nut can then be used to select the
replacement bolt.
DEPTH GAUGES
@ See Figure 71
A depth gauge can be inserted into a bore or other small hole to
determine exactly how deep it is. One common use for a depth gauge is
measuring the distance the piston sits below the deck of the block at top
dead center. Some outside calipers contain a built-in depth gauge so you
can save money and buy just one tool.
Fig. 71 Depth gauges are used to measure
A -Length
B -Diameter (major diameter)
C -Threads per inch or mm
D -Thread length
E -Size of the wrench required
F -Root diameter (minor diameter)
Fig. 72 Threaded retainer sizes are determined using these
measurements
In all cases, be absolutely sure you have selected the proper
replacement. Don't be shy, you can always ask the store clerk for help.
Be aware that when you find a bolt with damaged threads, you may
also find the nut or tapped bore into which it was threaded has also
been damaged. If this is the case, you may have to drill and tap the
hole, replace the nut or otherwise repair the threads. Never try to force
a replacement bolt to fit into the damaged threads.
Torque is defined as the measurement of resistance to turning or rotating.
It tends to twist a body about an axis of rotation. A common example of this
would be tightening a threaded retainer such as a nut, bolt or screw.
Measuring torque is one of the most common ways to help assure that a
threaded retainer has been properly fastened.
When tightening a threaded fastener, torque is applied in three distinct
areas, the head, the bearing surface and the clamp load. About 50 percent of
Fig. 73 Thread gauges measure the threads-per-inch and the pitch
of a bolt or stud's threads
the measured torque is used in overcoming bearing friction. This is the
friction between the bearing surface of the bolt head, screw head or nut face
and the base material or washer (the surface on which the fastener is
rotating). Approximately 40 percent of the applied torque is used in
overcoming thread friction. This leaves only about 10 percent of the applied
torque to develop a useful clamp load (the force that holds a joint together).
This means that friction can account for as much as 90 percent of the
applied torque on a fastener.
Specifications are often used to help you determine the condition of
various components, or to assist you in their installation. Some of the most
common measurements include length (in. or cmlmm), torque (ft. Ibs., inch
Ibs. or Nm) and pressure (psi, in. Ha, kPa or mm Hq).
In some cases, that value may not be convenienily measured with what is
available in vour toolbox. Luckilv, manv of the measurina devices that are
available today will have two scales so US. or Metric &asurements may
easily be taken. If any of the various measuring tools that are available to
you do not contain the same scale as listed in your specifications, use the
conversion factors that are provided in the Specifications section to
determine the proper value.
The conversion factor chart is used by taking the given specification and
multiplying it by the necessary conversion factor. For instance, looking at the
first line, if you have a measurement in inches such as "free-play should be 2
in." but your ruler reads only in millimeters, multiply 2 in. by the conversion
factor of 25.4 to get the metric equivalent of 50.8mm. Likewise, if a
specification was given only in a Metric measurement, for example in
Newton Meters (Nm), then look at the center column first. If the
measurement is 100 Nm, multiply it by the conversion factor of 0.738 to get
73.8 ft. Ibs.
SAE Bolts
SAE Grade Number 1 or2 5 6 or 7
BoH Markings
Manufacturers' marks may
varydumber of lines
always two less than the
wade number. .,
I
Usage Frequent Frequent Infrequent
Bolt Size Maximum Maximum Maximum
(inches)Ñ(Thread Torque Torque Torque
Ft-Lb kgm Mm Ft-Lb kgm Nm Ft-Lb kgm Nm
'14-20 5 0.7 6.8 8 1.1 10.8 10 1.4 13.5 -28 6 0.8 8.1 10 1.4 13.6
Â¥'lie-1 11 1.5 14.9 17 2.3 23.0 19 2.6 25.8 -24 13 1.8 17.6 19 2.6 25.7
31a--16 18 2.5 24.4 31 4.3 42.0 34 4.7 46.0 -24 20 2.75 27.1 35 4.8 47.5
'116-14 28 3.8 37.0 49 6.8 66.4 55 7.6 74.5
-20 30 4.2 40.7 55 7.6 74.5
11z-13 39 5.4 52.8 75 10.4 101.7 85 11.75 115.2 -20 41 5.7 55.6 85 11.7 115.2
9/16-12 51 7.0 69.2 110 15.2 149.1 120 16.6 162.7
-18 55 7.6 74.5 120 16.6 182.7
'la-9 160 22.1 216.9 395 54.6 535.5 440 60.9 596.5
-14 175 24.2 237.2 435 60.1 589.7
1-8 236 32.5 318.6 590 81.6 799.9 660 91.3 894.8
-14 250 34.6 338.9 660 91.3 849.8
Metric Bolts
Relative Strength
Marking 4.6,4.8 8.8
olt r^
Usage Frequent Infrequent
Bolt Size Maximum Torque Maximum Torque
Thread Size x Pitch R-Lb Km Nm Ft-Lb KQ~ Nm
24 x 1.5 190-240 26.2-46.9 260-320 310-410 42.7-56.5 420-550
ANODES (ZINCS) ......................2.31
INSPECTION.........................2.33
LOCATION...........................2.31
SERVICING..........................2.33
BATTERIES...........................2.35
MAINTENANCE.......................2.35
STORAGE ...........................2.36
TESTING............................2.36
BOAT MAINTENANCE ..................2-35
BATTERIES .........................2.35
FIBERGLASS HULL ...................2.37
CLEARING A SUBMERGED MOTOR ......2-83
COMPRESSION TESTS .................2.39
COMPRESSION CHECK ...............2.39
OVERHAUL LEAKAGE CHECK ..........2.40
COOLING SYSTEM .....................2.14
FLUSHING...........................2.14
ENGINE COVER LATCHES ..............'2-5
RECOMMENDED LUBRICANT &
LUBRICATION.........................2.5
ENGINE COVERS ......................2.11
REMOVAL& INSTALLATION ............2.11
ENGINE IDENTIFICATION ................2.2
ENGINE MAINTENANCE ................2-11
ANODES (ZINCS) .....................2.31
COOLING SYSTEM ...................2.14
ENGINE COVERS ....................2.11
ENGINE OIL AND FILTER ..............2.16
FUEL& BREATHER LINES .............2.27
FUEL FILTER ........................2.23
GEARCASE (LOWER UNIT) OIL ........'2-21
JET DRIVE IMPELLER .................2.30
PROPELLER ........................2.27
TIMING BELT ........................2.34
ENGINE MOUNT CLAMP SCREWS .........2.5
LUBRICATION.........................2.5
RECOMMENDED LUBRICANT ...........2.5
ENGINE OIL AND FILTER ................2.16
CHANGE & FILTER SERVICE ...........2.19
CHECKING LEVEL ....................2.17
RECOMMENDATIONS.................2.16
FUEL& BREATHER LINES ...............2.27
FUEL FILTER ..........................2.23
HIGH.PRESSURE .....................2.25
LOW-PRESSURE.....................2.23
GEARCASE OIL .......................2.21
DRAINING& FILLING..................2.22
LEVEL& CONDITION..................2.22
OIL RECOMMENDATIONS ..............2.21
GENERAL INFORMATION ...............'2-2
BEFOREIAFTER EACH USE .............2.3
ENGINE IDENTIFICATION ...............2.2
MAINTENANCE COVERAGE ............2.2
MAINTENANCE EQUALS SAFETY ........2.2
OUTBOARDS ON SAIL BOATS ...........2.2
JET DRIVE BEARING ...................2.10
GREASE REPLACEMENT ..............2.10
LUBRICATION........................2.10
RECOMMENDED LUBRICANT ..........2.10
JET DRIVE IMPELLER ..................2.30
CLEARANCE.........................2.30
GENERAL INFORMATION ..............2.30
INSPECTION.........................2.30
LINKAGE, CABLES AND SHAFTS ..........2.5
LUBRICATION.........................2.5
RECOMMENDED LUBRICANT ...........2.5
LOWER UNIT OIL ......................2.21
DRAINING & FILLING..................2.22
LEVEL& CONDITION..................2.22
OIL RECOMMENDATIONS ..............2.21
LUBRICATION SERVICE .................2-5
ENGINE COVER LATCHES ..............2.5
ENGINE MOUNT CLAMP SCREWS .......2.5
JET DRIVE BEARING .................2.10
LINKAGE. CABLES AND SHAFTS ........2.5
POWER TRIMITILT RESERVOIR .........2.5
PROPELLER SHAFT ..................2.10
STEERINGISWIVEL BRACKET ...........2.9
TILT BRACKET ........................2.9
OIL AND FILTER .......................2.16
CHANGE & FILTER SERVICE ...........2.19
CHECKING LEVEL ....................2.17
RECOMMENDATIONS.................2.16
POWER TRIMILT RESERVOIR ...........2.5
FLUID LEVEL .........................2.5
RECOMMENDED LUBRICANT ...........2.5
PROPELLER .........................'2-27
INSPECTION.........................2.27
REMOVAL& INSTALLATION ............2.27
PROPELLER SHAFT ....................2.10
LUBRICATION.......................$2-10
RECOMMENDED LUBRICANT ..........2.10
RE.COMMISSIONING ...................2.82
REMOVAL FROM STORAGE ............2.82
SPARK PLUG WIRES ...................2.44
REMOVAL& INSTALLATION ............2.45
TESTING............................2.45
SPARK PLUGS ........................2.40
HEAT RANGE ........................2.41
INSPECTION& GAPPING ..............2.43
READING PLUGS .....................2.43
REMOVAL& INSTALLATION ............2.41
SPECIFICATIONS......................2.84
CAPACITIES .........................2.87
GENERAL ENGINE ....................2.84
GENERAL ENGINE SYSTEM ............2.85
MAINTENANCE INTERVALS ............2.86
TUNE.UP ............................2.88
VALVE CLEARANCE ...................2.90
STEERINGISWIVEL BRACKET ............2.9
LUBRICATION.........................2.9
RECOMMENDED LUBRICANT ...........2.9
STORAGE (WHAT TO DO
BEFORE AND AFTER) ..................2.79
RE-COMMISSIONING.................2.82
WINTERIZATION .....................2.79
TILT BRACKET .........................2.9
LUBRICATION.........................2.9
RECOMMENDED LUBRICANT ...........2.9
TIMING AND SYNCHRONIZATION .........2.46
2.5 HP MOTORS .....................2.47
41516 HP (1 38CC) MOTORS ............2.48
9.9115 HP MOTORS ...................2.49
25 HP V2 MOTORS ...................2.52
25/30 HP (3-CYL) MOTORS ............2.53
40150 HP MOTORS ...................2.57
60170 HP MOTORS ...................2.58
9011 15/140 HP MOTORS ...............2.59
150/140 HP MOTORS .................2.61
200/225/250 HP MOTORS ..............2.62
300 HP MOTORS .....................2.63
TIMING BELT ..........................2.34
INSPECTON .........................2.34
TUNE.UP .............................2.38
COMPRESSION TESTS ...............2.39
ELECTRONIC IGNITION SYSTEMS ......2.46
INTRODUCTION TO TUNE.UPS .........2.38
SPARK PLUG WIRES .................2.44
SPARK PLUGS .......................2.40
TUNE-UP SEQUENCE .................2.38
TUNE-UP SEQUENCE ..................2.38
VALVE CLEARANCE ....................2.64
VALVE LASH ........................2.64
VALVE LASH ADJUSTMENT ..............2.64
2.5.6 HP.............................2.64
9.9115 HP ............................2.65
25 HPV2 ............................2.66
25/30 HP (3-CYL) .....................2.67
40150 HP ............................2.67
60170 HP ............................2.70
9011151140 HP ........................2.71
1 501175 HP ..........................2.73
200-300 HP V6 .......................2.76
WINTERIZATION.......................2.79
PREPPING FOR STORAGE .............2.80
In the past, we at Seloc have estimated that some 75% of engine repair
work can be directly or indirectly attributed to lack of proper care for the
engine. This is especially true of care during the off-season period. There is
no way on this green earth for a mechanical engine, particularly an outboard
motor, to be left sitting idle for an extended period of time, say for four to six
months, and then be ready for instant satisfactory service.
Imagine, if you will, leaving your car or truck for six months, and then
expecting to turn the key, having it roar to life, and being able to drive off in
the same manner as a daily occurrence.
Therefore it is critical for an outboard engine to either be run (at least
once a month), preferably, in the water and properly maintained between
uses OR for it to be specifically prepared for storage and serviced again
immediately before the start of the season.
Only through a regular maintenance program can the owner expect to
receive long life and satisfactory performance at minimum cost.
Many times, if an outboard is not performing properly, the owner will
"nurse" it throuah the season with aood intentions of workino on the unit
once it is no longer being used. ~swith many New Year's r&olutions, the
good intentions are not completed and the outboard may lie for many months
before the work is begun or the unit is taken to the marine shop for repair.
Imagine, if you will, the cause of the problem being a blown head gasket.
And let us assume water has found its way into a cylinder. This water,
allowed to remain over a long period of time, will do considerably more
damage than it would have if the unit had been disassembled and the repair
work performed immediately. Therefore, if an outboard is not functioning
properly, do not stow it away with promises to get at it when you get time,
because the work and expense will only get worse, the longer corrective
action is postponed. In the example of the blown head gasket, a relatively
simple and inexpensive repair job could very well develop into major
overhaul and rebuild work.
OK, perhaps no one thing that we do as boaters will protect us from risks
involved with enjoying the wind and the water on a powerboat. But, each
time we perform maintenance on our boat or motor, we increase the
likelihood that we will find a potential hazard before it becomes a problem.
Each time we inspect our boat and motor, we decrease the possibility that it
could leave us stranded on the water.
In this way, performing boat and engine service is one of the most
important ways that we, as boaters, can help protect ourselves, our boats,
and the friends and family that we bring aboard.
Owners of sailboats pride themselves in their ability to use the wind to
clear a harbor or for movement from Port A to Port B, or maybe just for a day
sail on a lake. For some, the outboard is carried only as a last resort -in
case the wind fails completely, or in an emergency situation or for ease of
docking.
Therefore, in some cases, the outboard is stowed below, usually in a very
poorly ventilated area, and subjected to moisture and stale air -in short, an
excellent environment for "sweating" and corrosion.
If the owner could just take the time at least once every month, to pull out
the outboard, clean it up, and give it a short run, not only would helshe have
peace of mind" knowing it will start in an emergency, but also maintenance
costs will be drastically reduced.
At Seloc, we strongly feel that every boat owner should pay close
attention to this section. We also know that it is one of the most frequently
used portions of our manuals. The material in this section is divided into
sections to help simplify the process of maintenance. Be sure to read and
thoroughly understand the various tasks that are necessary to keep your
outboard in tip-top shape.
Topics covered in this section include:
1. General Information (What Everyone Should Know About
Maintenance) -an introduction to the benefits and need for proper
maintenance. A guide to tasks that should be performed before and after
each use.
2. Lubrication Service -after the basic inspections that you should
perform each time the motor is used, the most frequent form of periodic
maintenance you will conduct will be the Lubrication Service. This section
takes you through each of the various steps you must take to keep corrosion
from slowly destroying your motor before your very eyes.
3. Engine Maintenance -the various procedures that must be
performed on a regular basis in order to keep the motor and all of its various
systems operating properly.
4. Boat Maintenance -the various procedures that must be performed
on a regular basis in order to keep the boat hull and its accessories looking
and working like new.
5. Tune-up -also known as the pre-season tune-up, but don't let the
name fool you. A complete tune-up is the best way to determine the
condition of your outboard while also preparing it for hours and hours of
hopefully trouble-free enjoyment.
6. Winter Storage and Spring Commissioning Checklists -use these
sections to guide you through the various parts of boat and motor
maintenance that protect your valued boat through periods of storage and
return it to operating condition when it is time to use it again.
7. Specification Charts -located at the end of the section are quick-
reference, easy to read charts that provide you with critical information such
as General Engine Specifications, Maintenance Intervals, Lubrication Service
(intervals and lubricant types) and Capacities.
EXPLODED VIEWS
There are so many potential exploded views for any given engine family
that it can be difficult to make sure they are all included. Many times a given
factory source of information does not even contain all of them.
But here is a hint. For nearly a decade Johnson has been selling
REBADGED Suzuki 4-stroke motors. And as of the authoring of this
information JohnsonIBombardier has links to their parts catalogs on the
www.johnson.com and www.evinrude.com websites (under service
literaturelengine diagrams in the accessory section) so on any motor that
was also sold as a Johnson 4-stroke, you can reference additional exploded
views for free anytime on their website.
See Figures 1thru 4
Throughout this guide we will make reference to motors the easiest way
possible. Unlike some other manufacturers who like to make multiple
powerhead configurations in overlapping hp ranges, Suzuki has thankfully
approached their model line with much more logic.
For that reason we will probably MOST often reference motors simply by
the HP, though we'll usually list all hp models of a given family at the same
time, so for example, not just the 4 hp single-cylinder motor, but the 41516 hp
motors (as they are all built on the same platform and will likely share MOST
procedures). Or for another example toward the other end of the hp
spectrum the 20012251250 hp motors.
In other cases we may make reference to all motors with a given feature,
like all Carbureted motors (meaning all 30 hp or smaller) or all EFI motors
(meaning 40 hp or larger). Or we may say all remote control models, all tiller
control models, all models with Power Trimnilt (PTT) etc.
To help with proper engine identification, all of the engines covered by this
manual are listed in the General Engine and General Engine System
Specifications charts at the end of this section. In these charts, the engines
are listed with their respective engine families, by horsepower rating, number
of cylinders, engine type (No. of cylinder, inline or V), years of production
and displacement (cubic inches and cubic centimeters or CCs). Basically
they are listed by all of the different ways we might sort or identify them
throughout this repair guide.
Suzuki tends to limit year-to-year changes on their models (we're not
saying they don't make changes, because they do, but they don't TEND to
make a LOT of changes). Still, when it comes time to order replacement
parts (or to follow a given procedure that is divided by model years) it is
critical that you know the correct MODEL YEAR for the motor on which you
are working. Or in a few cases, the mid-year model break (but these are
pretty few and far between).
Either way, don't just trust the paperwork for the motor or boat and when it
was sold, since it is not uncommon for motors to be manufactured a year
before they are sold, or even to sit around in crates a couple of years before
finding their way onto a boat. Start the identification of an outboard with the
MODEL CODE found on the Serial NumberIModel Number tag on the
transom bracket. A code is usually found on the top right of the ID tag (to the
right of the model name) which is translated as follows:
*
1995: S
*
1995:T
5
1995: V
*
1995:W
*
1995: X
*
2000: Y
5
2001: K1
2002: K2
2003: K3
2004: K4
2005: K5
2006: K6
8
2007: K7
But not all model code tags may be equipped with the model year ID so
you need other ways of identifying the motor as well. A second method
would be to copy down the Model Identification Number (the first set of
numbers and letters on the Model ID tag, which are BELOW the SUZUKI
badge and the Model ID. This identification number is separated from the
individual motor serial number by a hyphen ("-,I). Bring this ID number to your
parts supplier or a Suzuki dealer and they may be able to help confirm your
model year.
Lastly, most models sold in the US are also equipped with an Emissions
Control Information label as well. When eaui~~ed
this label dives basic tune-
UD or calibration information including
,
.,
5
Model Family Name
Fig. 1 A model ID tag is normally found on the side of the transom
bracket (usually starboard side)
*
Displacement (cc's)
*
Advertised Power Output (kW)
Recommended fuel
* Tune-up Conditions (Normal Operating Temperature, Shifter in Neutral,
etc.)
*
Ignition Timing (degrees ATDC or BTDC)
Idle Speed (rpm)
But perhaps the most useful feature on the Emission Control Information
label is a confirmation of what year emissions standards the motor was
produced to meet, meaning what MODEL YEAR for which was the motor
designed.
You should ALWAYS check for an emission control label and go with
the specifications on it before you believe anything in print or on the
web. This label may contain running changes which never made it to
published information from Suzuki or any other company.
The emissions control information label may reflect changes that are
made during production runs and are often not later reflected in a company's
service literature. For this reason, specifications on the label always
supersede those of a print manual.
As stated earlier, the best means of extending engine life and helping to
protect yourself while on the water is to pay close attention to boaffengine
maintenance. This starts with an inspection of systems and components
before and after each time you use your boat.
A list of checks, inspections or required maintenance can be found in the
Maintenance Intervals Chart at the end of this section. Some of these
inspections or tasks are performed before the boat is launched, some only
after it is retrieved and the rest, both times.
VISUALLY INSPECTING THE BOAT AND MOTOR
@ See Figures 5 and 6
Both before each launch and immediately after each retrieval, visually
inspect the boat and motor as follows:
1. Check the fuel and oil levels according to the procedures in this
manual. Do NOT launch a boat without properly topped off fuel tank and
proper crankcase oil level. It is not worth the risk of getting stranded or of
damage to the motor. Likewise, upon retrieval, check the oil and fuel levels
while it is still fresh in your mind. This is a good way to track fuel
consumption (one indication of engine performance). Oil consumption should
be minimal, but all 4-stroke engines allow a small portion of oil to burn.
Watch for sudden increases in the amount of oil burned and investigate
further if found.
Fig. 2 The model ID tag normally contains Fig. 3 For US motors, the Emissions Fig. 4 The Emissions Control Information
information such as the model name, year,
model indicator number and individual
Control Information label can also be used
to identify year (as well as confirm specific
label is normally found on the manual
starter or flywheel cover (as applicable) on
Fig. 5 Rope and fishing line entangled behind the propeller can cut
through the seal, allowing water to enter and lubricant to escape
2. Check for sians of fuel or oil leakaae. Probabiv as imoortant as
making sure enoughfuel and oil is onboard, the need to make sure that no
dangerous conditions might arise due to leaks. Thoroughly check all hoses,
fittings and tanks for signs of leakage. Oil leaks may cause the boat to
become stranded, or worse, could destroy the motor if undetected for a
significant amount of time. Fuel leaks can cause a fire hazard, or worse, an
explosive condition. This check is not only about properly maintaining your
boat and motor, but about helping to protect your life.
3. Inspect the boat hull and engine cases for signs of corrosion or
damage. Don't launch a damaged boat or motor. And don't surprise yourself
dockside or at the launch ramp by discovering damage that went unnoticed
last time the boat was retrieved. Repair any hull or case damage now.
4. Check the battery connections to make sure they are clean and
tight. A loose or corroded connection will cause charging problems
(damaging the system or preventing charging). There's only one thing worse
than a dead battery dockside/launch ramp and that's a dead battery in the
middle of a bay, river or worse, the ocean. Whenever possible, make a quick
visual check of battery electrolyte levels (keeping an eye on the level will
give some warning of overcharging problems). This is especially true if the
engine is operated at high speeds for extended periods of time.
5. Check the propeller and gearcase. Make sure the propeller shows
no signs of damage. A broken or bent propeller may allow the engine to
over-rev and it will certainly waste fuel. The gearcase should be checked
before and after each use for signs of leakage. Check the gearcase oil for
signs of contamination if any leakage is noted. Also, visually check behind
the propeller for signs of entangled rope or fishing lines that could cut
through the lower gearcase propeller shaft seal. This is a common cause of
gearcase lubricantleakage, and eventually, water contamination that can
lead to aearcase failure. Even if no aearcase leakaae is noted when the boat
is first retrieved, check again next time before launching. A nicked seal might
c:seep fluid right away when still swollen from heat immediately after use,
but might begin seeping over the next day, week or month as it sat, cooled
and dried out.
6. Check all accessible fasteners for tightness. Make sure all easily
accessible fasteners appear to be tiaht. This is especially true for the
propeiler nut, any anode retaining bolts, all steering or throttle linkage
fasteners and the engine clamps or mounting bolts. Don't risk loosing control
or becoming stranded due to loose fasteners. Perform these checks before
heading out, and immediately after you return (so you'll know if anything
needs to be sewiced before you want to launch again.)
7. Check operation of all controls including the throttlelshifter,
steering and emergency stoplstart switch andlor safety lanyard. Before
launching, make sure that all linkage and steering components operate
properly and move smoothly through their range of motion. All electrical
Fig. 6 Always make sure the transom plug is installed and
tightened securely before a launch
switches (such as power trimltiit) and especially the emergency stop
system(s) must be in proper working order. While underway, watch for signs
that a system is not working or has become damaged. With the steering,
shifter or throttle, keep a watchful eye out for a change in resistance or the
start of jerkylnotchy movement.
8. Check the water pump intake grate and water indicator. The
water pump intake grate should be clean and undamaged before setting out.
Remember that a damaged grate could allow debris into the system that
could destroy the impeller or clog cooling passages. Once underway, make
sure the cooling indicator stream is visible at all times. Make periodic checks,
including one final check before the motor is shut down each time. If a
cooling indicator stream is not present at any point, troubleshoot the problem
before further engine operation.
9. If used in salt, brackish or polluted waters thoroughly rinse the
engine (and hull) after use, then flush the cooling system according to
the procedure in this section.
10. Visually inspect all anodes after each use for signs of wear,
damage or to make sure they just plain didn't fail oft (especially if you weren't
careful about checking all the accessible fasteners the last time you
launched).
11. On EFI models, be sure to shut the battery switch off if the
engine is not going to be run for a couple of weeks or more. The Engine
Control Unit (ECU) on fuel-injected motors covered by this manual will
continue to draw a small amount of current from the battery, even when the
motor is shut off. In order to prevent a slow drain of the entire battery, either
periodically recharge the battery, or isolate it by disconnecting the cables or
shutting off the battery switch when the boat is dockside or on the trailer.
If the boat is not equipped with a battery switch, you can always
locate and remove the ECU fuse (usually found in a separate fuse
holder) found on the side of the engine. Of course, if this is done, tape
the fuse to an obvious point so it will be installed before the next
attempt to start the motor. This could save some embarrassing and
frustrating troubleshooting time if the fact that it was removed
becomes lost in your memory.
12. For Pete's sake, make sure the plug is in! We shouldn't have to
say it, but unfortunately we do. If you've been boating for any length of time,
you've seen or heard of someone whose backed a trailer down a launch
ramp, forgetting to check the transom drain plug before submerging (literally)
the boat. Always make sure the transom plug is installed and tight before a
launch.
An outboard motor's greatest enemy is corrosion. Face it, oil and water
just don't mix (well, you CAN mix them with some heat but you tend to get a
grey waste water-like substance) and, as anyone who has visited a junkyard
knows, metal and water aren't the greatest of friends either. To expose an
engine to a harsh marine environment of water and wind is to expect that
these elements will take their toll over time. But, there is a way to fight back
and help prevent the natural process of corrosion that will destroy your
beloved boat motor.
Various marine grade lubricants are available that serve two important
functions in preserving your motor. Lubricants reduce friction on metal-to-
metal contact surfaces and, they also displace air and moisture, therefore
slowing or preventing corrosion damage. Periodic lubrication services are
your best method of preserving an outboard motor.
Lubrication takes place through various forms. For all engines, internal
moving parts are lubricated by engine oil contained in the engine crankcase
and pumped through oil passages. The gear oil and crankcase oil should be
periodically checked and replaced following the appropriate Engine
Maintenance procedures. Perform these services based on time or engine
use, as outlined in the Maintenance Intervals chart at the end of this section.
For motors equipped with power trimltilt, the fluid level and condition in
the reservoir should be checked periodically to ensure proper operation.
Also, on these motors, correct fluid level is necessary to ensure operation of
the motor impact protection system.
When equipped with power trimltilt, proper fluid level is necessary for
the built-in impact protection system. Incorrect fluid level could lead to
significant gearcase damage in the event of an impact.
Most other forms of lubrication occur through the application of grease
(such as Suzuki's Water Resistant Grease, an Anti-Corrosion Spray or their
equivalents) to various points on the motor. These lubricants are either
applied by hand (an old toothbrush can be helpful in preventing a mess) or
using a grease gun to pump the lubricant into grease fittings (also known as
zerk fittings). When using a grease gun, do not pump excessive amounts of
grease into the fitting. Unless otherwise directed, pump until either the rubber
seal (if used) begins to expand or until the grease just begins to seep from
the joints of the component being lubricated (if no seal is used).
To ensure your motor is getting the protection it needs, perform a visual
inspection of the various lubrication points at least once a week during
regular seasonal operation (this assumes that the motor is being used at
least once a week). Follow the recommendations given in the Maintenance
Intervals Chart at the end of this section and perform the various lubricating
services at least every 3 months or 50 hours. We said at least meaning you
should perform these services more often, as discovered by your weekly
inspections.
RECOMMENDED LUBRICANT & LUBRICATION
Though Suzuki factory literature does not mention the periodic lubrication
of the engine cover latches we still think this is a wise thing to do.
Use either Suzuki Water Resistant Grease for easily accessed areas, or a
spray lubelcorrosion protectant on hard to access areas.
Depending on the latch type, either apply a small amount of grease to the
metal surfaces using an applicator brush andlor spray lube, then work the
latch back and forth a couple of times to make sure it evenly spread.
6 See Figure 7
RECOMMENDED LUBRICANT
Use Suzuki Water Resistant Grease, or an equivalent marine grease for
lubrication.
LUBRICATION
+ See Figure 7
Many of the models covered by this manual are designed to be portable
or permanently installed. Although installation and rigging will vary, the
threads of the engine mount clamp screws should be lubricated periodically
to prevent them from corroding in place. Apply a light coating of a suitable
marine grease to the threads of both clamp screws. If necessary, apply the
grease and loosen the clamp to ensure the grease is drawn through the
threaded portion of the bracket, then retighten the clamp and repeat for the
remaining clamp. When you are finished, be certain that the clamps are
properly tightened. Also, pay extra attention to the clamps before and after
the next use, to make sure they remain tightened.
See Figure 8
When equipped with power trimltilt, proper fluid level is necessary for
the built-in impact protection system. Incorrect fluid level could lead to
significant gearcase damage in the event of an impact.
RECOMMENDED LUBRICANT
The power tridtilt reservoir must be kept full of Suzuki Power Trim and
Tilt Fluid OR Dexron illAutomatic Transmission Fluid.
CHECKING FLUID LEVEUCONDITION
See Figure 8
The fluid in the power tridtilt reservoir should be checked periodically to
ensure it is full and is not contaminated. To check the fluid, tilt the motor
upward to the full tilt position, then manually engage the tilt support for safety
and to prevent damage. Remove the filler cap (they are usually threaded in
position) and make a visual inspection of the fluid. It should seem clear and
not milky. The level is proper if, with the motor at full tilt, the level is even
with the bottom of the filler cap hole.
RECOMMENDED LUBRICANT
Use Suzuki Water Resistant Grease, or an equivalent marine grease for
lubrication.
LUBRICATION
@ See Figures 9 thru 35
Every Suzuki outboard uses some combination of cables andlor linkage in
order to actuate the throttle plate (of the carburetor, carburetors or throttle
body), the gearcase shifter and, on some smaller carbureted motors, the
choke plate. Because linkage and cables contain moving parts that work in
contact with other moving parts, the contact points can become worn and
loose if proper lubrication is not maintained. These small parts are also
susceptible to corrosion and breakage if they are not protected from moisture
by light coatings of grease. Periodically apply a light coating of suitable water
resistant marine grease on each of these surfaces where either two moving
parts meet or where a cable end enters a housing. Make sure all sliding,
rotating or contact surfaces of the linkage are coated. For more details on
grease points refer to the accompanying illustrations.
2-6 MAINTENANCE AND TUNE-UP
Fig. 7 Apply lubricant to the threads on the
engine mount clamps
Fig. 8 Trimltilt fluid level is important to
protecting the engine in case of an impact
Fig. 9 Rotating and sliding parts on the
underside of the tiller arm (on tiller control
models) should be greased
Fig. 11 ..springs and/or linkage for the
Fig. 10 Be sure to grease any cables. . . Neutral Start Interlock cables on manual Fig. 12 The shift cablesllinkage should be
Fig. 13 Don't forget all carburetor, choke Fig. 14 Throttle cable lubrication -2.5 hp Fig. 15 Be sure to grease the shift lever at
andlor throttle body linkages motors the rotation point- 41516 hp motors
Carburetor linkage
w
Fig. 16 Throttle linkage lubrication -41516 hp Fig. 17 Shift lever lubrication -41516 hp Fig. 18 Carburetor linkage -9.9115 hp
motors motors motors thru 2002
Carburetor linkage
Fig. 19 Carburetor linkage -2003-04 9.9115 Fig. 20 Carburetor linkage -2005 and later Fig. 21 Throttle cable -Tiller control 9.9115
hp motors 9.9115 hp motors hp motors
Fig. 22 Neutral Starter Interlock (NSI) cable -tarter Interlock (NSI) cable -Fig. 24 Throttle cable at powerhead linkage
9.9115 hp motors -25 hp V2 motors
Fig. 25 Throttle cable at tiller bracket -25 hp Fig. 26 Throttle linkage -25/30hp (3-cyl) Fig. 27 Throttle linkage (additional points
V2 motors motors (Remote shown, Tiller similar)
1 1
1 1
Throffle1 shiftlinkage
Fig. 28 Shift and throttle linkage -40150 hp Fig. 29 Shift and throttle linkage -60170hp
motors motors
Fig. 31 Throttle body cable -150/175hp Fig. 32 Shift and throttle linkage -1501175 Fig. 33 Throttle cable and drum -
motors hp motors 20012251250hp motors
Fig. 34 Throttle cable and throttlelshift linkage -20012251250 hp
motors
RECOMMENDED LUBRICANT
Use Suzuki Water Resistant Grease, or an equivalent marine grease for
lubrication.
LUBRICATION
-
+ See Figures 36 thru 40
Most motors covered by this manual are equipped with at least one
grease fitting on the gearcase swivel bracket, though some may equipped
with 2 or more. Fittings are usually on the port or starboard side (except for
some of the smaller motors like the 41516 hp models, where they are
mounted facing straight back from the bracket).
On all models equipped with a fitting, use a grease gun to apply fresh
water resistant marine grease until a small amount of lubricant begins to
seep from the swivel bracket. It is important to keep this system corrosion
free in order to prevent corrosion that would lead to excessive resistance or
even binding that might cause dangerous operational conditions.
RECOMMENDED LUBRICANT
Use Suzuki Water Resistant Grease, or an equivalent marine grease for
lubrication.
LUBRICATION
See Figure 41
Every Suzuki outboard, 4 hp and larger, uses 2 zerk fittings on the
forward side of the tilt bracket in order to provide grease to the tilt assembly.
Be sure to apply a water resistant marine grade grease to the fitting(s) until a
small amount of grease seeps from the joints. Also, on manual tilt modeis,
apply grease to the tilt lever and/or pin and any other metal-to-metal friction
surfaces. All models will usually have some form of tilfftrailering bracket
assembly which should also be greased at pivot and contact points. Applying
grease will prevent corrosion while also ensuring smooth operation. To make
sure all surfaces are covered, apply grease with the motor in both the full tilt
and full downward positions.
Fig. 38 Some of the smallest models (like
Fig. 36 Most models contain at least one the 41516 hp) may have a fitting at the rear
center of the housing. . .
Fig. 39 . ..or they may have one of more Fig. 40 View of the grease fitting on a 9.9115 Fig. 41 Every model, 4 hp and above, has 2
fittings up near the steering friction knob hp outboard zerk fittings on the tilt bracket assembly
RECOMMENDED LUBRICANT
Use Suzuki Water Resistant Grease, or an equivalent marine grease for
lubrication.
PROP SHAFT LUBRICATION
+ See Figure 42
One of the most common preventable problems in boating is when the
propeller hub becomes corroded (frozen) to the propeller shaft. When this
occurs the propeller and/or the gearcase is often damaged in the process of
trying to separate them. For this reason AT LEAST seasonally, but MUCH
MORE OFTEN (at least every 50 hours13 months) if the boat is used often in
salt water or stored in salt water, the propeller should be removed so a light
coating of water resistant grease can be added to the shaft splines. This
coating will help prevent the propeller from becoming corroded onto the
shaft.
For more details on propeller service, please refer to Propeller, later in
this section.
RECOMMENDED LUBRICANT
See Figure 43
Jet drive models covered here require special attention to ensure that the
driveshaft bearing remains properly lubricated.
After each day of use, the jet drive bearing should be properly lubricated
using a grease gun. Also, after every 30 hours of fresh water operation or
every 15 hours of salt/brackish/polluted water operation, the drive bearing
grease must be replaced. Follow the appropriate procedure:
Use Suzuki Water Resistant grease or equivalent water resistant NLGI
No. 1 lubricant.
DAILY BEARING LUBRICATION
+ See Figures 44 and 45
A grease fitting is located under a vent hose on the lower port side of the
jet drive. Disconnect the nose from the fitting, then use a grease gun to apply
enough grease to the fitting to just fill the vent hose. Pump grease into the
Fig. 42 A light coating of marine grade grease should prevent the
nrooeller hub from seizina on the shaft
fitting until any moisture is displaced and the old grease just starts to come
out from the passages through the hose coupling and then reconnect the
hose to the fitting.
@ Do not attempt to just grasp the vent hose and pull, as it is a tight fit
and when it does come off, you'll probably go flying if you didn't
prepare for it. The easier method of removing the vent hose from the
fitting is to deflect the hose to one side and snap it free from the fitting.
GREASE REPLACEMENT
+ See Figures 44,45 and 46
A grease fitting is located under a vent hose on the lower port side of the
jet drive. This grease fitting is utilized at the end of each day's use to add
fresh grease to the jet drive bearing. But, every 30 or 15 days (depending if
use is in fresh or salUbrackish1polluted waters), the grease should be
completely replaced. This is very similar to the daily greasing, except that a
lot more grease it used. Disconnect the hose from the fitting (by deflecting it
to the side until it snaps free from the fitting), and use a grease gun to apply
enough grease to the fitting until grease exiting the assembly fills the vent
NANCE AND TUNE-U
1 Fig. 43 Jet drive models reauire lubrication
ofthe bearing after each day of use, a label Fig. 44 The jet drive lubrication fitting is Fig. 45 Attach a grease gun to the fitting for
on the housing usually reminds the owner found under the vent hose lubrication
hose. Then, continue to pump grease into the fitting to force out all of the old
grease (you can tell this has been accomplished when fresh grease starts to
come out of the vent instead of old grease, which will be slightly darker due
to minor contamination from normal use). When nothing but fresh grease
comes out of the vent the fresh grease has completely displaced the old
grease and you are finished. Be sure to securely connect the vent hose to
the fitting.
Each time this is performed, inspect the grease for signs of excessive
moisture contamination or discoloration. A gradual increase in moisture
content over a few services is a sign of seal wear that is beginning to allow
some seepage. Very dark or dirty grease may indicate a worn seal (inspect
andlor replace the seal, as necessary to prevent severe engine damage
should the seal fail completely).
H Keep in mind that some discoloration of the grease is expected
when a new seal is broken-in. The discoloration should go away
gradually after one or two additional grease replacement services.
Whenever the jet drive bearing grease is replaced, take a few minutes to
apply some of that same water-resistant marine grease to the pivot points of
the jet linkage.
REMOVAL & INSTALLATION
See Figures 47 thru 57
Removal of the top cover is necessary for the most basic of maintenance
and inspection procedures. The cover should come oft before and after each
use in order to perform these basic safety checks. The lower covers do not
need to be removed nearly as often, but on models where they are easily
removed, they should be removed at least seasonally for service and
inspection procedures. Don't let a small leak or damaged cablethose hide
behind the safety of a cover.
On all models, the engine top cover is attached by some type of lever or
latch. No tools are necessary to remove the cover itself. The exact shape
and design of the levers vary somewhat from model-to-model, though they
are usually located on the forwardtaft parts of the motor, at the split line
between the top cover and the lower cases.
Many of the smaller motors use a single over-center latch that is pulled
outward on the bottom of the latch to give it enough room for the top of the
latch to release from the cover. While most of the larger motors use rotating
latches that hook onto tabs on the top cover, these are normally released
pivoting the lever downward.
No matter what design is used, be certain that the cover is fully seated
and mounted tightly to the lower cases in order to prevent the possibility of it
coming loose in service,
Fig. 46 Coat the pivot points of the jet linkage with grease
periodically
H On models with a rope starter, the rope handle fits through a
grommet in the top cover so that the cover must be pulled slightly
forward before it is lifted too far upward to remove it as the handle is
gently fed through the grommet.
The lower covers of most motors are screwed or bolted together by
fasteners found around the perimeter of one or both sides of the cover. In a
few cases, and we'll note them whenever possible, one or more of the
fasteners may be hidden.
Cover screws on Suzuki outboards are usually of the Phillips or
Slotted head types.
A few of the smallest motors however, are equipped with 1-piece covers
that are not designed for easy or convenient removal. On the 2.5 hp and
41516 hp, this cover is a low-rise component that should not interfere with
service procedures. For this reason, the cover is normally designed not to be
removed except during a complete overhaul where the powerhead is
removed from the midsection.
In a few cases, remote or tiller control cables (and choke mechanisms, if
equipped) must be disconnected andlor removed from the case in order to
completely remove the lower cases. But, for most procedures, the multi-
piece lower cases can be supported out of the way (using a length of
mechanic's wire or a bent wire coat hanger) with the cables still attached to
the cover. You'll have to decide for yourself how much trouble it is worth to
remove the covers for various maintenance procedures, but obviously they
must be completely removed for major overhauls.
To separate the lower covers on multi-piece models, proceed as follows:
1. On most models the top cover seal is mounted in the groove on the
-12 MAINTENANCE AND TUNE-UP
top cover, though for a few it may instead be placed on the top sealing
surface of the lower covers. On models where the seal is attached to the
lower covers, carefully lift it from the covers and place it aside where it will
not be damaged.
2. Locate and remove the cover retaining screws as follows:
a. On 2.5 hp motors, the lower cover is a low-rise, one-piece
component that should not interfere with service procedures. The cover is
normally not removed except during a complete overhaul where the
powerhead is removed from the gearcase.
b. On 41516 hp (1 38cc), the lower cover is a low-rise, one-piece
component that should not interfere with service procedures. The cover is
normally not removed except during a complete overhaul where the
powerhead is removed from the gearcase.
Fig. 47 Outboards are protected by a top
and either 1 or 2 (or more) lower engine Fig. 48 Most Suzuki top covers use either
covers an over-center latch like this. . .
Fig. 51 When removing the top cover on
Fig. 50 . . .which are simply rotated manual start models, carefully feed the
downward to open handle through the cover grommet
c. On 2002 or earlier 9.9115 hp motors, there is a port and starboard
cover half. Because the top cover seal is mounted on the lower cover halves,
start by carefully removing the rubber seal. Loosen the screw securing the
shiner lever to the front side of the case, then remove the lever. Next,
remove the two screws threaded downward at the front corners of the lower
covers. At the front latch (at the seam), remove the snap pin, washer, pin
and fastener for the latch, then remove the screw underneath the latch.
Moving to the starboard side of the cover, remove the 4 remaining cover
screws threaded from the starboard side. One at the lower rear (accessed
through a hole in the cover), one at the lower front, one at the upper front,
where the cover turns about 90Â from vertical to horizontal and finally one at
the top rear (inside the cover, also usually accessed through a hole).
Carefully remove the starboard side cover, then remove the port side cover,
Fig. 49 .. . or they use a number of latches
like this. . .
I
Fig. 52 The 2.5-6 hp motors use a 1-piece,
low-profile cover that rarely interferes with
service
Fig. 53 Multi-piece engine covers are
secured with screws. . . Fig. 55 . ..and at the rear of the outboard
d. On 2003-04 9,9115 hp motors, there is a port and starboard cover
half. Because the top cover seal is mounted on the lower cover halves, start
by carefully removing the rubber seal. Now, at the latch, remove the snap
pin, washer, pin and fastener for the latch, then remove the screw
underneath the latch. Moving to the starboard side of the cover, remove the
3 screwed threaded from that side. One at the lower rear (accessed through
a hole in the cover), one at the lower front and one at the upper front, where
the cover turns about 90Â from vertical to horizontal. At this point, remove the
bolt from the shifter lever and disconnect the lever (at the front corner of the
cover). Next, remove the two screws threaded downward at the front corners
of the lower covers. Disconnect the water hose, and carefully remove the
starboard side cover, then remove the port side cover.
e. On 2005 or later 9.9115 hp motors, there is a port and starboard
cover half. Because the top cover seal is mounted on the lower cover halves,
start by carefully removing the rubber seal. Next, remove the two screws
threaded downward at the front corners of the lower covers. Now, at the front
latch, remove the snap pin, washer, pin and fastener for the latch, then
remove the screw underneath the latch. Moving the starboard side of the
cover, remove the 3 screwed threaded from that side. One at the lower rear
(accessed through a hole in the cover), one at the lower front and one at the
upper front, where the cover turns about 90' from vertical to horizontal.
Disconnect the water hose, and carefully remove the starboard side cover,
then remove the port side cover.
f. On 25 hp V2, motors, there is a port and starboard cover half. Most,
but not all, of the boltslscrews for this cover should be threaded from the
outside of the covers. There are 5 located on the starboard side (3 at front,
one of which is on the inside, and two at rear of the cover) and 2 on the port
side of the cover (both at the front). To separate the covers start by pulling
out the rear hook, then removing the screws from the starboard cover and
pulling the cover far enough back to disconnect the cooling stream indicator
hose. With the starboard cover removed, all you need to do to remove the
port side cover is to loosen the 2 remaining screws and carefully pull it free.
g. On 25/30 hp 3-cylinder motors, there is a port and starboard cover
half. The bolts/screws for this cover should all the threaded from the outside
of the covers. There are 4 located on the port side (two at front and two at
rear of the cover), and 2 on the starboard side of the cover (both at the
front). Remove the fasteners, then carefully separate the covers.
h. On 40150 hp motors, there is a port and starboard cover half.
Because the top cover seal is mounted on the lower cover halves, start by
carefully removing the rubber seal. At the latch, remove the snap pin,
washer, pin and fastener securing the latch. Next, remove the five screws
along the outer perimeter of the port side cover (3 toward the front and 2
along the rear of the cover). Pull the port side cover far enough away from
the powerhead to disconnect the PTT switch lead, then remove the port side
cover comoletelv. Move to the other side of the outboard and remove the 3
screws (all toward the front of the cover perimeter), and remove the
starboard side cover.
i On 60170 hp motors, there is a port and starboard cover half.
Because the top cover seal is mounted on the lower cover halves, start by
carefully removing the rubber seal. At the latch, remove the snap pin,
washer, pin and fastener securing the latch. Next, remove the 4 bolts along
the outer perimeter of the starboard side cover (2 toward the front and 2
toward the rear of the cover). Pull the starboard side cover away from the
powerhead and remove it from the outboard. Move to the other side of the
outboard and remove the 2 screws/bolts (both toward the front of the cover
perimeter), then carefully pull the port side cover far enough away from the
powerhead to disconnect the PTT switch lead, and remove the port side
cover completely.
j. On 90111 5 hp and 140 hp motors, there is a port and starboard cover
half. Because the too cover seal is mounted on the lower cover halves. start
by carefully removing the rubber seal. Next, remove the 7 screws along the
outer perimeter of the starboard side cover (4 toward the front and 3 along
the rear of the cover) and the 2 screws from the port side cover (both toward
the front of the cover). Pull the port side cover far enough away from the
powerhead to disconnect the PTT switch lead, then remove the port and
starboard side covers completely.
k. On 150/1 75 hp motors, there are port and starboard covers, as well
as port and starboard oil pan covers. Start by removing the 6 screws (4
toward the front and 2 toward the back, including one inside the top of the
cover at both the front and back) which secure the starboard cover, then
remove the cover. Next remove the 2 screws from the port side cover (both
toward the front of the cover) and pull the port side cover far enough away
from the powerhead to disconnect the PTT switch lead, then remove the port
cover completely. If the port and starboard oil pan covers must be removed
as well, loosen the 5 screws (all located on the starboard side, 2 along the
rear of the cover and 3 along the front) and separate the pan covers from the
outboard.
I.On 20012251250 hp motors, there are port and starboard covers, as
well as port and starboard oil pan covers. Start by removing the 5 screws (3
toward the front and 2 toward the back) which secure the starboard cover,
then remove the cover. Next remove the 3 screws from the port side cover
(all toward the front of the cover) and pull the port side cover far enough
away from the powerhead to disconnect the PTT switch lead, then remove
the port cover completely. If the port and starboard oil pan covers must be
removed as well, loosen the 8 screws (some are located on either side) and
separate the pan covers from the outboard.
m. On 300 hp motors, there are port and starboard covers, as well as
port and starboard oil pan covers. Because the top cover seal is mounted on
the lower cover halves, start by carefully removing the rubber seal. Next,
remove the 6 screws (4 toward the front and 2 toward the back, including
one inside the top of the cover at both the front and back) which secure the
starboard cover, then remove the cover. Next remove the 4 screws from the
port side cover (all toward the front of the cover) and pull the port side cover
far enough away from the powerhead to disconnect the PTT switch lead,
Fig. 56 Exploded view of a typical 2-piece lower cover assembly
14 MAINTENANC
then remove the port cover completely. If the port and starboard oil pan
covers must be removed as well, loosen the 8 screws (all of which are
threaded from the starboard side, 3 along the rear of the cover and 5 along
the front) and separate the pan covers from the outboard.
Be careful to make sure that all fasteners are removed before trying to
separate the covers. Absolutely never force them. If it appears that they
are stuck, go back and recheck for any fasteners or screws that were
missed.
3. Once the screws are removed, pull the covers back for access.
Some covers will come off ~o~~ip~'eiei'~
a: this time, but others will still be
attached to the engine due to wires, cables or hoses that are also attached
to the cover. Either support the cover halves aside with these component still
attached, or free any remaining components from the cover halves and
remove thorn frnm the engine.
On many motors, especially the larger models, the covers mount to
one or more interference fit rubber mounts. It may take a gentle tug to
free the cover from these mounts.
4. Installation is the reverse of the removal procedure, making sure to
reattach any components that were freed from the cover or removed for
access. Be careful not to pinch or damage and hoses, cables or wiring when
seating the lower covers.
5. Tighten the cover screws securely, but do not over-tighten and crack
the covers or strip the screw threads.
6. Make sure the top cover seal is in proper position before installing
the top cover and securing the latch(es). The top cover must be a tight fit to
protect the motor from excessive spraylmoisture and to ensure the top cover
remains properly seated in use.
Fig. 58 A water source must be used
ANYTIME the engine is started
FLUSHING THE COOLING SYSTEM
SY
See Figures 58 thru 65
The most important service that you can perform on your motor's cooling
system is to flush it periodically using fresh, clean water. This should be
done immediately following any use in salt, brackish or polluted waters in
order to prevent mineral deposits or corrosion from clogging cooling
passages. Even if you do not always boat in salt or polluted waters, get used
to the flushing procedure and perform it often to ensure no silt or debris
clogs your cooling system over time.
E Flush the cooling system after any use in which the motor was
operated through suspendedlchurned-up silt, debris or sand.
Although the flushing procedure should take place right away (dockside or
on the trailer), be sure to protect the motor from damage due to possible
thermal shock. If the engine has just been run under high load or at
continued high speeds, allow time for it to cool to the point where the
powerhead can be touched. Do not pump very cold water through a very hot
engine, or you are just asking for trouble. If you trailer your boat short
distances, the flushing procedure can probably wait until you arrive home or
wherever the boat is stored, but ideally it should occur within an hour of use
in salt water. Remember that the corrosion process begins as soon as the
motor is removed from the water and exposed to air.
The flushing procedure is not used only for cooling system maintenance,
but it can also be a tool with which a technician can provide a source of
cooling water to protect the engine (and water pump impeller) from damage
anytime the motor needs to be run out of the water. Never start or run the
Fig. 60 Any model with water intakes on the
side of the gearcase, can be flushed or run
using a muff (clamp) type adaptor
Fig, 61 Most 9.9-50 hp models are equipped
with a gearcase flushing port (9.9115 hp Fig. 62 . . .the port requires the use of an Fig. 63 Flushing port location on a 40150 hp
shown). . . adapter (25130 hp 3-cyl shown) motor
-
engine out of the water, even for a few seconds, for any reason. Water pump
impeller damage can occur almost instantly and damage to the engine from
overheating can follow shortly thereafter. If the engine must be run out of the
water for tuning or testing, always connect an appropriate flushing device
before the engine is started and leave it turned on until after the engine is
shut off.
ANYTIME the engine is run, the first thing you should do is check the
cooling stream or water indicator. All of these models are equipped
with some form of a cooling stream indicator towards the aft portion of
the lower engine cover. Anytime the engine is operating, a steady
stream of water should come from the indicator, showing that the pump
is supplying water to the engine for cooling. If the stream is ever
absent, stop the motor and determine the cause before restarting.
As we stated earlier, flushing the cooling system consists of supplying
fresh, clean water to the system in order to clean deposits from the internal
passages. If the engine is running, the water does not normally have to be
pressurized, as it is delivered through the normal water intake passages and
the water pump (the system can self flush if supplied with clean water).
Smaller, portable engines can be flushed by mounted them in a test tank (a
sturdy, metallic 30 gallon drum or garbage pail tilled with clean water).
Most Suzuki engines will also accept flush fittings or adapters. Most
adapters are of the generic type and are designed to fit over the engine
water intakes on the gearcase (and resemble a pair of strange earmuffs with
a hose fitting on one side). When used, all motors can be run using this style
of adaptor.
The water intake point on a few of the smallestmotors, such as the
41516 hp, do not allow the use of "muff" type adapters. On the 41516 hp
motors the water intake point is directly under the anti-cavitation plate
instead of on the sides of the gearcase housing.
Other adapters (available from the manufacturer) are designed for special
flushing fittings on specific motors. These special adapters attach to a
cooling passage on the gearcase, powerhead or exhaust housing. When
using the later type adapter, follow the manufacturer's instructions closely
regarding flushing conditions. In some cases (as in with some of the motors),
flushing with this type of adapter should occur only with the motor turned off,
so as to prevent damage to the water pump impeller or other engine
components. This varies with each motor, so be sure to check with your
dealer regarding these direct to the powerhead adapters when you purchase
one.
Check the model on which you are working to see if there are any special
flush fittings or procedures as follows:
2.5 hp motors -use a water intake grates that are on either side of the
gearcase so they MAY accept a suitably sized earmuff style generic adapter
or there may be a specific adapter available from Suzuki. Regardless the tiny
size of this motor make is generally easiest to flush or run in a test tank or
pail.
* 41516 hp motors -use a water intake that is right above the propeller
and are generally flushed in a test tank or pail. In addition, they are normally
equipped with a flushing port on the underside of the powerhead. It is a
large, flat-head screw located right next to one of the powerhead mounting
bolts). A flush fitting which can attach to a garden hose should be threaded
into the hole after the screw is removed. ALSO, duct-tape should be used to
cover the water intake hole Oust above the propeller on the underside of the
anti-cavitation plate) to ensure proper pressure. These motors are normally
flushed with the engine running HOWEVER, DO NOT run them higher than
idle. Their small size also makes them ideal to be flushed in a test tank or
pail (that can be much easier).
9.9115 hp motors -normally have a flushing port on the starboard side
of gearcase, toward the top, rear side of the gearcase, just a little below the
split line. Aflush fitting which can attach to a garden hose should be
threaded into the hole after the screw plugging it is removed. ALSO, duct-
tape should be used to cover the water intake hole (just above the propeller
on the underside of the anti-cavitation plate) to ensure proper pressure.
These motors are normally flushed with the engine running HOWEVER, DO
NOT run them higher than idle. These motors are generally still small
enough to flush in a test tank or sturdy pail.
* 25 hp V2 motors -are not normally equipped with a flushing port.
Unless one is identified in your owner's manual, you will need to use muff
type adaptors over the water intakes on the side of the gearcase.
* 25130 hp (3-cyl) and 40150 hp motors -are equipped with a flushing
port on the starboard side of gearcase, toward the top, middle side of the
gearcase, just a little above the anti-cavitation plate and a little behind the
gearcase oil level plug. Aflush fitting which can attach to a garden hose can
be threaded into the hole after the screw plugging it is removed HOWEVER
this fitting SHOULD NOT BE USED to flush the powerhead with the motor
running. IF you need to flush the powerhead while running (or provide a
source of cooling water out of a test tank), then you will need to use muff
type adaptors over the water intakes on the side of the gearcase. As with
many some other Suzuki models, you must use duct-tape to cover the water
intake hole (just above the propeller on the underside of the anti-cavitation
plate) in order to ensure proper pressure.
60170 hp and 9011151140 hp motors -are equipped with a flushing port
on the lower port side of the exhaust housing, toward the rear of the housing,
usually JUST above the lower engine cover split line. Once the plug is
removed from the port you can either directly install a suitable garden hose
or use an adaptor to connect the hose to the thread in the motor. Even if the
thread is the same on the motor as the garden hose, a short adaptor can
make this job much easier. On most motors the thread should be 0.75 -11.5
NHR (ANSI) and readily available. HOWEVER this port is only for flushing
the motor with it NOT running. In order to flush these outboards with the
motor running, or provide a suitable source of cooling water away from a test
tank you will need to use standard muff type adaptors over the gearcase
water intake.
* 1501175 hp motors -are equipped with a flushing port, either on the
lower port side or rear of the exhaust housing. Once the plug is removed
from the port you can either directly install a suitable garden hose or use an
Fig. 64 Most 60 hp and larger outboards are equipped with a flush
port somewhere on the exhaust housing (70 hp motor shown) Fig. 65 Flushing port location on a 140 hp motor
adaptor to connect the hose to the thread in the motor. Even if the thread is
the same on the motor as the garden hose, a short adaptor can make this
job much easier. On most motors the thread should be 0.75 -11.5 NHR
(ANSI) and readily available. HOWEVER this port is only for flushing the
motor with it NOT running. In order to flush these outboards with the motor
running, or provide a suitable source of cooling water away from a test tank
you will need to use standard muff type adaptors over the gearcase water
intake.
20012251250 hp and 300 hp V6 motors -are equipped with a flush plug
at the rear center of the lower engine cowling. Once the plug is removed
from the port you can either directly install a suitable garden hose or use an
adaptor to connect the hose to the thread in the motor. Even if the thread is
the same on the motor as the garden hose, a short adaptor can make this
job much easier. The thread should be 0.75 -11.5 NHR (ANSI) and readily
available. HOWEVER this port is only for flushing the motor with it NOT
running. In order to flush these outboards with the motor running, or provide
a suitable source of cooling water away from a test tank you will need to use
standard muff type adaptors over the gearcase water intake.
When running the engine on a flushing adapter using a garden
hose, make sure the hose delivers 20-40 psi (140-300 kPa) of pressure.
Some of the smaller, portable motors covered by this manual utilize a
water intake that is directly above the propeller. On these models the
propeller must usually be removed before a clamp style flush adapter can be
connected to the motor (unless the adapter is very thin and mounted so
close to the anti-ventilation plate that it will not be hit by the propeller).
For safety, the propeller should be removed ANYTIME the motor is run
on the trailer or on an engine stand. We realize that this is not always
practical when flushing the engine on the trailer, but cannot emphasize
enough how much caution must be exercised to prevent injury to you
or someone else. Either take the time to remove the propeller or take
the time to make sure no-one or nothing comes close enough to it to
become injured. Serious personal injury or death could result from
contact with the spinning propeller.
When using a flushing device and a pressurized water source, most
motors can be flushed tilted or in a vertical position, BUT, the manufacturer
warns against flushing most motors in the tilted position with the engine
running. Many 4-strokes can be seriously damaged by attempting to flush
them with the engine running in the full tilt position. If the motor must be
flushed tilted (dockside) then your best bet is to do so with the engine shut
off.
1. Check the engine top case and, if necessary remove it to check the
powerhead, to ensure it is cooled enough to flush without causing thermal
shock.
2. Prepare the engine for flushing depending on the method you are
using as follows:
a. If using a test tank, make sure the tank is made of sturdy material,
then securely mount the motor to the tank. If necessary, position a wooden
plank between the tank and engine clamp bracket for thickness. Fill the tank
so the water level is at least 4 in. (10cm) above the anti-ventilation plate
(above the water inlet).
b. If using a flushing adapter of either the generic clamp-type or specific
port-type for your model attach the water hose to the flush test adapter and
connect the adapter to the motor following the instructions that came with the
adapter. If the motor is to be run (for flushing or testing), position the
outboard vertically and remove the propeller, for safety. Also, be sure to
position the water hose so it will not contact with moving parts (tie the hose
out of the way with mechanic's wire or wire ties, as necessary).
Check the list earlier in this section for the model on which you are
working. Many of the flush ports CANNOT be used with the engine
runnina.
When using a clamp-type adapter, position i.ic-W.AJ ,ip(s) over
water intake grate(s) in such a way that they form tight seals. A little
pressure seepage should not be a problem, but look to the water
stream indicator once the motor is running to be sure that sufficient
water is reaching the powerhead.
3. If !lsi!lg a damp-type flush test adapter, follow any special
iiistruciions foi YOLK model, as noted earlier.
4. Unless using a lest tank, turn the water on, making sure that
pressure does not exceed 40 psi (300 IkPa).
5. It !.!sin:i a lest tank or if the motor must be run for testingltuning
procedures, 5kii the engine and run in neutral until the motor reaches
operating temperature. For most motors, the motor will continue to run at fast
idle until warmed, on fuel injected motors, speed will be automatically
nsgulaied by the Engine Control Unit (ECU).
As soon as the engine starts, check the cooling system indicator
m.it must be present and strong as long as the motor is operated.
stop the motor and rectify the problem before proceeding.
Common problems could include insufficient water pressure or
6,Flush the motor for about 5-10 minutes or untii the water exiting the
engine is clear. When flushing while running the motor, check the engine
temperature (using a gauge or carefully by touch) and stop the engine
immediately if steam or overheating starts to occur. Make sure that
carbureted motors slow to low idle for the last few minutes of the flushing
procedure.
7. Stop the engine (if running), then shut the water off.
8. Remove the adapter from the engine or the engine from the test
tank, as applicable.
9. If flushing did not occur with the motor running (so the motor would
already by vertical), be sure to place it in the full vertical position allowing the
cooling system to drain. This is especially important if the engine is going to
be placed into storage and could be exposed to freezing temperatures.
Water left in the motor could freeze and crack the powerhead or gearcase.
OIL RECOMMENDATIONS
For all motors covered here Suzuki recommends the use of Suzuki brand
4-Stroke 10W-40 oil or an equivalent. When this oil is used, the oil can be
changed after every 200 hours of operation (or at the end of each season.
whichever comes first). If this oil is not available, Suzuki advises that a high
quality oil of the correct viscosity can be substituted. For all motors this
means using an SAE 10W-40 API SE, SF, SG, SH or SJ (or latest
superseding oil type) or NMMA (National Marine Manufacturer's Association)
FCW 10W-40 motor oil.
The Society of Automotive Engineers (SAE) grade number indicates the
viscosity of the engine oil; its resistance to flow at a given temperature. The
lower the SAE grade number, the lighter the oil. For example, the mono-
grade oils begin with SAE 5 weight, which is a thin light oil, and continue in
viscosity up to SAE 80 or 90 weight, which are heavy gear lubricants. These
oils are also known as "straight weight", meaning they are of a single
viscosity, and do not vary with engine temperature.
Multi-viscosity oils offer the important advantage of being adaptable to
temperature extremes. These oils have designations such as 10W-40, 20W-
50, etc. The 10W-40 means that in winter (the "W in the designation) the oil
acts like a thin 10 weight oil, allowing the engine to spin easily when cold
and offering rapid lubrication. Once the engine has warmed up, however, the
oil acts like a straight 40 weight, maintaining good lubrication and protection
for the engine's internal components. A 20W-50 oil would therefore be
slightly heavier than and not as ideal in cold weather as the 10W-40, but
would offer better protection at higher rpm and temperatures because when
warm it acts like a 50 weight oil. Whichever oil viscosity you choose when
changing the oil, make sure you are anticipating the temperatures your
engine will be operating in until the oil is changed again.
The American Petroleum Institute (API) designation indicates the
classification of engine oil used under certain given operating conditions.
Only oils designated for use "Service SG, SH, SJ" or greater should be used.
Oils of the SG, SH, SJ or its superseding oil type perform a variety of
functions inside the engine in addition to the basic function as a lubricant.
Through a balanced system of metallic detergents and polymeric
dispersmt:, ...,w c:.! pievents the formation of high and low temperature
deposits and also keeps sludge and particles of dirt in suspension. Acids,
particularly sulfuric acid, as well as other by-products of combustion, hie
neutralized. Both the SAE grade number and the API designation can be
found on top of the oil can.
Although 10W-40 (or 10W-50) is the preferred oil weight for these
motors for all ambient temperatures, the following weights may be
substituted depending on the lowest or highest anticipated ambient
temperature. 10W-30 can be used for temps from -4OF (-20%) to 86'F
(30¡C) but not any higher a temp. Similarly, 15W-40 or 15W-50 can be
used at any ambient temps of 3'F (-15%) or higher. Also, 20W-50 can
be used at any ambient temps of 14'F (-10%) or higher.
CHECKING OIL LEVEL
-
See Figures 66 thru 76
One of the most important service items for a 4-stroke engine is
maintaining the proper level of fresh, clean engine oil in the crankcase. Be
certain to check the oil level both before and after each time the boat is
used. In order to check the oil level the motor must be placed in the full
vertical position. Because it takes some time for the oil to settle (and at least
partially cool), the engine must be shut off for at least 30 minutes before an
accurate reading can be attained. If the boat is trailered, use the time for
loading the boat onto the trailer and prepping the trailer for towing to allow
the motor to cool. If the boat is kept in the water, take some time around the
dock to secure lines, stow away items kept onboard and clean up the deck
while waiting for the oil to settlelcool.
Running an engine with an improper oil level can cause significant
engine damage. Although it is typically worse to run an engine with
abnormally low oil, it can be just as harmful to run an engine that is
overfilled. Don't take that risk, make checking the engine oil a regular
part of your launch and recoveryldocking routine.
Most motors covered by this manual are equipped with an automotive-
style dipstick and oil filler cap located on the powerhead. The engine cover
must be removed for access, but once removed it should be easy to locate
the dipstick and filler cap if you look in the right spot (as they vary with the
engine size):
* On 2.5 hp motors (like the 41516 hp models) are unique in that they
have a sight glass on the port side of the powerhead, visible through the
lower engine cowling. There is a small circle, within the circle of the sight
glass and the oil should always AT LEAST be up to the bottom of that inner
circle (that's the lower limit), or when properly filled it should be just up to the
too of that inner circle. Under the too enaine cover, on the same side and
just a little forward of the sight glass is & oil filler cap threaded into the side
of the powerhead.
* On 41516 hp motors there is a sight glass on the port side of the
powerhead, visible through the lower engine cowling. This glass is the quick
way to check oil level at just a glance. The oil should be up to the top of the
glass (that's the lower limit). In addition, a little forward of the site glass is a
filler cap that is screwed into the crankcase. The filler cap contains a dipstick
with upper and lower fill limit markings on it. When checking the oil level with
this dipstick DO NOT rethread it into the crankcase, just insert it, sitting on
the end of the threads, then remove it again and check the level.
* On 9.9115 motors, the oil dipstick location varies slightly by year. For
models through 2002 the dipstick is on the top, rear, starboard side of the
motor just a little in front of the oil filler cap (there is a photo of it included
here). However, on 2003 or later models it is on the port side of the
powerhead, just outboard of the ignition coil (a little more than halfway
toward the back of the motor). For all years, the oil filler cap is on the aft,
starboard side, near the top of the powerhead, behind the hand rewind
starter cover. The color and shape of the dipsticks and oil caps varied
through the years on these models.
* On 25 hp V2 motors, the combination oil dipstick/filler cap is on the
port side of the powerhead, about halfway back from the front of the
powerhead (right behind the ignition modulelCD! unit and just in front of the
engine lifting bracket.
Fig. 67 .. .they also have a filler cap (with a Fig. 68 Most dipsticks are found on the port
Fig. 66 The 2.5-6 hp motors have a sight built-in dipstick on 41516 hp models) on that side of the motor and though this one from
glass on the port side. . . side too a 15 hp motors is black. . .
Fig. 70 Some are partially shrouded by the Fig. 71 Of course there are exceptions, like
Fig. 69 ...most are colored yellow (such as lower engine cover (such as this from a this early-model 9.9 hp motors with the
this from a 60R0 hp motor) 40150 hp motor) dipstick toward the starboard side
1 Fig. 72 Although the markings vary,
dipsticks will contain a full and a low or add Fig. 73 The oil fill cap is sometimes found Fig. 74 . . . or midway up the cover (6010
mark on top of the rocker cover (40150 hp). .. hp)
Fig. 75 Other times the fill cap is simply on top of the motor (140
hp shown)
* On 25130 hp 3-cyl motors, the oil dipstick is on the port side of the
powerhead, about halfway back from the front of the powerhead (a bit behind
the electric starter, if equipped, and a bit in front of the 3 ignition coils). The
oil filler cap is on the opposite (starboard) side, at the top of the powerhead,
toward the rear of the powerhead.
On 40150 hp motors, the oil dipstick is on the lower port side of the
powerhead (toward the rear of the intake manifold), while the oil filler cap is
found on top of the rocker arm cover (at the top rear of the motor.)
On 60170 hp motors, the oil dipstick is on the lower rearlport side of the
powerhead (toward the rear of the intake manifold), while the oil filler cap is
found toward the bottom of the rocker arm cover (at the rear of the motor.)
On 90/115/140 hp motors, the oil dipstick is on the lower mid-port side
of the powerhead (at the base of the powerhead, below and a tad behind the
electric starter), while the oil filler cap is found on top of the rocker arm cover
(at the top rear of the motor.)
a On I501175 hp motors, the oil dipstick is on the lower mid-starboard
side of the powerhead (just in front of the oil filter about centered under the
intake manifold) at the base of the powerhead, while the oil filler cap is found
at the top rear of the powerhead, just behind the flywheel cover.
On 20012251250 hp motors, the oil dipstick is on the lower mid-
starboard side of the powerhead (at the base of the powerhead, below and
behind the electric starter and the oil filter), while the oil filler cap is found at
the top, opposite side of the powerhead, at the top of the port side cylinder
banklvalve cover.
On 300 hp rnoiors, ihe oil dipstick is on the lower mid-starboard side of
the powerhead (at the base of the powerhead, about halfway back), while
Fig. 76 Regardless, it is usually labeled clearly or is pretty obvious
(9.9115 hp shown)
the oil filler cap is found at the top, opposite side of the powerhead, at the
top of the port side cylinder bank of the powerhead.
1. Make sure the engine is in the full vertical position and has been shut
off for at least 30 minutes. If possible, get in the habit of checking the oil with
the engine cold from sitting overnight.
2. On 2.5 hp motors there is no need to even remove the engine cover
(unless you find a need to top off the motor) simply peer through the sight
glass and make sure the oil is somewhere inside the smaller circle inside the
sight glass. The bottom of that inner circle is the lower limit and the top is the
upper.
3. Remove the engine cover.
4. On 41516 hp motors you've got a choice, you can simply use the sight
glass (the upper end of the glass is the LOWER limit for the oil level, so if
you see air instead of oil, it is low) OR you can use the dipstick attached to
the filler cap. Remember when using the dipstick on this motor that you
SHOULD NOT rethread it when reading the level, but instead sit the stick
carefully on the end of the threads. Otherwise instructions are the same as
follows for using a dipstick.
5. Carefully pull the engine crankcase oil dipstick from the side of the
engine (port for all except the 150 hp and larger motors or the 9.9115 hp
motors through 2002 which are starboard).
6. Wipe all traces of oil off the dipstick using a clean, lint free rag or
cloth, then re-insert dipstick back into its opening until it is fully seated. Then,
pull the dipstick out from the crankcase again and hold it vertically with the
bottom end facing down in order to prevent a false oil reading.
Forget how your dad or buddy first taught you to read the level on a
dipstick. It may be more convenient to hold it horizontally, but laying it
down like that could allow oil to flow UPWARD giving a false high, or
worse, false acceptable reading when in fact your engine needs oil.
Last time we checked, oil won't flow UP a dipstick held vertically (but
the high point of the oil will remain wet in contrast to the dry portion of
the stick immediately above the wet line). So hold the dipstick vertically
and you'll never run your engine with insufficient oil when you thought
it was full.
7. If the oil level is at or slightly below the top or FULL mark on the
dipstick, the oil level is fine. If not. add small amounts of oil through the filler
cap until the level is correct. Add oil slowly, giving it time to settle into the
crankcase before rechecking and again, don't overfill it either.
Dipstick markings will vary slightly from model-to-model. Some are
equipped with an "L" (low) and "F" (full), while some other dipsticks
spell out the words "low" and "full"; and still others like the 25 hp V2
models simply have a full level LINE and a low level LINE. Many of the
mid-range-to-larger motors are equipped with add and full marks that
contain a crosshatched area between them. The crosshatched area is
the "acceptable" operating range, but try to maintain the level towards
the top of the markings. And some of the larger motors may use a
dipstick that contains just two dots, the bottom one for add and the top
for full.
8. Visually check the oil on the dipstick for water (a milky appearance
will result from contamination with moisture) or a significant fuel odor. Both
can be signs that the powerhead likely needs overhaul to prevent damage,
Fig. 77 Oil drain plug on 41516 hp (138cc) motors
though a milky oil can also be a sign of a motor that has not had the oil
changed and been exposed to FAR too many heating and cooling cycles
without full warming causing condensation.
9. Insert and properly seat the oil dipstick into the powerhead when you
are finished. If removed, install the oil fill cap and rotate it until it gently locks
into position.
OIL CHANGE & FILTER SERVICE
@ See Figures 77 thru 83
2001 and later EFI motors are equipped with an oil change reminder
system which will activate the buzzer and, on remote control models,
the oil lamp to indicate sufficient operating hours have passed to
require an oil change. For more details on this system please refer to
Oil Change Reminder System in the EFI section.
Next to regular fluid level checks, the most important way to maintain a 4-
stroke outboard motor is to change the engine crankcase oil (and change or
clean the filter, as applicable) on a regular basis. Generally Suzuki
recommends this service be performed every 200 hours or at the end of
each season, immediately before the motor is placed into storage. That is, as
long as you use an equivalent high-quality, high-detergent oil of the proper
viscosity (SAE 10W-40) For more information regarding engine oil, refer to
OIL RECOMMENDATIONS earlier in this section.
Research from experts who deal with these motors every day tells us
that some of the early mid-range and larger hp models were especially
subject to camshaft lobe wear if the engine oil was not changed
regularly. During each pre-season tune-up, watch for excessive
changes in valve clearance as possible signs of wear. If found, change
the oil more freauentlv or. if oil other than the manufacturer's
recommended brand is being used, try changing the type of oil too.
Whenever the engine oil is drained, the oil filter should also be serviced.
Most of the models covered by this manual utilize one of two categories of oil
filters, the first being reusable elements and the second being disposable
elements. We say MOST, because the smallest motor, 2.5 hp, does not use
a filter.
The 41516 hp motors utilize a reusable element which is nothing more than
a filter screen mounted in a holder on the bottom of the crankcase, under the
oil pump assembly.
All 9.9 hp and larger motors are equipped with a disposable element. For
the 9.9115 hp motors this is a cylindrical paper element with metal or
composite end-caps that is installed in a bore in the crankcase and sealed
with a cover and O-rings. The rest of the motors (25 hp and larger), utilize a
disposable, automotive style, spin-on filter mounted to the side of the
powerhead. The best method to remove the spin-on filter (resulting in fewest
skinned knuckles) is a filter wrench, and our preference is the cap style that
fits over the end of the filter (but a compressing band clamp style can work
well too if it's the right size). When purchasing a replacement oil filter check
Fig. 80 . ..but on 9.9115 hp, 25/30 hp (3-cyl)
Fig. 78 The oil drain plug is usually located Fig. 79 For 25 hp V2,40-70 hp and 200-300 hp and 90-140 hp motors, the plug is on the
near the bottom of the engine cover motors the drain plug is on the port side. .. starboard side
Fig. 82 All 25-300 hp motors use a Fig. 83 The oil filter on most of the EFI
Fig. 81 On 9.9115 hp motors the filter is disposable spin-on oil filter which is OFTEN motors is mounted directly under the intake
mounted under a bolted cap assembly hidden behind an engine cover manifold
your local marine dealer or automotive parts dealer for a cap or band wrench
that fits the filter.
Most people who have worked on their own machines, whether that is
tractors, motorcycles, carsltrucks or boat motors, will tell you that oil should
be changed hot. This seems to have always been the popular method, and it
works well since hot oil flows betterlfaster and may remove more deposits
that are still held in suspension. Of course, hot oil can be messy or even a
little bit dangerous to work with. Coupled with the sometimes difficult method
of draining oil from amoutboard, this might make it better in some instances
to drain the oil cold. Of course, if this is desired, you'll have to leave more
time for the oil to drain completely, thereby removing as much contaminants
as possible from the crankcase. The choice is really yours, but be sure to
take the appropriate steps to protect yourself either way.
@ If the engine is not being placed in storage after the oil change, it
should be run to normal operating temperature (in a test tank or with a
flushing device) and inspected for leaks before returning it to service. If
the engine is being placed into storage it should also be run using a
flush device, just start and run the engine for a few minutes to
thoroughly circulate the fresh oil, then prepare it for storage by fogging
the motor.
If you decide to change oil with the engine hot, a source of cooling such
as a test tank or flushing hose must be attached to the engine to prevent
impeller or powerhead damage when running the engine to normal operating
temperature. If you are lucky enough to store the boat (or live) close to
waters in which to use the boat, you can simply enjoy a morning, evening or
whole day on the water before changing the oil. The amount of time
necessary to haul the boat and tow it to your work area should allow the oil
to cool enough so that it won't be scalding hot, but still warm enough to flow
well.
@ Although it is not recommended for normal service, the oil CAN be
drained without removing the engine cases (on most models) or
servicing the filter. This might be desired if too much oil was added
during a routine level check or if a small sample of oil is to be removed
for inspection.
1. Prepare the engine and work area for the oil change by placing the
motor in a fullv vertical oosition over a larae, flattened cardboard box (which
can be used tb catch any dripping oil missed by the drain pan). Have a drain
pan, a few quarts larger than the capacity (refer to the Capacities -Four
Stroke Engines chart) for the motor and a lot of clean rags or disposable
shop towels handy.
A lower engine cover must be removed to service all oil filters
EXCEPT the 25 hp V2 and the 300 hp V6. For all other models you must
remove either the port or starboard cover for access, depending upon
where the filter is located. On 25-70 hp inline motors, as well as 200-250
hp V6 models this means you need to remove the PORT side engine
cover. On 90-175 hp inline models you need to remove the Starboard
engine cover. On 39/15 hp Suzuki mentions removing both covers,
probably because it's easier than just trying to remove the one, but you
can decide for yourself once you locate the cover for the filter. It really
just depends on the stability of the other cover, if the other cover is
secure, then removing just the one is probably fine. For details, refer to
the Engine Cover procedure in this section.
2. Remove the upper engine cover and locate the oil filter. Determine if
it is necessary to remove the lower side engine cover(s) based on access to
the filter. If necessary or desired, refer to the Engine Cover procedure for
more details.
M Before removing the powerhead on a 41516 hp (138cc) motor for
access to the oil filterlpump assembly, at least double-check under the
cowling to make sure no access panel has been added to the design.
a. On 41516 hp motors we've got bad news for you. The filter "element"
is a small screen that is secured in a holder underneath the crankcase. The
only way to access it is to Remove the Powerhead (yes, you read that
correctly, you need to remove the powerhead and separate the lower engine
cowlina. then remove the filter screen holder from the bottom of the
crankcase). It looks like the holder probably pulls straight out of the bottom of
the gearcase, but no details are given in the Suzuki service information to
confirm this. The filter screen can be washed in solvent, dried with
compressed air and then reinstalled. Although it is not critical which you do
first on these models, it is probably easier to drain the engine oil before
attempting to access the filter.
b. On 9.9115 hp motors, the disposable replacement element is housed
in bore on the port side of the crankcase block, right before the cylinder head
split line. Three bolts secure a rounded cover over the housing. A spring
which rests against the center of the cover holds the filter securely in the
bore when the cover is in place, while a small O-ring seals the inner end
(block end) of the filter and a large O-ring seals the cover. The lower engine
on that side really much be removed for access. When servicing the filter
ALWAYS use new O-rings and make sure remove both of the old O-rings
(don't leave that little one in the bore if it separates from the filter). Also,
during assembly, be sure the spring is seated between the filter and cover.
c. On 25 hp V2 motors, the disposable spin-on (automotive style) filter
is located on the STARBOARD side of the powerhead, right in front of the
powerhead lift bracket. There is no need to remove the lower engine covers
for access on this model.
d. On 25/30 hp (3-cyl), 40-70 hp and 200-250 hp motors, the
disposable spin-on (automotive style) filter is located on the PORT side of
the powerhead. For access you should remove at least the port side cover.
Service is fairly straight forward from that point.
e. On 90-175 hp motors, the disposable spin-on (automotive style) filter
is located on the STARBOARD side of ihe ~owerhead. For access YOU
should remove at least the starboard side cover. Service is fairly straight
forward from that point.
f. On 300 hp motors, the disposable spin-on (automotive style) filter is
located on the STARBOARD side of the powerhead, a little below and
behind the starter motors. There is no need to remove the lower engine
covers for access on this model.
The drain plug on MOST motors requires a suitably sized Allen
wrench.
3. Locate and remove the oil drain plug and gasket as follows:
a On 2.5 hp models a drain plug is located somewhere on the underside
of the powerheadllower engine cover assembly. It's close to the swivel
bracket, just a little outboard of a few of the powerheadlcover mounting bolts.
On 41516 hp models the drain plug (usually a large, flat-heat screw, but
we believe a 6mm Allen head bolt has been used on some models) is
located on the underside of the powerhead (a little behind the choke knob
and just far back ertough to put it in the vicinity of the sight glass).
On 9.9115 hp, 25/30 hp (3-cyi) and 90-140 hp motors, the plug is on
the starboard lower side of the outboard, towards the front of the motor, just
above or at the base of the lower cover split line.
On 25 hp V2,40-70 hp and 200-300 hp motors the plug is on the port,
lower side of the outboard, towards the front of the motor.
B In order to improve oil flow while draining, remove the oil fill cap.
4. Either hold the drain pan tightly against the side of the motor, or allow
the oil to run down the side of the motor and drip into the pan. The later
method is preferred if draining the engine cold as the oil will require more
time to drain than you will want to stand there with the pan in your hand.
In some cases you may be able to tilt the motor slightly and turn it
toward the drain pan in order to help the oil to drain out and downward
into the pan as opposed to out and all over the motor.
5. Inspect the drain plug and gasket for signs of damage. Replace the
plug or gasket if any damage is found. Also, watch the draining oil for signs
of contamination by moisture (a milky appearance will result), by fuel (a
strong odor and thinner running oil would be present) or signs of metallic
flakeslparticles. A small amount of tiny metallic particles is a sign of normal
wear, but large amounts or large pieces indicate internal engine damage and
the need for an overhaul to determine and rectify the cause.
6. When it appears that the oil has drained, tilt the engine slightly and
pivot it toward the drain plug side to ensure complete oil drainage. Clean the
drain plug, the engine and the gearcase. Place a new gasket onto the drain
plug then carefully thread the plug into the opening. Tighten the plug
securely. On models with Allen head drain plugs tighten the plug to 7 ft. Ibs.
(1 0 Nm) for 2.5-6 hp motors or to 9.5 ft. lbs.1115 inch Ibs. (1 3 Nm) for 9.9-
250 hp motors,
Although it is not absolutely necessary to replace the gasket each
time, it is a cheap way to help protect against possible leaks. We think
it is a good idea.
7. On 41516 hp models, service the filter screen as follows:
a. Remove the powerhead from the lower cover. For details, refer to the
Removal & Installation procedure in the Powerhead section.
b. Free the rounded filter holder from the underside of the crankcase,
right below the oil pump.
c. Inspect the screen for signs of contamination, clogging or damage,
then clean it with solvent or replace it, as applicable. Reinstall the filter, filter
holder and finally the powerhead.
8. For models equipped with a disposable, element mounted inside the
crankcaselblock (9.9115 hp motors) remove and service the filter as follows:
d, Make sure the lower engine cover($ were removed earlier.
e. Place a couple of stout shop rags under the oil filter housing, then
loosen and remove the 3 bolts securing the filter cover to the crankcase.
f. Slowly pull back on the top of the cover to break the seal, then pull
the cover off while keeping track of the spring.
g. Remove and discard the filter and the old O-rings (both the large
cover O-ring and the smaller filter O-ring which goes between the filter and
the inner portion of the filter chamber.
Although not specified by Suzuki, it is usually a good idea to coat
the new housing O-ring lightly with some fresh engine oil before
installation.
h. Position the NEW O-rings, followed by the filter. Make sure the filter
seats in the chamber, then position the spring and finally the cover. Install
the cover screws and tighten securely.
B Although the procedure for spin-on filters talks about placing a
shop rag under the filter while it is removed, there is an alternate
method to prevent a mess. If desired, loosen the filter slightly with a
cap wrench, then slide a disposable Zip-Lock(r) or similar food storage
bag completely over the filter and unthread it into the bag. Position the
shop rag anyway, just to be sure to catch any stray oil that escapes.
With a little practice, you'll find this method can be one of the best
ways to remove oil filters. Another method to help prevent a mess it to
pre-drain the filter before removal by making a couple of small holes in
it with a small punch (one toward the top for ventilation and one or
more on the bottom for draining).
9. For models equipped with a disposable, spin-on filter element (25-
300 hp motors) remove and service the filter as follows:
a. Except for 25 hp V2 and 300 hp V6 motors, make sure the lower
engine coverts) were removed earlier. We say except, but it is a lot easier to
position a small drain pan or rage if you also remove the cover on these
motors.
b. Position a small drain pain andlor a shop rag underneath the filter,
then place the oil filter wrench onto filter element.
c. Loosen the spin-on element by turning the filter wrench
counterclockwise, then remove the wrench and finish unthreading the
element by hand. Remove the filter from the powerhead and clean up any
spilled oil.
d. Make sure the rubber gasket is not stuck to the oil filter mounting
surface, then use a lint free shop rag to clean all dirt and oil from mounting
surface.
e. Apply a thin coating of engine oil to the sealing ring of the new oil
filter, then thread the filter onto the adapter until the sealing washer touches
the mounting surface. Tighten the filter using a cap wrench and a torque
wrench to 10 ft. Ibs. (14 Nm) and then tighten it an additional 314 turn.
10. Clean up any spilled oil, and then install the lower engine [email protected]) by
carefully aligning the screw holes in the two covers, while also aligning the
lower cover mating surfaces. Be sure to install and tighten the screws
securely. Also, don't forget to install any additional removed components
such as the aft cover latch andlor the cover seal.
11. Refill the engine through the oil filler cap as described under
Checking Engine Oil in this section. Add the oil gradually, checking the oil
level frequently. Add oil until the level reaches the upper dipstick or Full
mark.
12. Provide a temporary cooling system to the engine as detailed under
Flushing The Cooling System, then start the engine and run it to normal
operating temperature while visually checking for leakage.
If the engine is being placed into storage, don't run the motor too
long, just long enough to use a can of fogging spray. Between the fresh
oil circulated through the motor and the fogging spray coating the
inside of the intake and combustion chambers you motor should sleep
like a baby until next season.
13. Stop the motor and allow it to cool, then properly re-check the oil
level after it has settled again into the crankcase.
14. If removed for access, install the lower engine cover(s).
15. On 2001 or later EFI motors, if the system has been activated refer
to the Oil Change Reminder System in the EFI section to reset the oil
change reminder.
 See Figures 84 and 85
Regular maintenance and inspection of the lower unit is critical for proper
operation and reliability. A lower unit can quickly fail if it becomes heavily
contaminated with water or excessively low on oil. The most common cause
of a lower unit failure is water contamination.
Water in the lower unit is usually caused by fishing line or other foreign
material, becoming entangled around the propeller shaft and damaging the
seal. If the line is not removed, it will eventually cut the propeller shaft seal
and allow water to enter the lower unit. Fishing line has also been known to
cut a groove in the propeller shaft if left neglected over time. This area
should be checked frequently,
OIL RECOMMENDATIONS
Use Suzuki Outboard Motor Gear Oil, or an equivalent high quality, SAE
#90 gearcase hypoid lube. These oils are designed to ensure optimal
performance and to minimize corrosion in the lower unit.
Remember, it is this lower unit lubricant that prevents corrosion and
lubricates the internal parts of the drive gears. Lack of lubrication due
to water contamination or the improper type of oil can cause
catastrophic lower unit failure.
Fig. 84 This lower unit was destroyed Fia. 86 The ventllevel olua is alwavs near 1
because the bearing carrier froze due to Fig. 85 Fishing line entangled behind the the top, while the fill and drain plug is near
lack of lubrication prop can actually cut through the seal the bottom of the gearcase
I
CHECKING GEARCASE OIL LEVEL & CONDITION
+ See Figure 86
Visually inspect the gearcase before and after each use for signs of
leakage. At least monthly, or as needed, remove the gearcase level plug in
order to check the lubricant level and condition as follows:
1. Position the engine in the upright position with the motor shut off for
at least 1 hour. Whenever possible, checking the level overnight cold will
give a true indication of the level without having to account for heat
expansion.
2. Disconnect the negative battery cable or remove the propeller for
safety.
Always observe extreme care when working anywhere near the
propeller. Take steps to ensure that no accidental attempt to start the
engine occurs while work is being performed or remove the propeller
completely to be safe.
3. Position a small drain pan under the gearcase, then unthread the
drainlfiller plug at the bottom of the housing just enough to allow a small
smote (a teaspoon or less) to drain from the gearcase. Quickly install the
drainifiller plug and tighten securely.
4. Examine the gear oil as follows:
a. Visually check the oil for obvious signs of water. A small amount of
moisture may be present from condensation, especially if a motor has been
stored tor some time, but a milky appearance indicates that either the fluid
has not been changed in ages or the gearcase allowing some water to
intrude. If significant water contamination is present, the first suspect is the
propeller shaft seal.
b. Dip an otherwise clean finger into the oil, then rub a small amount of
the fluid between your finger and your thumb to check for the presence of
debris. The lubricant should feel smooth. A very small amount of metallic
shavings may be present, but should not really be felt. Large amounts of grit
or metallic particles indicate the need to overhaul the gearcase looking for
damaged/worn gears, shafts, bearings or thrust surfaces.
M If a large amount of lubricant escapes when the levellvent plug is
removed, either the gearcase was seriously overfilled on the last
service, the crankcase is still too hot from the last use (and the fluid is
expanded) or a large amount of water has entered the gearcase. If the
later is true, some water should escape before the oil and/or the oil will
be a milky white in appearance (showing the moisture contamination).
5. Next, remove the levellvent plug from the top of the gearcase and
ensure the lubricant level is up to the bottom of the levellvent plug opening.
A very small amount of fluid may be added through the level plug, but larger
amounts of fluid should be added through the drainlfiller plug opening to
make certain that the case is properly filled. If necessary, add gear oil until
fluid flows from the levellvent opening. If much more than 1 oz. (29 ml) is
required to fill the gearcase, check the case carefully for leaks. Install the
drainlfiller plugs and/or the levellvent plug, then tighten both securely.
M One trick that makes adding gearcase oil less messy is to install the
levellvent plug BEFORE removing the pump from the drainlfiller
opening and threading the drainlfiller plug back into position.
6. Once fluid is pumped into the gearcase, let the unit sit in a shaded
area for at least 1 hour for the fluid to settle. Recheck the fluid level and, if
necessary, add more lubricant.
7. Install the propeller andlor connect the negative battery cable, as
applicable.
DRAINING AND FILLING
See Figures 87,88 and 88a
The EPA warns that prolonged contact with used engine oil may cause
a number of skin disorders, including cancer! You should make every
effort to minimize your exposure to used engine oil. Protective gloves
should be worn when changing the oil. Wash your hands and any other
exposed skin areas as soon as possible after exposure to used engine
oil. Soao and water or waterless hand cleaner should be used.
1. Place a suitable container under the lower unit.
2. Loosen the oil levellvent plug on the lower unit. This step is
important! If the oil levellvent plug cannot be loosened or removed, you
cannot complete lower unit lubricant service.
B Don't remove the vent or filler plugs when the lower unit is hot.
Expanded lubricant will be released through the hole.
3. Remove the drainlfiller plug from the lower end of the gear housing
followed by the oil levellvent plug.
4. Allow the lubricant to completely drain from the lower unit.
5. If applicable, check the magnet end of the drain screw for metal
particles. Some amount of metal is considered normal wear is to be
expected but if there are signs of metal chips or excessive metal particles,
the gearcase needs to be disassembled and inspected.
6. Inspect the lubricant for the presence of a milky white substance,
water or metallic particles. If any of these conditions are present, the lower
unit should be serviced immediately.
7. Place the outboard in the proper position for filling the lower unit. The
lower unit should not list to either port or starboard and should be completely
vertical.
8. Insert the lubricant tube into the oil drain hole at the bottom of the
lower unit and inject lubricant until the excess begins to come out the oil
level hole.
W The lubricant must be filled from the bottom to prevent air from
being trapped in the lower unit. Air displaces lubricant and can cause a
tack of lubrication or a false lubricant level in the lower unit.
9. Oil should be squeezed in using a tube or with the larger quantities,
by using a pump kit to fill the gearcase through the drain plug.
Fig. 87 On most 50 hp and smaller Fig. 88 Gearcase oil is pumped into the Fig. 88a The best method of refilling a
gearcases, DO NOT confuse the FLUSH plug lower unit through the filler, while the vent is gearcase is to use some form of a hand
with the VENT plug used to let air escape ilumu
1 1
M One trick that makes adding gearcase oil less messy is to install the
levellvent plug BEFORE removing the pump from the drainlfiller
opening and threading the drainlfiller plug back into position.
10. Using new gaskets (usually plastic or fiber washers) install the oil
levellvent plug first, then install the oil fill plug.
11. Wipe the excess oil from the lower unit and inspect the unit for leaks.
12. Place the used lubricant in a suitable container for transportation to
an authorized recycling facility.
Observe all applicable safety precautions when working around fuel.
Whenever servicing the fuel system, always work in a well-ventilated
area. Do not allow fuel spray or vapors to come in contact with a spark
or open flame. Do not smoke while working around gasoline. Keep a
dry chemical fire extinguisher near the work area. Always keep fuel in a
container specifically designed for fuel storage; also, always properly
seal fuel containers to avoid the possibility of fire or explosion.
A fuel filter is designed to keep particles of dirt and debris from entering
the carburetor(s) or the fuel injection system and clogging the tiny internal
passages of each. A small speck of dirt, rust, gunk from a dirty tank or sand
can drastically affect the ability of the fuel system to deliver the proper
amount of air and fuel to the engine. If a filter becomes clogged, the flow of
gasoline will be impeded. This could cause lean fuel mixtures, hesitation and
stumbling and idle problems in carburetors. Although a clogged fuel passage
in a fuel injected engine could also cause lean symptoms and idle problems,
dirt can also prevent a fuel injector from closing properly. A fuel injector that
is stuck partially open by debris will cause the engine to run rich due to the
unregulated fuel constantly spraying from the pressurized injector.
Regular inspection, cleaning (if serviceable) or replacement (if not
serviceable) of the fuel filter will decrease the risk of blocking the flow of fuel
to the engine, which could leave you stranded on the water. It will also
decrease the risk of damage to the small passages of a carburetor or fuel
injector that could require more extensive and expensive replacement. Keep
in mind that fuel filters are usually inexpensive and replacement is a simple
task. Service your fuel filter on a regular basis to avoid fuel delivery
problems.
The type of fuel filter used on your engine will vary not only with the year
and model, but it can also vary with the accessories and rigging. Because of
the number of possible variations it is impossible to say with certainty what
filter you MAY find on the boat itself, but we can give you a good idea of the
filter that Suzuki put on the powerhead.
In addition to the fuel filter mounted on the engine, a filter or sock is often
found inside or the fuel tank and some boat manufacturers or dealers will rig
a boat with an additional water separating fuel filter inline between a built-in
fuel tank and the motor. Because of the large variety of differences in both
portable and fixed fuel tanks, it is impossible to give a detailed procedure for
removal and installation. Most in-tank filters are simply a screen on the pick-
up line inside the fuel tank. Filters of this type usually only need to be
cleaned and returned to service (assuming they are not torn or otherwise
damaged). Fuel filters on the outside of the tank are typically either of the
inline type (which are replaced by simply removing the clamps, disconnecting
the hoses and installing a new filter) or look like automotive spin-on oil filters
(water separating fuel filters). When installing a new inline filter, make sure
the arrow on the filter points in the direction of fuel flow.
To determine for certain what filter(s) are utilized by your boat and motor
rigging, trace the fuel line from the tank to the fuel pump and then from the
pump to the carburetors (or vapor separator tank).
SERVICING LOW-PRESSURE FUEL FILTERS
Observe all applicable safety precautions when working around fuel.
Whenever servicing the fuel system, always work in a well-ventilated
area. Do not allow fuel spray or vapors to come in contact with a spark
or open flame. Do not smoke while working around gasoline. Keep a
dry chemical fire extinguisher near the work area. Always keep fuel in a
container specifically designed for fuel storage; also, always properly
seal fuel containers to avoid the possibility of fire or explosion.
In all cases, inspect the filter at least annually, every 50 hours of operation
or if problems are suspected with the low-pressure circuit. Regardless, the
filter should be cleaned (if serviceable) or replaced by every 400 hours or bi-
annually.
2.5 Hp Models
See Figure 89
It should be no surprise that the smallest and simplest Suzuki motor also
contains the simplest of the fuel filter assemblies. On these motors there is a
small, inline, filter element installed between the tank fuel outlet and the fuel
petcock valve. Service should be a relatively simple manner of carefully
disconnecting the fuel valve from the tank (it's a single bolt) but this is best
done with the tank empty and removed. For more details, please refer to
Integral Fuel Tanks, under Fuel Tank in the Fuel System section.
As whenever you are working around fuel be sure to carefully check for
fuel leaks after the service is completed and before the motor is returned to
use.
4-15 Hp Models
See Figures 90 and 91
These models are normally equipped with a simple, non-serviceable inline
filter which can be inspected through the partially translucent filter body and
simply replaced if it is suspect. The filter on these models is normally found
on the fuel inlet line between the tank and the fuel pump. This puts it at the
front starboard side of the powerhead on 41516 hp motors, or on the rear port
side of the motor for 9.9115 hp models. On the 9.9115 hp model the filter is
behind the port lower engine side cover, and removing the cover usually
posable inline filter used on 41516 Fig. 91 Disposable inline filter used on
9.9115 hp motors
makes access a lot easier, though we find it is not absolutely necessary.
Because of the relative ease and relatively low expense of a filter (when
compared with the time and hassle of a carburetor overhaul) we encourage
you to service the filter at least bi-annually.
When replacing a disposable filter, release the hose clamps (they are
usually equipped with spring-type clamps that are released by squeezing the
tabs using a pair of pliers, though some might used crimped-type clamps
which must be cut away and replaced), then slide them back on the hose,
past the raised portion of the filter inleVoutlet nipples. Once a clamp is
released, position a small drain pan or a shop towel under the filter and
carefully pull the hose from the nipple. Allow any fuel remaining in the filter
and fuel line to drain into the drain pan or catch fuel with the shop towel.
Repeat on the other side of the filter, noting which fuel line connects to which
portion of the filter (for assembly purposes). Inline filters are usually marked
with an arrow indicating fuel flow. The arrow should point towards the fuel
line that runs to the motor components (not the fuel tank).
Before installation of the new filter, make sure the hoses are in good
condition and not brittle, cracking and otherwise in need of replacement.
During installation, be sure to fully seat the hoses, then place the clamps
over the raised portions of the nipples to secure them. Spring clamps will
weaken over time, so replace them if they've lost their tension. If wire ties or
adjustable clamps were used, be careful not to overtighten the clamp. If the
clamp cuts into the hose, it's too tight; loosen the clamp or cut the wire tie
(as applicable) and start again.
When you are finished, be sure to pressurize the fuel system using the
fuel primer bulb from the tank line and check for leaks. Observe the fuel
hose fittings for fuel leakage and repair any fuel leaks before starting the
motor. Clean up any spilled fuel.
25/30 Hp 3-Cyl and 40-70 Hp Models
See Figures 92 and 93
MOST of these models are equipped with a non-serviceable, inline
canister filter which can be inspected through the partially translucent filter
body and replaced if it is suspect. We say MOST however, because even
tno~ignsome of the Suzuki factory literature suggests otherwise we've seem
some exceptions where a serviceable version of this filter (one with a drain
nipple and sealing cap toward the bottom of the canister) has been used on
some of these motors, and it is our belief that you COULD find this type of
filter on any of these models.
If inspection shows that you have a serviceable variant with a drain
nipple on these motors, no big deal, just refer to the additional
information found under the 25 Hp190-175 Hp procedure later in this
section.
Like most Suzuki low-pressure fuel filters, the filters on these models is
normally found inline, between the fuel inlet fitting and the fuel pump. Exact
location may vary slightly, but that generally puts it in a bracket toward the
rear starboard side of the motor. For MOST of these models the filter is
located at a point above the engine cover to that there is no need to remove
the cover for access, but on some the filter may be fully or partially obscured
by the cover and removal may make things easier.
o--^,..--,. ? 5e relative ease and relatively low expense of a filter (when
. .
compared with the time and hassle of a carburetor overhaul) we encourage
you to service the filter at least bi-annually.
These filters may also be labeled with arrows showing fuel flow, but
why take the risk, note the hose positions before disconnecting
anything.
When replacing a disposable filter of this type the fuel line nipples are
usually located on the same side of the filter so it is important to note which
hose connects to which nipple before proceeding. There may be exceptions,
but generally speaking the inlet hose (from the fuel supply fitting) connects to
the lower nipple while the fuel outlet hose (which goes to the fuel pump)
connects to the upper nipple.
Also like the smaller motors covered earlier, the fuel hoses are normally
retained on these nipples by spring-type hose clamps. To disconnect the
hoses, release the hose clamps by squeezing the tabs using a pair of pliers,
then slide them back on the hose, past the raised portion of the filter
inletloutlet nipples. Once a clamp is released, position a small drain pan or a
shop towel under the filter and carefully pull the hose from the nipple. Allow
any fuel remaining in the filter and fuel line to drain into the drain can or
catch fuel with the shop towel. Repeat on the other nipple.
Before installation of the new filter, make sure the hoses are in good
condition and not brittle, cracking and otherwise in need of replacement.
During installation, be sure to fully seat the hoses, then place the clamps
over the raised portions of the nipples to secure them. Spring clamps will
weaken over time, so replace them if they've lost their tension. If wire ties or
adjustable clamps are used, be careful not to overtighten the clamp. If the
clamp cuts into the hose, it's too tight; loosen the clamp or cut the wire tie
(as applicable) and start again.
When you are finished, be sure to pressurize the fuel system using the
fuel primer bulb from the tank line and check for leaks. Observe the fuel
hose fittings for fuel leakage and repair any fuel leaks before starting the
motor. Clean up any spilled fuel.
25 Hp V2 and 90-175 Hp Models
See Figures 94 and 95
Most of these motors are equipped with a partially serviceable, inline,
canister filter which is VERY similar to the one found on most 25/30 hp 3-cyl
and 40-70 hp models, the one difference being that instead of just two fuel
hose nipples (one inlet and one outlet) these filters NORMALLY also have an
additional drain nipple toward the bottom of the canister.
H We say NORMALLY have because once again the service literature
and models we've seen in the field don't always agree, but IF they don't
have the serviceable nipple it is no big deal, it just means the whole
canister must be replaced the same way as the serviceable ones.
To service this type of filter, remove it from the powerhead and remove
the cap from the lower nipple. Drain the fuel (and any debris) from the
bottom of the filter. If necessary, use a length of hose to pour some fuel back
in through the top (fuel OUTLET) nipple to back flush debris from the filter
element and out the drain at the bottom. Obviously, upon reinstallation make
sure the cap on the bottom of these filters is secure otherwise you risk
dangerous fuel leaks.
Now like many of the smaller models, access to the filter itself is usually
pretty straight forward (i.e. you usually don't have to remove the lower
engine covers, but if you find one where you have to, again, no big deal).
Keep in mind that on 1501175 hp motors the filter is located under its own
protective cover which must be removed for access to the filter. To remove
this cover gently grab it and pull the TOP OF THE COVER OUTWARD and
then lift upward to free the cover from the powerhead.
Also like most of the smaller models the INLET fuel line (from the fuel
supply) is usually mounted lower on the filter assembly than the OUTLET
fuel line (like to the Vapor Separator Tank). However, just to be sure, always
note the fuel line positions before they are disconnected. The lines
themselves are secured with spring-type clamps, so to loosen them simply
squeeze the tabs with a pair of pliers and slide the clamps back up the hose
until it is past the nipple. Have a rag or drain pan handy to catch any
escaping fuel and gently disconnect the fuel lines.
ALWAYS inspect the fuel lines for brittleness or cracking and replace
any that show signs of deterioration. The LAST thing you want out on
the water is an unexpected fuel leak! Same goes for the hose clamps,
replace any that are weak or have lost their spring.
When you are finished, be sure to pressurize the fuel system using the
fuel primer bulb from the tank line and check for leaks. Observe the fuel
hose fittings for fuel leakage and repair any fuel leaks before starting the
motor. Clean up any spilled fuel.
200-300 Hp Models
See Figure 96
The V6 motors covered here utilize a full-serviceable inline low-pressure
fuel filter. The filter element itself is mounted inside a housing that can be
opened so the element can be removed, inspected, cleaned in solvent and
either returned to service or replaced, as necessary.
Though the element should not require very frequent service, it should be
visually checked each and every time the top cover comes off the motor. The
filter housing contains a RED indicator float which surrounds the filter
element and will rise (float) in the presence of water. Whenever the red float
is UP the filter cap should be removed so the water can be drained.
To drain water or remove the element for cleaning, inspection and/or
replacement, proceed as follows:
1. Disconnect the negative battery cable for safety.
A lockring is used to secure the filter housing (cup) to the filter head
(cap). Because of this you SHOULD be able to leave the hoses attached
while removing the housing and element, but in some instances the
additional playlaccess that comes from disconnecting the hoses can be
handy.
2. If necessary in order to reposition the housing, tag and disconnect
the 2 hoses attached to the top of the fuel filter assembly (the cap or filter
head). The factory usually secures these fuel lines with spring-type hose
clamps. Squeeze the clamp tabs and hold while sliding the clamps up the
hose, past the raised nipple on the fitting. If other threaded clamps are used,
loosen and slide them back. If wire ties were used, they must be cut away
carefully, making sure not to damage the hose. Inspect all metallic clamps for
corrosion, lack of spring tension and/or other damage. Replace any faulty or
questionable hose clamps.
3. Also, if necessary for better access, remove the 2 bolts securing the
low-pressure fuel filter to the bracket, then remove the entire fuel filter
assembly from the assembly.
4. Position a container or shop rag below the fuel filter. Loosen the ring
nut which secures the filter housing to the filter head, then carefully separate
the two.
5. Remove the large O-ring which secures the housing to the head,
then remove the filter element and the small O-ring which seals the element
to the head.
6. Clean the filter using a suitable solvent, then blow it dry with low
pressure compressed air (or allow it to air dry). Inspect the element of
serviceable filters for clogs or tears and replace if damaged. Take a GOOD
look at the O-rings and replace them if they are cut, worn or otherwise
damaged.
To install:
7. Assemble the filter element into the filter head using a small O-ring,
then position the large O-ring and connect the filter housing to the head. Use
the ring nut to secure the housing.
8. If removed, reposition the filter to the powerhead and tighten the
retaining bolts.
9. If removed, reconnect the fuel lines as noted or tagged during
removal. Secure the hoses using the spring clamps. If using wire ties or
threaded clamps as replacements, be sure not to over-tighten the clamps,
cutting the hoses.
10. Pressurize the fuel system using the fuel primer bulb from the tank
line and check for leaks. Observe the fuel hose fittings for fuel leakage and
repair any fuel leaks before starting the motor. Clean up any spilled fuel.
SERVICING HIGH-PRESSURE FUEL FILTERS
(EFI MOTORS ONLY)
@ See Figure 97
Observe all applicable safety precautions when working around fuel.
Whenever servicing the fuel system, always work in a well-ventilated
area. Do not allow fuel spray or vapors to come in contact with a spark
or open flame. Do not smoke while working around gasoline. Keep a
dry chemical fire extinguisher near the work area. Always keep fuel in a
container specifically designed for fuel storage; also, always properly
seal fuel containers to avoid the possibility of fire or explosion.
Suzuki fuel injected motors are equipped with two interrelated fuel circuits,
the high-pressure and low-pressure systems. The low-pressure system
operates essentially the same way as does a 4-stroke carbureted motor's
Fig. 92 Typical disposablelnon-serviceable Fig. 93 Another example of a non- Fig. 94 View of a serviceable inline canister
inline filter (25130 hp 3-cyl shown) serviceable inline filter (40150 hp shown) filter
I I I 1
Element
fuel system. A mechanical, engine mounted fuel pump draws fuel from the
tank and feeds a mechanical float controlled fuel reservoir. The difference
occurs at this point as the reservoir is for the high-pressure circuit and
electric high-pressure pump instead of a float bowl attached to a carburetor.
These motors usually contain at least 3 fuel filters, two of these filters are
inline and are replaced during normal service. One inline filter is used for
each fuel circuit (the Low-Pressure one was covered earlier in this section)
and the High-pressure on is covered here.
The high-pressure circuit is protected by an inline filter canister found
between the high-pressure pump (in the vapor separator tank) and the fuel
rail assembly.
An additional filter screen is mounted on the electric high-pressure fuel
wmo inlet. Althouah this screen can be reolaced, it is not normallv Dart of
maintenance. ~he"~um~
filter screen can only be replaced once the pump is
removed from the vapor separator. Depending on the boat rigging, additional
inline filters or tank filter screen may also be present.
To avoid the possibility of fire and personal injury, always disconnect the
negative battery cable while servicing the fuel system or fuel system
components.
Always place a shop towel or cloth around the fitting or connection prior to
loosening to absorb any excess fuel due to spillage. Ensure that all fuel
spillage is removed from engine surfaces.
On fuel injected engines, always relieve system pressure prior to
disconnecting any high-pressure fuel circuit component, fitting or fuel line.
For details, please refer to Fuel System Pressurization under Fuel Injection.
Exercise extreme caution whenever relieving fuel system pressure to
avoid fuel spray and potential serious bodily injury. Please be advised
that fuel under pressure may penetrate the skin or any part of the body
it contacts.
The canister itself is attached somewhere near the VST (usually right
above it or next to it, but on 60170 hp motors, it's right below the VST). To
locate the canister, take a look in the following areas, depending upon the
model:
On 40150 hp motors the canister can be found at the top of the
powerhead, on the port side, just above the intake.
On 60170 hp motors the canister is also on the port side, but toward
the center at the bottom of the powerhead (just below and inboard of the
intake manifold.
* On 90-140 hp motors the canister is on the starboard side of the
powerhead, a little more than halfway back, just inboard and slightly above
the intake manifold.
On 1501175 hp motors the canister is on the aft end of the powerhead,
bolted vertically directly above the VST assembly at the end of the intake
manifold.
* On 200-300 hp V-motors the canister is toward the top, front port-side
of the powerhead. directly above the VST assembly.
Pig. 97 Typical High-pressure fuel filter
(mounting varies) -40150 hp shown
1. Properly relieve the fuel system pressure as described in Fuel
System Pressurization under the Fuel Injection section, then disconnect the
negative battery cable for safety.
en if you leave the fuel pump wiring harness disconnected (part of
e fuel pressure relief procedure on most models) it is still a good idea
disconnect the negative battery cable. Remember that sparks are a
ngerous source of ignition that could ignite fuel vapors and by
removing battery power from the engine components you help
minimize the possibility of causing sparks while working on the motor.
2. If necessary on 60170 hp models, remove the lower engine cover for
access, as described in this section under Engine Cover.
H The filter canister is normally embossed with markings (IN and OUT)
indicating where the fuel line comes IN from the pump or the line OUT
to the fuel rail attach. With this said, we would still advice tagging the
fuel lines prior to removal to help ensure ease of connection during
filter installation. Remember, the line from the VST should attach to the
IN fitting of the filter, while the line which goes out to the fuel injectors
should attach to the OUT fitting,
3, Tag the fuel hoses and note the filter positioning, then remove the
clamps and carefully pull the hoses from the fittings on each end of the filter.
Drain any residual fuel from the hoses.
4. Remove the filter from the powerhead (on some models it may be
necessary to remove the retaining bollfbolts from the bracket first). Drain
residual fuel from the filter.
To install:
5. Position the filter as noted during removal, carefully seat the hoses
over the fittings and secure using the clamps. Make sure any spring-type
clamps used have not lost their tension. If threaded clamps or wire ties are
used, they should be snug, but not tight enough to cut the hose.
M Upon installation, be certain to connect the hoses as tagged during
removal. The hose from the fuel pump connects to the IN fitting, while
the fuel rail hose connects to the fitting marked OUT. If the hoses were
repositioned while servicing the filter, make sure they are routed as
they were prior to removal. This will help ensure that there will be no
interference with parts of the motor that could damage the hoses
through heat or contact.
6. Secure the filter by tightening the mounting bolt(s).
7. Connect the negative battery cable and either reinstall the fuel pump
fuse or reconnect the pump wiring harness (as applicable) then pressurize
the fuel system and check for leakage before starting the motor. For details,
refer to Fuel System Pressurization, under Fuel System.
8. Once you are assured there are no leaks you can reinstall the engine
top cover. Of course, on 60170 hp motors, if you've removed the lower
engine cowling, you'll have to install that first.
motors are equipped with a number of breather and/or fuel supply
lines. As stated earlier under BeforeIAfter Each Use all of these hoses
should be checked visually each time you go out. However, at least once per
year you should perform a more thorough check of these hoses. Get to know
how hard or soft they are when new so that you can help spot when they
have become dried outlbrittle or softened and ready to perforate.
Breather hoses interconnect parts of the crankcase and usually the intake
tract. The function of a breather hose is to control the vacuum/~ressure
created inside the motor by the Otto cycle. On all motors when equipped
these hoses should be carefully checked at least once a year, however on
most motors these hoses are listed as a periodic (bi-annual) replacement
item to prevent problems. Honestly, we think most people probably wait until
they find the hose is brittlelcracking or is collapsing before they replace
them, but they are mentioned in the manufacturer maintenance tables and
thought we at least had to bring it up here. Use your best judgment when
deciding when (or when not) to replace any hoses. If anything we'd replace
fuel hoses more often, because a crackleak can be a much bigger deal on a
fuel hose than a breather hose.
See Figures 98,99 and 100
The propeller is secured to the gearcase propshaft either by a cotter pin
on the smallest outboards only (2.5-6 hp motors), or by a castellated hex nut
on all other Suzuki motors.
For models secured by a hex nut, the propeller is driven by a splined
connection to the shaft and the rubber drive hub found inside the propeller.
The rubber hub provides a cushioning that allows softer shifts, but more
importantly, it provides some measure of protection for the gearcase
components in the event of an impact.
On motors where the propeller is retained by a cotter pin, the propeller is
actually DRIVEN by a shear or drive pin (which the propeller is mounted over
top of) and impact protection is normally provided by the drive pin itself. The
pin is designed to break or shear when a specific amount of force is applied
because the propeller hits something. In both cases (rubber hubs or shear
pins) the amount of force necessary to break the hub or shear the pin is
supposed to be just less than the amount of force necessary to cause
gearcase component damage. In this way, the hope is that the propeller and
hub or shear pin will be sacrificed in the event of a collision, but the more
expensive gearcase components will survive unharmed. Although these
systems do supply a measure of protection, this, unfortunately, is not always
the case and gearcase component damage will still occur with the right
impact or with a sufficient amount of force.
Because the 90-300 hp motors use an offset crankshaft with a
separate crankshaft driven gear the MOTORS were designed to rotate
COUNTERCLOCKWISE (or Left-Hand) in order to drive the driven gear
and driveshaft the same standard CLOCKWISE direction that other
motors rotate. In this way the gearcases for these Left-Hand turning
powerheads can still utilize standard Right-Hand (standard rotation)
propellers.
INSPECTION
See Figures 98,99 and 100
The propeller should be inspected before and after each use to be sure
the blades are in good condition. If any of the blades become bent or nicked,
this condition will set up vibrations in the motor. Remove and inspect the
propeller. Use a file to trim nicks and burrs. Take care not to remove any
more material than is absolutely necessary.
Never run the engine with serious propeller damage, as it can allow for
excessive engine speed and/or vibration that can damage the motor.
Also, a damaged propeller will cause a reduction in boat performance
and handlina.
Also, check the rubber and splines inside the propeller hub for damage. If
there is damage to either of these, take the propeller to your local marine
dealer or a "prop shop". They can evaluate the damaged propeller and
determine if it can be saved by rehubbing.
Additionally, the propeller of splined shaft models (though the shear pin
models should be greased too, just to be sure) should be removed AT
LEAST everv 200 hours of ooeration or at the end of each season.
whichever comes first for cleaning, greasing and inspection. whenever the
propeller is removed, apply a fresh coating of Suzuki Water Resistant
Grease or an equivalent water resistant, marine grease to the propeller shaft
and the inner diameter of the propeller hub. This is necessary to prevent
possible propeller seizure onto the shaft that could lead to costly or
troublesome repairs. Also, whenever the propeller is removed, any material
entanoled behind the orooeller should be removed before anv damaae to the
shaft and seals can occur. This may seem like a waste of time at firs?, but
the small amount of time involved in removing the propeller is returned many
times by reduced maintenance and repair, including the replacement of
expensive parts.
Propeller shaft greasing and debris inspection should occur more
often depending upon motor usage. Frequent use in salt, brackish or
polluted waters would make it advisable to perform greasing more
often. Similarly, frequent use in areas with heavy marine vegetation,
debris or potential fishing line would necessitate more frequent
removal of the propeller to ensure the gearcase seals are not in danger
of becoming cut.
REMOVAL & INSTALLATION
Do not use excessive force when removing the propeller from the hub
as excessive force can result in damage to the propeller, shaft and,
even other gearcase components. If the propeller cannot be removed
by normal means, consider having a reputable marine shop remove it.
The use of heat or impacts to free the propeller will likely lead to
damage.
Fig. 98 This propeller is long overdue for Fig. 99 Although minor damage can be Fig. 100 . . .a propeller specialist should
repair or replacement dressed with a file. . . repair large nicks or damage
Clean and lubricate the propeller and shaft splines using a high-
quality, water resistant, marine grease every time the propeller is
removed from the shaft. This will help keep the hub from seizing to the
shaft due to corrosion (which would require special tools to remove
without damage to the shaft or gearcase.)
Many outboards are equipped with aftermarket propellers. Because of
this, the attaching hardware may differ slightly from what is shown. Contact a
reputable propeller shop or marine dealership for parts and information on
other brands of propellers.
2.5-6 Hp Motors
+ See Figures 101 and 102
The propeller on all 2.5-6 hp motors is secured to the propshaft using a
cotter pin, which either mounts directly through the end of the propeller (2.5
ho) or mounts throuah a separate propeller "nut" which fits over the end of
. .
the propeller.
In addition to the cotter pin, the rotational force of the propeller shaft is
transmitted to the propeller itself throuah a shear pin (drive pin) which is
positioned through the prop shaft underneath the propeller. the propeller is
positioned over top of the propeller shaft and drive pin.
Be sure to always keep a spare cotter pin and drive pin handy when you
are onboard the boat. Remember that a sheared drive pin will leave you
stranded on the water. A damaged shear pin can also contribute to motor
damage, exposing it to over-rewing while trying to produce thrust. And a
damaged or missing cotter pin could allow the propeller shaft to literally fall
off the end of the drive pin.
Fig. 101 View of the mounted propeller on a 41516 hp gearcase
1. Cotter pin
2. Propeller nu1
3. Propeller
4. Shear pin
Fig. 102 Propeller mounting -41516 hp motors (2.5 hp the same, but
without a separate propeller nut)
ALWAYS replace the cotter pin once it has been removed. Remember
that should the cotter pin fail, you could be diving to recover your propeller.
1. Disconnect the negative battery cable or, more likely since these
motors are rarely equipped with batteries, disconnect the spark plug lead
from the plugs for safety.
Don't ever take the risk of working around the propeller if the engine
could accidentally be started. Always take precautions such as
disconnecting the spark plug lead and, if equipped, the negative battery
cable.
2. Cut the ends off the cotter pin (as that is easier than trying to
straighten them in most cases). Next, free the pin by grabbing the head with
a pair of needlenose pliers. Either tap on the pliers gently with a hammer to
help free the pin from the propeller cap or carefully use the pliers as a lever
by carefully prying back against the propeller cone. Discard the cotter pin
once it is removed.
3. On 41516 hp models, remove the propeller nut (end cap) from the end
of the propeller and prop shaft.
4. Get a hold of the propeller, then carefully pull it off the shaft and the
drive pin.
5. Grasp and remove the drive pin using the needlenose pliers.
If the drive pin is difficult to remove, use a small punch or a new
drive pin as a driver and gently tap the pin free from the shaft.
To install:
6. Clean the propeller hub and shaft splines, then apply a fresh coating
of Suzuki Water Resistant Grease or an equivalent water resistant, marine
grease.
7. Insert the drive pin into the propeller shaft.
8. Align the propeller, then carefully slide it over the shaft and drive pin.
9. On 41516 hp models install the propeller nut (end cap).
10. Install a new cotter pin, then spread the pin ends in order to form
tension and secure them. Do not bend them over too far as the pin will
loosen and rattle in the shaft.
9.9 hp and Larger Motors
+ See Figures 103 thru 107
B Because the 90-300 hp 4-strokes use an offset crankshaft with a
separate crankshaft driven gear the motors were designed to rotate
COUNTERCLOCKWISE in order to drive the driven aear and driveshaft
the same standard CLOCKWISE direction that othermotors rotate. in
this way the gearcases for these Left Hand turning powerheads can
still utilize standard Right Hand (standard rotation) propellers.
Most Suzuki motors (meaning everything currently 9.9 hp and larger) use
a slotted or castellated nut (so named because, when viewed from the side,
it appears similar to the upper walls or tower of a castle) to secure the
propeller to the propeller shaft. A cotter pin is placed through the slots in the
nut in order to lock it in place and prevent the possibility of it loosening or
backing off in service.
In addition to the cotter pin, castellated nut and the nut washer, there is
normally a spacer mounted between the washer and propeller, and a thrust
washer mounted between the propeller and gearcase. The design of most
Suzuki propeller spacers and thrust washers incorporate both a flat side and
a stepped or shouldered side. Pay attention to this during disassembly, but in
every illustration we've seen by Suzuki the stepped shoulders are faced
toward the propeller while the flat shoulders are faced outward (toward the
gearcase or castellated nut respectively).
The only other difference between models is in the torque spec, which
varies with the size of the propshaft and nut. The torque specifications for
prop nuts are as follows:
9.9115 hp and 25/30 hp (3-cyl) motors: 156 inch lbs.113 ft. Ibs. (18
Nm)
25 hp V2 motors: 217 inch lbs.118 ft. Ibs. (24.5 Nm)
40 hp and larger motors: 40 ft. Ibs. (55 Nm)
Again, the nut is locked in place by a cotter pin to ensure that it cannot
loosen while the motor is running. The pin passes through a hole in the
propeller shaft, as well as through the notches in the sides of the castellated
nut. Install a new cotter pin anytime the propeller is removed and, perhaps
more importantly, make sure the cotter pin is of the correct size and is made
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Fig. 104 Use a block of wood to keep the
Fig. 105 Note the orientation of the spacer
and thrust washer (the stepped shoulders
Fig. 106 Tighten the castellated nut and install a new cotter pin
of materials designed for marine use. Make sure that you include the cotter
pin in all pre- and post-launch checks.
Whenever working around the propeller, check for the presence of black
rubber material (not to be confused with traces of black carbon from the
exhaust) in the drive hub and spline grease. Presence of this material
normally indicates that the hub has turned inside the propeller bore (have the
propeller checked by a propeller repair shop). Keep in mind that a spun hub
will not allow proper torque transfer from the motor to the propeller and will
allow the engine to over-rev in order to produce thrust (or will just over-rev
producing little or no thrust). If the propeller has spun on the hub it has been
weakened and is more likely to fail completely in use.
1. For safety, disconnect the negative battery cable (if so equipped)
and/or disconnect the spark plug [email protected]) from the plug(s) and ground the
leads to prevent possible ignition damage should ihe motor be cranked at
some point before the [email protected]) are reconnected to the spark plug(s).
Don't ever take the risk of working around the propeller if the engine
could accidentally be cranked or started. Always take precautions such
as disconnecting the spark plug leads and, if equipped, the negative
battery cable.
2. Cut the ends off the cotter pin (as that is easier than trying to
straighten them in most cases). Next, free the pin by grabbing the head with
a pair of needlenose pliers. Either tap on the pliers gently with a hammer to
help free the pin from the nut or carefully use the pliers as a lever by prying
back against the castellated nut. Discard the cotter pin once it is removed.
Fig. 107 Notice the cotter pin is gently spread, NOT bent 90' or
more
3. Place a block of wood between the propeller and the anti-ventilation
housing to lock the propeller and shaft from turning, then loosen and removc
the nut. Note the orientation, then remove the washer and the spacer from
the propeller shaft.
4. Slide the propeller from the shaft. If the prop is stuck, use a block of
wood to prevent damage and carefully drive the propeller from the shaft.
 If the propeller is completely seized on the shaft, start by soaking it
with a good penetrating lubricant like PB Blaster(r) and give it some
time to work in. After multiple applications you'll have to decide if you
should use a threaded puller, heat or impact to proceed, but keep in
mind that you're going to AT LEAST damage the propeller and
potentially the gearcase, so proceed with caution. At worst case
scenario, cut the rubber hub and remove the propeller, then work on
getting the inner hub shaft off the prop shaft.
5. Note the direction in which the thrust washer is facing (the
shouldered portion is normally positioned facing the propeller). Remove the
thrust washer from the propshaft (if the washer appears stuck, tap lightly to
free it from the propeller shaft). Also keep in mind that this washer
sometimes comes off with the propeller so if it's not there, check the front of
the prop hub before you panic.
6. Clean the thrust washer, propeller and shaft splines of any old
grease. Small amounts of corrosion can be removed carefully using steel
wool or fine grit sandpaper.
7, Inspect the shaft for signs of damage including twisted splines or
excessively worn surfaces. Rotate the shaft while looking for any deflection.
Replace the propeller shaft if these conditions are found. Inspect the thrust
washer for signs of excessive wear or cracks and replace, if found.
To install:
8. Apply a light coat of Suzuki Water Resistant Grease or equivalent
high-quality, water resistant, marine grease to all surfaces of the propeller
shaft and to the splines inside the propeller hub.
9. Position the thrust washer over the propshaft in the direction noted
during removal.
10. Carefully slide the propeller onto the propshaft, rotating the propeller
to align the splines. Push the propeller forward until it seats against the
thrust washer.
11. Install the spacer onto the propeller shaft, as noted during removal
(normally with the shoulder facing the propeller).
12. Position the flat washer over the propeller shaft and against the
spacer.
13. Place a block of wood between the propeller and housing to hold the
prop from turning, then thread the nut onto the shaft. When threading a
castellated nut, make sure the cotter pin grooves facing outward.
14. Tighten the nut to specification, as listed earlier in this section.
15. Install a new cotter pin through the grooves in the nut or the keeper
as applicable) that align with the hole in the propshaft. If the cotter pin hole
and the grooves do not align, tighten the nut additionally, just enough to align
them (do not loosen the nut from specification to achieve alignment.) Once
the cotter pin is inserted, spread the ends sufficiently to lock the pin in place.
Do not bend the ends over at 90' or greater angles as the pin will loose
tension and rattle in the slot.
16. Connect the spark plug lead(s) and/or the negative battery cable, as
applicable.
GENERAL INFORMATION
See Figure 108
A jet drive motor uses an impeller enclosed in a jet drive housing instead
of the propeller used by traditional gearcases. Outboard jet drives are
designed to permit boating in areas prohibited to a boat equipped with a
conventional propeller outboard drive system. The housing of the jet drive
barely extends below the hull of the boat allowing passage in ankle deep
water, white water rapids, and over sand bars or in shoal water which would
foul a propeller drive.
The outboard jet drive provides reliable propulsion with a minimum of
moving parts. It operates, simply stated, as water is drawn into the unit
through an intake grille by an impeller. The impeller is driven by the
driveshaft off the powerhead's crankshaft. Thrust is produced by the water
that is expelled under pressure through an outlet nozzle that is directed away
from the stern of the boat.
As the speed of the boat increases and reaches planing speed, only the
very bottom of the jet drive where the intake grille is mounted facing
downward remains in contact with the water.
The jet drive is provided with a reverse-gate arrangement and linkage to
permit the boat to be operated in reverse. When the gate is moved
downward over the exhaust nozzle, the pressure stream is deflected
(reversed) by the gate and the boat moves sternward.
Conventional controls are used for powerhead speed, movement of the
boat, shifting and power trim and tilt.
INSPECTION
+ See Figure 109
The jet impeller is a precisely machined and dynamically balanced
aluminum spiral. Close observation will reveal drilled recesses at exact
locations used to achieve this delicate balancing. Excessive vibration of the
jet drive may be attributed to an out-of-balance condition caused by the jet
impeller being struck excessively by rocks, gravel or from damage caused by
cavitation "burn".
The term cavitation "burn" is a common expression used throughout the
world among people working with pumps, impeller blades, and forceful water
movement. These "burns" occur on the jet impeller blades from cavitation air
bubbles exploding with considerable force against the impeller blades. The
edges of the blades may develop small dime-size areas resembling a porous
sponge, as the aluminum is actually "eaten" by the condition just described.
Fig. 108 Suzuki 115 hp motor rigged with a jet drive
Excessive rounding of the jet impeller edges will reduce efficiency and
performance. Therefore, the impeller and intake grate (that protects it from
debris) should be inspected at regular intervals.
Before and after each use. make a auick visual inspection of the intake
grate and impeller, looking for obvious signs of damage. Always clear any
debris such as plastic bags, vegetation or other items that sometimes
become entangled in thewaterntake grate before starting the motor. If the
intake grate is damaged, do not operate the motor, or you will risk destroying
the impeller if rocks or other debris are drawn upward by the jet drive. If
possible, replace a damaged grate before the next launch. This makes
inspection after use all that much more important. Imagine the
disappointment if you only learn of a damaged grate while inspecting the
motor immediately prior to the next launch.
An obviously damaged impeller should be removed and either repaired or
replaced depending on the extent of the damage. If rounding is detected, the
impeller can be placed on a work bench and the edges restored to as sharp
a condition as possible, using a file. Draw the file in only one direction. A
back-and-forth motion will not produce a smooth edge. Take care not to nick
the smooth surface of the jet impeller. Excessive nicking or pitting will create
water turbulence and slow the flow of water through the pump. For more
details on impeller replacement or service, please refer to the information on
Jet Drives in the Gearcase section of this service.
CHECKING IMPELLER CLEARANCE
DERATE
@ See Figures 110 and 111
Proper operation of the jet drive depends upon the ability to create
maximum thrust. In order for this to occur the clearance between the outer
edge of the jet drive impeller and the water intake housing cone wall should
be maintained at approximately 0.020-0.030 in. (0.5-0.8mm). This distance
can be checked visually by shining a flashlight up through the intake grille
and estimating the distance between the impeller and the casing cone, as
indicated in the accompanying illustrations. But, it is not humanly possible to
accurately measure this clearance by eye. Close observation between
outings is fine to maintain a general idea of impeller condition, but, at least
annually, the clearance must be measured using a set of feeler gauges.
Although some gauges may be long enough to make the measurement with
the intake grate installed, removal is advised for access and to allow for a
more thorough inspection of the impeller itself.
Fig. 109 Visually inspect the Intake grate
Fig. 110 Jet drive impeller clearance is the
gap between the edges of the impeller and
Fig. 111 Impeller clearance is adjusted by
moving shims from below to above the
and impeller with each use its housing impeller
Whenever working around the impeller, ALWAYS disconnect the
negative battery cable and/or disconnect the spark plug leads to make
sure the engine cannot be accidentally started during service. Failure
to heed this caution could result in serious personal injury or death in
the event that the engine is started.
When checking clearance, a feeler gauge larger than the clearance
specification should not fit between the tips of the impeller and the housing.
A gauge within specification should fit, but with a slight drag. A smaller gauge
should fit without any interference whatsoever. Check using the feeler gauge
at various points around the housing, while slowly rotating the impeller by
hand.
After continued normal use, the clearance will eventually increase. In
anticioation of this the manufacturer mounts the taoered imoeller deeo in a
its housing, and positions spacers beneath the impeller to hold it in position.
The spacers are used to position the impeller along the driveshaft with the
desired clearance between the jet impeller and the housing wall. When
clearance has increased, spacers are removed from underneath the impeller
and repositioned behind it, dropping the impeller slightly in the housing and
thereby decreasing the clearance again. Moving 1 spacer will decrease
clearance approximately 0.004 in. (0.10mm).
If adjustment is necessary, refer to the Jet Drive procedures under
Gearcase in this service for impeller removal, shimming and installation
procedures.
LOCATION & GENERAL INFORMATION
See Figures 112 thru 124
The idea behind anodes (also known as sacrificial anodes) is simple:
When dissimilar metals are dunked in water and a small electrical current is
leaked between or amongst them, the less-noble metal (galvanically
speaking) is sacrificed (corrodes) while the more-noble metal is preserved.
The zinc alloy of which the anodes are made is designed to be less noble
than the aluminum alloy of which your outboard is constructed. If there's any
electrolysis, and there almost always is, the inexpensive zinc anodes are
consumed in lieu of the expensive outboard motor.
These zincs require a little attention in order to make sure they are
capable of performing their function. Anodes must be solidly attached to a
clean mounting site. Also, they must not be covered with any kind of paint,
wax or marine growth.
The number and location of the anodes used will vary greatly by model
and rigging, so greatly it can be prohibitive to try and list them all here (but
we'll do our best). For starts, keep in mind that these motors may be
equipped with as few as one anode or as many as a DOZENor so and the
most common locations include:
Gearcase -probably EVERY outboard covered here has at LEAST
one anode on the gearcase.
a Exhaust Housing -at least some of the motors covered here are
equipped with an anode on the exhaust housing, generally right above the
aearcase solit-line.
"
~ransornBracket -most mid-range and larger motors will have one or
two anodes mounted to the bottom of the transom bracket, almost up against
the hull of the boat. These anodes may be bolted up from underneath, or
from the sides, sandwiched in between two ears at the bottom of the
clamping bracket. Some may use one or more additional small rounded
anodes as well.
Powerhead -some models will also have one or more anodes bolted
directly to parts of the powerhead. Generally speaking these anodes are
inserted into a bore on the powerhead designed specifically to accept the
anode.
For more specific anode locations, refer to the following list by motor.
HOWEVER, don't assume this list is complete as we've seen anodes on
motors that were not listed in the technical literature for that motor, so check
yourself.
2.5 hp motors -normally use one round anode on the starboard side of
the gearcase, right above the anti-cavitation plate.
41516 hp motors -are normally equipped with a small round anode on
the starboard side of the gearcase, right above the propeller and anti-
cavitation plate. In addition, they are usually also equipped with another
small round anode on the toward the front, port side of the exhaust housing,
right at the split line.
9.9115 hp motors -these motors vary slightly by year. For starters most
should have a single round anode under the anti-cavitation plate (right above
Fig. 113 All motors have at least one anode
on the lower unit, some are under the anti- Fig. 114 . . .or on top of it like this (9.9115 hp Fig. 115 On some motors the trim tab IS the
ventilation plate.. . shown) anode
Fig. 116 Anodes come in different shapes, Fig. 118 . . .but MOST are secured with a
some are round.. . Fig. 117 . . .while others are blocks. .. single bolt through the center
the propeller) right about where you would normally expect a trim tab. In
addition 2003 or later models should have a small, rounded, rectangular
anode on too of the anti-cavitation olate. toward the rear oort side of the
plate. ~ostly early-models through2002 should be equipped with an anode
at the bottom of the transom bracket. Lastly, 2005 or later models should be
equipped with one under a cover bolted to the top, starboard side of the
powerhead, just a little in front of the oil fill cap and directly underneath a
breather hose (as a matter of fact the same bolt that retains the cover also
secures a hose clamp). In addition, most of these models will be equipped
with one or two bonding wires.
* 25 hp V2 motors -are normally equipped with about 8 different
anodes. For starters there should be one in the form of a trim tab. There
should be 4 small, round anodes on the transom bracket and driveshaft
housing. There is one mounted under a cover on the oil panlmidsection.
There are two more mounted under covers on the powerhead, one on each
cylinder head. Like the one used on late model 9.9115 hp motors the cover
bolt is used to secure a clamp, but for the spark plug wires in this case.
These motors use at least one bonding wire as well.
* 25/30 hp (3-cyl) motors -on these motors expect to find one anode in
the form of the trim tab, and at LEAST 2 square anodes mounted to the
bottom of the transom clamp bracket. T-models will also have a small round
anode on the bottom of the transom bracket, right next to one of the square
anodes. Expect to find 2-3 bonding wires on this model as well.
* 40150 hp motors -are pretty much equipped with anodes in the same
way as the 25/30 hp 3-cyl motors. Expect to find one anode in the form of
the trim tab, and at LEAST 2 square anodes mounted to the bottom of the
transom clamp bracket. Expect to find 2-3 bonding wires on this model as
well.
60170 hp motors -normally use one anode in the form of the trim tab,
and a second i~ng ie;:ang~,'ar anode on the bottom of the transom bracket.
In addition, some models (definitely 2003 and later, but possibly some earlier
versions too) use a small round anode mounted just above and to the port
side of the rectangular anode on the transom bracket. Expect to find at least
2 bonding wires on this model, one down at the bottom of the swivel
assembly, but also one toward the top of the tilt assembly.
* 90/115/140 ho motors -There should be a larae rectanaular and
probably small round anode on the bottom of the transom bracket, as well as
a block-shaped anode in a bore at the rear of the gearcase (above the anti-
cavitation plate). In addition, there should be at least 2 anodes mounted
under covers on the side of the powerhead (either on the exhaust cover
under 2-bolt retained oval covers, and1 or on the blocK near the exhaust
cover under the 1 -bolt retained tear-drop shaped covers that Suzuki seems
to favor). Also expect at least 2 bonding wires, one near the lower swivel
point and one near the tilt point.
* 1501175 hp motors -These motors use a bunch of anodes. Expect to
find a rectangular one in a bore in the gearcase, right above the anti-
cavitation plate. Also expect a long rectangular one on the bottom of the
transom bracket, with a small round one mounted slightly above it and to the
port side. There may be at many as 5 on the powerhead under the teardrop
shaped covers that Suzuki favors.
20012251250 hp motors -These motors also use a plethora of anodes.
Expect the common bar shaped one bolted to the bottom of the transom
bracket, as well as a smaller, rectangular one in the bore on the gearcase
just above the anti-cavitation plate. In addition, there should be two more
rectanaular ones bolted to the port side of the midsection. Plus there should
be 6 mounted under 1-bolt teardrop shaped covers on the powerhead, 3 on
the starboard cvlinder bank and 3 on the oort cvlinder bank. Exoect at least
one or more bonding wires at the swivel bracket as well.
* 300 hp motors -It should be no surprise that the largest of the Suzuki
outboards probably has the most anodes. Like the 200-250 hp motors,
expect the common bar shaped one bolted to the bottom of the transom
bracket, as well as a smaller, rectangular one in the bore on the gearcase
just above the anti-cavitation plate. In addition, there should be two more
rectangular ones bolted to the port side of the midsection. One unique anode
is a small round one that is bolted to the face of the gearcase propeller shaft
bearing carrier, normally hidden by the propeller and thrust washer (so be
Fig. 119 Anodes are also usually found on Fig. 121 Jet drive units should have an
the transom bracket like this. . . Fig. 120 ...or like these. . . anode on them as well
Fig. 122 Larger motors are offen equipped
with powerhead anodes mounted under Fig. 123 Most outboards also use bonding Fig. 124 Bonding wires may be mounted
covers (grounding) wires as well alone or along with anodes
sure to check it anytime you service the propeller). Like the other V6 motors,
there should be 6 mounted under 1-bolt teardrop shaped covers on the
powerhead, 3 on the starboard cylinder bank and 3 on the port cylinder
bank. Expect about 4 bonding wires, two at the lower portion of the swivel
bracket, one at the tilt assembly and one between the power trimltilt
assembly and the starboard side bolt for the transom bracket anode.
INSPECTION
+ See Figures 112 thru 124
Visually inspect the anodes, especially gearcase mounted ones, before
and after each use. You'll want to know right away if it has become loose or
fallen off in service (though the silicone that Suzuki usually recommends you
put over their bolt heads should help prevent this. Periodically inspect them
closely to make sure they haven't eroded too much. At a certain point in the
erosion process, the mounting holes start to enlarge, which is when the zinc
might fall off. Obviously, once that happens your engine no longer has any
protection. Generally, a zinc anode is considered worn if it has shrunken to
213 of its original size or less. To help judge this, buy a spare and keep it
handy (in the boat or tow vehicle for comparison).
You can test anode effectiveness using an ohmmeter. In order for
the anode to work it must be in good electrical contact with the motor.
Connect one lead of an ohmmeter to a good ground on the powerhead
and the other to the anode itself. The meter must show little or no
properly. They must be left bare and must be installed onto bare metal of the
motor. If the zincs are installed properly and not painted or waxed, inspect
around them for sings of corrosion. If corrosion is found, strip it off
immediately and repaint with a rust inhibiting paint. If in doubt, replace the
zincs.
Suzuki specifically directs you to apply a small coat of silicone
sealant over the bolt/screw head that secures the anode. Apply only
enough to seal the bolt head to the anode, but don't over apply and
coat the anode, as that would adversely affect the anodes ability to do
its job.
On the other hand, if your zinc seems to erode in no time at all, this may
be a symptom of the zincs themselves. Each manufacturer uses a specific
blend of metals in their zincs. If you are using zincs with the wrong blend of
metals, they may erode more quickly or leave you with diminished protection.
At least annually or whenever an anode has been removed or replaced,
check the mounting for proper electrical contact using a multi-meter. Set the
multi-meter to check resistance (ohms), then connect one meter lead to the
anode and the other to a good, unpainted or corroded ground on the motor.
Resistance should be very low or zero. If resistance is high or infinite, the
anode is insulated and cannot perform its function properly.
SERVICING
See Figures 112 thru 125
resistance, otherwise the anode and mounting surface must be cleaned
of the corrosion, paint or debris that is causing the resistance.
If you use your outboard in salt water or brackish water, and your zincs
never seem to wear, inspect them carefully. Paint, wax or marine growth on
zincs will insulate them and prevent them from performing their function
As noted, depending on your boat, motor and rigging, you may have
anywhere from one to nearly a cool DOZEN anodes. Regardless of !he
number and the location, there are some fundamental rules to follow that will
give your boat and motor's sacrificial anodes the ability to do the best job
protecting your boat's underwater hardware that they can.
NANCE AND TUN
Fig. 125 Suzuki recommends covering the anode retaining bolt
head with Silicone Seal after installation
Some people replace mosVall zincs annually. This may or may not be
necessary, depending on the type of waters in which you boat and
depending on whether or not the boat is hauled with each use or left in for
the season. Either way, it is a good idea inspect zincs at least annually in
order to make sure the mounting surfaces are still clean and free of
corrosion.
The first thing to remember is that zincs are electrical components and
like all electrical components, they require good clean connections. So
anytime they are removed, after you've undone the mounting hardware you
want to get the zinc mounting sites clean and shiny.
Get a piece of coarse emery cloth or some 80-grit sandpaper. Thoroughly
rough up the areas where the zincs attach (there's often a bit of corrosion
residue in these spots). Make sure to remove every trace of corrosion.
Zincs are attached with stainless steel machine screws that thread into
the mounting for the zincs. Over the course of a season, this mounting
hardware is inclined to loosen. Mount the zincs and tighten the mounting
hardware securely. Tap the zincs with a hammer hitting the mounting screws
squarely. This process tightens the zincs and allows the mounting hardware
to become a bit loose in the process. Now, do the final tightening. This will
insure your zincs stay put for the entire season.
H Suzuki specifically directs you to apply a small coat of silicone
sealant over the bolUscrew head that secures the anode. Apply only
enough to sealant the bolt head to the anode, but don't over apply and
coat the anode, as that would adversely affect the anodes ability to do
its job.
Many of the larger Suzuki motors use anodes mounted to the powerhead
under small covers. The cover most often used by Suzuki is a tear-drop
shaped cover that is secured by one bolt. At LEAST on the covers used for
150 hp and larger motors (but possibly on smaller ones as well) these covers
can use a 10mm bolt as a screw-jack to push them off their mounting when
stuck. Simply remove the usual mounting bolt and install a 10mm bolt, gently
turning it inward to push the cover off the powerhead.
When servicing bonding wires, pay close attention to any rusUcorrosion
and be sure to remove, clean and replace the wires or bolts if any is found.
Also pay close attention to any washers which may b e used. In the case of
some models an insulating washer may be placed under the bonding wire
terminal (between the terminal and the motor body). If used, this insulating
washer must be placed in the same position during installation.
INSPECTON
See Figure 126
Timing belts are only used on the 9.9115 hp and 60170 hp motors covered
here. Of the motors not mentioned, the smallest instead utilize a gear driven
camshaft, while the rest of the motors 25 hp (3-cyl) and larger that weren't
mentioned utilize a timing chain. One advantage of the gear or chain set-ups
is that they are maintenance free and are generally considered lifetime
components. Then again, should a gear or chain fail, service is MUCH more
involved.
The one great advantage of the timing BELT is that it can be inspected or
replaced with a relatively simple procedure, compared to the gear or chain
assembly (some of which are mounted on the bottom of the powerhead)
which requires at least a partial disassembly of the powerhead. Should a
timing chain stretch to the point where the automatic tensioner cannot
compensate you will usually hear an audible tapping and/or notice
timinglperformance problems which would lead you to diagnose the problem
further.
That said, the timing belt is in fact a long life component that does not
require much in the way or service, but we would recommend that you
inspect it at least once every year. Also, the manufacturer provides a
recommended replacement interval of about every 4 years or 800 hours of
operation, whichever comes first. Keep in mind, a timing belt that breaks or
even slips a tooth will likely disable the motor, possibly stranding the boat.
More importantly, the 60170 hp 4-strokes are INTERFERENCE motors,
meaning that a severely slipped or a broken belt could cause SEVERE
engine damage. Don't play with fire.
The camshaftlflywheel cover must be removed for access to inspect the
timing belt.
1. For safety when working around the flywheel, disconnect the
negative battery cable and/or disconnect the leads from the spark plugs,
then ground the leads on the powerhead.
H Although not absolutely necessary for this procedure, it is a good
idea to remove the spark plugs at this time. Removing the spark plugs
will relieve engine compression, making it easier to manually rotate the
motor. Also, it presents a good opportunity to inspect, clean andlor
replace the plugs.
2. Remove the manual starter assembly or the flywheel cover, as
applicable, for better access to the timing belt.
3. Use low-pressure compressed air to blow debris out from under the
camshaft pulley, flywheel and timing belt.
4. Visually check the belt for worn, cracked or oil soaked surfaces.
Slowly rotate the flywheel (by hand) while inspecting all of the timing belt
cogs.
5. Visually check the camshaft pulley and flywheel teeth for worn,
cracked, chipped or otherwise damaged surfaces.
6. If the belt and or pulleys are damaged, replace them as described
under Powerhead in this manual.
7. If removed, install the manual starter assembly or flywheel cover to
the powerhead.
8. Install the spark plugs, then connect the leads followed by the
negative battery cable and the engine cover.
Fig. 126 You'll have to remove the camshaft/flywheel cover to
inspect the timing belt
NANCE AND TUNE-UP
+ See Figures 127 and 128
Batteries require periodic servicing, so a definite maintenance program
will help ensure extended life.
Afailure to maintain the battery in good order can prevent it from properly
charging or properly performing its job even when fully charged. Low levels
of electrolyte in the cells (if a wet cell battery is used), loose or dirty cable
connections at the battery terminals or possibly an excessively dirty battery
top can all contribute to an improperly functioning battery. So battery
maintenance, first and foremost, involves keeping the battery full of
electrolyte, properly charged and keeping the casing/connections clean of
corrosion or debris.
If a battery charges and tests satisfactorily but still fails to perform
properly in service, one of three problems could be the cause.
1. An accessory left on overnight or for a long period of time can
discharge a battery.
The Engine Control Unit (ECU) on fuel-injected motors will continue
to draw a small amount of current from the battery, even when the
motor is shut off. Although it will takes weeks to discharge a fully
charged battery, periodically recharging the battery, or isolating it by
disconnecting the cables or shutting off the battery switch when the
boat is dockside or on the trailer will prevent this.
2. Using more electrical power than the stator assembly or lighting coil
can replace would slowly drain the battery during motor operation, resulting
in an undercharged condition.
3. A defect in the charging system. A faulty stator assembly or lighting
coil, defective regulator or rectifier or high resistance somewhere in the
system could cause the battery to become undercharged.
MAINTENANCE
See Figures 128 thru 132
Electrolyte Level
The most common and important procedure in wet cell battery
maintenance is checking the electrolyte level. On serviceable batteries, this
is accomplished by removing the cell caps and visually observing the level in
the cells. The bottom of each cell has a split vent which will cause the
surface of the electrolyte to appear distorted when it makes contact. When
the distortion first appears at the bottom of the split vent, the electrolyte level
is correct. Smaller marine batteries are sometimes equipped with translucent
cases that are printed or embossed with high and low level markings on the
side. On some of these, shining a flashlight through the battery case will help
make it easier to determine the electrolyte level.
During hot weather and periods of heavy use, the electrolyte level should
be checked more often than during normal operation. Add distilled water to
bring the level of electrolyte in each cell to the proper level. Take care not to
overfill, because adding an excessive amount of water will cause loss of
electrolyte and any loss will result in poor performance, short battery life and
will contribute quickly to corrosion.
Never add electrolyte from another battery. Use only distilled water.
Even tap water may contain minerals or additives that will promote
corrosion on the battery plates, so distilled water is always the best
solution.
Although less common in marine applications than other uses today (but
becoming more popular every year) some sealed maintenance-free batteries
may also require electrolyte level checks. When so equipped, you can check
Fig. 127 Explosive hydrogen gas is released
from the batteries in a discharged state.
This one exploded when something ignited
the gas. Explosions can also be caused by a
spark from the battery terminals or jumper Fig. 128 Ignoring a battery (and corrosion)
Fig. 129 The first step in battery
maintenance is to make sure the terminals
cables to this extent is asking for it to fail are clean and tight
Fig. 130 If cleaning is necessary, place a
battery terminal tool over posts, then rotate
back and forth. ..
Fig. 131 ...until the internal brushes
expose a fresh, clean surface on the post
Fig. 132 Clean the insides of cable ring
terminals using the tool's wire brush
the level through the window built into the tops of the cases. The problem for
marine applications is the tendency for deep cycle use to cause electrolyte
evaporation and electrolyte cannot be replenished in a sealed battery.
The second most important procedure in battery maintenance (and this is
necessary for ALL batteries whether wet cell or drylgel cell) is periodically
cleaning the battery terminals and case.
Cleaning
Dirt and corrosion should be cleaned from the battery as soon as it is
discovered. Any accumulation of acid film or dirt will permit a small amount of
current to flow between the terminals. Such a current flow will drain the
battery over a period of time.
Clean the exterior of the battery with a solution of diluted ammonia or a
paste made from baking soda and water. This is a base solution to neutralize
any acid that may be present. Flush the cleaning solution off with plenty of
clean water.
Take care to prevent any of the neutralizing solution from entering
the cells as it will quickly neutralize the electrolyte (ruining the battery).
Poor contact at the terminals will add resistance to the charging circuit.
This resistance will cause the voltage regulator to register a fully charged
battery and thus cut down on the stator assembly or lighting coil output
adding to the low battery charge problem.
At least once a season, thebattery terminals and cable clamps should be
cleaned. Loosen the clamos and remove the cables, neaative cable first. On
batteries with top mounted posts, if the terminals ap'pearstuck, use a puller
specially made for this purpose to ensure the battery casing is not damaged.
NEVER pry a terminal off a battery post. These are inexpensive and
available in most parts stores.
Clean the cable clamps and the battery terminal with a wire brush until all
corrosion, grease, etc., is removed and the metal is shiny. It is especially
important to clean the inside of the clamp thoroughly (a wire brush or brush
part of a battery post cleaning tool is useful here), since a small deposit of
foreign material or oxidation there will prevent a sound electrical connection
and inhibit either starting or charging. It is also a good idea to apply some
dielectric grease to the terminal, as this will aid in the prevention of
corrosion.
Suzuki usually suggests that you can coat the terminals using Water
Resistant Grease marine grease to prevent corrosion.
After the clamps and terminals are clean, reinstall the cables, negative
cable last, do not hammer the clamps onto battery posts. Tighten the clamps
securely but do not distort them. To help slow or prevent corrosion, give the
clamps and terminals a thin external coating of grease after installation.
Check the cables at the same time that the terminals are cleaned. If the
insulation is cracked or broken or if its end is frayed, that cable should be
replaced with a new one of the same length and gauge.
TESTING
DERATE
A quick check of the battery is to place a voltmeter across the terminals.
Although this is by no means a clear indication, it gives you a starting point
when trying to troubleshoot an electrical problem that could be battery
related. Most marine batteries will be of the 12 volt DC variety. They are
constructed of 6 cells, each of which is capable of producing slightly more
man two volts, wired in series so that total voltage is 12 volts and a fraction.
A fully charged battery will normally show more than 12 and generally slightly
less than 13 volts across its terminals. But keep in mind that just because a
battery reads 12.6 or 12.7 volts does NOT mean it is fully charged. It is
possible for it to have only a surface charge with very little amperage behind
it to maintain that voltage rating for long under load.
Now conversely, a discharged (or damaged) battery will read some value
less than 12 volts, but can (unless damaged) it be brought back to 12 volts
through recharging. Of course a battery with one or more shorted or un-
chargeable cells will also read less than 12, but it cannot be brought back to
12+ volts after charging. For this reason, the best methoddo check wet cell
battery condition on most marine batteries is through a specific gravity
check.
& Sealed wet cell batteries or dry celllgel cell batteries obviously
cannot be tested using the electrolyte. Instead they must be charged
and then their output (in voltage and amperage) is measured using a
carbon pile load tester and voltmeterlammeter.
A hydrometer is a device that measures the density of a liquid when
compared to water (specific gravity). Hydrometers are used to test batteries
by measuring the percentage of sulfuric acid in the battery electrolyte in
terms of specific gravity. When the condition of the battery drops from fully
charged to discharged, the acid is converted to water as electrons leave the
solution and enter the plates, causing the specific gravity of the electrolyte to
drop.
It may not be common knowledge but hydrometer floats are calibrated for
use at SOT (27%). If the hydrometer is used at any other temperature,
hotter or colder, a correction factor must be applied.
emember, a liquid will expand if it is heated and will contract if
cooled. Such expansion and contraction will cause a definite change in
the specific gravity of the liquid, in this case the electrolyte.
A quality hydrometer will have a therrnometerltemperaturecorrection table
in the lower portion, as illustrated in the accompanying illustration. By
measuring the air temperature around the battery and from the table, a
correction factor may be applied to the specific gravity reading of the
hydrometer float. In this manner, an accurate determination may be made as
to the condition of the battery.
When using a hydrometer, pay careful attention to the following points:
1. Never attempt to take a reading immediately after adding water to the
battery. Allow at least 114 hour (15 min.) of charging at a high rate to
thoroughly mix the electrolyte with the new water. This time will also allow for
the necessary gases to be created.
2. Always be sure the hydrometer is clean inside and out as a
precaution against contaminating the electrolyte.
3. If a thermometer is an integral part of the hydrometer, draw liquid into
it several times to ensure the correct temperature before taking a reading.
4 Be sure to hold the hydrometer vertically and suck up liquid only until
the float is free and floating.
5. Always hold the hydrometer at eye level and take the reading at the
surface of the liquid with the float free and floating.
6. Disregard the slight curvature appearing where the liquid rises
against the float stem. This phenomenon is due to surface tension.
7. Do not drop any of the battery fluid on the boat or on your clothing,
because it is extremely caustic. Use water and baking soda to neutralize any
battery liquid that does accidentally drop.
8. After drawing electrolyte from the battery cell until the float is barely
free, note the level of the liquid inside the hydrometer. If the level is within
the charged (usually green) band range for all cells, the condition of the
battery is satisfactory. If the level is within the discharged (usually white)
band for all cells, the battery is in fair condition.
9. If the level is within the green or white band for all cells except one,
which registers in the red, the cell is shorted internally. No amount of
charging will bring the battery back to satisfactory condition.
10. If the level in all cells is about the same, even if it falls in the red
band, the battery may be recharged and returned to service. If the level fails
to rise above the red band after charging, the only solution is to replace the
battery.
STORAGE
See Figure 135
If the boat is to be laid up (placed into storage) for the winter or for more
than a few weeks, special attention must be given to the battery to prevent
complete discharge andlor possible damage to the terminals and wiring.
Before putting the boat in storage, disconnect and remove the batteries.
Clean them thoroughly of any dirt or corrosion and then charge them to full
specific gravity readings. After they are fully charged, store them in a clean
cool dry place where they will not be damaged or knocked over, preferably
on a couple blocks of wood if it is a non-sealed wet cell battery. Storing a
non-sealed wet cell battery up off the deck, will permit air to circulate freely
around and under the battery and will help to prevent condensation.
Never store the battery with anything on top of it or cover the battery in
such a manner as to prevent air from circulating around the filler caps. All
non-sealed batteries, both new and old, will discharge during periods of
storage, more so if they are hot than if they remain cool. Therefore, the
electrolyte level and the specific gravity should be checked at regular
intervals. A drop in the specific gravity reading is cause to charge them back
to a full reading.
In cold climates, care should be exercised in selecting the battery storage
area. A fully-charged battery will freeze at about 60¡ below zero. The
Fig. 133 On non-sealed batteries you can Fig. 134 . ..to check battery Fig. 135 When in storage, periodically
use a hydrometer. .. chargelcondition charge a battery for maximum life
I I
electrolyte of a discharged battery, almost dead, will begin forming ice at
about 1YF above zero.
For more information on batteries and the engine electrical systems,
please refer to the Ignition and Electrical section of this manual.
INSPECTION AND CARE
SY
+ See Figures 136,137 and 138
Fiberglass reinforced plastic hulls are tough, durable and highly resistant
to impact. However, like any other material they can be damaged. One of the
advantages of this type of construction is the relative ease with which it may
be repaired.
A fiberglass hull has almost no internal stresses. Therefore, when the hull
is broken or stove-in, it retains its true form. It will not dent to take an out-of-
shape set. When the hull sustains a severe blow, the impact will be either
absorbed by deflection of the laminated panel or the blow will result in a
definite, localized break. In addition to hull damage, bulkheads, stringers and
other stiffening structures attached to the hull may also be affected and
therefore, should be checked. Repairs are usually confined to the general
area of the rupture.
The best way to care for a fiberglass hull is to wash it thoroughly,
immediately after hauling the boat while the hull is still wet.
A foul bottom can seriously affect boat performance. This is one reason
why racers, large and small, both powerboat and sail, are constantly giving
attention to the condition of the hull below the waterline.
In areas where marine growth is prevalent, a coating of vinyl, anti-fouling
bottom paint should be applied if the boat is going to be left in the water for
extended periods of time such as all or a large part of the season. If growth
has developed on the bottom, it can be removed with a diluted solution of
muriatic acid applied with a brush or swab and then rinsed with clear water.
Always use rubber gloves when working with Muriatic acid and take extra
care to keep it away from your face and hands. The fumes are toxic.
Therefore, work in a well-ventilated area or if outside, keep your face on the
windward side of the work.
if marine growth is not too severe you mav avoid the
unpleasantness of working with muriatic acid by trying a power washer
instead. Most marine vegetation can be removed by pressurized water
and a little bit of scrubbing using a rough sponge (don't use anything
that will scratch or damage the surface).
Barnacles have a nasty habit of making their home on the bottom of boats
that have not been treated with anti-fouling paint. Actually they will not harm
the fiberglass hull but can develop into a major nuisance.
If barnacles or other crustaceans have attached themselves to the hull,
extra work will be required to bring the bottom back to a satisfactory
condition. First, if practical, put the boat into a body of fresh water and allow
it to remain for a few days. A large percentage of the growth can be removed
in this manner. If this remedy is not possible, wash the bottom thoroughly
with a high-pressure fresh water source and use a scraper. Small particles of
hard shell may still hold fast. These can be removed with sandpaper.
Fig. 136 The best way to care for a Fig. 137 ...as a clean and shiny hull makes Fig. 138 If marine growth is a problem,
fiberglass hull is to wash it thoroughly.. . for a happy boat apply a coating of anti-foul bottom paint
A proper tune-up is the key to long and trouble-free outboard life and the
work can yield its own rewards. Studies have shown that a properly tuned
and maintained outboard can achieve better fuel economy than an out-of-
tune engine. As a conscientious boater, set aside a Saturday morning, say
once a month, to check or replace items which could cause major problems
later. Keep your own personal log to jot down which services you performed,
how much the parts cost you, the date and the number of hours on the
engine at the time. Keep all receipts for such items as oil and filters, so that
they may be referred to in case of related problems or to determine
operating expenses. These receipts are the only proof you have that the
required maintenance was performed. In the event of a warranty problem on
newer engines, these receipts will be invaluable.
The efficiency, reliability, fuel economy and enjoyment available from
boating are all directly dependent on having your outboard tuned properly.
The importance of oerformina service work in the orouer seauence cannot
be over emphasized. ~eforehakin~
any adjustments, check the
specifications. Never rely on memory when making critical adjustments.
Before tuning any outboard, insure it has satisfactory compression. An
outboard with worn or broken piston rings, burned pistons or scored cylinder
walls, will not perform properly no matter how much time and expense is
spent on the tune-up. Poor compression must be corrected or the tune-up
will not give the desired results.
The extent of the engine tune-up is usually dependent on the time lapse
since the last service. In this section, a logical sequence of tune-up steps will
be presented in general terms. If additional information or detailed service
work is required, refer to the section of this manual containing the
appropriate instructions.
A tune-up can be defined as pre-determined series of procedures
(adjustments, tests and worn component replacements) that are performed
to bring the engine operating parameters back to original condition. The
series of steps are important, as the later procedures (especially
adjustments) are dependant upon the earlier procedures. In other words, a
procedure is performed only when subsequent steps would not change the
result of that procedure (this is mostly for adjustments or settings that would
be incorrect after changing another part or setting). For instance, fouled or
excessively worn spark plugs may affect engine idle. If adjustments were
made to the idle speed or mixture before these plugs were cleaned or
replaced, the idle speed or mixture might be wrong after replacing the plugs.
The possibilities of such an effect become much greater when dealing with
multiple adjustments such as timing, idle speed and/or idle mixture.
Therefore, be sure to follow each of the steps given here. Since many of the
steps listed here are full procedures in themselves, refer to the procedures of
the same name in this section for details.
B Now the truth of the matter is that many of these motors are
equipped with sophisticated electronic engine controls, and as a result
there are FEW adjustments that are necessary or that affect one
another, but it's still a good idea to pay attention to items and handle
them in the proper sequence, especially if there are any
synchronization steps for linkage. And even many of the carbureted
motors have more electronic controls on them (like electronic ignitions)
than outboards of days gone by. But still, this does not negate the need
for following a proper sequence when making checks or any applicable
adjustments.
A complete pre-season tune-up should be performed at the beginning of
each season or when the motor is removed from storage. Operating
conditions, amount of use and the frequency of maintenance required by
your motor may make one or more additional tune-ups necessary during the
season. Perform additional tune-ups as use dictates.
1. Before starting, inspect the motor thoroughly for signs of obvious
leaks, damage and loose or missing components. Make repairs, as
necessary.
2. On all models, check and adjust the valve lash clearance (actually
recommendations for this are every 200 hours or annually, whichever comes
first).
On all motors, but especially the 40-70 hp models, we suggest that
you pay close attention to the valve clearance checks. Use It as an
opportunity to check for premature camshaft wear (some of which was
noticed in the field on some early versions of these motors). This wear
often occurs from the use of incorrect typeslgrade of oil or from
Infrequent oil changes. A sudden or drastic change in valve lash can be
an early indicator, giving you time to change types of oil or the
frequency of service the engine is receiving before necessitating a
costly and troublesome camshaft replacement.
3. Perform a compression check to make sure the motor is
mechanically ready for a tune-up. An engine with low compression on one or
more cylinders should be overhauled, not tuned. A tune-up will not be
successful without sufficient engine compression. Refer to the Compression
Test in this section.
4. Since the spark plugs must be removed for the compression check,
take the opportunity to inspect them thoroughly for signs of oil fouling, carbon
fouling, damage due to detonation, etc. Clean and re-gap the plugs or, better
yet, install new plugs as no amount of cleaning will precisely match the
performance and life of new plugs. Refer to Spark Plugs, in this section.
5. Visually inspect all ignition system components for signs of obvious
defects. Look for signs of burnt, cracked or broken insulation. Replace wires
or components with obvious defects. If spark plug condition suggests weak
or no spark on one or more cylinders, perform ignition system testing to
eliminate possible worn or defective components. Refer to the Ignition
System Inspection procedures in this section and the Ignition and Electrical
System section.
6. Remove and clean (on serviceable filters) or replace the inline filter
and/or fuel pump filter, as equipped. Refer to the Fuel Filter procedures in
this section. Perform a thorough inspection of the fuel system, hoses and
components. Replace any cracked or deteriorating hoses.
7. Perform engine Timing and Synchronization adjustments as
described in this section.
E Only some of the motors covered by this manual allow for any
ignition timing or carburetor adjustment procedures and even then
none of them require the level of tuning attention that was once the
norm. All of the motors are equipped with electronic ignition systems
that limit or completely eliminate timing adjustments (though you can
usually still perform a timing check to see if the system is operating
properly). All of the carburetors covered here are U.S. EPA or EU
regulated when sold in those respective markets and contain few
mixture adiustments. EFI motors are all but comnletelv controlled bv
the ~ngine~ontrol
Unit (ECU) and normally contain no timing or fuel
adjustments.
8. Remove the propeller in order to thoroughly check for leaks at the
shaft seal. Inspect the propeller condition, look for nicks, cracks or other
signs of damage and repair or replace, as necessary. If available from the
manufacturer, install a test wheel'to run the motor in a test tank after
com~letion of the tune-UD. If no test wheel is available, lubricate the
shafkplines, then install the propeller. Refer to the procedures for Propeller
in this section.
9. Change the gearcase oil as directed under the Gearcase Oil
procedures in this section. If you are conducting a pre-season tune-up and
the oil was changed immediately prior to storage this is not necessary. But,
be sure to check the oil level and condition. Drain the oil anyway if significant
contamination is present.
B Anytime large amounts of water or debris is present in the gearcase
oil, be sure to troubleshoot and repair the problem before returning the
gearcase to service. The presence of water may indicate problems with
the seals, while debris could a sign that overhaul is required.
10. Check all accessible bolts and fasteners and tighten any that are
loose.
11. Pressurize the fuel system according to the procedures found in the
Fuel System section, then check carefully for leaks.
12. Perform a test run of the engine to verify proper operation of the
starting, fuel, oil and cooling systems. Although this can be performed using
a flushltest adapter or even on the boat itself (if operating with a normal
loadlpassengers), the preferred method is the use of a test tank. If possible,
run the engine, in a test tank using the appropriate test wheel. Monitor the
cooling system indicator stream to ensure the water pump is working
properly. Once the engine is fully warmed, slowly advance the engine to
wide-open throttle, then note and record the maximum engine speed. Refer
to the Tune-up Specifications chart to compare engine speeds with the test
propeller minimum rpm specifications and/or the WOT Max RPM limits. If
engine speeds are below minimum test specifications or too far below the
MAX RPM limits, yet engine compression was sufficient at the beginning of
this procedure, recheck the fuel and ignition system adjustments.
The quickest (but not necessarily most accurate) way to gauge the
condition of an internal combustion engine is through a compression check.
In order for an internal combustion engine to work properly, it must be able to
generate sufficient compression in the combustion chamber to take
advantage of the explosive force generated by the expanding gases after
ignition. This is true on all motors whether they are of the 2- or 4-stroke
design.
If the combustion chambers, valves or gasket mating surfaces like
cylinder heads or compression rings are worn or damaged in some fashion
as to allow pressure to escape, the engine cannot develop sufficient
horsepower. Under these circumstances, combustion will not occur properly,
airlfuel mixtures cannot be set to maximize power and minimize emissions. A
engine with poor compression on one or more cylinders cannot given a
proper tune-up, it should be overhauled.
There are two compression tests provided here, the first (TUNE-UP
COMPRESSION TEST) is a quick-test used during a tune-up to determine if
you should continue or stop and overhaul the motor. This test is what
technicians think of when you say compression check as it measures the
ability of a motor to create compression. The second (OVERHAUL
LEAKAGE TEST) is a diagnostic check that is used when an engine is
suspect (has already failed part of a Tune-up Compression Test) or during
assembly after an overhaul (to confirm powerhead condition). The second
test is also referred to as a "leak-down" test by some technicians as it
measures the ability of an engine to hold pressure provided by another
source and keep it from "leaking."
A compression check requires a compression gauge and a spark plug
port adapter that matches the plug threads of your motor. A leakage test
requires a source of pressurized air, a pressure gauge or leak-down test
adapter, a spark plug port adapter and an air source (such as a portable air
tank filled with pressurized air or best yet, an air compressor).
TUNE-UP COMPRESSION CHECK
ERATE
See Figure 139
When analyzing the results of a compression check, generally the actual
amount of pressure measured during a compression check is not as
important as the variation from cylinder-to-cylinder or from test-to-test on the
same motor. For multi-cylinder powerheads, a variation of 14 psi (100 kPa)
or more is usually considered questionable on these motors (though there is
one exception, the 60/70 hp motors are allowed a variation as high as 28 psi
(200 kPa). On single cylinder powerheads, a drop of about 14 psi (100 kPa)
from the normal compression pressure you established when it was new (or
at least from the last test) is cause for concern (you did do a compression
test on it when it was new, didn't you?).
Ok, for the point of arguments sake let's say you bought the engine used
or never checked compression the first season or so, assuming it wasn't
something you needed to worry about. You're not alone. LUCKILY, unlike
many manufacturers, Suzuki publishes a technical specification for the
amount of compression MOST of their engines should generate. Whenever a
specification was available we've put them as the first entry in the Engine
Specifications charts found at the end of the Powerhead section. When
working on these outboards, be sure to check the chart for the appropriate
powerhead to help interpret the test results. But keep in mind that most of
these specifications should be consider guidelines and not absolutes. Motors
may run fine when outside these parameters, it is just the further from
specification, the less likely this would be.
When taking readings during the compression check, repeat the
procedure a few times for each cylinder, recording the highest reading for
that cylinder. Then, for all multi-cylinder motors covered by this manual, the
compression reading on the lowest cylinder should within 14 psi (100 kPa) or
28 psi (200 kPa), depending on the model, of the highest reading. If not,
consider performing an OVERHAUL LEAKAGE CHECK to determine if the
powerhead is in need of a complete or partial overhaul.
1 Fig. 139 Compression check on a typical multi-cylinder powerhead 1
If the powerhead has been in storage for an extended period, the
piston rinas mav have relaxed. This will often lead to initiallv low and
misleading readings. Always run an engine to normal operating
temperature to ensure that the readings are accurate.
1. If necessary, remove the lower engine cowling for access to the
lower spark plug(s). For details, please refer to Engine Covers (Top and
Lower Cases), earlier in this section.
2. On 300 hp motors, remove the bolts and disconnect the port and
starboard air duct guards for access.
B If you've never removed the spark plugs from this cylinder head
before, break each one loose and retighten them, to make sure they will
not seize in the head once it is warmed. Better yet, remove each one
and coat the threads very lightly with some fresh anti-seize compound.
3. Using a test tank, flush fitting adapter or other water supply, start and
run the engine until it reaches normal operating temperature, then shut the
engine off.
4. Since compression testing uses a gauge threaded into the spark plug
ports you need to remove the spark plugs and disable the ignition system.
There are various methods to disable the ignition. On all but direct ignition
models, removing the lanyard clip should be sufficient to prevent spark. On
direct ignition models (meaning 40150, or 150-300 hp models where the
ignition coils are mounted directly on top of the spark plugs), tag and
disconnect the wiring, then remove the ignition coils themselves. On these
same Dl models, Suzuki also directs you to tag and disconnect all of the fuel
injector connectors.
Removing all the spark plugs and cranking over the powerhead can
lead to an explosion if raw fuelloil sprays out of the plug holes. A plug
wire could spark and ignite this mix outside of the combustion
chamber if the system isn't disabled. So check and make sure no spark
is being produced. IF IT IS, then ground the spark plug [email protected]) to the
motor.
5. Remove all the spark pluqs and be sure to keep them in order (as a
reference to cylinder condition). Carefully inspect the looking forany
inconsistencv in coloration and for anv sian of water or rust near the tin
Refer to the procedures on Spark plugs 6this section for more details.
6. Thread the compression gauge into the No. 1 spark-plug hole, taking
care to not cross-thread the fitting.
Some engines allow only minimal opening if the gearshift is in
neutral, to guard against over-revving.
7. Open the throttle to the wide open throttle position and hold it there.
With most motors you can just move the throttle linkage by hand, andlor
using the remote or tiller controls (hint, when using the remote controls if
there is a neutral button on the shifter, use it so that you are not trying to
crank the motor in gear, which usually won't work).
For all of their mechanically controlled, remote motors Suzuki
recommends disconnecting the throttle cable and manually holding the
throttle open by hand. We don't think this is always necessary (see
previous step about using neutral button when available) HOWEVER, if
you don't get sufficient readings using the previous step's methods,
then go ahead, disconnect the cable and hold the throttle open by
hand.
8. On 300 hp models, the unique throttle-by-wire remote controls
require an additional step before cranking the motor. On these models, turn
the main switch ON and wait for the LED lights to activate, then depress the
"THROTTLE ONLY button and move the remote control lever on the throttle
to the wide open (full throttle) position. Then, in the next step of this
procedure, use the Start & Stop button to crank the motor.
9. On 2003 or later 60170 hp motors, Suzuki recommends disconnect
the high pressure fuel pump lead wire and properly relieving fuel system
pressure (as detailed in the Fuel System section) before proceeding.
10. Crank over the engine an equal number of times for each cylinder
you test, zeroing the gauge for each cylinder.
11. If you have electric start, count the number of seconds you crank. On
manual start, pull the starter rope four to five times for each cylinder you are
testing.
12. Record your readings from each cylinder. When all cylinders are
tested, compare the readings to specifications listed in the Engine
Specification chart for that powerhead and to the comparative criterion, as
applicable.
13. If compression readings are lower than normal for any cylinders, try a
"wet" compression test, which can temporarily seal piston rings bringing the
pressure up and helping to determine if they are the cause of the low
reading. Using a can of fogging oil, fog the cylinder with a circular motion to
distribute oil spray all around the perimeter of the piston. Retest the cylinder:
a. If the compression rises noticeably in a wet test, either the piston
rings are sticking (you MAY be able to cure the problem by decarboning the
powerhead using an appropriate decarboning engine treatment) or the
cylinder is scored/worn but the oil temporarily sealed the rings enough for the
test.
b. H the dry compression test was really low and no change is evident
during the wet test, the cylinder is dead. Then either the piston and/or
cylinder are worn beyond specification or there is a problem with the valve
train. A valve that is sticking open (due to wear, physical damage, warpage
or improper adjustment) will allow pressure to escape, lowering the
compression readings.
14. If two adjacent cylinders on a multi-cylinder engine give a similarly
low reading then the problem may be a faulty head gasket. This should be
suspected if there was evidence of water or rust on the spark plugs from
these cylinders.
OVERHAUL LEAKAGE CHECK
DERATE
The 4-stroke engine acts as a pump, drawing airlfuel mixture into the
combustion chambers. Vacuum is created in the combustion chamber itself
as the piston moves downward on the intake stroke, drawing the airtfuel
mixture through the intake manifold and intake valve($. Similarly, the
pressure created on the exhaust stroke forces unburned gases out through
the exhaust valves. Like 2-strokes, air leaks can wreak havoc for these
motors, but in a slightly different way.
On carbureted 4-stroke motors, a lean fuel mixture can result from leaks
downstream of the carburetorlthrottle body (leaks between the carburetor
and intake manifold or between the intake manifold and engine). Air leaks
can also occur, as valve trains play an important part in cylinder
pressurization (a damaged or improperly adjusted intakelexhaust valve or
improper valve timing can cause problems).
If the powerhead is running, soapy water can be sprayed onto the
suspected sealing areas. If bubbles develop, there is a leak at that point. Oil
around sealing points and on ignition parts under the flywheel indicates a
crankcase leak.
The base of the powerhead and lower crankshaft seal is impossible to
check on an installed powerhead. When every test and system have been
checked out and the bottom cylinder seems to be effecting performance,
then the lower seal should be tested.
The key to a leakage (leak down) test is to manually pressurize a cylinder
when the piston is at or near TDC and all the valves are already closed. This
is done through a source of compressed air, a hose and a fitting that threads
into the spark plug adaptor. The idea is to watch and make sure a certain
amount of pressure can be built up in the cylinder and that no more than a
small amount of leakage will occur under a short amount of time. Should
leakage occur, you simply have to listenlfeel for it (at the intake manifold, at
exhaust ports or under the exhaust cover, or at the oil pan/crankcase/oil fill,
to determine the source of the leak -intake valve, exhaust valve or
pistontrings respectively).
1. Prepare a cylinder for testing by turning the engine (in the normal
direction of rotation, remember the largest motors covered here, specifically
90-300 hp motors, use counter-rotating powerheads, meaning powerheads
that turn COUNTERCLOCKWISE) until that piston is approaching top dead
center of the compression stroke. This can be determined by removing the
valve cover and observing the intakelexhaust valves. Both valves will close
and remain so as the engine approaches the top of the compression stroke.
If one valve (the exhaust valve) opens as this occurs, the engine is on the
exhaust stroke and crankcase must be rotated one complete revolution to
bring that cylinder onto the compression stroke. When this happens you can
watch the valves, the intake will open and then close and as it closes the
piston is approaching TDC.
Top dead center of the compression stroke is the point at which all
valves should be closed so the airlfuel mixture will be properly
compressed and the power from combustion can be fully utilized.
Leakage tests can only be conducted once the valves are fully seated.
2. Using a suitable regulated air source, pressurize the combustion
chamber to about 100 psi (690 kPa), or as directed by the instructions that
come with the leak-down tester.
3. Watch the gauges on the tester and, if necessary, listen for leakage
at the carburetortthrottle bodv andtor exhaust (which would indicate valve
sealing problems) or at the engine crankcase oil fill (which would indicate
problems with the cylinder wallslcompression rings). Only a very small
amount of pressure should leak under normal conditions (again, refer to any
directions that come with the leak-down tester), excessive pressure leakage
indicates a need for overhaul or repair. Repeat the procedure for each
remaining cylinder on the motor.
W The manufacturer does not provide specifications for leak-down
tests. Industry standards vary greatly from manufacturer-to-
manufacturer. Expect a small percentage of leakdown to be normal,
anvthina from a few percent to 10 percent should not be cause for
alarm. Conversely, twenty percent ieakdown on a 4-stroke motor is
generally considered a reason for overhaul when combined with other
driveability symptoms.
4. Note the leaking areas and repair or replace components, seals or
gaskets, as applicable.
The spark plug performs four main functions:
5 First and foremost, it provides spark for the combustion process to
occur.
0
It also removes heat from the combustion chamber.
Its removal provides access to the combustion chamber (for inspection
or testing) through a hole in the cylinder head.
It acts as a dielectric insulator for the ignition system.
It is important to remember that spark plugs do not create heat, they help
remove it. Anything that prevents a spark plug from removing the proper
amount of heat can lead to pre-ignition, detonation, premature spark plug
failure and even internal engine damage.
In the simplest of terms, the spark plug acts as the thermometer of the
engine. Much like a doctor examining a patient, this "thermometer" can be
used to effectively diagnose the amount of heat present in each combustion
chamber.
Spark plugs are valuable tuning tools, when interpreted correctly. They will
show symptoms of other problems and can reveal a great deal about the
engine's overall condition. Evaluating the appearance of the spark plug's
firing tip, gives visual cues to determine the engine's overall operating
condition, get a feel for airlfuel ratios and even diagnose driveability
problems.
As spark plugs grow older, they lose their sharp edges and material from
the center and ground electrodes slowly erodes away. As the gap between
these two points grows, the voltage required to bridge this gap increases
proportionately. The ignition system must work harder to compensate for this
higher voltage requirement and hence there is a greater rate of misfires or
incomplete combustion cycles. Each misfire means lost horsepower, reduced
fuel economy and higher emissions. Replacing worn out spark plugs with
new ones (with sharp new edges) effectively restores the ignition system's
efficiency and reduces the percentage of misfires, restoring power, economy
and reducing emissions.
Although spark plugs can typically be cleaned and re-gapped if they
are not excessively worn, no amount of cleaning or re-gapping will
return most spark plugs to original condition and it is usually best to
just go ahead and replace them.
How long spark plugs last will depend on a variety of factors, including
engine compression, fuel used, gap, centerlground electrode material and
the conditions in which the outboard is operated.
SPARK PLUG HEAT RANGE
See Figure 140
Spark plug heat range is a measurement of its ability to dissipate heat
from the combustion chamber. The longer the insulator (or the farther the
path the heat must travel from the plug tip to the cylinder head), the hotter
the plug will operate; the shorter the insulator (the shorter the path from
electrode to the cylinder head) the cooler it will operate.
Selecting a spark plug with the proper heat range will ensure that the tip
maintains a temperature high enough to prevent fouling, yet cool enough to
prevent pre-ignition. A plug that absorbs little heat and remains too cool will
quickly accumulate deposits of oil and carbon since it won't be able to burn
them off. This leads to plug fouling and consequently to misfiring. A plug that
absorbs too much heat will have no deposits but, due to the excessive heat,
the electrodes will burn away quickly and might also lead to pre-ignition or
other ignition problems.
Pre-ignition takes place when plug tips get so hot that they glow
sufficiently to ignite the airlfuel mixture before the actual spark occurs. This
early ignition will usually cause a pinging during heavy loads and if not
corrected, can result in severe engine damage. While there are many other
things that can cause pre-ignition, selecting the proper heat range spark plug
I ensure that the spark plug itself is not a hot-spot source.
The manufacturer recommended spark plugs are listed in the Tune-
UD S~ecifications chart. This data should be compared to the
c missions Control Information label found on the powerhead itself in
US. and related markets, as the label could reflect changes made
during production that did not make it to the OE print material.
THE SHORTER THE LONGER
THE PATH. THE THE PATH, THE
FASTER THE SLOWER THE
HEAT IS DIS-HEAT IS 01s-
SIPATED AND SIPATED AND
THE COOLER THE HOTTER
SHORT YRIPHEAVY LOADS.
STOP-AND-GO
HIGH SPEEDS
SHORT Insulator Tip
LONG Insulator Tip
Slow Heal Transletfast Heal Translei
HIGHER Heal Range
LOWER Heat Range
HOT PLUGCOLD PLUG
REMOVAL & INSTALLATION
 See Figures 141 thru 149
New technologies in spark plug and ignition system design have
greatly extended spark plug life over the years. But, spark plug life can
still vary greatly with engine tuning, condition and usage. That said, it
is not uncommon for plugs to last up to 200 hours of operation or
more.
Typically spark plugs will require replacement about once a season. The
electrode on a new spark plug has a sharp edge but with use, this edge
becomes rounded by wear, causing the plug gap to increase. As the gap
increases, the plug's voltage requirement also increases. It requires a
greater voltage to jump the wider gap and about two to three times as much
voltage to fire a plug at high speeds than at idle,
 Fouled plugs can cause hard-starting, engine mis-firing or other
problems. You don't want that happening on the water. Take time, at
least once a month to remove and inspect the spark plugs. Early signs
of other tuning or mechanical problems may be found on the plugs that
could save you from becoming stranded or even allow you to address a
problem before it ruins the motor.
Tools needed for spark plug replacement include: a ratchet, short
extension, spark plug socket (there are two types; either 13/16 in. or 518 in.,
depending upon the type of plug), a combination spark plug gauge and
gapping tool and a can of anti-seize type compound, plus some dielectric
grease.
1. When removing spark plugs from multi-cylinder motors, work on one
at a time. Don't start by removing the plug wires all at once, because unless
you number them, they may become mixed up. Take a minute before you
begin and number the wires with tape.
The 40150 hp and 150-300 hp motors are equipped with a direct
ignition system on which the ignition coils are bolted directly over the
spark plugs. To remove the plugs you'll have to first tag and
disconnect the primary wiring, then remove the ignition coils
themselves from the motor. For details, refer to the Ignition Coil
procedures in the Ignition and Electrical System section.
2. For safety, disconnect the negative battery cable or turn the battery
switch OFF.
3. On some motors, especially on most mid-range and larger models,
the lower engine case may interfere with access to one or more of the lower
spark plug wires. If necessary, remove the lower engine cowling. For details,
please refer to Engine Covers (Top and Lower Cases), earlier in this section.
4 If the engine has been run recently, allow the engine to thoroughly
cool (unless performing a compression check). Attempting to remove plugs
from a hot cylinder head could cause the plugs to seize and damage the
threads in the cylinder head, especially on aluminum heads!
@ To ensure an accurate reading during a compression check, the
spark plugs must be removed from a hot engine. But, DO NOT force a
plug if it feels like it is seized. Instead, wait until the engine has cooled,
remove the plug and coat the threads lightly with anti-seize then
reinstall and tighten the plug, then back off the tightened position a
little less than 114 turn. With the plug(s) installed in this manner, re-
warm the engine and conduct the compression check.
5. Carefully twist the spark plug wire boot to loosen it, then pull the boot
using a twisting motion to remove it from the plug. Be sure to pull on the boot
and not on the wire, otherwise the connector located inside the boot may
become separated from the high-tension wire.
A spark plug wire removal tool can be used on some models (and is
recommended when it will fit) as it can make removal easier and help
prevent damage to the boot and wire assembly. Most tools have a wire
loom that fits under the plug boot so the force of pulling upward is
transmitted directly to the bottom of the boot. However, the boots used
on many of the mid-range motors are large and heavy-duty enough that
you can get a good grip on them by hand, and probably couldn't get a
wire removal tool underneath them anyway.
6. Using compressed air (and safety glasses), blow debris from the
spark plug area to assure that no harmful contaminants are allowed to enter
the combustion chamber when the spark plug is removed. If compressed air
-42 MAINTENANCE AND TUNE-UP
is not available, use a rag or a brush to clean the area. Compressed air is
available from both an air comoressor or from com~ressed air in cans
available at photography stores. In a pinch, blow up a balloon by hand and
use the escaping air to blow debris from the spark plug port(s).
Remove the spark plugs when the engine is cold, if possible, to
prevent damage to the threads. If plug removal is difficult, apply a few
drops of penetrating oil to the area around the base of the plug and
allow it a few minutes to work.
7. Using a spark plug socket that is equipped with a rubber insert to
properly hold the plug, turn the spark plug counterclockwise to loosen and
remove the spark plug from the bore.
Avoid the use of a flexible extension on the socket. Use of a flexible
extension may allow a shear force to be applied to the plug. A shear
force could break the plug off in the cylinder head, leading to costly
and/or frustrating repairs. In addition, be sure to support the ratchet
with your other hand -this will also help prevent the socket from
damaging the plug.
8. Evaluate each cylinder's performance by comparing the spark
condition. Check each spark plug to be sure they are from the same plug
manufacturer and have the same heat range rating. Inspect the threads in
Fia. 142 The lower enaine cases can aet in
Fig. 141 Spark plugs are found mounted to the way of lower sparkplugs on some Fig. 143 Once you have access, remove the
the cylinder (often through the valve cover) models spark plug cap. ..
1 1 I I
Fig. 144 . . .using a twisting motion while Fig. 145 On direct ignition models you must Fig. 146 Loosen the plug using a spark plug
pulling remove the ignition coils for access socket. ..
Fig. 149 To prevent corrosion, apply a small
Fig. 147 . . .and remove the spark plug from Fig. 148 ALWAYS thread spark plugs by amount of grease to the plug and boot
the cylinder head hand! during installation
I
the spark plug opening of the block and clean the threads before installing
the plug.
9. When purchasing new spark plugs, always ask the dealer if there has
been a spark plug change for the engine being serviced. Sometimes
manufacturers will update the type of spark plug used in an engine to offer
better efficiency or performance.
10. Inspect the spark plug boot for tears or damage. If a damaged boot is
found, the spark plug boot and possibly the entire wire will need
replacement.
11. Check the spark plug gap prior to installing the plug. Most spark
plugs do not come gapped to the proper specification.
12. Apply a thin coating of anti-seize on the thread of the plug. This is
extremely important on aluminum head engines to prevent corrosion and
heat from seizing the plug in the threads (which could lead to a damaged
cylinder head upon removal).
13. Carefully thread the plug into the bore by hand. If resistance is felt
before the plug completely bottoms, back the plug out and begin threading
again.
Do not use the spark plug socket to thread the plugs. Always carefully
thread the plug by hand or using an old plug wirelboot to prevent the
possibility of crossthreading and damaging the cylinder head bore. An
old plug wirelboot can be used to thread the plug if you turn the wire
by hand. Should the plug begin to crossthread the wire will twist before
the cylinder head would be damaaed. This trick is useful when
accessories or a deep cylinder head design prevents you from easily
keeping fingers on the plug while it is threaded by hand.
14. Carefully tighten the spark plug to specification using a torque
wrench as follows:
2.5 hp motors: 8 ft. lbs./96 inch Ibs. (11 Nm)
9.9/15 hp motors through 2004: 12.5 ft. lbs.il50 inch Ibs. (17 Nm)
25/30 hp (3-Cyl) and 40150 hp motors: 13 ft. lbsA60 inch Ibs. (18 Nm)
All other motors (including 41516 hp, 2005 and later 9.9115 hp, 25 hp
V2, and all 60-300 hp motors): 20 ft. lbs./240 inch Ibs. (28 Nm)
B Whenever possible, spark plugs should be tightened to the factory
torque specification. If a torque wrench is not available, and the plug
you are installing is equipped with a crush washer, tighten the plug
until the washer seats, then turn it 114 turn to crush the washer,
15. Apply a small amount of Suzuki Water Resistant Grease or a silicone
dielectric grease to the ribbed, ceramic portion of the spark plug lead and
inside the spark plug boot to prevent sticking, then install the boot to the
spark plug and push until it clicks into place. The click may be felt or heard.
Gently pull back on the boot to assure proper contact.
16. Connect the negative battery cable or turn the battery switch ON.
17. Test run the outboard (using a test tank or flush fitting) and insure
proper operation.
READING SPARK PLUGS
See Figures 150 thru 155
Reading spark plugs can be a valuable tuning aid. By examining the
insulator firing nose color, you can determine much about the engine's
overall operating condition.
In general, a light tanlgray color tells you that the spark plug is at the
optimum temperature and that the engine is in good operating condition.
Dark coloring, such as heavy black wet or dry deposits usually indicate a
fouling problem. Heavy, dry deposits can indicate an overly rich condition,
too cold a heat range spark plug, possible vacuum leak, low compression,
overly retarded timing or too large a plug gap.
If the deposits are wet, it can be an indication of a breached head gasket,
oil control from ring problems or an extremely rich condition, depending on
what liquid is present at the firing tip.
Also look for signs of detonation, such as silver specs, black specs or
melting or breakage at the firing tip.
Compare your plugs to the illustrations shown to identify the most
common plug conditions.
Fouled Spark Plugs
A spark plug is "fouled when the insulator nose at the firing tip becomes
coated with a foreign substance, such as fuel, oil or carbon. This coating
makes it easier for the voltage to follow along the insulator nose and leach
back down into the metal shell, grounding out, rather than bridging the gap
normally.
Fuel, oil and carbon fouling can all be caused by different things but in
any case, once a spark plug is fouled, it will not provide voltage to the firing
tip and that cylinder will not fire properly. In many cases, the spark plug
cannot be cleaned sufficiently to restore normal operation. It is therefore
recommended that fouled plugs be replaced.
Signs of fouling or excessive heat must be traced quickly to prevent
further deterioration of performance and to prevent possible engine damage.
Overheated Spark Plugs
When a spark plug tip shows signs of melting or is broken, it usually
means that excessive heat andlor detonation was present in that particular
combustion chamber or that the spark plug was suffering from thermal
shock.
Since spark plugs do not create heat by themselves, one must use this
visual clue to track down the root cause of the problem. in any case,
damaged firing tips most often indicate that cylinder pressures or
temperatures were too high. Left unresolved, this condition usually results in
more serious engine damage.
Detonation refers to a type of abnormal combustion that is usually
preceded by pre-ignition. It is most often caused by a hot spot formed in the
combustion chamber.
As air and fuel is drawn into the combustion chamber during the intake
stroke, this hot spot will "pre-ignite" the air fuel mixture without any spark
from the spark plugs.
Detonation
Detonation exerts a great deal of downward force on the pistons as they
are being forced upward by the mechanical action of the connecting rods.
When this occurs, the resulting concussion, shock waves and heat can be
severe. Spark plug tips can be broken or melted and other internal engine
components such as the pistons or connecting rods themselves can be
damaged.
Left unresolved, engine damage is almost certain to occur, with the spark
plug usually suffering the first signs of damage.
When signs of detonation or pre-ignition are observed, they are
symptom of another problem. You must determine and correct the
situation that caused the hot spot to form in the first place.
INSPECTION& GAPPING
See Figures 156 and 157
A particular spark plug might fit hundreds of powerheads and although the
factory will typically set the gap to a preselected setting, this gap may not be
the right one for your particular powerhead.
Insufficient spark plug gap can cause pre-ignition, detonation, even
engine damage. Too much gap can result in a higher rate of misfires,
noticeable loss of power, plug fouling and poor economy.
Refer to the Tune-up Specifications chart for spark plug gaps.
Check spark plug gap before installation. The ground electrode (the L-
shaped one connected to the body of the plug) must be parallel to the center
electrode and the specified size wire gauge must pass between the
electrodes with a slight drag.
Do not use a flat feeler gauge when measuring the gap on a used plug,
because the reading may be inaccurate. A round-wire type gapping tool is
the best way to check the gap. The correct gauge should pass through the
electrode gap with a slight drag. If you're in doubt, try a wire that is one size
smaller and one larger. The smaller gauge should go through easily, while
the larger one shouldn't go through at all.
Wire gapping tools usually have a bending tool attached. USE IT! This
tool greatly reduces the chance of breaking off the electrode and is much
more accurate. Never attempt to bend or move the center electrode. Also, be
careful not to bend the side electrode too far or too often as it may weaken
and break off within the engine, requiring removal of the cylinder head to
retrieve it.
2-44 MAI NANCE AND TUNE-U
@ Most Suzuki motors (probably a little more than half of the various
4-stroke models, except the 40150 hp and 150-300 hp EFI engines that
utilize direct ignition coils), are equipped with secondary spark leads or
spark plug wires to carry ignition voltage from the coils to the spark
plugs.
The job of the secondary spark leads (spark plug wires) is to carry the
high voltage necessary to fire the plug safely from the ignition coil itself to the
spark plug. What is important here is that resistance inside the wire remains
within a specified range AND the insulation remains in good conoition so
that the voltage does not arc or leak to ground. Either case (arcing voltage or
excessive resistance) will allow the ianition svstem to work outside its desian
parameters and can cause misfiring,hesitation, stumble etc.
Wires will become brittle with age and will become mere prone to cracks
or breakages that can raise resistance. This can be made worse with rough
handling (during motor top cover installation, or during maintenance and
repairs). In addition, the wire insulation will begin to break down from the
moment it is exposed to the atmosphere and to the severe conditions found
under the motor cover during normal operation. For this reason, periodic
inspection and testing of these wires are necessary to make sure the motor
continues to run in top condition.
Fig. 152 This spark plug has been left in the
powerhead too long, as evidenced by the
Fig. 150 A normally worn spark plug should
have light tan or gray deposits on the firing
tip (electrode)
Fig. 151 Acarbon-fouled plug, identified by
soft, sooty black deposits, may indicate an
improperly tuned powerhead
extreme gap. Plugs with such an extreme
gap can cause misfiring and stumbling
accompanied by a noticeable lack of power
Fig. 154 A physically damaged spark plug
Fig. 153 An oil-fouled spark plug indicates a may be evidence of severe detonation in
powerhead with worn piston rings or a that cylinder. Watch the cylinder carefully Fig. 155 A bridged or almost bridged spark
malfunctioning oil injection system that between services, as a continued detonation plug, identified by the build-up between the
allows excessive oil to enter the combustion will not only damage the plug but will most electrodes caused by excessive carbon or
chamber likely damage the powerhead oil build up on the plug
TESTING
DERATE
+ See Figures 158,159 and 160
Each time you remove the engine cover, visually inspect the spark plug
wires for burns, cuts or breaks in the insulation. Check the boots on the coil
and at the spark plug end. Replace any wire that is damaged.
Except on Direct Ignition (Dl) models, once a year, usually when you
change your spark plugs, check the resistance of the spark plug wires with
an ohmmeter. Wires with excessive resistance will cause misfiring and may
make the engine difficult to start. In addition worn wires will allow arcing and
misfiring in humid conditions.
Remove the spark plua wire from the en~ine. Test the wires by connecting
one lead of an ohmmeterto the coil end of the wire and the other lead to the
spark plug end of the wire. Keep in mind though, that depending upon the
model vou mav have to remove a resistor cao from the spark olua end of the
wire first. To determine this, along with the proper test ~~ecifications,
please
refer to the charts found in the Ignition and Electrical System section,
specifically the ones entitled Ignition Testing Specifications -Carbureted
Motors, andlor Ignition Components and Fuel Injector Sensor Testing,
depending on the motor.
If a spark plug wire is found to have excessive resistance (much higher
resistance than specified), the entire set should be replaced.
Fig. 156 Use a wire-type spark plug gapping tool to check the
distance between center and ground electrodes
Keep in mind that just because a spark plug wire passes a
resistance test doesn't mean that it is in good shape. Cracked or
deteriorated insulation will allow the circuit to misfire under load,
especially when wet. Always visually check wires to cuts, cracks or
breaks in the insulation. If found, run the engine in a test tank or on a
flush device either at night (looking for a bluish glow from the wires
that would indicate arcing) or while spraying water on them while
listening for an engine stumble.
Regardless of resistance tests and visual checks, it is never a bad idea to
replace spark plug leads at least every couple of years, and to keep the old
ones around for spares. Think of spark plug wires as a relatively low cost
item that whose replacement can also be considered maintenance.
REMOVAL& INSTALLATION
When installing a new set of spark plug wires, replace the wires one at a
time so there will be no confusion. Coat the inside of the boots with Suzuki
Water Resistant Grease or dielectric grease to prevent sticking. Install the
boot firmly over the spark plug until it clicks into place. The click may be felt
or heard. Gently pull back on the boot to assure proper contact. Repeat the
process for each wire.
It is important to route the new spark plug wire the same as the
original and install it in a similar manner on the powerhead. Improper
routing of spark plug wires may cause powerhead performance
problems.
Fig. 157 Most plug gapping tools have an adjusting fitting used to
bend the ground electrode
Fig. 158 Except for direct ignition motors, Fig. 160 Most models use resistor caps
visually inspect the spark plug boot and Fig. 159 ...all the way back to the ignition which must be tested separately from the
wire.. . coils for signs of wear or damage wire
components for signs of obvious defects. Look for signs of burnt, cracked or
INSPECTION
Modern electronic ignition systems have become one of the most reliable
components on an outboard. There is very little maintenance involved in the
operation of these ignition systems and even less to repair if they fail. Most
systems are sealed and there is no option other than to replace failed
components.
See Figures 161,162 and 163
In simple terms, synchronization is timing the fuel system to the ignition.
Timing and synchronization ensures that as the throttle is advanced to
increase powerhead rpm, the fuel and the ignition systems are both
advanced equally and at the same rate (i.e. "in sync").
Various models have unique methods of checking ignition timing. As
appropriate, these differences will be explained in detail in the text.
Any time the fuel system or the ignition system on a powerhead is
serviced to replace a faulty part or any adjustments are made for any
reason, powerhead timing and synchronization must be carefully checked
and verified.
Depending on the engine, adjustment of the timing and synchronization
can be extremely important to obtain maximum efficiency. The powerhead
cannot perform properly and produce its designed horsepower output if the
fuel and ignition systems have not been precisely adjusted. We say,
depending on the engine because more than half of the models covered by
here are equipped an EFI system, and all but one carbureted powerhead
family is equipped with only a single carburetor, and almost everything here
requires few, if any adjustments once properly installed.
As a matter of fact, because of the US.EPA or EU regulated carburetors
used on most of the motors covered here, very few adjustments are possible
even on most carburetors. There are no periodic mixture adjustments
necessary on ANY of the motors covered here. Most high-speed jets are
fixed units and the low speed mixture screws are usually sealed to prevent
unnecessary tampering. However, any carburetor will require initial set-up
and adjustment after disassembly or rebuilding. Also, on any motor equipped
with multiple carburetors (which is only the 25/30 hp 3-cyl motors), the carbs
I require synchronization with each other after anytime they have been
removed or separated.
Though some of the motors covered here have adjustable idle speeds,
pretty much all of the motors use electronically controlled ignition and timing
systems that allow for timing checks, but are otherwise completely self-
adjusting.
Still a timing check can tell the operator if the ignition system is doing its
job correctly, so all (or nearly all) models will have timing indicators on the
manual starter or flywheel cover and timing marks (usually molded) on the
broken insulation. Replace wires or components withobvious defects. If
spark plug condition suggests weak or no spark on one or more cylinders,
perform ignition system testing to eliminate possible worn or defective
components.
If trouble is suspected, it is very important to narrow down the problem to
the ignition system and replace the correct components rather than just
replace parts hoping to solve the problem. Electronic components can be
very expensive and are usually not returnable.
flywheel itself. A timing light is normally used to check the ignition timing with
the powerhead operating (dynamically).
Before making ANY adjustments to the ignition timing or
synchronizing the ignition to the fuel system, both systems should be
verified to be in good working order.
The following equipment is essential and is called out repeatedly in this
section. This equipment must be used as described, unless otherwise
instructed by the equipment manufacturer. Naturally, the equipment is
removed following completion of the adjustments.
For any adjustment under load, the manufacturer either recommends the
use of a test wheel (when available) or, more frequently, the use of a
standard propeller in order to put a load on the engine and propeller shaft.
Both methods are used to prevent the engine from excessive rpm.
Timing Light -During many procedures in this section, the appropriate
timing marks on the flywheel must be aligned with a stationary timing mark
on the engine (usually manual starter or flywheel cover) while the powerhead
is running. Only through use of a timing light connected to the No. 1 spark
plug lead, can the timing mark on the flywheel be observed while the engine
is operating.
* Tachometer -A tachometer connected to the powerhead must be used
to accurately determine engine speed during idle and high-speed
adjustment. Engine speed readings generally range from 0-6,000 rpm in
increments of 100 rpm. Choose a tachometer with solid state electronic
circuits which eliminates the need for relays or batteries and contribute to
their accuracy. For maximum performance, the idle rpm should be checked
or adjusted under actual operating conditions. Under such conditions it might
be necessary to attach a tachometer closer to the powerhead than the one
installed on the control panel.
B Because the 90-300 hp 4-strokes use an offset crankshaft with a
separate crankshaft driven gear the motors were designed to rotate
COUNTERCLOCKWISE in order to drive the driven gear and driveshaft
the same standard CLOCKWISE direction that other motors rotate. In
this way the gearcases for these Left Hand turning powerheads can
still utilize standard Right Hand (standard rotation) propellers.
Fig. 161 You will normally find a timing Fig. 163 Timing marks themselves are
pointer integrated into the manual starter.. . 1 Fig. 162 .. .or flywheel cover, as equipped usually molded into the flywheel
Flywheel Rotation -The instructions may call for rotating the flywheel
until certain marks are aligned with the timing pointer. When the flywheel
must be rotated, always move the flywheel in the indicated direction
(Clockwise on most models, EXCEPT the left-hand rotation motors covered
here, which are the 90-300 hp motors, which normally rotate
Counterclockwise). If the flywheel should be rotated in the opposite direction,
the water pump impeller vanes would be twisted. Should the powerhead be
started with the pump tangs bent back in the wrong direction, the tangs may
not have time to bend in the correct direction before they are damaged or
destroyed. Keep in mind that even the smallest amount of damage to the
water pump will affect cooling of the powerhead
Test Tank -Since the engine must be operated at various times and
engine speeds during some procedures, a test tank or moving the boat into a
body of water, is necessary. If installing the engine in a test tank, outfit the
engine with an appropriate test propeller
Water must circulate through the lower unit to the powerhead anytime
the powerhead is operating to prevent damage to the water pump in the
lower unit. Just a few seconds without water will damage the water
pump impeller.
E Remember that in most applications the powerhead will not start
without the emergency tether in place behind the kill switch knob.
Never operate the powerhead above a fast idle with a flush attachment
connected to the lower unit. Operating the powerhead at a high rpm
with no load on the propeller shaft could cause the powerhead to
runaway causing extensive damage to the unit.
ADJUSTMENTS
Very few adjustments are possible on these motors. The following
procedures provide instructions how to checklset the idle speed, as well as
to check the ignition timing on these motors. These motors are equipped with
a digital Capacitor Discharge Ignition (CDI) system that contains a single CDI
and coil unit which integrates the ignition coil and pulser core. All timing
adjustments are handled internally, though a timing check may be used to
insure the system is operating properly.
One carburetor was specified for use on these models, the Walbro LMJ-
26, and it is listed as having a pre-set idle mixture adjustment which was
sealed at the factory. Still an idle speed procedure is available which uses a
spring-loaded idle speed screw found on top of the carburetor to adjust the
throttle plate at the idle position.
Idle Speed Adjustment
+ See Figures 164 and 165
Idle speed is adjusted with the gearcase in neutral so this adjustment can
occur with the motor mounted on the boat and in the water, in a test tank or
even running on a suitable flushing fitting. But the idle speed should later be
checked and verified in gear, especially if the motor is to be used for trolling
at idle.
1. Remove the motor top cover for access as follows:
a. Tie a slipknot in the rope inside the motor cover (between the cover
and the manual starter assembly) so the rope cannot retract into the recoil
reel once the starter grip is removed.
A quick trick besides using a knot is to use a metallic clamp or tool
like vise-grips to grab the rope, just make sure the rope doesn't
become frayed or damaged if you use such a method.
b. Free the knot holder from the starter grip, then remove the knot and
carefully pull the starter grip from the end of the rope.
c. With the starter grip out of the way you are now free to remove the
motor cover.
d. Install the starter grip and the holder to the end of the rope and
loosen the knot (or clamping tool) which had been holding the rope of the
manual starter housing.
2. Start by making sure the link mechanism and the carburetor throttle
valve operates smoothly without binding.
3. Attach an inductive tachometer to the spark plug high tension cord.
4. Place the motor in a test tank or supply a suitable source of cooling
water, then start the powerhead and allow it to reach normal operating
temperature. Let the motor run for about 5 minutes or so.
Water must circulate through the lower unit to the engine any time the
engine is run to prevent damage to the water pump in the lower unit.
Just a few seconds without water will damage the water pump.
5. With the outboard at normal operating temperature and operating in
NEUTRAL, make sure the throttle is fully closed, then check the idle speed,
it should be about 1900 rpm (though a range of 1800-2000 is acceptable). If
the motor is operating out of the specified range locate the idle speed screw,
on the top of the carburetor, near the ignition coil and spark plug boot,
between the throttle control cable and the choke rod. The idle speed screw is
a spring-loaded, horizontally mounted screw positioned where it can directly
affect the throttle linkage. Turn the idle speed screw CLOCKWISE to
increase idle speed or COUNTERCLOCKWISE to decrease speed. Make
small adjustments, then open and close the throttle manually, waiting each
time for a steady idle speed, before making the next adjustment.
6. Once idle speed is properly set you can move on to checking the
Ignition Timing.
Ignition Timing
+ See Figure 166
As stated earlier in this section, timing is controlled by the CDI unit (which
integrates the ignition coil and the pulse~coils into one housing). At least
annually or every 200 hours of operation you should check ignition timing to
verify the system is operating properly. The Idle Speed must be properly
adjusted before checking timing.
Unfortunately Suzuki only provided one specification and though they
claim this spec is for idle timing we're skeptical, but at the time of writing we
didn't have access to a test motor to check it. Regardless, IF the
specification is correct, you CAN check this setting in a test tank or on a
flush fitting, however because there is so much advance listed in this spec,
IF the check does not agree with specification then we'd recommend you
1 -Idle Speed Screw
Fig. 166 Checking idle ignition timing -2.5
hp motors
double-check by testing at WOT. If you need to check at WOT also, the
adjustment MUST be performed in a test tank or on a launched vessel so
that you can run the motor at WOT under load. DO NOT attempt to check
the WOT timing on a flush fitting.
1. Provide a suitable source of cooling water,
2. Attach a timing light cord to the spark plug wire. One with a built-in
tach can be handy otherwise you'll want to attach a tachometer too.
3. Start and allow the engine to warm up to normal operating
temperature.
4. There's a timing window and pointer in the manual starterlflywheel
cover toward the port side of the motor, just behind where the starter rope
enters the housing. Run the motor at idle while pointing the timing light at the
housing and watching the marks on the flywheel. Timing should be
approximately 30' BTDC at idle. This may be represented by numbered
marks, OR it may just be the larger timing mark (slash) surrounded by
smaller slashes. A small variance is normally allowable.
Htiming is not correct, the Ignition System should be checked for
faults and repairedlreplaced as necessary.
5. Shut the powerhead down, then remove the tachometer andlor timing
light.
ADJUSTMENTS
Very few adjustments are possible on these motors. The following
procedures provide instructions how to checkset the idle speed, as well as
to check the ignition timing on these motors. These motors are equipped with
a digital Capacitor Discharge Ignition (CDI) system that contains a single CDI
and coil unit which integrates the ignition coil and pulser core. All timing
adjustments are handled internally, though a timing check may be used to
insure the system is operating properly.
It appears that a number of different carburetors may have been used on
these models depending on both the year and the intended market. Versions
of the Mikuni BV-22-14 (415 hp) or Mikuni BV-22-16 (6 hp) may be found
through 2004 and may or may NOT utilize an adjustable low speed (piloUidle
mixture) screw on the top of the carburetor (opposite side from the fuel inlet
fitting) threaded downward at about a 45' angle (again depending on the
particular carburetor ID and whether or not this screw was used and sealed
or not used at all, for more details, please refer to the Carburetor Adjustment
chart in the Fuel System section).
Later models are equipped with various Keihin carburetors and the
exploded views generally DO NOT SHOW a low speed mixture screw
(though that does not mean for certain none is there, as there is a spec for
some versions of the 2004 6 hp motor with a Keihin carburetor). Specs on
other Keihin carburetor motors simply say the low speed is "preset" and we
cannot determine for sure at this time whether that is to discourage
tampering or if truly there is no pilot screw and only a fixed pilot jet on these
models.
Idle Speed Adjustment
See Figure 167
Idle speed is adjusted with the gearcase in neutral so this adjustment can
occur with the motor mounted on the boat and in the water, in a test tank or
even running on a suitable flushing fitting. However, keep in mind that if
you're going to check the WOT timing later, you're going to need a test tank
or to launch the boat.
1. Start by making sure the link mechanism and the carburetor throttle
valve operates smoothly without binding.
2. Attach an inductive tachometer to the spark plug high tension cord.
3. As mentioned earlier, the manufacturer only gives information on
adjusting the idle MIXTURE on certain carburetors, for details on which
carburetors contain adjustments (according to year, model and carb ID code)
please refer to the Car
the carburetor or powe
screwlneedle (if equipp
that now. Rotate the low speed needle (normally located on the top of the
carb, threaded downward at an angle with the head facing toward the
manual starter assembly), clockwise SLOWLY and GENTLY until the needle
Fig. 167 Idle speed and mixture screws on a 41516 hp motor with a
Mikuni carb
is lightly seated. Back the needle out exactly the proper number of turns as
designated by the chart.
4. Start the powerhead and allow it to reach normal operating
temperature.
Water must circulate through the lower unit to the engine any time the
engine is run to prevent damage to the water pump in the lower unit.
Just a few seconds without water will damage the water pump.
5. With the outboard at normal operating temperature and operating in
NEUTRAL, idle speed should be about 1300 rpm (though a range of 1250-
1350 is acceptable). If the motor is operating out of the specified range
locate the idle speed screw, on the opposite side of the carburetor from the
manual starter (facing the front of the motor). The idle speed screw is a
horizontally mounted screw positioned just forward of the throttle linkage.
Turn the idle speed screw CLOCKWISE to increase idle speed or
COUNTERCLOCKWISE to decrease speed. Make small adjustments,
waiting each time for a steady idle speed, before making the next
adjustment.
6. On models with an adjustable idle mixture, if necessary tweak the
screw positioning with up to 114 turn from standard positioning. Turning the
mixture screw CLOCKWISE will lean out the mixture further, while turning it
COUNTERCLOCKWISE will enrichen the mixture. Make only a small
adjustment, as necessary to stabilize idle.
7. Once idle speed is properly set you can move on to checking the
Ignition Timing.
Ignition Timing
See Figure 168
As stated earlier in this section, timing is controlled by the CDI unit (which
integrates the ignition coil and the pulser coils into one housing). At least
annually or every 200 hours of operation you should check ignition timing to
verify the system is operating properly. The Idle Speed must be properly
adjusted before checking timing.
Checking the timing at idle speed should be sufficient and can be
performed in a test tank or on a flush fitting, but if you want to check that the
motor is advancing properly by checking WOT timing, then you'll need to use
a test tank or launch the boat. DO NOT attempt to check the WOT timing on
a flush fitting.
1. PY k"c-:suitable source of cooling water; a test tank, launch the
boat 014 a flush fiiting (unless you want to check WOT timing).
2. Attach a timing light cord to the spark plug wire. One with a built-in
tach can be handy otherwise you'll want to attach a tachometer too,
especially if you are checking WOT timing and not just idle timing.
ADJUSTMENTS
on timing using the pointerlwindow in the
3. Start and allow the engine to warm up to normal operating
temperature.
4. There's a timing window and pointer in the manual startertflywheel
cover toward the front of the motor, just behind the air intake opening for the
carburetor. Point the timing light at the mark. Idle timing should be either 6Â
BTDC for 415 hp models through 2004 models or 3' BTDC for 2005 or later
415 hp models. On 6 hp models the idle timing should be loBTDC for 2003
models and also 2004 models equipped with a Mikuni carburetor, and should
be 3' BTDC for 2004 models equipped with a Keihin carburetor or all 2005
or later models.
5. WOT timing is checked in the same basic fashion, except that you
must run the gearcase under a load (in water, with a suitable prop) to
prevent a runaway powerhead. Advance the motor to full throttle while
watching the timing marks, the timing should advance to 26.5' BTDC for
2002-2004 415 hp models or 28' BTDC for 2005 or later 415 hp models and
ALL 6 hp models (including 2003-04). Keep in mind that no maintenance
recommendation was provided by the manufacturer to check timing at WOT
and this timing spec is the maximum advance listed in the design specs for
the ignition system. In other words, we wouldn't worry if a check shows
slightly less advance, as long as the motor seems to otherwise be running
properly.
M If timing is not correct, the Ignition System should be checked for
faults and repairedlreplaced as necessary.
6. Shut the powerhead down, then remove the tachometer and/or timing
light.
Throttle Stop Screw
1
Throttle Lever
Through 1996
88 mm (3.46 in.)
1996 112 and Later
86 mrn (3.39 in.)
Very few adjustments are possible on these motors. The following
procedures provide instructions how to adjust the throttle control cables
(tiller) or rod (remote), to checklset the idle speed (and idle mixture if
adjustable), as well as to check the ignition timing.
These motors are equipped with a digital Capacitor Discharge Ignition
(CDI) system which utilizes a CDI unit mounted on the powerhead, as well
as both a charge coil (in a stator) and a pulser coil (sensorttrigger coil) which
are mounted under the flywheel. The CDI unit controls all ignition timing
based on signals from the pulser coil, so no adjustments are necessary or
possible.
It appears that Suzuki (as well as the EPA) wants to discourage tampering
with the idle mixture on most of these motors. The factory service information
gives NO specifications or details on initial setting of the pilot (idle mixture)
screw on most years/models/carburetor IDS. As a matter of fact many of the
exploded views don't even show that the needle exists, however it is shown
and mentioned in some of the carburetor "theory of operation" information
and in at least one of the Mikuni exploded views for these models.
Regardless, idle mixture adjustment isn't a periodic adjustment and should
only be performed after major component (powerhead or carburetor)
overhaul or replacement.
Throttle Control CableIRod InstallationIAdjustment -Mikuni Models
See Figures 169,170 and 171
Mikuni carburetors should be found on mosUall of these motors through
2004 models. This installationladjustment procedure ccu/eia bolh tiller and
remote models.
The throttle control cablestrod should not require any periodic attention,
however, should the cables or related components be replaced, an initial
adjustment is necessary to make sure they operate properly. Adjustment will
ensure that they allow the throttle to both open fully at Wide Open Throttle
(WOT) operation and close fully when the throttle is returned to idle.
This procedure starts with the cables already disconnected due to service.
1. Locate the throttle stop screw (also known as an idle stop, idle speed
or idle adjustment screw) on the side of the carburetor throttle body, where it
is threaded so it contacts the throttle lever to hold it open slightly at idle.
Loosen the screw (turning it counterclockwise) until it no longer contacts the
throttle lever.
2. Adjust the throttle rod to a length of 3.46 in. (88mm) for models
through 1996 or to 3.39 in. (86mm) for 1996 It2 and later models. This
distance is measured between the centers of the two connector holes.
3. Gently press fit the throttle rod onto the ball pivots of the throttle
drum and the throttle arm.
Stopper 'I\%-/-^'^^""^
Connector
Holder
Drum
nmm
Lock Nut
mm
Fig. 170 After throttle rod adjustment, make
sure the throttle lever contacts the WOT
stop while the throttle drum still has a Fig. 171 Finally, close the throttle and check
smidge of clearance the throttle lever again
4. Rotate the throttle drum CLOCKWISE and make sure that the throttle
lever on the carburetor hits the WOT stop while there is still about 0-1mm of
clearance between the throttle drum and the drum stopper. If the drum hits
the stopper first, adjust the length of the throttle rod until the throttle lever
JUST hits the stopper first.
5. On Tiller control models, fully close the throttle control grip.
6. On Remote control models, position the control handle in Neutral.
7. Secure the throttle cable to the holder by fitting the cable groove into
a slot on the holder, then install the bracket to secure the cable by the
bracket retaining screw.
8. Thread the connector onto the cable, then turn the throttle drum
counterclockwise until just a tiny amount of clearance exists at the other end
of the throttle lever.
9. While pushing the cable end back towards the holder, adjust the
connector until the center of the connector aligns with the center of the ball
pivot on bottom of the drum. Once it is aligned, gently press fit the connector
on the ball pivot and tighten the locknut on the cable connector to hold this
position securely.
10. Finally, double-check to make sure the throttle lever still contacts the
WOT stopper with the throttle fully opened, and that some clearance still
exists at the throttle lever with the throttle control fully closed. If necessary,
loosen the locknut and readjust the connector to achieve both of these
conditions.
Throttle Control CableIRod InstallationIAdjustment -Keihin CarbKiller
See Figure 172
The throttle control cables should not require any periodic attention,
however, should the cables or related components be replaced, an initial
adjustment is necessary to make sure they operate properly. Adjustment will
ensure that they allow the throttle to both open fully at Wide Open Throttle
(WOT) operation and close fully when the throttle is returned to idle.
This procedure starts with the cables already disconnected due to service
1 Route the 2 throttle cables into the throttle drum on the powerhead
and position the locknuts loosely into the cable holder.
2. Check the length of the throttle rod (which connects the throttle drum
to the carburetor throttle arm) it should be 3.78 in (96mm) as measured from
the centers of the ball pivots on the connectors at each end. If necessary,
free one or both of the connectors and adjust the rod to the proper length,
then secure it back over the drum lever and the carburetor throttle arm.
3. Turn the throttle control to WOT position, then adjust the UPPER
cable by turning the locknuts until the throttle drum stopper is in contact with
the cylinder block stopper.
4. Turn the throttle control to the closedlidle position, then adjust the
LOWER cable by turning the locknuts until the throttle drum mark is aligned
with the cylinder block rib.
5. With the throttle control still in the closedhdle position now check to
make sure there is clearance between the throttle drum and throttle control
lever. Then secure both the throttle cables using the locknuts.
6. Open the throttle again to the WOT position, now make sure there is
0-2mm (0.0-0.08 in.) of clearance between the carburetor full open stopper
and the lever at the same time that the throttle drum stopper is in contact
with the cylinder block stopper.
7. Fully loosen the throttle tension adjuster, then open the throttle
control grip fully and release. Make sure the throttle control grip returns to
the closed position via the spring force on the carburetor. If the grip does
NOT return, the throttle cable tension is too tight and the cables should be
readjusted.
Throttle Control Rod Adjustment -Keihin GarbIRemote Models
See Figure 173
The throttle control link rod should not require any periodic attention,
however, should the rod or related components be replaced, an initial
adjustment is necessary to make sure it operates properly. Adjustment will
ensure that it allows the throttle to both open fully at Wide Open Throttle
(WOT) operation and close fully when the throttle is returned to idle.
This procedure starts with the throttle rod already disconnected due to
service.
1. Check the length of the throttle rod (which connects the throttle drum
to the carburetor throttle arm) it should be 3.48 in (88.5mm) as measured
from She centers of the ball pivots on the connectors at each end. If
necessary, turn one or both of the connectors and adjust the rod to the
A -Stopper1 & 2 -Throttle Cable
B -Cylinder Block Stopper
3 -Drum
C -Mark4 -Cable Holder
D -Rib5 -Throttle Rod
E -Stopper (Full Open) 6 -Throttle Lever
F -Lever7 -Carb. Throttle Arm
L -Length of throttle rod 99 mm8 & 9-Lock Nuts
I
I
(3.78 in.)
X/Y = Clearance
I
I
Fig. 172 Throttle control cable installation and adjustment -Tiller
9.9115 hp motors with Keihin Garbs
1 -Throttle Rod A -Drum Stopper
2 -Throttle Lever B -Clyllnder Block Stopper
3 -Carb Throttle Arm E -Carb WOT Stopper
4 -Throttle Drum F -Lever
I
I
Fig. 173 Throttle control rod adjustment -Remote 9.9115 hp with
Keihin Carb
proper length, then secure it back over the drum lever and the carburetor
throttle arm.
2. Rotate the throttle drum clockwise until the drum stopper contacts the
cylinder block stopper. At this point check that there is 0-2mm (0.0-0.08 in.)
of clearance between the carburetor full open stopper and the lever. If there
is no clearance at all, or too much clearance, adjust the length of the rod as
necessary.
Idle Speed Adjustment
See Figure 174
Idle speed itself can be generally be adjusted with the gearcase in either
neutral or in gear so this adjustment CAN occur with the motor mounted on
the boat and in the water, in a test tank or even running on a suitable
flushing fitting. However, if you need to adjust the low speed mixture (on
models where that is possible) andlor check the idle speed in gear, you'll
need a test tank or to at least launch the boat. Also, keep in mind that for
models through 1996 Suzuki only provided specifications for IN-GEAR idle
speed, so at least on those models you'll have to use a test tank or launched
craft.
1. Start by making sure the link mechanism and the carburetor throttle
valve operates smoothly without binding.
2. Attach an inductive tachometer to the No 1. cyl. spark plug high
tension cord.
3. As mentioned earlier, the manufacturer does not give much
information on adjusting the idle MIXTURE for these carburetors, but specs
do exist for enough models that we think there is a good chance that there is
an idle mixture screw under the cover of most sealed units. Remember that
regardless of whether or not the screw is accessible this is NOT a periodic
adjustment and should only be performed after rebuilds, repairs or other
modification. Since some early versions of the Mikunis and all of the Keihins
have specifications for initial low speed screw settings we suggest that if you
didn't think to seat the old screw before removal and count the number of
turns, you can probably use those older specs as a starting point (for details,
please refer to the Initial Low Speed Setting given in the Carburetor Set-Up
Specifications Chart under the Fuel System section). If the carburetor or
powerhead was rebuiltheplaced and the low speed screwlneedle (if
equipped) was not given a preliminary adjustment yet, do that now. Rotate
the low speed needle (normally located on the top of the carb, threaded
downward at an angle with the head facing toward the manual starter
assembly), clockwise SLOWLY and GENTLY until the needle is lightly
seated. Back the needle out exactly the proper number of turns as
determined before it was removed or using the specifications mentioned
earlier.
4. Start the powerhead and allow it to reach normal operating
temperature.
Water must circulate through the lower unit to the engine any time the
engine is run to prevent damage to the water pump in the lower unit.
Just a few seconds without water will damage the water pump.
5. With the outboard at normal operating temperature and operating in
NEUTRAL, idle speed should be about 1050-11 50 rpm for 1996 112 to 2004
models (all with Mikuni carbs), or 850-950 rpm for 2005 or later models (with
Keihin carbs). For early models through 1996, Suzuki only provided a spec
of 950-1050 for idle speed IN GEAR, which would probably result in about
1050-1150 rpm in Neutral, but just to be sure, check in gear first on these
motors. If the motor is operating out of the specified range locate the idle
speed screw, on the side of the carburetor body. The idle speed screw is
threaded downward at an angle through a spring and bracket on the side of
the carburetor, so the tip can protrude and contact the carburetor throttle
lever. Turn the idle speed screw CLOCKWISE to increase idle speed or
COUNTERCLOCKWISE to decrease speed. Make small adjustments,
waiting each time for a steady idle speed, before making the next
adjustment.
6. If you are running it in a test tank or on a launched craft, you may
want to check the idle speed in gear as well for 1996 112 and later models. If
so, shift into forward and increase engine speed above idle, then allow it to
drop back down to idle. The motor should idle in gear at about 950-1050 rpm
for models through 2004 or 820-920 rpm for 2005 or later models. If the
motor is operating out of the specified range adjust further using the idle
speed screw.
JNDER COVER JET
IDLE STOP
(SPEED)
SCREW
7. On models with an adjustable idle mixture, if it was necessary to
adjust it earlier, it may also be necessary to tweak the screw positioning now,
with up to 114 turn from standard positioning. Turning the mixture screw
CLOCKWISE will lean out the mixture further, while turning it
COUNTERCLOCKWISE will enrichen the mixture. Make only a small
adjustment, as necessary to stabilize idle. If this adjustment is made, run the
engine at or near full throttle for a minute, then quickly drop it to idle. If the
motor coughs, pops or doesn't want to drop back down to idle, the mixture is
likely still a little too lean. Make a small adjustment, waiting 15 seconds or
more for it to stabilize, then try again. The mixture should be considered
good once a STABLE idle is achieved.
8. Once idle speed is properly set you can move on to checking the
Ignition Timing.
Ignition Timing
+ See Figure 175
As stated earlier in this section, timing is controlled by the CDI unit based
on signals from a pulser coil. At least annually or every 200 hours of
operation you should check ignition timing to verify the system is operating
properly. The Idle Speed must be properly adjusted before checking timing.
Checking the timing at idle speed should be sufficient and can be
performed in a test tank or on a flush fitting, but if you want to check that the
motor is advancina ~ro~erlv
bv checkina WOT timina. then vou'll need to use
a test tank or launch the boat.'^^ ~0~attem~t
to check the WOT timing on
a flush fitting.
1. Provide a suitable source of cooling water; a test tank, launch the
boat OR a flush fitting (unless you want to check WOT timing).
2. Attach a timing light cord to the No. 1 spark plug wire. One with a
built-in tach can be handy otherwise you'll want to attach a tachometer too,
especially if you are checking WOT timing and not just idle timing.
3. Start and allow the engine to warm up to normal operating
temperature.
4. There's a timing window and pointer in the manual starterlflywheel
cover on the port side of the motor. Point the timing light at the mark. Idle
timing should be either 5ÂBTDC at 1100 rpm for models through 2004 or 5Â
ATDC at 1000 rpm for 2005 and later models.
5. WOT timing is checked in the same basic fashion, except that you
must run the gearcase under a load (in water, with a suitable prop) to
prevent a runaway powerhead. Advance the motor to full throttle while
watching the timing marks, the timing should advance to 30' or 35" BTDC,
depending on the year and model. For more details, please refer to the
Tune-up Specifications chart in this section, but keep in mind that no
maintenance recommendation was provided by the manufacturer to check
timing at WOT and this timing spec is the maximum advance listed in the
design specs for the ignition system. In other words, we wouldn't worry if a
check shows slightly less advance, as long as the motor seems to otherwise
be running properly.
Fig. 174 Carburetor adjustment points -Mikuni shown, Keihin Fig. 175 Use the pointer and window on the manual starterlflywheel
similar cover to check timing
B If timing is not correct, the Ignition System should be checked for
faults and repairedlreplaced as necessary.
6. Shut the powerhead down, then remove the tachometer and/or timing
light,
ADJUSTMENTS
DERATE
Very few adjustments are possible on these motors. The following
procedures provide instructions how to installladjust the throttle control
cables on both tiller or remote motors, to checkket the idle speed, as well as
to check the ignition timing.
These motors are equipped with a digital Capacitor Discharge Ignition
(CDI) system which utilizes a CDI unit mounted on the powerhead, as well
as both a charge coil (in a stator) and a triggerlpulser coil (crankshaft
position sensor) which are mounted under the flywheel. The CDI unit
controls all ignition timing based on signals from the pulser coil, so no
adjustments are necessary or possible.
It appears that Suzuki (as well as the EPA) wants to discourage tampering
with the idle mixture on these motors. Though the factory service information
lists an initial low-speed screw setting (of 2 114 -3 114 turns out from a lightly
seated position) it also notes that it is "pre-set" and "sealed." The factory
service information then gives NO further information or details on setting the
pilot (idle mixture) screw. As a matter of fact the exploded view doesn't even
show that the needle exists, however it is shown and mentioned in some of
the carburetor "theory of operation'' information for these models (as being
located horizontally in the carburetor cover). Regardless, idle mixture
adjustment isn't a periodic adjustment and should only be performed after
major component (powerhead or carburetor) overhaul or replacement.
Throttle Control Cable Installation/Adjustment -Tiller Models
+ See Figure 176
The throttle control cables should not require any periodic attention, other
than to double-check that the adjustment is correct before checking adjusting
idle speed or checking ignition timing. However, should the cables or related
components be replaced, an initial adjustment is necessary to make sure
they operate properly. Adjustment will ensure that they allow the throttle to
both open fully at Wide Open Throttle (WOT) operation and close fully when
the throttle is returned to idle.
This procedure starts with the cables already disconnected due to service.
1. Rotate the throttle grip to the fully closed throttle position.
2. Align the matchmark on the throttle cam (the linkage which is
attached to the cable drum the powerhead) with the center of the carburetor
throttle lever roller.
3. Connect the throttle cable ends to the drum and to the cable holder
bracket. Turn each cable locknut set just enough to secure the inner cable
(length of cable between the locknut and drum) with no sag. Repeat for the
other cable.
4. Once the inner portions of the cables are in position without sag,
tighten each cable's set of locknuts against the bracket.
5. Now using the throttle control grip on the tiller handle, open and
close the throttle a few times. Check that when the grip is turned to the fully
closed position the throttle cam matchmark still aligns with the center of the
throttle roller. Readjust as necessary.
Throttle Control Cable InstallationIAdjustment -Remote Models
+ See Figure 177
The throttle control cables should not require any periodic attention, other
than to double-check that the adjustment is correct before checking adjusting
idle speed or checking ignition timing. However, should the cables or related
components be replaced, an initial adjustment is necessary to make sure
they operate properly. Adjustment will ensure that they allow the throttle to
both open fully at Wide Open Throttle (WOT) operation and close fully when
the throttle is returned to idle.
This procedure starts with the cables already disconnected due to service.
1. Connect the throttle cable ends to the drum and to the cable holder
bracket up near the carburetor AND to the interlink throttle lever and cable
bracket down near the oil filter.
2. Align the matchmark on the interlink throttle lever with the cylinder
block rib (the block rib is located on the powerhead, just below the right edge
of the cable bracket, when aligned the matchmark on the interlink throttle
lever will be at about the 12 o'clock position).
3. Holdina the interlink throttle lever in this oasXon alian the matchmark
on the throttlecam (on the other end of the cables) with the center of the
carburetor throttle lever roller.
4. Holding both levers in these positions (another set of hands can be
helpful here) adjust the cable locknuts to remove the play from the cables.
Once the cables are both set with minimal play (but not set so tight as to
preload them), tighten the locknuts securely.
5. Using the remote throttle lever move the throttle from idle to WOT
and back again a few times. Make sure the linkage moves smoothly and
without binding. Once finished, recheck the alignment of the levers and
matchmarks.
6. Readjust as necessary.
ThrottleCam
Throttl
Drum
Fig. 176 Throttle control cable installation and adjustment -Tiller
25 hp V2 motors
A -Throttle Cable
B -Throttle Drum
C -Interlink Throttle Lever
D -Cable Brackets
E -Throttle Cam
F -Throttle Lever Roller
G -Match Mark
H -Clyllnder Block Rib
I -Cable Lock Nuts
Fig. 177 Throttle control cable installation and adjustment -Remote
25 hp V2 motors
Idle Speed Adjustment
Idle speed itself can be adjusted with the gearcase in neutral so this
adjustment CAN occur with the motor mounted on the boat and in the water,
in a test tank or even running on a suitable flushing fitting. However, if you
need to adjust the low speed mixture (on models where that is possible)
and/or check the idle speed in gear (such as to verify speed for trolling) or if
you plan on checking ignition timing next at Wide Open Throttle (WOT),
you'll need a test tank or to at least launch the boat. Similarly, we always
think it is a good idea to adjust the idle speed IN GEAR (in the water), so
we'd recommend that, but you can get away without it.
1. Start by making sure the link mechanism and the carburetor throttle
valve operates smoothly without binding.
2. Attach an inductive tachometer to the No 1. cyl. (Starboard side)
spark plug high tension cord.
EMBER the idle mixture screw (when equipped and not sealed)
is NOT a periodic adjustment. If you haven't overhauled the carb or a
related component, LEAVE IT ALONE.
3. As mentioned earlier, the manufacturer does not give any information
on adjusting the idle MIXTURE for these carburetors, except that to note in
one place that a pilot screw mounted in the carburetor cover can be used to
adjust the mixture. If the carburetor or powerhead was rebuilt/replaced and
the low speed screw/needle (if equipped) was not given a preliminary
adjustment yet, do that now. (For details, please refer to the Initial Low
Speed Setting given in the Carburetor Set-Up Specifications Chart under the
Fuel System section). Rotate the pilot screw (normally located on the top of
the carb, threaded horizontally into the cover), clockwise SLOWLY and
GENTLY until the needle is lightly seated. Back the needle out exactly the
proper number of turns as determined before it was removed or using the
specifications mentioned earlier.
Water must circulate through the lower unit to the engine any time the
engine is run to prevent damage to the water pump in the lower unit.
Just a few seconds without water will damage the water pump.
4. Start the powerhead and allow it to reach normal operating
temperature.
5. With the outboard at normal operating temperature and operating in
NEUTRAL, idle speed should be about 950-1050 rpm. If however you are
operating it in GEAR, then speed should be about 900-1000 rpm. If the
motor is operating out of the specified range locate the idle speed screw, on
the side of the carburetor body. The idle speed screw is threaded downward
at an angle through a spring and bracket on the side of the carburetor
(located between the carburetor and the throttle cam assembly), so the tip
can protrude and contact the carburetor throttle lever. Turn the idle speed
screw CLOCKWISE to increase idle speed or COUNTERCLOCKWISE to
decrease speed. Make small adjustments, waiting each time for a steady idle
speed, before making the next adjustment.
6. On models with an adjustable idle mixture, if it was necessary to
adjust it earlier, it may also be necessary to tweak the screw positioning now,
with up to 114 turn from standard positioning. Turning the mixture screw
CLOCKWISE will lean out the mixture further, while turning it
COUNTERCLOCKWISE will enrichen the mixture. Make only a small
adjustment, as necessary to stabilize idle. If this adjustment is made, run the
engine at or near full throttle for a minute, then quickly drop it to idle. If the
motor coughs, pops or doesn't want to drop back down to idle, the mixture is
likely still a little too lean. Make a small adjustment, waiting 15 seconds or
more for it to stabilize, then try again. The mixture is generally considered
good once the idle stabilizes.
7. Once idle speed is properly set you can move on to checking the
Ignition Timing.
Ignition Timing
As stated earlier in this section, timing is controlled by the CDI unit based
on signals from a pulser coil. At least annually or every 200 hours of
operation you should check ignition timing to verify the system is operating
properly. The Idle Speed must be properly adjusted before checking timing.
Checking the timing at idle speed should be sufficient and can be
pertormed in a test tank or on a flush fitting, but if you want to check that the
motor is advancing properly by checking WOT timing, then you'll need to use
a test tank or launch the boat. DO NOT attempt to check the WOT timing on
a flush fitting.
1. Provide a suitable source of cooling water; a test tank, launch the
boat OR a flush fitting (unless you want to check WOT timing).
2. Attach a timing light cord to the No. 1 (Starboard) spark plug wire.
One with a built-in tach can be handy otherwise you'll want to attach a
tachometer too, especially if you are checking WOT timing and not just idle
timing.
3. Start and allow the engine to warm up to normal operating
temperature.
4. There's a timing window and pointer in the manual starterlflywheel
cover on the port side of the motor, just above the CDI unit (Ignition Module).
Point the timing light at the mark. Idle timing should be about 2' BTDC at
1000 rpm.
5. WOT timing is checked in the same basic fashion, except that you
must run the gearcase under a load (in water, with a suitable prop) to
prevent a runaway powerhead. Advance the motor to full throttle while
watching the timing marks, the timing should advance to about 27' BTDC,
but keep in mind that no maintenance recommendation was provided by the
manufacturer to check timing at WOT and this timing spec is the maximum
advance listed in the design specs for the ignition system. In other words, we
wouldn't worry if a check shows slightly less advance, as long as the motor
seems to otherwise be running properly.
If timing is not correct, the Ignition System should be checked for
faults and repairedlreplaced as necessary.
6. Shut the powerhead down, then remove the tachometer andlor timing
light.
ADJUSTMENTS
Only a couple of adjustments are possible on these motors. The following
procedures provide instructions how to check and adjust the throttle control
linkage and/or cables, Synchronize the Carburetor Throttle Valves,
checkladjust the carburetor dashpot, to checwset the idle speed, as well as
to check the ignition timing.
These motors are equipped with a digital Capacitor Discharge Ignition
(CDI) system which utilizes a CDI unitlpowerpack mounted on the
powerhead, as well as both a charge coil (in a stator) and a Crankshaft
Position Sensor (CPS, essentially a triggerlpulser coil) which are all mounted
under the flywheel. The CDI unit controls all ignition timing based on signals
from the CPS pulser coil, so no adjustments are necessary or possible.
Also, it appears that Suzuki (as well as the EPA) wants to discourage
tampering with the idle mixture on these motors. The factory service
information gives few specifications or details on initial setting of the pilot
(idle mixture) screw. Some exploded views do show a pilot needle (low
speed mixture) screw, but that's the extent of it. We've endeavored to
provide a technique for adjustment that should apply, but remember it ISN'T
a periodic adjustment and should only be performed after major component
(powerhead or carburetor) overhaul or replacement.
Throttle Linkage Adjustments
+ See Figures 178 and 179
The throttle lever rod, throttle limiterlcontrol (tillerlremote) rod and, on
remote models, the shift rod, should all not require any periodic attention,
however, should the rod or related components be replaced, an initial
adjustment is necessary to make sure it operates properly.
This procedure starts with the throttle applicable rod already disconnected
due to service.
Check the length of the rod in question compared with the specifications
following this paragraph. Measurements are taken from the centerline of a
ball connector to the centerline of the connector on the other end.
Adjustments should be made by moving BOTH ends as necessary to make
sure that approximately the same amount of rod is threaded into the
connector on each end. A locknut is provided to tighten against each
connector after they are properly positioned.
M When measuring a bent or angled rod, like the throttle limiter (tiller)
or shift rod (remote) do not try to follow the contours of the rod. Hold
the ruler off the rod and measure in straight light from connector-to-
connector.
Throttle.
Lever
Rod
Throttle
Lever
Rod Throttle
1
3.19 in. (81mm) * .----*
, 5 51 I". (i40mm) Control Rod
' 5.87 in. (143mm)
Fig. 178 Throttle control rod adjustment -
Tiller handle 25/30 hp (3-cyl) motors
Proper rod lengths are as follows:
0
Throttle lever rod (tiller and remote models) -3.19 in. (81mm)
0
Throttle limiter rod (tiller models) -9.47 in. (240.5mm)
8 Throttle control rod (remote models) -5.51 in. (140mm)
Shift rod (remote models) -5.87 in. (149mm)
Throttle Control Cable Installation/Adjustment
See Figure 180
The throttle control cables should not require any periodic attention,
however, should the cables or related components be replaced, an initial
adjustment is necessary to make sure they operate properly. Adjustment will
ensure that they allow the throttle to both open fully at Wide Open Throttle
(WOT) operation and close fully when the throttle is returned to idle.
This procedure starts with the cables already disconnected due to service.
1. Rotate the throttle control handle to the fully CLOSED throttle
position.
2, Align the matchmark on the throttle cam with the center of the throttle
lever roller, then hold it in this position.
3. Route the 2 throttle cables into the throttle drum on the powerhead
and position the locknuts loosely into the cable holder.
4. Adjust the position of the locknuts to just eliminate sag from the inner
cables, then tighten the locknuts to hold this position.
5. Rotate the throttle control handle several times from the fully closed
to the WOT position and back again.
6. Now with the throttle fully closed, make sure the matchmark on the
throttle cam is still aligned with the center of the throttle lever roller. If not,
use the locknuts to reposition the cables as necessary to achieve this again.
Synchronizing the Carburetor Throttle Valves
See Figures 181 and 182
Anytime a motor is equipped with multiple carburetors (or throttle bodies)
it is essential that they are adjusted so that each throttle valve opens and
closes at precisely the same time. Adjusting the carburetors so that they
open and close together is referred to as Synchronization or Balancing the
Carburetors/Throttle Valves.
The throttle valve position within a carburetor determines the amount of
air which flows into the intake manifold and ultimately the cylinder it feeds.
So the amount a throttle valve opens can be measured by the amount of
vacuum available at the manifold. Therefore the most common way to
Synchronize or Balance carbs is using a set of "carb sticks" (vacuum
manometers or gauges).
Carburetor synchronization SHOULD NOT BE a necessary periodic
adjustment. If the carburetors and linkage are not disturbed the settings
should hold indefinitely. However, anytime the carburetors are removed for
service, overhaul or just for access to other components they should be
Shift Rod
Fig. 180 Throttle control cable installation
and adjustment -25/30 hp (3-cyl) motors
rebalanced upon installation.
ost of this procedure takes place in Neutral and at or near idle
(except She final idle check, which can be performed separately later,
after the carbs are synched), so it can be performed on a flush fitting,
as well as in a test tank or on a launchedlrestrained boat. However,
after this procedure you'll have to checkladjust the Dashpot and even
though the dashpot itself will be adjusted with the linkage in Neutral,
when preparing it for adjustment you'll have to run it at 4000 rpm, so a
test tank or launched craft is necessary. Regardless where it takes
place be CERTAIN to make sure a source of cooling water is supplied
to the motor.
1. Before starting, visually check the carburetor throttle bodies, linkage,
fuel inlets and the air silencer pipe for signs of wear, cracks or other damage.
Replace any damaged components.
2. Connect a standard marine tachometer to the motor, as follows:
0
Yellow lead wire of the tach, to the yeilow/black CDVpowerpack unit
wire
Gray lead wire of the tach, to the positive battery terminal
Black lead wire of the tach, to the negative battery terminal
0
Make sure the tach pole selection switch is set on "12"
3. Operate the carburetor throttle valves gently by hand, feeling for any
binding, pinching or drag on the valves and link mechanism. If the assembly
does not move smoothly, correct any problems before proceeding.
4 Remove the starboard side lower engine cover for access. For
details, please refer to Engine Covers (Top and Lower Cases), earlier in this
section.
5. RIGHT underneath the pivot bolt for the throttle linkage assembly
locate the small threaded No. 3 (bottom) cylinder intake manifold plug (looks
like a Philip's head screw in most literature but it is hard to tell). Thread a
carburetor synchronizer gauge adaptor into the hole, then connect the hose
to the No. 3 tubelgauge.
6. Start the engine and allow it to slowly warm up to normal operating
temperature. Once you are certain the choke is FULLY open check the idle
speed and adjust to 850-950 rpm (in Neutral) using the No. 3 carburetor idle
adjusting screw, as necessary.
7. If you are using the Suzuki synchronizer gauge (which has adjustable
air screws on the bottom of each tube), adjust the gauge using the air screw
until the steel ball is at the tube's center line. Make sure the other tubes that
you are going to use are calibrated the same way. You can start by setting
the air screw in the same position, but it is probably a good idea to verify this
by connecting each one in turn to the No. 3 cylinder adaptor to check the
calibration.
8. Stop the engine, then remove the vacuum plugs from the intake
manifold for the No. 1 (top) and No. 2 (middle) cylinders, and thread
synchronizer adaptors into them as well. Connect tubes to both adaptors,
noting which is connected to which.
9. Restart the engine and make sure it is still fully warmed up with the
choke fully open.
When synchronizing carburetors it is important to perform all * Make sure the tach pole selection switch is set on "12"
adjustments AT IDLE speed, as this is where the greatest variances will
occur. The vacuum available at each cylinder will normally even out
much more on most motors as the rprn increases.
10. With the motor running in neutral at 850-950 rpm, compare the
readings on each of the gauges. Adjust the spring-loaded throttle valve stop
screws at each carburetor until all 3 are synchronized (the gauge readings
are identical) and the engine idles smoothly. If engine speed raises or lowers
during the adjustment, be sure to reset it to 850-950 rprn using the No. 3
(bottom) cylinder throttle screw.
11. Once the carbs are balanced, shift the gearcase into Forward and
check the in-gear idle-speed. It should be about 850 rpm.
12. Once you are finished, stop the engine, remove the sync adaptors
and reinstall the manifold plugs.
13. Check the Dashpot Adjustment.
Dashpot Adjustment
See Figures 183,184 and 185
The dashpot is used to provide a controlled deceleration when the throttle
is suddenly closed from WOT or mid-range to idle. When working properly
the dashpot will briefly hold engine speed at about 1500 rpm, then slowly
allow the motor to return to idle.
The Dashpot Adjustment must be checked again anytime carburetor
synchronization has taken place.
Even though the dashpot itself will be adjusted with the linkage in
Neutral, when preparing it for adjustment you'll have to run it at 4000
rpm, so a test tank or launched craft is necessary to prevent runaway
rprn which could damage the powerhead.
1. If not still connected from the Carburetor Synchronization procedure,
connect a standard marine tachometer to the motor, as follows:
* Yellow lead wire of the tach, to the yellow/black CDIIpowerpack unit
wire
Gray lead wire of the tach, to the positive battery terminal
Black lead wire of the tach, to the negative battery terminal
2. Start the engine and slowly warm it up to normal operating
temperature.
3. Place the motor in gear, then turn the No. 3 carburetor throttle screw
to set engine speed at 4000 rpm, counting the number of turns it takes to
reach this speed from the proper idle setting.
4. Shift the motor into Neutral and stop the motor, then remove then
remove the flywheel cover (or hand rewind starter, as applicable).
5. Operate the throttle to the fully opened (WOT) position, then return it
gradually to the idle position, all the while keeping an eye on the tip of the
dashpot rod. The tip must contact the accelerator pump lever at the same
time that the No. 3 carburetor idie adjusting screw contact? ^19throttle stop.
If the two contact points do NOT match, adjust the dashpot rod (turning the
rod CLOCKWISE moves the rod tip inward, while turning the rod
COUNTERCLOCKWISE moves the tip outward). Recheck the contact points.
6. Reset the engine idle speed by returning the No. 3 carburetor throttle
stop screw to its original position by backing it out the same number of turns
counted earlier.
7. Install the flywheel cover andlor hand rewind starter, as applicable.
8. Start the engine again and recheckladjust Idle Speed, as necessary.
9, Verify dashpot operation by shifting into forward gear and running at
various speeds between mid-range and WOT. Decelerate quickly from
various throttle positions to idie, listening for proper dashpot operation each
time the throttle is closed. Again, engine speed should hang up around 1500
rprn for a second or so each time the throttle is closed from a higher rprn
range.
Idle Speed Adjustment
See Figures 182 and 186
Idle speed itself can be adjusted with the gearcase in neutral so this
adjustment CAN occur with the motor mounted on the boat and in the water,
in a test tank or even running on a suitable flushing fitting. However, if you
need to adjust the low speed mixture (on models where that is possible)
andlor check the idie speed in gear, you'll need a test tank or to at least
launch the boat.
Balance; Air Scrow .n 3 Turn
---I ,
Fig. 181 Typical carburetor synchronization Fig. 182 Each carburetor has a throttle Fig. 183 The dashpot is mounted to the top
tool (Suzuki tool shown) valve screw of the upper carburetor
.Idte
Dashpot Adjusting
Screw
Unit
accelerator
'ump Lever
Fig. 186 The carburetor idle mixture is
Fig. 184 Dash pot adjustment -the rod must Fig. 185 . . .at the same time the No. 3 idle controlled by a pilot jet and usually a pilot
touch the accelerator pump lever. . . screw touches the throttle stop screw (though concealed on some models)
1. Before starting, visually check the carburetor throttle bodies, linkage,
fuel inlets and the air silencer pipe for signs of wear, cracks or other damage,
Replace any damaged components.
2. If not still connected from the Carburetor Synchronization and
Dashpot Adjustment procedures, connect a standard marine tachometer to
the motor, as follows:
Yellow lead wire of the tach, to the yellowlblack CDIIpowerpack unit
wire
Gray lead wire of the tach, to the positive battery terminal
Q
Black lea0 çvii'6;ii-ic iach, to the negative battery terminal
Make sure the tach pole selection switch is set on "12"
3. Start by making sure the link mechanism and the carburetor throttle
valve operates smoothly without binding. Operate the carburetor throttle
valves gently by hand, feeling for any binding, pinching or drag on the valves
and link mechanism. If the assembly does not move smoothly, correct any
problems before proceeding.
4. Start the engine and allow it to slowly warm up to normal operating
temperature. Once you are certain the choke is FULLY open check the idle
speed and make sure it is about 850-950 rpm (in Neutral). If adjustment is
necessary ONLY use the No. 3 cylinder (bottom) carburetor throttle stop
screw to make adjustments. NEVER touch the No. 1 (top) or No. 2 (middle)
screws unless you are synchronizing the carburetors.
5. As mentioned earlier, the manufacturer does not give much
information on adjusting the idle MIXTURE for these carburetors, but
specifications are available for certain models. For details, please refer to the
Carburetor Set-Up Specifications in the Fuel System section. Also, some
exploded views show a pilot screw mounted just under the carburetor cover.
We have suggested elsewhere that you should seat the old screw before
removal and count the number of turns in order to orovide an initial startina
point. If the carburetor or powerhead was rebuil~re~laced
and the low speed
screwlneedle (if equipped) was not given a preliminary adjustment yet, do
that now as follows:
a. During assembly you should have already rotated the low speed
needle (normally located along the carburetor cover-to-throttle body split line,
but threaded into the body itself), clockwise SLOWLY and GENTLY until the
needle was lightly seated, then you should have backed the needle out
exactly the proper number of turns as determined before it was removed.
b. Start the powerhead and allow it to reach normal operating
temperature.
Water must circulate through the lower unit to the engine any time the
engine is run to prevent damage to the water pump in the lower unit.
Just a few seconds without water will damage the water pump.
c. Shift the engine into forward gear and allow it to run at idle for at
least 3 minutes.
d. With the engine running at idle in forward gear, observe the running
conditions as follows:
If the engine is running rich, it will show a rough or unsteady idle.
If the engine is running lean, it will sneeze or backfire.
e. If necessary, adjust the low speed mixture screw as follows to obtain
a smooth idle:
For rich mixtures, noting the reference mark made earlier, turn the
needle 118th turn clockwise, allowing about 15 seconds between
adjustments, until the highest consistent rpm is reached.
For lean mixtures, noting the reference mark made earlier, turn the
needle 118th turn counterclockwise, allowing about 15 seconds between
adjustments, until the highest consistent rprn is reached.
f. Repeat this procedure for the remaining carburetors
g. With the engine still running at normal operating temperature and in
forward gear, adjust the idle speed screw to the center range of the Idle
Speed (RPM) in Gear listed for your motor under the Tune-up Specifications
chart (about 850 rpm).
6. Operate the outboard in forward at or near full throttle for about 3
minutes. Reduce speed suddenly to a low idle and shift into neutral. The
powerhead should continue to operate smoothly. If the powerhead pops or
stalls, the airifuel mixture is probably too lean. Rotate the low speed needle
1,'[email protected] counterclockwise, allowing about 15 seconds between
adjustments, until the powerhead responds as expected. Repeat the full
throttle test and sudden deceleration with the shift into neutral to check each
adjustment.
7. Start the engine and allow it to slowly warm up to normal operating
temperature. Once you are certain the choke is FULLY open check the idle
speed one last time and adjust to 850-950 rpm (in Neutral), as necessary.
8. Once idle speed is properly set you can move on to checking the
Ignition Timing.
Ignition Timing
@ See Figure 187
As stated earlier in this section, timing is controlled by the CDI unit based
on signals from a pulser coil. At least annually or every 200 hours of
operation you should check ignition timing to verify the system is operating
properly. The Idle Speed must be properly adjusted before checking timing.
Checking the timing at idle speed should be sufficient and can be
performed in a test tank or on a flush fitting, but if you want to check that the
motor is advancing properly by checking WOT timing, then you'll need to use
a test tank or launch the boat. DO NOT attempt to check the WOT timing on
a flush fitting.
1. Provide a suitable source of cooling water; a test tank, launch the
boat OR a flush fitting (unless you want to check WOT timing).
2. If not still connected from the Carburetor Synchronization, Dashpot
Adjustment and Idle Speed procedures, connect a standard marine
tachometer to the motor, as follows:
Yellow lead wire of the tach, to the yellowlblack CDIlpowerpack unit
wire
Gray lead wire of the tach, to the positive battery terminal
Black lead wire of the tach, to the negative battery terminal
Make sure the tach pole selection switch is set on "12
3. Attach a timing light cord to the No. 1 spark plug wire.
4. Start and allow the engine to warm up to normal operating
temperature,
5. There's a timing window and pointer in the manual starterlflywheel
cover toward the aft port side of the motor. Point the timing light at the mark.
Idle timing should be 5ÂBTDC at a speed of about 900 rpm.
6. WOT timing is checked in the same basic fashion, except that you
must run the gearcase under a load (in water, with a suitable prop) to
prevent a runaway powerhead. Advance the motor to full throttle while
watching the timing marks, the timing should advance to 31' BTDC on 25 hp
motors or 29' BTDC on 30 hp motors.
H If timing is not correct, the Ignition System should be checked for
faults and repairedlreplaced as necessary.
7. Shut the powerhead down, then remove the tachometer andlor timing
light.
Fig. 187 Use the pointer and window on the manual starterlflywheel
cover to check timing
ADJUSTMENTS
DERATE
One of the great benefits of a fuel injected motor is that most of the
functions that are mechanical on a carbureted motor (and therefore subject
to wear and adjustment) are electronically monitored and adjusted to
maximize engine performance. The fuel and ignition systems are all but
completely controlled by the Engine Control Unit (ECU) on these models.
The ECU is a computer control module that accepts input from various
sensors mounted around the engine and makes both ignition timing and fuel
mapping decisions based on those inputs.
Ignition timing can be checked using a timing light, but there are no
adjustments. Should it be found out of specification, the electronic engine
control system should be checked for problems. Of course, don't get into the
trap of assuming every problem that arises is electronic. Although the ECU
does an incredible job of regulating engine operation on these motors, it is
subject to the same mechanical limitations of any motor. Mechanical
problems will often manifest themselves in symptoms of the electronic
engine control system and can lead frustration during troubleshooting if you
concentrate only on the electronics.
There is one mechanical setting that should be checked and adjusted
annually (or after every 200 hours of operation). The idle air by-pass air
screw is a mechanically adjustable passage that provides air to the motor
beyond what is controlled by the ECU. This system is used to set a base idle
speed by allowing a certain amount of air to by-pass the ECU controls.
Although the manufacturer recommends annual checking of this setting,
don't get too excited yet, these motors have proven to be very reliable when
maintained properly and this setting does not require adjustment often.
Checking Idle Speed (Idle By-pass Air Screw Adjustment)
See Figures 188 and 189
Idle speed on the 40150 hp EFI motors is controlled electronically through
the Idle Air Control (IAC) valve. The valve is a stepper motor that can be
used by the ECU to allow greater amounts of air into the engine in order to
produce fast idle (for quick engine warm-up). Once the engine reaches
normal operating temperature, the IAC valve usually closes and all idle air is
supplied through the IAC bypass. Therefore, during warm engine operation,
the idle by-pass air screw adjustment determines the amount of air
circumventing the otherwise closed IAC valve.
Perform the warm engine idle speed and by-pass air screw check and
adjustment annually or during every other tune-up (every 200 hours of
operation). Remember that you must make sure that idle speed is properly
adjusted before checking Ignition Timing on these models.
H Before checking the idle speed, make sure the throttle linkage
moves smoothly without binding or resistance.
As long as all adjustments are to take place at or near idle, they can be
performed on a flush fitting, as well as with a test tank or on a launched craft.
1. Connect a shop tachometer following the manufacturer's instructions
and provide a cooling water source. Because this is a coil over plug direct
ignition system you will likely have to remove the bolt securing the No. 1 (top
cylinder) ignition coil, and pull the coil off the spark plug, then install a special
high tension cord with plug cap adaptor (#09930-88720) or equivalent
between the plug and coil in order to get a tachometer signal.
The high tension cord adapter can easily be made from a spare
spark plug wire. Basically it's just a way to remove the direct ignition
coil and place a wire between its spark plug terminal and the actual
spark plug so you can keep the circuit complete and still install an
inductive tachometer pickup.
2. Place the gear selector in neutral, then start the engine and allow it
to run until it fully reaches normal operating temperature.
3. Place the throttle control in the idle position and keep the gear
selector in neutral. The motor should idle at a speed of 800-900 rprn. If it
does, you're done. If idle is out of specification and you're SURE the motor is
fully warmed, then continue with the procedure in order to adjust the idle
speed.
4. Disconnect the IAC valve hose from the air silencer, then block air
flow by pinching or plugging the hose (using a golf tee, plastic plug or piece
of tape, heck, you CAN just put your finger over it if need be).
5. If used, remove the rubber plug or cap from the idle air by-pass
screw opening on top boss of the throttle body, just below the overhang of
the intake manifold.
6. If idle speed requires adjustment, slowly turn the idle speed screw
until the engine reaches 800 rprn. Turning the screw clockwise reduces air
flow (decreases rpm), while turning the counterclockwise increases air flow
(increases rprn).
7. Unblock the IAC valve hose (allowing air into the valve) and recheck
the idle speed, it should be stable in the 800-900 rpm range. Keep in mind
that the idling or trolling speed is controlled by the IAC system and IF the
engine speed does not return to specification when the hose is unblocked,
then the IAC passage (including the hose or silencer itself) may be clogged
(or not operating correctly from an electrical standpoint).
Because the idle speed is ECU controlled through the IAC valve,
neutral or trollinglin gear speed should be the same.
8. If used, reinstall the rubber plug or cap to the idle air screw bore.
9. If desired, check the ignition timing at this point.
10. When finished, stop the engine and remove the tachometer.
Checking Ignition Timing
Â¥ See Figure 190
The ECU controls both the fuel and ignition systems. The ECU adjusts
ignition timing to optimize engine operation based primarily on input from the
Manifold Absolute Pressure (MAP) and Crankshaft Position (CKP) sensors.
However, the ECU also uses input from the Camshaft Position (CMP)
sensor, Closed Throttle Position (CTP) switch, Cylinder Temperature (CT)
sensor and, of course, the ignition switch itself.
At initial start-up (while cranking), ail ignition coils fire simultaneously each
time a piston reaches 7' BTDC. Once engine speed rises above a certain
point (it used to be 440 rpm on these motors), the ECU will begin ignition
timing based on programmed mapping.
Fig. 188 Disconnect and block the IAC valve Fig. 189 Then remove the cap and adjust Fig. 190 Check ignition timing through the
hose so no air can pass the by-pass air screw flywheel cover
I I
After the engine starts and runs at fast idle, ignition timing will remain
fixed at 9' BTDC with the motor running in neutral above 1200 rpm.
During idlingltrolling, the ECU will vary ignition timing to help stabilize idle
speed. The ECU will control ignition timing anywhere from IOATDC to 17'
BTDC with engine speeds between 800-900 rpm.
For normal operation including acceleration, deceleration and engine
speeds in gear, above idle, the ECU will follow various ignition timing
mapping programs. The ECU will maintain timing between approximately 0-
27' BTDC on 40 hp motors or 0-24' BTDC for 50 hp motors (some data
suggests that the timing range was more like 0-25 BTDC for some 2002 and
2003 models).
Anytime the throttle valve is closed suddenly (as determined by the CTP
switch suddenly turning on), ignition timing change is delayed for a
programmed duration in order to help prevent stumble or stalling.
As long as you are not checking WOT timing, this ignition timing check
can be performed on a flush fitting, as well as with a test tank or on a
launched craft. However, if you wish to check timing from mid-range to WOT,
you'll need to place a load on the propeller (i.e. with a test tank or with a
launched craft) to prevent possible powerhead damage.
To check ignition timing:
1. Connect the timing light according to the tool manufacturer's
instructions. Because this is a coil over plug direct ignition system you will
likely have to remove the bolt securing the No. 1 (top cylinder) ignition coil,
and pull the coil off the spark plug, then install a special high tension cord
with plug cap adaptor (#09930-88720) or equivalent between the plug and
coil in order to get a tachometer signal.
2. Run the engine either at idle in neutral using a cooling water supply
or mounted on a boatlin a test tank and under the various conditions noted
above.
Timing marks should be on the flywheel, while the pointer is
contained in a window on the flywheel cover, at the top of the motor.
3. If proper fixed timing is noted during fast idle operation, the ECU is
properly controlling engine timing. Generally you should expect to see timing
at about 7' BTDC @ 1000 rpm, or 9' BTDC @ > 1200 rpm (in neutral).
ADJUSTMENTS
One of the great benefits of a fuel injected motor is that most of the
functions that are mechanical on a carbureted motor (and therefore subject
to wear and adjustment) are electronically monitored and adjusted to
maximize engine performance. The fuel and ignition systems are all but
completely controlled by the Engine Control Unit (ECU) on these models.
The ECU is a computer control module that accepts input from various
sensors mounted around the engine and makes both ignition timing and fuel
mapping decisions based on those inputs.
Ignition timing can be checked using a timing light, but there are no
adjustments. Should it be found out of specification, the electronic engine
contro! system should be checked for problems. Of course, don't get into the
trap of assuming every problem that arises is electronic. Although the ECU
does an incredible job of regulating engine operation on these motors, it is
subject to the same mechanical limitations of any motor. Mechanical
problems will often manifest themselves in symptoms of the electronic
engine control system and can lead frustration during troubleshooting if you
concentrate only on the electronics.
There is one mechanical setting that should be checked and adjusted
annually (or after every 200 hours of operation). The idle air bypass air
screw is a mechanically adjustable passage that provides air to the motor
beyond what is controlled by the ECU. This system is used to set a base idle
speed by allowing a certain amount of air to by-pass the ECU controls.
Although the manufacturer recommends annual checking of this setting,
don't get too excited yet, these motors have proven to be very reliable when
maintained properly and this setting does not require adjustment often.
Checking Idle Speed (Idle By-pass Air Screw Adjustment)
See Figure 191
Idle speed on the 60170 hp EFI motors is controlled electronically through
the Idle Air Control (IAC) valve, which protrudes from the side of the intake at
the front, center of the motor. The valve is a stepper motor that can be used
by the ECU to allow greater amounts of air into the engine in order to
produce fast idle (for quick engine warm-up). Once the engine reaches
normal operating temperature, the IAC valve usually closes and all idle air is
supplied through the IAC by-pass (a small brass inlet on the intake manifold
that looks like a hose connector).
During warm operation, the idle bypass air screw adjustment determines
the amount of air circumventing the closed IAC valve. The screw, located in
the intake manifold downstream of the throttle body and adjacent to the
brass air inlet, is set at the factory and sealed to prevent unnecessary
tampering or adjustment.
Perform the warm engine idle speed and by-pass air screw check and
adjustment annually or during every other tune-up (every 200 hours of
operation). Remember that you must make sure that idle speed is properly
adjusted before checking Ignition Timing on these models.
M Before checking the idle speed, make sure the throttle linkage
moves smoothly without binding or resistance.
1. Connect a shop tachometer following the manufacturer's instructions
and provide a cooling water source.
2. Shift the gearcase into neutral, then start the engine and allow it to
run until it reaches normal operating temperature and idle has fully stabilized.
3. With the engine still running in neutral, place the throttle control in the
idle position. The engine should idle at a speed of about 650-750 rpm. If it
does. vou're done. If idle is out of s~ecification and vou're SURE the motor is
fully warmed, then continue with the procedure in order to adjust the idle
speed, but note the procedure varies slightly with year as the ECU
calibration changed.
4 On 2002 and earlier models, proceed as follows:
a. Stop airflow from the IAC valve by disconnecting the hose (connect
to the throttle body at the front of the motor a little above the by-pass screw)
and cappinglpinchinglholding the hose closed.
b. If not done already, remove the cap from the by-pass screw bore,
then use the screw to adjust the speed to approximately 600 rpm. Turning
the screw CLOCKWISE should LOWER engine speed, while turning the
screw COUNTERCLOCKWISE should raise engine speed.
c. Release the hose and recheck the idle speed, it should stabilize at
650-750 rpm. Remember the ECU will use the IAC valve to self-adjust the
trolling and idle speed to this setting.
If engine speed does not return and stabilize at specification then
check the IAC passage (including the IAC hose and the silencer) for
clogs. If no clogs are found, IAC operation is questionable.
Troubleshoot the system further. For more details refer to the Fuel
Injection information in the Fuel System section.
1 Fig. 191 By-pass screw and IAC valve hose locations -60170hp
motors
5. On 2003 and later models, proceed as follows:
a. Check that the Closed Throttle Position (CTP) switch is ON. Meaning
either use a scan toolldiagnostic software, if available, or use a DVOM. A
DVOM can be used either to carefully backprobe the connectors of the circuit
to check for voltage or it can be used with the switch harness disconnected
to check resistance directly across the switch terminals. In either case,
you're looking for a sign that the circuit is closed, meaning there IS voltage
OR there is littlelno resistance.
H Alternately, you may be able to check the CTP switch manually with
a DVOM while the motor is not running and the switch harness is
disconnected, then note the linkage position andlor look for other
physical signs (does the switch click at all when actuated) that the
switch is on.
6. Set the IAC valve duty to a constant 22.5% by turning the by-pass air
screw until engine speed is at 1000 rpm or more and allow the motor to hold
that speed for at least 10 seconds. After 10 seconds a warning buzzer
should sound notifying that the IAC duty is in "fixed mode."As long as the
motor remains in this mode the buzzer will sound for 0.5 seconds with
intervals of 3 seconds. This fixed mode (complete with buzzer) should last
for 5 minutes before automatically canceling. You have that long to finish
adjustments, or you have to start again. If you wish to manually cancel the
"fixed mode" operation before that time, simply open the throttle momentarily
to turn the CTP switch off.
H Turning the idle air by-pass screw COUNTERCLOCKWISE will
INCREASE engine speed, while turning the screw CLOCKWISE will
DECREASE engine speed.
7. While the motor runs in IAC "fixed mode" adjust the engine speed to
650-750 rpm using the by-pass screw. Once adjusted, open the throttle valve
to turn the CTP switch off, canceling the "fixed mode" operation.
8. Close the throttle and recheck engine idle speed. It should no remain
stable at 650-750 rpm. If the engine speed does not return to specification
properly then there may be a problem with the IAC system (electrical, or
mechanical such as a clogged passage or hose, and we'd suggest checking
the mechanical possibilities first).
H Because the idle speed is ECU controlled through the IAC valve,
neutral or trolling/in gear speed should be the same.
9. If used, reinstall the plug or cap to the idle air screw plug.
10. If desired, check the ignition timing at this point.
11. When finished, stop the engine and remove the tachometer.
Checking Ignition Timing
See Figure 192
The ECU controls both the fuel and ignition systems. The ECU adjusts
ignition timing to optimize engine operation based primarily on input from the
Manifold Absolute Pressure (MAP) and Crankshaft Position (CKP) sensors.
However, the ECU also uses input from the Closed Throttle Position (CTP)
switch, Cylinder Temperature (CT) sensor and, of course, the ignition switch
itself.
At initial start-up (while cranking), all ignition coils fire simultaneously each
time a piston reaches 5' BTDC. Once engine speed rises above a
predetermined point (which used to be 440 rpm on these motors), the ECU
begin ignition timing based on programmed mapping.
After the engine starts and runs at fast idle, ignition timing will remain
fixed. The ECU will fix timing 5" BTDC with the motor running in neutral
above 1000 rpm.
During idlingltrolling, the ECU will vary ignition timing to help stabilize idle
speed. The ECU will maintain ignition timing at 4-16Â BTDC with a stable
engine speed of about 700 rpm (650-750 rpm).
For normal operation including acceleration, deceleration and engine
speeds in gear, above idle, the ECU will follow various ignition timing
mapping programs. The ECU will maintain timing between 10-33' BTDC for
60 hp motors and 10-29' BTDC for 70 hp motors.
Anytime the throttle valve is closed suddenly (as determined by the CTP
switch suddenly turning on), ignition timing change is delayed for a
programmed duration in order to help prevent stumble or stalling.
As long as you are not checking WOT timing, this ignition timing check
can be performed on a flush fitting, as well as with a test tank or on a
launched craft. However, if you wish to check timing from mid-range to WOT,
you'll need to place a load on the propeller (i.e. with a test tank or with a
launched craft) to prevent possible powerhead damage.
To check ignition timing:
1. Connect the timing light according to the tool manufacturer's
instructions.
2. Run the engine either at idle in neutral using a cooling water supply
or mounted on a boaffin a test tank and under the various conditions noted
above.
B Timing marks can be found along with a pointer on the flywheel
cover at the top of the motor.
3. If proper fixed timing is noted during fast idle operation, the ECU is
controlling engine timing. Generally you should expect to see timing at about
10' BTDC @ 1000 rpm.
ADJUSTMENTS
One of the great benefits of a fuel injected motor is that most of the
functions that are mechanical on a carbureted motor (and therefore subject
to wear and adjustment) are electronically monitored and adjusted to
maximize engine performance. The fuel and ignition systems are all but
completely controlled by the Engine Control Unit (ECU) on these models.
The ECU is a computer control module that accepts input from various
sensors mounted around the engine and makes both ignition timing and fuel
mapping decisions based on those inputs.
Ignition timing can be checked using a timing light, but there are no
adjustments. Should it be found out of specification, the electronic engine
control system should be checked for problems. Of course, don't get into the
trap of assuming every problem that arises is electronic. Although the ECU
does an incredible job of regulating engine operation on these motors, it is
subject to the same mechanical limitations of any motor. Mechanical
problems will often manifest themselves in symptoms of the electronic
engine control system and can lead frustration during troubleshooting if you
concentrate only on the electronics.
There is one mechanical setting that should be checked and adjusted
annually (or after every 200 hours of operation). The idle air by-pass air
screw is a mechanically adjustable passage that provides air to the motor
beyond what is controlled by the ECU. This system is used to set a base idle
speed by allowing a certain amount of air to by-pass the ECU controls.
Although the manufacturer recommends annual checking of this setting,
don't get too excited yet, these motors have proven to be very reliable when
maintained properly and this setting does not require adjustment often.
Fig. 192 Ignition timing window -60170hp motors
Checking Idle Speed (Idle By-pass Air Screw Adjustment)
See Figures 193 and 194
Idle speed on the 90/115/140 hp EFI motors is controlled electronically
through the Idle Air Control (IAC) valve, mounted at the top front of the intake
manifoldhhrottle body assembly. The valve is a stepper motor that can be
used by the ECU to allow greater amounts of air into the engine in order to
produce fast idle (for quick engine warm-up). Once the engine reaches
normal operating temperature, the IAC valve usually closes and all idle air is
supplied through the IAC by-pass.
During warm operation, the idle by-pass air screw adjustment determines
the amount of air circumventing the closed IAC valve. The screw, located in
the intake manifoldlthrottle body assembly, is positioned horizontally at the
front of the motor, about halfway down the silver manifold assembly. It is set
at the factory and sealed with a cap to prevent unnecessary tampering or
adjustment.
Perform the warm engine idle speed and by-pass air screw check and
adjustment annually or during every other tune-up (every 200 hours of
operation). Remember that you must make sure that idle speed is properly
adjusted before checking Ignition Timing on these models.
H Before checking the idle speed, make sure the throttle linkage
moves smoothly without binding or resistance.
1. Connect a shop tachometer following the manufacturer's instructions
and provide a cooling water source.
2. Shift the gearcase into neutral, then start the engine and allow it to
run until it reaches normal operating temperature and idle has fully stabilized.
3. With the engine still running in neutral, place the throttle control in the
idle position. The engine should idle at a speed of about 600-650 rpm for
901115 hp motors or 650-750 rprn for 140 hp motors. If it does, you're done.
If idle is out of specification and you're SURE the motor is fully warmed, then
continue with the procedure in order to adjust the idle speed.
4. Check that the Closed Throttle Position (CTP) switch is ON.
(Meaning either use a scan toolldiagnostic software, if available, or use a
DVOM. A DVOM can be used either to carefully backprobe the connectors of
the circuit to check for voltage or it can be used with the switch harness
disconnected to check resistance directly across the switch terminals. In
either case, you're looking for a sign that the circuit is closed, meaning there
IS voltage OR there is littlelno resistance.)
Alternately, you may be able to check the CTP switch manually with
a DVOM while the motor is not running and the switch harness is
disconnected, then note the linkage position andlor look for other
physical signs (does the switch click at all when actuated) that the
switch is on.
5. Set the IAC valve duty to a constant 15% by turning the by-pass air
screw until engine speed is at 1000 rprn or more and allow the motor to hold
that speed for at least 10 seconds. After 10 seconds a warning buzzer
should sound notifying that the IAC duty is in "fixed mode." As long as the
motor remains in this mode the buzzer will sound for 0.5 seconds with
intervals of 3 seconds. This fixed mode (complete with buzzer) should last
for 5 minutes before automatically canceling. You have that long to finish
adjustments, or you have to start again. If you wish to manually cancel the
"fixed mode" operation before that time, simply open the throttle momentarily
to turn the CTP switch off.
B Turning the idle air bypass screw COUNTERCLOCKWISE will
INCREASE engine speed, while turning the screw CLOCKWISE will
DECREASE engine speed.
6. While the motor runs in IAC "fixed mode" adjust the engine speed to
600-650 rpm for 901115 hp motors or 650-750 rprn for 140 hp motors using
the by-pass screw. Once adjusted, open the throttle valve to turn the CTP
switch off, canceling the "fixed mode" operation.
7. Close the throttle and recheck engine idle speed. It should now
remain stable at 600-650 rpm (901115 hp) or 650-750 rpm (140 hp), as
applicable. If the engine speed does not return to specification properly then
there may be a problem with the IAC system (electrical, or mechanical such
as a clogged passage or hose, and we'd suggest checking the mechanical
possibilities first).
H Because the idle speed is ECU controlled through the IAC valve,
neutral or trollinglin gear speed should be the same.
8. If used, reinstall the plug or cap to the idle air screw plug.
9. If desired, check the ignition timing at this point.
10. When finished, stop the engine and remove the tachometer.
Checking Ignition Timing
ç See Figure 195
The ECU controls both the fuel and ignition systems. The ECU adjusts
ignition timing to optimize engine operation based primarily on input from the
Manifold Absolute Pressure (MAP) and Crankshaft Position (CKP) sensors.
However, the ECU also uses input from the Closed Throttle Position (CTP)
switch, Cylinder Temperature (CT) sensor and, of course, the ignition switch
itself.
At initial start-up (while cranking), all ignition coils fire simultaneously each
time a piston reaches 5' Before Top Dead Center (BTDC). Once engine
speed rises above a predetermined point, the ECU will begin ignition timing
based on programmed mapping.
After the engine starts and runs at fast idle, ignition timing will remain
fixed. The ECU will fix timing 8' BTDC with the motor running in neutral
above 900 rpm.
During idlingltrolling, the ECU will vary ignition timing to help stabilize idle
speed. The ECU will maintain ignition timing at 3-13' BTDC with a stable
engine speed of about 625 rpm (600-625 rpm) for 90111 5 hp motors or 5-1 5'
BTDC with a stable engine speed of about 700 rprn (650-750 rpm) for 140
hp motors.
For normal operation including acceleration, deceleration and engine
speeds in gear, above idle, the ECU will follow various ignition timing
mapping programs. The ECU will maintain timing between 1-44' BTDC for
90 hp motors, 3-44' BTDC for 115 hp motors, and 5-45' BTDC for 140 hp
motors.
Anytime the throttle valve is closed suddenly (as determined by the CTP
switch suddenly turning on), ignition timing change is delayed for a
programmed duration in order to help prevent stumble or stalling.
As long as you are not checking WOT timing, this ignition timing check
can be performed on a flush fitting, as well as with a test tank or on a
launched craft. However, if you wish to check timing from mid-range to WOT,
you'll need to place a load on the propeller (i.e. with a test tank or with a
launched craft) to prevent possible powerhead damage.
Fig, 193 The IAC Valve is mounted at the Fig. 194 Air Bypass Screw locations -Fig. 195 Ignition timing window -90/115/140
top corner of the intake 90/115/140 hp motors hp motors
To check ignition timing:
1. Connect the timing light according to the tool manufacturer's
instructions.
2. Run the engine either at idle in neutral using a cooling water supply
or mounted on a boatfin a test tank and under the various conditions noted
above.
Timing marks can be found along with a pointer on the flywheel
cover at the top of the motor.
3. If proper fixed timing is noted during fast idle operation, the ECU is
controlling engine timing. Generally you should expect to see timing at about
8' BTDC @ 1000 rpm.
ADJUSTMENTS
One of the great benefits of a fuel injected motor is that most of the
functions that are mechanical on a carbureted motor (and therefore subject
to wear and adjustment) are electronically monitored and adjusted to
maximize engine performance. The fuel and ignition systems are all but
completely controlled by the Engine Control Unit (ECU) on these models.
The ECU is a computer control module that accepts input from various
sensors mounted around the engine and makes both ignition timing and fuel
mapping decisions based on those inputs.
Ignition timing can be checked using a timing light, but there are no
adjustments. Should it be found out of specification, the electronic engine
control system should be checked for problems. Of course, don't get into the
trap of assuming every problem that arises is electronic. Although the ECU
does an incredible job of regulating engine operation on these motors, it is
subject to the same mechanical limitations of any motor. Mechanical
problems will often manifest themselves in symptoms of the electronic
engine control system and can lead frustration during troubleshooting if you
concentrate only on the electronics.
There is one mechanical setting that should be checked and adjusted
annually (or after every 200 hours of operation). The idle air by-pass air
screw is a mechanically adjustable passage that provides air to the motor
beyond what is controlled by the ECU. This system is used to set a base idle
speed by allowing a certain amount of air to by-pass the ECU controls,
Although the manufacturer recommends annual checking of this setting,
don't get too excited yet, these motors have proven to be very reliable when
maintained properly and this setting does not require adjustment often.
Checking Idle Speed (Idle By-pass Air Screw Adjustment) OE
Idle speed on these EFI motors is controlled electronically through the Idle
Air Control (IAC) valve, mounted at the top middle of the powerhead on the
starboard side (at the top of the intake manifold between the throttle body
and the engine lifting bracket). The valve is a stepper motor that can be used
by the ECU to allow greater amounts of air into the engine in order to
produce fast idle (for quick engine warm-up). Once the engine reaches
normal operating temperature, the IAC valve usually closes and all idle air is
supplied through the IAC by-pass.
During warm operation, the idle by-pass air screw adjustment determines
the amount of air circumventing the closed IAC valve. The screw is located
on the lower, outer, front corner of the throttle body right by the electrical
connector for the Throttle Position Sensor (TPS). It is set at the factory and
sometimes sealed with a cap to prevent unnecessary tampering or
adjustment (though since it is normally covered by the fuel hose guard on
these models the cap may not be installed).
Perform the warm enoine idle speed and bv-pass air screw check and
adjustment annually or during every other tune-up (every 200 hours of
operation). Remember that you must make sure that idle speed is properlv
.. .
adjusted before checking ignition Timing on these models.'
Before checking the idle speed, make sure the throttle linkage
moves smoothly without binding or resistance.
1. Connect a shop tachometer following the manufacturer's instructions
and provide a cooling water source. Because this is a coil over plug direct
ignition system you will likely have to remove the bolt securing the No. 1 (top
cylinder) ignition coil, and pull the coil off the spark plug, then install a special
high tension cord with plug cap adaptor (#09930-89350) or equivalent
between the plug and coil in order to get a tachometer signal.
B The high tension cord adapter can easily be made from a spare
spark plug wire. Basically it's just a way to remove the direct ignition
coil and place a wire between its spark plug terminal and the actual
spark plug so you can keep the circuit complete and still install an
inductive tachometer pickup.
2. Provide a suitable cooling water source.
3. Shift the gearcase into neutral, then start the engine and allow it to
run until it reaches normal operating temperature and idle has fully stabilized.
4. With the engine still running in neutral, place the throttle control in the
idle position. The engine should idle at a speed of about 600-700 rpm. If it
does, you're done. If idle is out of specification and you're SURE the motor is
fully warmed, then continue with the procedure in order to adjust the idle
speed.
5. Remove the 3 bolts that secure the fuel hose guard on starboard
side of the motor, right above the intake manifold. There is one bolt at either
end of the cover and one toward the middle on the top, at the engine lifting
bracket. Remove the cover for access.
6. If not done already, shift into Neutral and fully close the throttle,
which should cause the TPS to send a "full close throttle signal" to the ECU.
According to Suzuki Switching from ON to START 5 times in 10
seconds in the next step should be done with the engine ALREADY
RUNNING at idle. We're assuming the powerhead has a safety circuit
which will keep the electric starter from attempting to engage during
this portion of the procedure or that Suzuki expects key motion to be
fast enough to keep it from engaging.
7. Set the IAC valve duty to a constant 10% by turning the ignition key
from ON to START (back and forth) 5 times within 10 seconds. At this time
the warning buzzer should sound notifying that the IAC duty is in "fixed
mode." As long as the motor remains in this mode the buzzer will sound for
0.5 seconds with intervals of 3 seconds. This fixed mode (complete with
buzzer) should last for 5 minutes before automatically canceling. You have
that long to finish adjustments, or you have to start again. If you wish to
manually cancel the "fixed mode" operation before that time, simply open the
throttle momentarily.
Turning the idle air by-pass screw COUNTERCLOCKWISE will
INCREASE engine speed, while turning the screw CLOCKWISE will
DECREASE engine speed.
8. While the motor runs in IAC "fixed mode" adjust the engine speed to
600-700 rpm using the by-pass screw. Once adjusted, open the throttle valve
to cancel the "fixed mode" operation.
Fixed mode operation will cancel anytime the motor is shifted to
Forward or Reverse, or the throttle is opened (which changes the TPS
full close throttle signal from ON to OFF).
9. Close the throttle and recheck engine idle speed. It should now
remain stable at 600-700 rpm. If the engine speed does not return to
specification properly then there may be a problem with the IAC system
(electrical, or mechanical such as a clogged passage and we'd suggest
checking the mechanical possibilities first).
Because the idle speed is ECU controlled through the IAC valve,
neutral or trollinglin gear speed should be the same.
10. If used, reinstall the plug or cap to the idle air screw plug.
11. If desired, check the ignition timing at this point.
12. When finished, stop the engine and remove the tachometer.
Checking Ignition Timing
The ECU controls both the fuel and ignition systems. The ECU adjusts
ignition timing to optimize engine operation based primarily on input from the
Manifold Absolute Pressure (MAP) and Crankshaft Position (CKP) sensors.
However, the ECU also uses input from the Shift Position (SP) sensor,
Throttle Position Sensor (TPS), Cylinder Temperature (CT) sensor and, of
course, the ignition switch itself.
At initial start-up (while cranking), all ignition coils fire simultaneously each
time a piston reaches 5' BTDC. Once engine speed rises above a
predetermined point, the ECU will begin ignition timing based on
programmed mapping.
After the engine starts, during idlingltrolling, the ECU it,'!,',a/y ignition
timing to help stabilize idle speed. The ECU will maintain ignition timing at 0-
10' BTDC with a stable engine speed of about 600-700 rpm.
For normal operation including acceleration, deceleration and engine
speeds in gear, above idle, the ECU will follow various ignition timing
mapping programs. The ECU will maintain timing between 5-26' BTDC.
As long as you are not checking WOT timing, this ignition timing check
can be performed on a flush fitting, as well as with a test tank or on a
launched craft. However, if you wish to check timing from mid-range to WOT,
you'll need to place a load on the propeller (i.e. with a test tank or with a
launched craft) to prevent possible powerhead damage.
To check ignition timing:
1. Connect the timing light according to the tool manufacturer's
instructions or the tips noted earlier in this section under the procedure for
Checking Idle Speed (Idle By-pass Air Screw Adjustment).
2. Run the engine either at idle in neutral using a cooling water supply
or mounted on a boatiin a test tank and under the various conditions noted
above.
Timing marks can be found along with a pointer on the flywheel
cover at the top of the motor.
3, If proper fixed timing is noted during fast idle operation, the ECU is
controlling engine timing. Generally you should expect to see timing at about
10' BTDC @ 1000 rpm.
ADJUSTMENTS
DERATE
One of the great benefits of a fuel injected motor is that most of the
functions that are mechanical on a carbureted motor (and therefore subiect
'
to wear and adjustment) are electronically monitored and adjusted to
maximize engine performance. The fuel and ignition systems are all but
completely controlled by the Engine Control Unit (ECU) on these models.
The ECU is a computer control module that accepts input from various
sensors mounted around the engine and makes both ignition timing and fuel
mapping decisions based on those inputs.
Ignition timing can be checked using a timing light, but there are no
adjustments. Should it be found out of specification, the electronic engine
control system should be checked for problems. Of course, don't get into the
trap of assuming every problem that arises is electronic. Althoughthe ECU
does an incredible iob of reoulatina enaine operation on these motors, it is
subiect to the same mechanical limitations of any motor. Mechanical
problems will often manifest themselves in symptoms of the electronic
engine control system and can lead frustration during troubleshooting if you
concentrate only on the electronics.
There is one mechanical setting that should be checked and adjusted
annually (or after every 200 hours of operation). The idle air by-pass air
screw is a mechanically adjustable passage that provides air to the motor
beyond what is controlled by the ECU. This system is used to set a base idle
speed by allowing a certain amount of air to by-pass the ECU controls.
Although the manufacturer recommends annual checking of this setting,
don't get too excited yet, these motors have proven to be very reliable when
maintained properly and this setting does not require adjustment often.
Checking Idle Speed (Idle By-pass Air Screw Adjustment) OEM
Idle speed on the 20012251250 hp EF1 motors is controlled electronically
through the Idle Air Control (IAC) valve, mounted at the top of the intake
manifold where the air intake silencer/flywheel cover connects to the throttle
body. The valve is a stepper motor that can be used by the ECU to allow
greater amounts of air into the engine in order to produce fast idle (for quick
engine warm-up). Once the engine reaches normal operating temperature,
the IAC valve usually closes and all idle air is supplied through the IAC by-
pass.
During warm operation, the idle by-pass air screw adjustment determines
the amount of air circumventing the closed IAC valve. The screw, located in
the intake manifoldlthrottle body assembly, is positioned horizontally facing
toward the starboard side of the motor, not an inch or so down below the air
intake'flywheel cover. It is set at the factory and sealed with a cap to prevent
unnecessary tampering or adjustment.
Perform the warm engine idle speed and by-pass air screw check and
adjustment annually or during every other tune-up (every 200 hours of
operation). Remember that you must make sure that idle speed is properly
adjusted before checking Ignition Timing on these models.
B Before checking the idle speed, make sure the throttle linkage
moves smoothly without binding or resistance. Also, be sure to check
the PCV valve and hose for blockages, as they would affect idle speed.
1. Connect a shop tachometer following the manufacturer's instructions
and provide a cooling water source. Because this is a coil over plug direct
ignition system you may have to remove the bolt securing the No. 1 (top
cylinder) ignition coil, and pull the coil off the spark plug, then install a special
high tension cord with plug cap adaptor (#5035748) or equivalent between
the plug and coil in order to get a tachometer signal.
2. Shift the gearcase into neutral, then start the engine and allow it to
run until it reaches normal operating temperature and idle has fully stabilized.
3. With the engine still running in neutral, place the throttle control in the
idle position. The engine should idle at a speed of about 600-700 rpm. If it
does, you're done. If idle is out of specification and you're SURE the motor is
fully warmed, then continue with the procedure in order to adjust the idle
speed.
4. Fully close the throttle to make sure the ECM is getting a fully closed
signal from the Throttle Position Sensor (TPS).
5. Set the IAC valve duty to a constant 30% by turning the ignition
switch from ON to START 5 times within 10 seconds while the engine is
running at idle speed. A warning buzzer should sound notifying that the IAC
duty is in "fixed mode." As long as the motor remains in this mode the buzzer
will sound for at intervals of 3 seconds. This fixed mode (complete with
buzzer) should last for 5 minutes before automatically canceling. You have
that long to finish adjustments, or you have to start again. If you wish to
manually cancel the "fixed mode" operation before that time, simply open the
throttle or shift the outboard momentarily and the ECM will cancel the "fixed
duty mode.
B Turning the idle air by-pass screw COUNTERCLOCKWISE will
INCREASE engine speed, while turning the screw CLOCKWISE will
DECREASE engine speed.
6. While the motor runs in IAC "fixed mode" adjust the engine speed to
600-700 rpm using the by-pass screw. Once adjusted, open the throttle valve
or shift the outboard in order to cancel the "fixed mode" operation.
7. Close the throttle and recheck engine idle speed. It should no remain
stable at 600-700 rpm. If the engine speed does not return to specification
properly then there may be a problem with the IAC system (electrical, or
mechanical such as a clogged passage, and we'd suggest checking the
mechanical possibilities first).
ecause the idle speed is ECU controlled through the IAC valve,
neutral or trollinglin gear speed should be the same.
8. If used, reinstall the plug or cap to the idle air screw plug.
9. If desired, check the ignition timing at this point.
10. When finished, stop the engine and remove the tachometer.
Checking Ignition Timing
See Figure 196
The ECU controls both the fuel and ignition systems. The ECU adjusts
ignition timing to optimize engine operation based primarily on input from the
Manifold Absolute Pressure (MAP) and Crankshaft Position (CKP) sensors.
However, the ECU also uses input from the Throttle Position Sensor (TPS),
Cylinder Temperature (CT) sensor, Shift Position (SP) sensor and, of course,
the ignition switch itself.
At initial start-up (while cranking), timing is fixed at 5' BTDC for the
starboard bank or 0' BTDC for the port bank. The fixed timing strategy is
used until the engine starts. Once engine speed rises above a
predetermined point, the ECU will begin ignition timing based on
programmed mapping.
During idleitrolling operation the ECU will vary ignition timing to help
stabilize idle speed. The ECU will maintain ignition timing anywhere between
5OATDC and 5' BTDC with a stable engine speed of about 650 rprn (600-
700 rpm).
For normal operation including acceleration, deceleration and engine
speeds in gear, above idle, the ECU will follow various ignition timing
mapping programs. The ECU will maintain timing between 0-29' BTDC for
200 or 250 hp motors and 0-28' BTDC for 225 hp motors.
As long as you are not checking WOT timing, this ignition timing check
can be performed on a flush fitting, as well as with a test tank or on a
launched craft. However, if you wish to check timing from mid-range to WOT,
you'll need to place a load on the propeller (i.e. with a test tank or with a
launched craft) to prevent possible powerhead damage.
BTDC.5ÂATDC and 5'be anywhere between
To check ignition timing:
1. Connect the timing light according to the tool manufacturer's
instructions. It is preferable to use a light that can attach to the primary wiring
for the No. 1 cylinder, but if necessary remove the bolt securing the No. 1
(top cylinder) ignition coil, and pull the coil off the spark plug, then install a
special high tension cord with a plug cap adaptor between the plug and coil
in order to get a timing lightltachometer signal.
 The high tension cord adapter can easily be made from a spare
spark plug wire. Basically it's just a way to remove the direct ignition
coil and place a wire between its spark plug terminal and the actual
spark plug so you can keep the circuit complete and still install an
inductive tachometer pickup.
2. Run the engine at about 1000 rpm in neutral, ignition timing should
Timing marks can be found along with a pointer on the flywheel
cover at the top of the motor.
3. If the motor is mounted on a launched boat or in a test tank you can
also check timing at higher RPM. Timing should vary, from 0-28129' BTDC
depending upon the motor and engine speed.
4 If proper timing is noted during fast idle and/or high rpm operation,
the ECU is controlling engine timing.
ADJUSTMENTS
One of the great benefits of a fuel injected motor is that most of the
functions that are mechanical on a carbureted motor (and therefore subject
to wear and adjustment) are electronically monitored and adjusted to
maximize engine performance. The fuel and ignition systems are all but
completely controlled by the Engine Control Unit (ECU) on these models,
and because of the electronic throttle, even more so than on any other of the
Suzuki outboards. The ECU is a computer control module that accepts input
from various sensors mounted around the engine and makes both ignition
timing and fuel mapping decisions based on those inputs.
ignition timing can be checked using a timing light, but there are no
adjustments. Should it be found out of specification, the electronic engine
control system should be checked for problems. Of course, don't get into the
trap of assuming every problem that arises is electronic. Although the ECU
does an incredible job of regulating engine operation on these motors, it is
subject to the same mechanical limitations of any motor. Mechanical
problems will often manifest themselves in symptoms of the electronic
engine control system and can lead frustration during troubleshooting if you
concentrate only on the electronics.
Similar to ignition timing, the idle speed is also completely electronically
controlled via the electronic throttle system. So like ignition timing no
adjustments are necessary or possible, though also like timing, the idle
speed should be checked annually (or after every 200 hours of operation)
simply to make sure the system is functioning properly.
Checking Idle Speed
Idle speed on 300 hp EFI motors is controlled electronically through the
electronic throttle system. Through management of speed by the ECU
trollinglidle speed in gear should be the same as idle speed in neutral (600-
700 rprn), though a slightly faster speed may be regulated during engine
warm-up to prevent stalling, hesitation or stumble.
B Before checking the idle speed, make sure the throttle control
mechanism and the throttle valve on the throttle body assembly moves
smoothly without binding or resistance.
Suzuki recommends using a battery powered personal computer and the
Suzuki Diagnostic System to check the idle speed, though we are pretty sure
you should be able to use an inductive shop tachometer on the No. 1 spark
plug as long as you install an adaptor (basically a spark plug wire) between
the ignition coil and the plug itself so that you can connect an inductive tach
to the wire.
1. Shift the gearcase into neutral, then start the engine and allow it to
run until it reaches normal operating temperature and idle has fully stabilized.
2. With the engine still funning in neutral, place the throttle control in the
idle position. The engine should idle at a speed of about 600-700 rpm. If the
idle speed is not correct and no mechanical fault can be found the electronic
throttle system may not be functioning correctly.
3. If desired, check the ignition timing at this point.
4. When finished, stop the engine and remove the tachometer.
Checking Ignition Timing
See Figure 196
The ECU controls both the fuel and ignition systems. The ECU adjusts
ignition timing to optimize engine operation based primarily on input from the
Manifold Absolute Pressure (MAP) and Crankshaft Position (CKP) sensors.
However, the ECU also uses input from the Throttle Position Sensor (TPS),
Cylinder Temperature (CT) sensor, Shift Position (SP) sensor and, of course,
the ignition switch itself.
At initial start-up (while cranking), timing is fixed at 5' BTDC for the
starboard bank or 0' BTDC for the port bank. The fixed timing strategy is
used until the engine starts. Once engine speed rises above a
predetermined point, the ECU will begin ignition timing based on
programmed mapping.
During idleltrolling operation the ECU will vary ignition timing to help
stabilize idle speed. The ECU will maintain ignition timing anywhere between
17' ATDC and 7' BTDC with a stable engine speed of about 650 rpm (600-
700 fpm).
For normal operation including acceleration, deceleration and engine
speeds in gear, above idle, the ECU will follow various ignition timing
mapping programs. The ECU will maintain timing between 5ÂATDC and 24
BTDC.
As long as you are not checking WOT timing, this ignition timing check
can be performed on a flush fitting, as well as with a test tank or on a
launched craft. However, if you wish to check timing from mid-range to WOT,
you'll need to place a load on the propeller (i.e. with a test tank or with a
launched craft) to prevent possible powerhead damage.
To check ignition timing:
1. Connect a timing light according to the tool manufacturer's
instructions. It is preferable to use a light that can attach to the primary wiring
for the No. 1 cylinder, but if necessary remove the bolt securing the No. 1
(top cylinder) ignition coil, and pull the coil off the spark plug, then install a
special high tension cord with a plug cap adaptor between the plug and coil
in order to get a timing IighVtachometer signal.
M The high tension cord adapter can easily be made from a spare
spark plug wire. Basically it's just a way to remove the direct ignition
coil and place a wire between its spark plug terminal and the actual
spark plug so you can keep the circuit complete and still install an
inductive timing lightltachometer pickup.
2. Run the engine at about 1000 rpm in neutral, ignition timing should
be anywhere between 0-5Â BTDC.
Timing marks can be found along with a pointer on the flywheel
cover at the top of the motor.
3. If the motor is mounted on a launched boat or in a test tank you can
also check timing at higher RPM. Timing should vary, from 5' ATDC and 24'
BTDC depending upon engine speed.
4. If proper timing is noted during fast idle andlor high rpm operation,
the ECU is controlling engine timing.
See Figures 197 thru 200
Lash is a term which is used to denote the amount of space or freeplay
between two components (or the amount a component can move before that
motion is stopped or affected by another component) so valve lash is the
measured gap that occurs between valve train components when they are
unloaded (when they are not actively holding a valve open).
On these motors valve lash is measured in one of two places, depending
upon the valve train design. All 2.5-30 hp motors, as well as the 60170 hp
motors, are equipped with rocker arm driven valve trains. This means that
the camshaft lobes contact (directly or indirectly) a rocker arm which then
pivots to open a valve (or allow it to close depending on the direction of
travel). On these motors valve lash is the clearance between the rocker arm
and the top of the valve stem.
On all 40150 hp and 90-300 hp motors there are no rocker arms, and
instead the overhead camshafts ride in journals directly above their
respective valves, separated by a shimmed lash adjuster (basically a solid
"lifter" which can hold shims of varying sizes). On these motors the valve
lash is the clearance between the base of the camshaft lobe and the
shimllash adjuster assembly.
In either design, the actual amount of valve lash is critical, as too little
clearance can hold the valve open or keep it from fully contacting the valve
seat, preventing it from cooling by transmitting heat to the cylinder head
through contact. This would lead to a burnt valve, requiring overhaul and
replacement. Also, too much valve clearance might keep the valve from
opening fully, preventing the engine from making maximum horsepower. Of
course poor driveability is arguably better than burning a valve. There's an
older mechanic's saying that applies here, "a tappy valve, is a happy valve."
That's not to say you necessarily WANT your valves a little too loose and
tapping, but whenever you're in doubt, leave a valve a little too loose rather
than a little too tight.
Adjusting valve lash is a part of normal maintenance to keep the valve
clearance within a specified range accounting for the normal wear and tear
of valve train components. Regardless of the differences in the valve trains
covered here, valve clearance is always measured when the rocker or
tappet for the valve being measured is fully released meaning that it is in a
position where it contacts the base of the camshaft and not any part of the
raised camshaft lobe. For this reason it is usually necessary to find when the
piston for the valve being measured is at TDC of the compression stroke.
Remember that TDC of the compression stroke is the point during the 4-
stroke engine cycle when the piston travels upward and both valves close in
order to seal the combustion chamber and compress the airlfuel mixture.
Although timing marks can be used to determine TDC, always double-
check the timing marks by watching the valves for the cylinder on which you
are working as the timing mark on the flywheel or camshaft approaches the
mark on the engine. During a normal cycle, the exhaust valve will close
toward the end of the exhaust stroke (piston traveling up, pushing out gases)
and then the intake valve will open (on the intake stroke, piston traveling
down to draw in airlfuel mixture) and then it will close as the piston begins its
travel upward (on the compression stroke, as it approaches TDC). If instead
the exhaust valve opens, the engine is one full turn of the crankshaft away
from the start of the compression stroke. Both valves must be closed, and
remain closed as the piston comes to the top of the cylinder and the timing
marks align. If so, that piston is on TDC and the valves for that cylinder may
be adjusted.
ADJUSTMENT
DERATE
2.5-6 Hp Motors
@ See Figures 197 and 201
A set of flat feeler gauges is the only tool that is absolutely necessary to
check valve clearance on these motors.
Valve specifications are for an overnight cold engine. It is best to check
andlor adjust the valves with the powerhead at approximately 68'F (2OoC),
1. For safety, and to ease engine compression and make it easy to turn.
remove the spark plug and ground the spark plug lead.
2. Remove the manual starter for access to the flywheel in order to
rotate the crankshaft. Although some people may endeavor to use the
manual starter to accomplish this, it is too easy to turn the flywheel too far
with this method and it can get frustrating if you repeatedly miss TDC. It's a
lot easier to use a breaker bar and a socket on the crankshaft retaining nut.
3. If necessary on 41516 hp motors, remove the motor cover seal.
4. Support the rocker arm cover while removing the four cover bolts
using a simple crossing sequence to prevent cover warpage.
5. Carefully pull the rocker arm cover from the cylinder head. Remove
and discard the old O-ring or gasket, as a new one should be used during
installation to prevent leaks.
6. Rotate the flywheel clockwise to align the timing mark for TDC about
where the timing pointer would normally be (if the manual starter was still
installed). While doing so, make sure the intake and exhaust valves remain
closed as the piston comes up in it's travel. To verify that the piston is indeed
at TDC on the compression stroke, rotate the flywheel about 10-15' beyond
TDC and make sure that neither of the rockers move AT ALL. If they do not
move, you're good to go. If one of the rockers move, then the piston is on
the exhaust stroke and you must rotate the flywheel one more complete turn.
For 41516 hp models, turn the flywheel slowly until the round mark
on the flywheel is facing the round mark on the top centerline of the
powerhead, facing forward toward the carburetorlintake manifold. In
this position, both valves should be closed, confirming that the single
cylinder is at TDC. Both valves can be adjusted in this position.
7. Measure the clearance of the cylinder intake and exhaust valves.
Insert feeler gauges of various sizes between the rocker arm and the valve
Check clearance at each rocker
e stem -2.5-30 hp and 60R0 hp Fig. 199 ...then measure between the shim
and camshaft using a feeler gauge
Fig. 200 Use a micrometer to measure old shims when determining
the proper replacements
stem for both valves being checked at this point. The size gauge that passes
between the arm and stem with a slight drag indicates the valve clearance.
Compare the clearance measured with the specifications of 0.005-0.007 in.
(0.13-0.1 7mm) for 2.5 hp motors or 0.001 -0.003 in. (0.03-0.07mm) for 4/56
hp motors. Since the specifications are the same for both intake and exhaust
valves on these motors it is not critical that you know which-is-which.
However, if you desire, to determine which valve is an intake and which is an
exhaust, observe the position of the valves in relation to the other
components on the powerhead. The intake valves are adjacent to the ports
for the intake manifold attached to the powerhead and the exhaust valves
are adjacent to the exhaust ports.
8. If adjustment is necessary, proceed as follows:
a. Loosen the locknut, then turn the adjusting screw until the clearance
is correct.
b. Hold the screw and tighten the locknut to 60 inch lbs.15 ft. Ibs. (7 Nm)
on 2.5 hp or to 100 inch lbs.18 ft. Ibs. (11 Nm) on 6 hp (128cc) and 8 hp
motors, or to 96 inch lbs.18 ft. Ibs. (11 Nm) on 4/56 hp motors. Double-check
the adjustment to be absolutely certain the adjuster didn't shift while
tightening the locknut,
9. Install a new rocker arm cover gasket (install the gasket dry). On
4/56 hp motors there should be a large tabbed area on the border of the
gasket, when present this should be positioned at the bottom, toward the left
side when facing the gasket and cylinder head.
10. Install and tighten the rocker arm cover bolts using a crossing pattern
to 60 inch lbs.15 ft. Ibs. (7 Nm) on 2.5 hp or to 72 inch lbs.16 ft. Ibs. (8 Nm) on
41516 hp motors.
11. On 41516 hp motors, if removed, install the motor cover seal.
12. Install the manual starter assembly.
13. Install the spark plug and lead.
14. Provide a water source, then start the engine and check for oil leaks
at the rocker arm cover mating surfaces.
15. Install the upper engine cover.
9.9115 Hp Motors
+ See Figures 197 and 202
A set of flat feeler gauges is the only tool that is absolutely necessary to
check valve clearance on these motors, however the process is much easier
when using Suzuki adjustment tool (#09917-14910) or an equivalent tappet
adjustment tool to rotate the valve adjuster, because of the shaft of the
adjusters.
Valve specifications are for an overnight cold engine. It is best to check
andlor adjust the valves with the powerhead at approximately 68° (20%).
1. For safety, disconnect the negative battery cable andlor remove the
spark plugs and ground the spark plug leads. Be sure to tag the spark plug
leads before disconnection. Also, keep in mind that you'll want to remove the
spark plugs to relieve engine compression and make the powerhead easy to
spin anyway.
2. Remove the manual starter or flywheel cover, as applicable, for
access to the flywheel in order to rotate the crankshaft. Although some
people may endeavor to use the manual starter to accomplish this, it is too
Fig. 201 The valve cover must be removed for access for valve
adiustment -41516 ho shown
Cam pulley PUNCH mark
Fig. 202 The punch marks and embossed numbers on the camshaft
pulley will help you find TDC on 9-9/15 hp motors
easy to turn the flywheel too far with this method and it can get frustrating if
you repeatedly miss TDC. It's a lot easier to use a breaker bar andia socket
on the crankshaft retaining nut.
3. For clearance, remove the lower engine covers as described in this
section.
4. On models where the breather hose connects to the cylinder
headlvalve cover, tag and disconnect the hose.
5. Tag and disconnect the fuel inlet and outlet hoses from the fuel pump
(which mounts to the valve cover).
When disconnecting the fuel hoses, use a rag to catch all spilled fuel.
Use extreme care when working around fuel and fumes as both are
highly flammable. Keeping all potential sources of spark or ignition (no
smoking and avoid sparks) out of the work area. Refer to the Fuel
System section for more details.
6. Support the rocker arm cover while removing the six cover bolts
using a crossing or spiraling sequence that starts at the outer bolts and
works inward.
7. Carefully pull the rocker arm cover from the cylinder head. Remove
and discard the old O-ring or gasket, as a new one should be used during
installation to prevent leaks.
8. Rotate the flywheel clockwise in order to align the timing marks for
the valves you are checking. Turn the flywheel slowly until the No. 1 pointer
(small dot next to the embossed 1on the pulley) on the cam pulley aligns
with the protrusion (a small mark at the gasket split line) on the powerhead.
In this position the valves for the No. 1 piston (top) will both be closed,
confirming that the No. 1 piston is a TDC of the compression stroke. To
adjust the valves for the No. 2 piston you will then rotate the flywheel one full
turn so that the camshaft pulley rotates 112 turn so the mark for the No. 2
(bottom) piston will then align with the same protrusion on the powerhead.
9. Measure the clearance of the cylinder intake and exhaust valves.
Insert feeler gauges of various sizes between the rocker arm and the valve
stem for both valves being checked at this point. The size gauge that passes
between the arm and stem with a slight drag indicates the valve clearance.
Compare the clearance measured with the Valve Clearance Specifications
Chart. To determine which valve is an intake and which is an exhaust,
observe the position of the valves in relation to the other components on the
powerhead. The intake valves are adjacent to the ports for the intake
manifold attached to the powerhead and the exhaust valves are adjacent to
the exhaust ports.
M Verify valve positions by watching the pattern of valve opening and
closing while the piston approaches top dead center. You can also
verify by blowing compressed air into a cylinder through the spark plug
opening when only one valve is open and listening for where the air
escapes.
10. If adjustment is necessary, proceed as follows:
a. Loosen the locknut, then turn the adjusting screw until the clearance
is correct.
b. Hold the screw and tighten the locknut to 84 inch lbs.17 ft. Ibs. (10
Nm). Double-check the adjustment to be absolutely certain the adjuster didn't
shift while tightening the locknut.
11. Rotate the flywheel clockwise one full revolution or 360Â in order to
turn the camshaft pulley one half of a revolution or 180¡ The pointer should
now face opposite the timing mark on the starter boss. In this position the
opposite cylinder (No. 2) will be at TDC. Check and adjust the valves for the
other cylinder in the same manner as the first.
12. Install a new rocker arm cover gasket (install the gasket dry). Tighten
the bolts using a spiraling or crossing pattern that starts at the middle and
works outward to 84 inch lbs.17 ft. Ibs. (10 Nm).
13. Reconnect any hoses that were tagged and removed.
14. Install the lower engine covers,
15. Install the manual starter or flywheel cover, as applicable.
16. Install the spark plugs and leads and, if applicable, connect the
negative battery cable.
17. Provide a water source, then start the engine and check for oil leaks
at the rocker arm cover mating surfaces.
10. Install the upper engine cover.
25 Hp V2 Motors
See Figure 197
A set of flat feeler gauges is the only "special" tool that is absolutely
necessary to check valve clearance on these motors (other than the usual
array of hand tools to remove the valve covers).
Valve specifications are for an overnight cold engine. It is best to check
andlor adjust the valves with the powerhead at approximately 68'F (20%).
1. Ifequipped, disconnect the negative battery cable for safety.
2. To relieve engine compression and make it MUCH easier to find
TDC, tag and disconnect the spark plug wires, then remove the spark plugs.
3. For clearance, remove the lower engine covers as described in this
section.
4. Remove the manual starter or flywheel cover, as applicable, for
access to the flywheel in order to rotate the crankshaft. Although some
people may endeavor to use the manual starter to accomplish this, it is too
easy to turn the flywheel too far with this method and it can get frustrating if
you repeatedly miss TDC. It's a lot easier to use a breaker bar and a socket
on the crankshaft retaining nut.
5. Support each rocker arm cover while removing the four cover bolts
using a simple crossing pattern to help protect the covers). Carefully pull the
rocker arm cover from the cylinder head, then remove and discard the old
rocker cover gaskets.
6. Rotate the flywheel clockwise in order to align the timing marks, then
start by checking both the intake and exhaust valves for the No. 1 (starboard
side) cylinder. Remember though that for every two times the flywheel timing
marks align the piston is only a TDC of the compression stroke one time.
The absolute BEST way to determine if the No. 1 cylinder is on the
compression stroke (as opposed to the exhaust stroke) is to watch the
valves. If the intake valve just closed before the piston started traveling
upward then you're on the compression stroke. If however the exhaust valve
OPENED, well, then you know you're a full turn of the flywheel away from
TDC compression.
7. Once you're certain the cylinder you are checking is on TDC of the
compression stroke and that both valves a fully closed (not being held open
by the camshaftslrockers), measure the clearance of the cylinder intake and
exhaust valves. Insert feeler gauges of various sizes between the rocker arm
and the valve stem for both valves being checked at this point. The size
gauge that passes between the arm and stem with a slight drag indicates the
valve clearance. Compare the clearance measured with the Valve Clearance
Specifications Chart (should be 0.001-0.003 in10.03-0.07mm for both the
intake and exhaust valves on these models). To determine which valve is an
intake and which is an exhaust (not that it is that important since the specs
are the same, but for posterities sake), observe the position of the valves in
relation to the other components on the powerhead. The intake valves are
adjacent to the ports for the intake manifold attached to the powerhead and
the exhaust valves are adjacent to the exhaust ports. On these motors, that
should meant the intake valve is on top and the exhaust valve is on the
bottom.
@ Verify these valve positions by watching the pattern of valve
opening and closing while the piston approaches top dead center. You
can also verify by blowing compressed air into a cylinder through the
spark plug opening when only one valve is open and listening for
where the air escapes.
8. If adjustment is necessary, proceed as follows:
a. Loosen the locknut, while holding the pivot (adjusting) nut, then turn
the adjusting nut until the clearance is correct.
b. Hold the pivot (adjusting) nut and tighten the locknut to 95 inch lbs.18
ft. Ibs. (11 Nm). Double-check the adjustment to be absolutely certain the
adjuster didn't shift while tightening the locknut.
9. Rotate the flywheel clockwise until the intake valve closes fully and
the piston comes to the top of travel for the No. 2 (Port) side cylinder. Now
with the No. 2 cylinder a TDC of the compression stroke, check and adjust
its valves.
10. Once you are finished install the rocker covers using the retaining
bolts and NEW gaskets (no sealant). Tighten the bolts gradually for each
rocker cover using a crossing pattern to 88 inch lbs.17.2 ft. Ibs. (10 Nm).
11. Install the lower engine covers.
12. Install the manual starter or flywheel cover, as applicable.
13. Install the spark plugs and leads and, if applicable, connect the
negative battery cable.
14. Provide a water source, then start the engine and check for oil leaks
at the rocker arm cover mating surfaces.
15. Installthe upper engine covet.
25/30 Hp (3-Cyl) Motors
See Figures 197 and 203
A set of flat feeler gauges is the only thing close to a "special" tool
necessary to check valve clearance on these motors.
Valve specifications are for an overnight cold engine. It is best to check
and/or adjust the valves with the powerhead at approximately 20% (68'F).
1. For safety, disconnect the negative battery cable and/or remove the
spark plugs and ground the spark plug leads. Be sure to tag the spark plug
leads before disconnection. Also, keep in mind that you'll want to remove the
spark plugs to relieve engine compression and make the powerhead easy to
spin anyway.
2. Remove the manual starter or flywheel cover, as applicable, for
access to the flywheel in order to rotate the crankshaft. Although some
people may endeavor to use the manual starter to accomplish this, it is too
easy to turn the flywheel too far with this method and it can get frustrating if
you repeatedly miss TDC. It's a lot easier to use a breaker bar and a socket
on the flywheel retaining bolt.
3. For clearance, remove the lower engine covers as described in this
section.
4 Tag and disconnect the breather hose from the top corner of the
cylinder head cover.
5. Using a crossing pattern, slowly and evenly loosen, then remove the
8 cylinder head cover retaining bolts. Pull the cover away from the cylinder
head carefully breaking the gasket seal (but taking care as the gasket, if
undamaged, is reusable on these models).
H Inspect the gasket for damage. If the gasket is in good shape it is
reusable on most models, but consider how easy it was to get to and
whether or not you'd want to bother redoing that work to replace it,
should it leak after testing.
6. Rotate the flywheel clockwise while watching the operation of the
valves to determine when each cylinder is on TDC. Unfortunately the timing
chain on this motor is mounted UNDER the powerhead, so there is no visible
camshaft pulley with marks to use as a guide. Also, the timing pointer was
removed with the manual starter or flywheel cover, though you can position it
over top the flywheel for a second in order to get a general idea where the
pointer would be (which is fine, because you don't have to be SPOT on TDC
to adjust the valves, you just need to be close enough that you're certain the
rockers are on the base lobes of the camshaft). Now you may be able to see
enough of the camshaft to determine directly when a given valve is on the
base of the lobe, and in that case, you can do each of the valves individually,
regardless of searching for TDC. Otherwise, watch the movement of the
valves in relation to the movement of the piston. When the exhaust valve is
already closed and the intake valve CLOSES as the piston approaches the
top of travel, then you are on the compression stroke for that cylinder. Adjust
the valves with the piston as high as possible in the cylinder and BOTH
valves closed.
7. Measure the clearance of the cylinder intake and exhaust valves.
Insert feeler gauges of various sizes between the rocker arm and the valve
stem for both valves being checked at this point. The size gauge that passes
between the arm and stem with a slight drag indicates the valve clearance.
Compare the clearance measured with the Valve Clearance Specifications
Chart. Since the valve clearance specification is the same for both valve it
isn't critical to determine which is the intake and which is the exhaust valve,
unless of course you're still trying to determine where TDC is for that piston.
Two hints in determining which valve is which. First, observe the position of
the valves in relation to the other components on the powerhead. The intake
valves are adjacent to the ports for the intake manifold attached to the
powerhead and the exhaust valves are adjacent to the exhaust ports.
Second, remember that during crankshaft rotation the exhaust valve and
intake valve TEND to have a small amount of overlap (the exhaust valve is in
the process of closing when the intake valve opens), but the opposite is not
true (the intake valve should never be still opened when the exhaust valve
starts to open).
8. If adjustment is necessary, loosen the locknut, then use a driver to
slowly and gently turn the adjusting screw until the clearance is correct. Hold
the adjusting screw firmly and tighten the locknut to 97 inch lbs.18 ft. Ibs. (11
Nm), then double-check the adjustment to be absolutely certain the adjuster
didn't shift while tightening the locknut.
9. Now, rotate the flywheel again clockwise while watching the next
cylinder's set of valves and repeat the check/adjustment for the next cylinder.
Continue until the valves for all 3 cylinders have been checked and adjusted.
10. Apply a [email protected] of Suzuki Bond No. 1207B or equivalent to the
Fig. 203 Disconnect the breather hose from the upper corner of the
valve cover before removal -25/30 hp (3-cyl motors)
two small joint lines (one on each side, toward the very bottom) of the
cylinder head-to-cover gasket mating surface.
11. Make sure the cylinder head cover gasket is in good condition. Install
the cover and loosely run the 8 retaining bolts down by hand, then tighten
them using a crossing pattern to 97 inch lbs.18 ft. Ibs. (11 Nm).
12. Install the lower engine covers.
13. Install the manual starter or flywheel cover, as applicable.
14. Install the soark oluas and leads and. if annlicable. connect the
> -8,
.
negative battery cable.
15. Provide a water source, then start the engine and check for oil leaks
at the rocker arm cover mating surfaces.
16. Install the upper engine cover.
40150 Hp Motors
@ See Figures 198,199,200 and 204 thru 210
The 40150 hp motors utilize replaceable shims to adjust valve clearance.
A set of flat feeler gauges is all that is required to check valve clearance.
But, if adjustments are necessary, you will need a micrometer for shim
measurement, an assortment of shims (or a trip during the procedure to
purchase the proper size shims) and Suzuki #09916-67010 or an equivalent
tappet holder tool.
H These motors utilize a dual overhead camshaft arrangement driven
by a timing chain and sprockets which are mounted at the BOTTOM of
the cylinder. As such, unless the powerhead has been removed for
repair, the timing marks on those sprockets are rather useless when it
comes to finding TDC and checking valve clearance. Instead, since the
camshafts are in plain site (once the cylinder head cover is removed)
use them to determine if a given cylinder is on TDC. Remember, the
intake valve will be the last to close, right about the time the piston
begins to travel back upwards. When the piston on any given cylinder
reaches the top of travel and BOTH the intake and exhaust valves for
that cylinder are closed, then the cylinder is at TDC.
Valve specifications are for an overnight cold engine. It is best to check
and/or adjust the valves with the powerhead at approximately 20¡ (6VF).
1. For safety, disconnect the negative battery cable.
2. Remove the ignition coils and spark plugs as described in this
section.
3. Remove the lower engine covers as described in this section.
4. Remove the flywheel cover as described under Powerhead.
5. Rotate the enaine clockwise to brina the No. 1 cvlinder to TDC of the
compression stroke and thereby relieving mechanical pressure from the fuel
numo arm. Remove the low oressure fuel numo from the cvlinder head cover
, ,
as described in the Fuel system section.
M Suzuki actually just tells techs to disconnect the hoses and leave
the fuel pump attached to the valve cover. We've found that it can be a
pain during installation and it is usually just easier to remove it. But do
as you prefer.
Valve Cover
Tightening
Sequence
Valve Cover
Loosening
Sequence
Fig. 204 On these motors you have to disconnect or remove a Fig. 205 Valve cover loosening and tightening sequences -40150 hp
number of components before unbolting the valve cover motors
of tappet
Special tool
sing bolt
3-Camshaft
b
2-TWet
Fig. 208 Before removing the tappet holder,
Fig. 206 Positioning the valve shim for use the camshaft lobe to press the valve,
removal Fig. 207 Installing the tappet holder tool unloading the tool
6. Disconnect the harness from the camshaft position sensor. For
details, please refer to Electronic Engine Controls.
7. Tag and disconnect the breather hose from the top of the cylinder
head cover.
8. Loosen and remove the 12 cylinder head cover bolts in the opposite
of the tightening sequence (basically by using a crossing pattern that starts
at the upper and lower ends of the valve cover and works inward).
9. Remove the cover along with the gasket and O-rings from the
powerhead. Be careful not to damage the cover gasket or any O-rings if you
have any intention of trying to reuse them. Inspect the gasket for damaged
surfaces and reolace. if necessarv.
E Suzuki recommends replacing the valve cover gasket and spark
plug bore O-rings anytime the cover is removed.
10. Check that the flywheel is still in the No. 1 TDC position by making
sure the camshaft lobes face out and directly away from (meaning facing
away from or not pushing on) the valve tappets for that cylinder. Insert feeler
gauges of various sizes between the tappet shim and the camshaft lobe. The
size gauge that passes between the shim and lobe with a slight drag
indicates the valve clearance. Record the clearance for each valve.
11. The firing order on this motor is 1-3-2, so the No. 3 cylinder should
come up to TDC next and the No. 2 cylinder last, then the cycle will return
back to the beginning of the firing order. Rotate the flywheel clockwise until
the No. 3 camshaft lobe tips are facing out and directly opposite the valve
tappets. Insert feeler gauges of various sizes between the tappet shim and
the camshaft lobe. The size gauge that passes between the shim and lobe
with a slight drag indicates the valve clearance. Record the valve clearance
^Or each -
12. Rotate the flywheel clockwise until the No. 2 camshaft lobe tips are
facing out and directly opposite the valve tappets. Insert feeler gauges of
various sizes between the tappet shim and the camshaft lobe. The size that
Passes between the shim and lobe with a slight drag indicates the valve
clearance. Record the valve clearance for each valve.
13. Comoare the clearances with the Valve Clearance Soecifications
chart in this section (it should be 0.007-0.009 in.10.18-0.24mm for both intake
and exhaust valves).
14. If incorrect valve clearance is noted, substitute the proper sized shim,
determined as follows:
a. If valve clearance is greater than spec, subtract the valve clearance
specification (using the dead middle of the range) listed in the specification
chart from the measured clearance. Obtain a replacement shim, that much
thicker than the current shim.
b. If valve clearance is less than specification, subtract the measured
clearance from the valve clearance specification (again, using the dead
middle of the range) listed in the chart. Obtain a replacement shim that much
smaller than the original.
218 220 222 224 226 226 230 232 234 238 238 240 242 244 246 246 250 252 254 256 2% 260 262 264 266 268 270 272 274 276 276 280 282 284 286 288 290 292 294 296 298 300
2. 22 222 2.24 2.28 2.28 2.30 2.32 2.34 2.36 2.38 2.40 2.42 2.46 2.46 2.48 2.50 2.52 2.54 2.56 2.58 2.60 2.62 2.64 2.06 2.68 2.70 2.72 2.74 2.76 2.78 2.80 2.82 2.84 2.88 2.88 2.90 2.92 2.94 2,546 2.98 3.00
clearance
{mm)
0.00 -0.04
218 220 222 224 226 226 230 232 234 236 238 240 242 244 246 246 250 252 254 256 256 260 262 264 266 268 270 272 274 276 278 280 282
I
0.05 -0.09 218 220 222 224 226 228 230 232 234 236 238 240 242 244 248 248 250 252 254 256 258 260 262 284 266 268 270 272 274 276 278 280 282 284 286
0.10-0.14 218 220 222 224 226 228 230 232 234 236 238 240 242 244 248 248 250 252 254 256 258 260 262 264266 268 270 272 274 276 278 280 282 264 266 288 290 292
0.15-0.17 216 220 222 224 226 228 230 232 234 236 230 240 242 244 246 248 250 252 254 253 258 260 262 264 266 268 270 272 274 276 278 280 282 284 286 268 290 292 294 296
0.18 -0.24
SPECIFIEDCLEARANCE 1 NO ADJUSTMENT REQUIRED
0.25 -0.29 224226226230232234236238240242244246'248'250~ 252254'25~258'26026226-1266268 270272'274276278280282284286288290292294296298~300
0.30-0.34 230 232 234 236 238 240 242 244 246 248 250 252 254 256 258 260 262 264 266 266 270 272 274 276 278 280 282 284 286 288 290 292 294 296 290 300
0.35 -0.39 234 236 238 240 242 244 246 248 250 252 254 256 258 260 262 264 266 268 270 272 274 276 276 280 282 284 286 288 280 292 294 296 298 300
1. Measure tappet clearance "Engine cold".
2.
Measure present shim size.
3.
Match clearance in vertical column with
present shim size in horizontal column.
[EXAMPLE]
Tappet clearance is -0.35 mm
Present shim size -2.40 mm
Shim size to be used -2.56 rnm
Fig. 209 Valve tappet shim selection chart -40150 hp motors
Alternately you can use the accompanying shim selection chart in
order to choose the appropriate replacement shim. For example, say
you measured a clearance of 0.46mm, and the current shim is a
2.34mm (marked 234). First look down the left outer column to locate
the row for 0.46mm (it is the 10th row down, marked 0.45-0.49mm). Next Apply sealant to
look across the top for the 234 shim (2.34mm), it is the 9th column over dark shaded
from the left. Follow the column down to the point where it intersects mating surfaces
with the 0.45-0.49mm row and you'll find that the proper new shim
would be marked 260 for 2.6mm. You can also tell from the chart that
replacement shims are available from 218 (2.18mm) to 300 (3.0mm) in
0.02mm increments.
VALVE
COVER
15. If shim replacement is necessary to obtain the proper valve lash:
a. Rotate the flywheel clockwise until the camshaft lobe tip for the
selected vaive is opposite the tappet (facing out, 180' away from the tappet).
b. Carefully rotate the tappet within its bore until the notch is facing
toward the opposite camshaft. The notch must be accessible for tappet shim
removal.
c. Rotate the flywheel clockwise until the camshaft lobe tip contacts the
tappet shim (opening the vaive and creating room for the tool). Remove the
bolts from the camshaft cap next to the selected vaive. CYLINDER
HEAD
d. Place Suzuki #09916-67010 or an equivalent tappet retainer over the
camshaft cap. Each end of the retainer is marked either IN (for intake) or EX
(for exhaust) and the appropriate end must face inward toward the center of
the cylinder head (toward the notch on the tappet from which the shim will be
removed). Thread the camshaft cap bolts through the retainer and the
camshaft cap. Tighten the bolts securely, ensuring the fingers of the tool
contact the barrel portion of the tappet and not the shim itself.
e. Rotate the flywheel clockwise one half revolution or until the
camshaft lobe tip rotates 90' away from the tappet. Use a small magnet to
Fig. 210 Apply a light coating of Suzuki Bond No. 1207B to the grab and remove the shim. If absolutely necessary, insert a screwdriver (with
cylinder head gasket mating surface and the valve cover (with tape covering the blade to prevent scoring or damage) into the tappet notch
gasket installed) at the darkshaded areas at the top of the cylinder and carefully pry the shim from the tappet, then use the magnet to pull the
head and bottom side of the valve cover shim from the tappet. DO NOT use your fingers.
DO NOT let your fingers get between the camshaft and tappet at any
time, as they could be crushed if the tool or camshaft suddenly shifted.
f. Measure the shim thickness using a micrometer. Shims are available
in sizes from 0.086-0.118 in. (2.18-3.0mm) in 0.001 in. (0.02mm) increments.
Select the correct shim thickness as described earlier. '
H On new shims, the thickness can be identified by the number
present on the shim's face, divided by 100. Move the decimal point 2
places to the left and you've got your size. For example a new shim
labeled 258 on the face is 2.58mm thick. The label can only be trusted
on new shims, which have not been in service, as normal wear during
service might change shim thickness overtime.
g. Place the selected shim into the tappet with the numbered side
facing down TOWARD the tappet.
h. Make sure the shim seats fully against the step within the tappet,
then rotate the flywheel counterclockwise one half revolution or until the
camshaft lobe tip contacts the shim (pushing the tappet downward and
taking the load off the tappet holder tool so it can be safely removed. Loosen
and remove the bolts from the camshaft cap and tappet retainer.
i Carefully pull the retainer from the cap, then install camshaft cap bolts
and tighten evenly to 89 inch lbs.17 ft. Ibs. (10 Nm).
16. Repeat for each of the valves whose lash was noted out of
specification. Once you are finished with any shim changes, recheck the
clearance for that valve. And once you are finished with all valve clearance
checks, reset the powerhead to No. 1 TDC to ease fuel pump and/or valve
cover installation, as applicable
17. Install a new valve cover gasket and set of spark plug bore O-rings
on the underside mating surface of the valve cover.
Fig. 212 The camshaft sprocket has
Fig. 211 Remove the spark plugs and the individual marks to align each cylinder at
ignition coils. . .
18. Apply a light coating of Suzuki Bond No. 1207B, or equivalent, to the
proper portions of the cylinder head cover mating surfaces. At the top of the
cylinder head, along the mating surface for the valve cover, apply sealant to
the rounded pockets just above the camshafts. Make sure the sealant comes
all the way to the flat surfaces on either side of the rounded pockets, and to
the rest of the horizontal gasket surface to the LEFT of the cam on the left
side (when looking at the head), but DO NOT coat the entire horizontal
surface between the two rounded pockets. Also, on tne cylinder head
COVERIGasket itself, apply sealant to the two slightly-rounded, vertical
surfaces at the widest part (bottom ears) of the cover.
19. Install the cover to the cylinder head making sure the spark plug port
O-rings are not dislodged when you are seating it, then install and tighten the
cover bolts using the torque sequence (which is essentially a crossing
pattern that starts at the center and works outward) to 89 inch lbs.17 ft. Ibs.
(10 Nm).
20. Reconnect the harness to the camshaft position sensor.
21. Reconnect the breather hose.
22. Install the spark plugs and the ignition coils.
23. Install the fuel pump, flywheel cover and lower engine covers as
detailed in the appropriate procedures.
24. Connect the negative battery cable, then connect a flushing device
and start the engine to check for oil leaks at the rocker arm cover mating
surfaces.
25. Install the engine top cover.
60170 Hp Motors
See Figures 197 and 211 thru 216
A set of flat feeler gauges is necessary to check valve clearance on these
motors.
Valve specifications are for an overnight cold engine. It is best to check
and/or adjust the valves with the powerhead at approximately 20% (68'F).
INDEX mark PUNCH mark
PUNCH mark
Fig. 213 Rotate the flywheel until the
camshaft sprocket is aligned at No. 1TDC...
Fig. 214 ...then remove the fuel pump (or 15 Tag and disconnect the breather Fig. 216 ...then loosen the bolts and
at least tag & disconnect the hoses) remove the valve cover
The No. 1cylinder is at TDC of the compression stroke on the 60/70
hp motor, when the punch mark on the crankshaft timing pulley aligns
with the protrusion on the cylinder block and the No. 1mark on the
camshaft pulley aligns with the raised boss on the cylinder head. Now,
with the flywheel installed you can't see the crankshaft timing pulley,
but you may also use the flywheel timing marks and the timing pointer
as a reference. Of course, since the valve cover will be removed at
some point during the procedure the BEST method is to keep an eye
on the camshaft lobes as the camshaft timing marks come up to
alignment. At TDC of a compression stroke, the base of the camshaft
lobe will be touching the rocker arm (the raised portion of the lobe will
face away from the rocker). There are 4 numbered punch marks on the
camshaft pulley, each functions as the TDC alignment mark for that
numbered cylinder.
1. Disconnect the negative battery cable for safety.
2. For access, remove the lower engine covers as described in this
section.
3. Tag and disconnect the spark plug wires, then remove the spark
plugs to relieve engine compression. For details, please refer to the Spark
Plug procedure in this section.
Ground the spark plug leads to prevent damage if the engine is
cranked while they are disconnected.
4. Remove the ignition coils from the cylinder head. For details, refer to
the Ignition System section.
5. Remove the flywheel cover as described under Powerhead. Before
removing the cover, take note of the approximate position of the timing
pointer to help determine TDC in the next step.
6. Rotate the engine clockwise to bring the No. 1 cylinder to TDC of the
compression stroke and thereby relieving mechanical pressure from the fuel
pump arm. Remove the low pressure fuel pump from the cylinder head cover
as described in the Fuel System section.
M Suzuki actually just tells techs to disconnect the hoses and leave
the fuel pump attached to the valve cover. We've found that it can be a
pain during installation and it is usually just easier to remove it.
as you prefer.
7. Tag and disconnect the breather hose from the cylinder head cover.
8. Support the rocker arm cover and remove the six cover bolts using a
crossing pattern.
9. Pull the rocker arm cover from the cylinder head, then carefully
remove the cover gasket.
10. Make sure the flywheel is still in the No. 1 TDC position. The raised
portion of the camshaft lobes should face away from and not be in contact
with the rockers. If the position is correct, both the valves for the No. 1
cylinder will be closed.
11. Measure the clearance intake and exhaust valves for the No. 1
cylinder (in the past the Suzuki also used to recommend measuring the No.
2 cylinder intake valve and the No. 3 cylinder exhaust valve at this point, and
you can if for some reason your camshaft pulley doesn't have all the marks,
or you can use the additional timing marks provided on the cam pulley to
check each cylinder in succession). Insert feeler gauges of various sizes
between the rocker arm and the valve stem for each valve. The size that
passes between the arm and stem with a slight drag indicates the valve
clearance. Comoare the clearance measured with the Valve Clearance
Specification chart in this section.
12. If lash is out of specification on one or more valve, adjust it as
follows:
a. Loosen the locknut, then turn the adjusting screw until the clearance
is correct.
b. Hold the screw while tightening the locknut to 150 inch lbs.il2.5 ft.
Ibs. (17 Nm).
c. Recheck the valve clearance to make sure the adjuster wasn't turned
while tightening the locknut.
13. If checking each cylinder's valves individually when only that cylinder
is at TDC, then rotate the flywheel clockwise 112 turn, so the camshaft
sprocket rotates 114 turn, bringing the next cylinder punch mark up into
alignment (since the firing order is 1-3-4-2, that means the No. 3 cyl punch
mark should be next). Check and/or adjust the valve clearance on the No. 3
cylinder then repeat this step for the No. 4 and No. 2 cylinders, in
succession.
efore Suzuki labeled each of the 4 TDC marks on the camshaft
they used to suggest checking all valves with either the No. 1or the
No. 4 cylinder at TDC. The valves that would be checked with the No. 1
at TDC were noted earlier, the rest, would be checked with No. 4. This
method is fine, as long as all valves in question are checked while the
tappets are only facing the base (non-raised) portions of the camshaft
lobes. If using this method, after the No. 1TDC position rotate the
crankshaft one full revolution (360') so the No. 4 TDC mark aligns with
the raised boss on the cylinder head (and the No. 1cylinder is now on
its exhaust stroke). The camshaft rotates at 112 the rate of the
crankshaftlflywheel, so rotating the flywheel as directed will turn the
camshaft sprocket only 180". This places the No. 1TDC mark exactly
112 a turn away from the previous location. At this point, both of the
valves for the No. 4 cylinder should be closed. Then measure the
clearance of the No. 4 cylinder intake and exhaust valves, the No 2
exhaust valve and the No. 3 intake valve.
14. Once you are finished checked andlor adjusting the valves, rotate the
flywheel clockwise again until the No. 1 TDC mark again aligns with the
raised boss on the cylinder head. This is done to ease installation of the fuel
pump (or the rocker cover if the fuel pump is still installed).
15. Install the rocker arm cover using a new gasket, then tighten the
bolts using a crisscross pattern to 89 inch lbs.17 ft. Ibs. (10 Nm).
16. Reconnect the breather hose to the rocker cover.
17. Install the fuel pump, ignition coils, spark plugs, flywheel cover and
lower engine covers as described in the appropriate procedures.
18. connect the negative battery cable,' then connect a flushing device
and start the engine to check for oil leaks at the rocker arm cover mating
surfaces.
19. Install the engine top case.
ee Figures 198 thru 200,206 thru 208, and 217 thru 219
The 90i1151140 hp motors utilize replaceable shims to adjust valve
clearance.A set of flat feeler gauges is all that is required to check valve
clearance. But. if adjustments are necessary, you will need a micrometer for
shim measurement, an assortment of shims (or a trip during the procedure to
purchase the proper size shims) and Suzuki #09916-49040 or an equivalent
tappet holder tool.
There is some question as to the style of tool which is sold for this motor.
Some factory sources show #09916-49040 as a bridge-type tool that is
bolted in place over the camshaft bearing cap to depress and hold the valve
tappet. This is the type we have illustrated. Other sources suggest that it is
NOT a bolt-on bridge-type tool, but instead a pair of specialized pliers and
lever that is instead used to manually depress the tappet. We've included
instructions here for use of the bridge-type tool, because that's how Suzuki
technical literature describes it. However, if using a pliersllever type tool set,
use the instructions included with the tool set instead.
These motors are LH rotating. That is, they rotate
COUNTERCLOCKWISE when looking downward at the flywheel. DO
NOT turn them in the wrong direction, or you risk damaging the water
pump impeller vanes.
These motors utilize a dual overhead camshaft arrangement driven
by a timing chain and sprockets which are mounted at the BOTTOM of
the cylinder. As such, unless the powerhead has been removed for
repair, the timing marks on those sprockets are rather useless when it
comes to finding TDC and checking valve clearance. Instead, since the
camshafts are in plain site (once the cylinder head cover is removed)
use them to determine if a given cylinder is on TDC. Remember, the
intake valve will be the last to close, right about the time the piston
begins to travel back upwards. When the piston on any given cylinder
reaches the top of travel and BOTH the intake and exhaust valves for
that cylinder are closed, then the cylinder is at TDC.
Valve specifications are for an overnight cold engine. It is best to check
andlor adjust the valves with the powerhead at approximately 20° (68'F).
1. For safety, disconnect the negative battery cable.
2. Remove the lower engine covers as described in this section.
3. Remove the spark plugs as described in this section.
4. Remove the flywheel cover as described under Powerhead.
5. Tag and disconnect both the breather hose and the evaporation hose
from the upper corner of the cylinder head cover.
6. Rotate the engine COUNTERCLOCKWISE to bring the No. 1
cylinder to TDC of the compression stroke and thereby relieving mechanical
pressure from the fuel pump arm. Remove the low pressure fuel pump from
the cylinder head cover as described in the Fuel System section.
B Suzuki actually just tells techs to disconnect the hoses and leave
the fuel pump attached to the valve cover. We've found that can be bit
of a pain during installation and it is usually just easier to remove it.
ut do as you prefer.
VALVE COVER
TIGHTENING
SEQUENCE
VALVE COVER
LOOSENING
SEQUENCE
Fig. 217 Valve cover loosening and tightening sequences -
90/115/140 hp motors
7. Loosen and remove the 15 cylinder head cover bolts in the opposite
of the tightening sequence (basically by using a crossing pattern that starts
at the lower and upper ends of the valve cover and works inward).
8. Remove the cover along with the gasket and O-rings from the
powerhead. Be careful not to damage the cover gasket or any O-rings if you
have any intention of trying to reuse them. Inspect the gasket for damaged
surfaces and replace, if necessary.
Suzuki recommends replacing the valve cover gasket and spark
plug bore O-rings anytime the cover is removed.
9. Check that the flywheel is still in the No. 1 TDC position by making
sure the camshaft lobes face out and directly away from (meaning not
pushing on) the valve tappets for that cylinder. Insert feeler gauges of
various sizes between the tappet shim and the camshaft lobe. The size
gauge that passes between the shim and lobe with a slight drag indicates
the valve clearance. Record the clearance for each valve.
10. The firing order on this motor is 1-3-4-2, so the No. 3 cylinder should
come up to TDC next, followed by the No. 4 cylinder and the No. 2 cylinder
last, then the cycle will return back to the beginning of the firing order. Rotate
the flywheel counterclockwise until the No. 3 camshaft lobe tips are facing
out and directly opposite the valve tappets. Insert feeler gauges of various
sizes between the tappet shim and the camshaft lobe. The size gauge that
passes between the shim and lobe with a slight drag indicates the valve
clearance. Record the valve clearance for each valve.
11. Rotate the flywheel counterclockwise until the No. 4 camshaft lobe
tips are facing out and directly opposite the valve tappets. Insert feeler
gauges of various sizes between the tappet shim and the camshaft lobe. The
size that passes between the shim and lobe with a slight drag indicates the
valve clearance. Record the valve clearance for each valve.
12. Rotate the flywheel counterclockwise until the No. 2 camshaft lobe
tips are facing out and directly opposite the valve tappets. Insert feeler
gauges of various sizes between the tappet shim and the camshaft lobe. The
size that passes between the shim and lobe with a slight drag indicates the
valve clearance. Record the valve clearance for each valve.
13. Compare the clearances with the Valve Clearance Specifications
chart in this section.
14. If incorrect valve clearance is noted, substitute the proper sized shim,
determined as follows:
a. If valve clearance is greater than spec, subtract the valve clearance
specification (using the dead middle of the range) listed in the specification
1.
Measure tappet clearance "Engine cold".
2.
Measure present shim size.
3.
Match clearance in vertical column with present
shim size in horizontal column.
[EXAMPLE]
Tappet clearance is -0.35 rnrn
Present shim size -2.40 rnrn
Shim size to be used -2.50 rnrn
Fig, 218 Valve tappet shim selection chart -90/115/140 hp motors
chart from the measured clearance. Obtain a replacement shim, that much
thicker than the current shim.
b. If valve clearance is less than specification, subtract the measured
clearance from the valve clearance specification (again, using the dead
middle of the range) listed in the chart. Obtain a replacement shim that much
smaller than the original.
Alternately you can use the accompanying shim selection chart in
order to choose the appropriate replacement shim. For example, say
you measured a clearance of 0.46mm, and the current shim is a
2.40mm (marked 240). First look down the left outer column to locate
the row for 0.46mm (it is the 10th row down, marked 0.43-0.47mm). Next
look across the top for the 240 shim (2.40mm), it is the 10th column
over from the left. Follow the column down to the point where it
intersects with the 0.43-0.47mm row and you'll find that the proper new
shim would be marked 260 for 2.6mm. You can also tell from the chart
that replacement shims are available from 218 (2.18mm) to 300 (3.0mm)
in varying increments of either 0.02mm or 0.03mm.
15. If shim replacement is necessary to obtain the proper valve lash use
a bridge-type tappet holder tool as follows:
a. Rotate the flywheel counterclockwise until the camshaft lobe tip for
the selected valve is opposite the tappet (facing out, 180' away from the
tappet).
b. Carefully rotate the tappet within its bore until the notch is facing
toward the opposite camshaft. The notch must be accessible for tappet shim
removal.
c. Rotate the flywheel counterclockwise until the camshaft lobe tip
contacts the tappet shim (opening the valve and creating room for the tool).
Remove the bolts from the camshaft cap next to the selected valve.
d. Place the tappet retainer over the camshaft cap. Each end of the
retainer is marked either IN (for intake) or EX (for exhaust) and the
appropriate end must face inward toward the center of the cylinder head
(toward the notch on the tappet from which the shim will be removed).
Thread the camshaft cap bolts through the retainer and the camshaft cap.
Tighten the bolts securely, ensuring the fingers of the tool contact the barrel
portion of the tappet and not the shim itself.
e. Rotate the flywheel counterclockwise one half revolution or until the
camshaft lobe tip rotates 90Â away from the tappet. Use a small magnet to
drab and remove the shim. If absolutely necessarv, insert a screwdriver (with
tape covering the blade to prevent scoring or damage) into the tappet notch
and carefully pry the shim from the tappet, then use the magnet to pull the
shim from the tappet. DO NOT use your fingers.
Apply sealant to
dark shaded
mating surfaces
VALVE
COVER
CYLINDER
HEAD
Fig. 219 Apply a light coating of Suzuki Bond No. 1207B to the
cylinder head gasket mating surface and the valve cover (with
gasket installed) at the dark shaded areas at the top of the cylinder
head and bottom side of the valve cover
DO NOT let your fingers get between the camshaft and tappet at any
time, as they could be crushed if the tool or camshaft suddenly shifted.
f. Measure the shim thickness using a micrometer. Shims are available
in sizes from 0.086-0.118 in. (2.18-3.0mm) in varying increments of either
0.00078 in. (0.02mm) or 0.00118 in (0.03mm). Select the correct shim
thickness as described earlier.
On new shims, the thickness can be identified by the number
present on the shim's face, divided by 100. Move the decimal point 2
places to the left and you've got your size. For example a new shim
labeled 258 on the face is 2.58mm thick. The labe! can only be trusted
on new shims, which have not been in service, as normal wear during
service might change shim thickness overtime.
g. Place the selected shim into the tappet with the numbered side
facing down TOWARD the tappet.
h. Make sure the shim seats fully against the step within the tappet,
then rotate the flywheel counterclockwise one half revolution or until the
camshaft lobe tip contacts the shim (pushing the tappet downward and
taking the load off the tappet holder tool so it can be safely removed. Loosen
and remove the bolts from the camshaft cap and tappet retainer.
i Carefully pull the retainer from the cap, then install camshaft cap bolts
and tighten evenly to 96 inch lbs.18 ft. Ibs. (11 Nm).
16. Repeat for each of the valves whose lash was noted out of
specification. Once you are finished with any shim changes, recheck the
clearance for that valve. And once you are finished with all valve clearance
checks, reset the powerhead to No. 1 TDC to ease fuel pump installation.
17. Install a new valve cover gasket and set of spark plug bore O-rings
on the underside mating surface of the valve cover.
18. Apply a light coating of Suzuki Bond No. 12076 or equivalent to the
appropriate portions of the cylinder head cover mating surfaces. At the top of
the cylinder head, along the mating surface for the valve cover, apply sealant
to the rounded pockets just above the camshafts. Also, on the cylinder head
COVERIGasket itself, apply sealant to the two slightly-rounded, vertical
surfaces at the widest part (bottom ears) of the cover.
19. Install the cover to the cylinder head making sure the spark plug port
O-rings are not dislodged when you are seating it, then install and tighten the
cover bolts using the torque sequence (which is essentially a crossing
pattern that starts at the center and works outward) to 96 inch lbs.18 ft. Ibs,
(11 Nm).
20. Reconnect the breather and evaporation hoses, as tagged during
removal.
21. Install the spark plugs.
22. Install the fuel pump, flywheel cover and lower engine covers as
detailed in the appropriate procedures.
23. Connect the negative battery cable, then connect a flushing device
and start the engine to check for oil leaks at the rocker arm cover mating
surfaces.
24. Install the engine top case.
1501175 tip Motors
See Figures 198 thru 200,206 thru 208, and 220 thru 223
The 1501175 hp motors utilize replaceable shims to adjust valve
clearance, A set of flat feeler gauges is all that is required to check valve
clearance. But, if adjustments are necessary, you will need a micrometer for
shim measurement, an assortment of shims (or a trip during the procedure to
purchase the proper size shims) and Suzuki #09916-69310 or an equivalent
tappet holder tool.
These motors are LH rotating. That is, they rotate
COUNTERCLOCKWISE when looking downward at the flywheel. DO
NOT turn them in the wrong direction, or you risk damaging the water
pump impeller vanes.
These motors utilize a dual overhead camshaft arrangement driven
by a timing chain and sprockets which are mounted at the BOTTOM of
the cylinder. As such, unless the powerhead has been removed for
repair, the timing marks on those sprockets are rather useless when it
comes to finding TDC and checking valve clearance. Instead, since the
camshafts are in plain site (once the cylinder head cover is removed)
use them to determine if a given cylinder is on TDC. Remember, the
intake valve will be the last to close, right about the time the piston
begins to travel back upwards. When the piston on any given cylinder
reaches the top of travel and BOTH the intake and exhaust valves for
that cylinder are closed, then the cylinder is at TDC.
Valve specifications are for an overnight cold engine. It is best to check
and/or adjust the valves with the powerhead at approximately 20% (68¡F)
1. For safety, disconnect the negative battery cable.
2. Remove the small protective cover that is over the fuel filter and the
bottom of the valve cover by gently grabbing and pulling the TOP OF THE
COVER OUTWARD and then lifting upward to free the cover from the
powerhead.
3. Remove the lower engine covers as described in this section.
4. Remove the air intake silencerlflywheel cover.
5. Remove the ignition coils and spark plugs as described in this
section.
6. Rotate the engine COUNTERCLOCKWISE to bring the No. 1
cylinder to TDC of the compression stroke and thereby relieving mechanical
pressure from the fuel pump arm. Remove the low pressure fuel pump from
the cylinder head cover as described in the Fuel System section.
7. Remove the 2 bolts securing the fuel filter bracket to the bottom of
the powerhead then remove the filter and bracket for clearance.
8. On 175 hp models, tag and disconnect the Intake Camshaft Position
Sensor (IN CMP) at the top starboard side of the cover. if necessary, loosen
the bolt and remove the sensor completely from the cover.
9. Tag and disconnect the Exhaust Camshaft Position Sensor (EX
CMP) at the top port side of the cover. If necessary, loosen the bolt and
remove the sensor completely from the cover.
10. Remove the bolt securing the wire clamp plate that is about halfway
down the valve cover on the starboard side.
11. Remove the bolt securing the wire clamp plate which is near the
bottom of the valve cover on the port side.
12. On 175 hp models, tag and disconnect the wiring from the Variable
Valve Timing (VVT) system Oil Control Valve (OCV) which is found at the
base of the powerhead head and valve cover on the starboard side, right
near the bottom of the fuel rail. Remove the 4 bolts securing the OCV
assembly, then remove the assembly and discard the old gasket.
13. Loosen and remove the 14 cylinder head cover bolts in the opposite
of the tightening sequence (basically by using a crossing pattern that starts
at the upper and lower ends of the valve cover and works inward).
14. Remove the cover along with the gasket assembly from the
powerhead. Be careful not to damage the cover gasket if you have any
intention of trying to reuse it. Inspect the gasket for damaged surfaces and
replace, if necessary.
@ Suzuki recommends replacing the valve cover gasket with integral
spark plug bore O-rings anytime the cover is removed.
15. Check that the flywheel is still in the No. 1 TDC position by making
sure the camshaft lobes face out and away from (meaning not pushing on)
the valve tappets for that cylinder. Insert feeler gauges of various sizes
between the tappet shim and the camshaft lobe. The size gauge that passes
between the shim and lobe with a slight drag indicates the valve clearance.
Record the clearance for each valve.
16. The firing order on this motor is 1-3-4-2, so the No. 3 cylinder should
come up to TDC next, followed by the No. 4 cylinder and the No. 2 cylinder
last, then the cycle will return back to the beginning of the firing order. Rotate
the flywheel counterclockwise until the No. 3 camshaft lobe tips are facing
out and opposite the valve tappets. Insert feeler gauges of various sizes
between the tappet shim and the camshaft lobe. The size gauge that passes
between the shim and lobe with a slight drag indicates the valve clearance.
Record the valve clearance for each valve.
17. Rotate the flywheel counterclockwise until the No. 4 camshaft lobe
tips are facing out and opposite the valve tappets. Insert feeler gauges of
various sizes between the tappet shim and the camshaft lobe. The size that
passes between the shim and lobe with a slight drag indicates the valve
clearance. Record the valve clearance for each valve.
18. Rotate the flywheel counterclockwise until the No. 2 camshaft lobe
tips are facing out and opposite the valve tappets. Insert feeler gauges of
VALVE COVER
TIGHTENING
SEQUENCE
VALVE COVER
LOOSENING
SEQUENCE
Fig. 220 Valve cover loosening and tightening sequences -1501175
hp motors
Fig. 221 Apply a light coating of Suzuki Bond No. 1207B to the
cylinder head at the gasket mating surfaces for the top and bottom
of the head
1
0.28 -0.32 223 225 228 230 233 235 238 240 243 245 248 2501253,255 258 260 263 265 268 270 273 275 278 280 283 285 288 290 293 295 298 300
0.33-0.37 228 230 233 235 238 240 243 245 248 250 253'255 258 260 263 265 268 270 273 275 278 280 283 285 288 290 293 295 298 300
'
0.38-0.42 233 235!238 240 243 245 248 250 253255258280/263265 26812701273 275 278 280 283 285 288 290 293 285 298 300
.-
0.43 -0.47 238 240 243 245 248 250 253 255 25s 2601263 265 268i270 273 275 278 280 283 285 288 290 293 295 298 300
0.48 -0.52 243 245 248 250 253 255 258 260 283 265 268 270 273 275 278 260 283 2851288 290 293 295 298 300
I
0.53 -0.57 248 250 253 255 258 260 263'285 268 270 273 275 278'280 283 285 288 290293 295 298 300
-----------3
0.58-0.62 253 255 258 260 263 265 268 270 273 275 278 280 2831285,288 290 293 295 298 300 I. Measure tappet clearance "Engine cold
2. Measure present shim size.
0.63 -0.67 258 260 283 265 268 270 273 275 278280 283 285 2881290 293 295 298 300
3. Match clearance in vertical column with
present shim size in horizontal column.
[ EXAMPLE ]
Tappet clearance is -0.35 mm
Present shim size -2.40 mm
Shim size to be used -2.50 mm
Fig. 222 Intake valve tappet shim selection chart -90/115/140 hp motors
TION CHART [EX. side]
1. Measure tappet clearance "Engine cold".
2. Measure present shim size.
3. Match clearance in vertical column with
present shim size In horizontal column.
[ EXAMPLE ]
Tappet clearance is -0.40 mm
Present shim size -2.40 mm
Shim size to be used -2.50 mm
Fia. 223 Exhaust valve tannet shim selection chart -90/115/140 ho motors
various sizes between the tappet shim and the camshaft lobe. The size that
passes between the shim and lobe with a slight drag indicates the valve
clearance. Record the valve clearance for each valve.
19. Compare the clearances with the Valve Clearance Specifications
chart in this section.
20. If incorrect valve clearance is noted, substitute the proper sized shim,
determined as follows:
a. If valve clearance is greater than spec, subtract the valve clearance
specification (using the dead middle of the range) listed in the specification
chart from the measured clearance. Obtain a replacement shim, that much
thicker than the current shim.
b. If valve clearance is less than specification, subtract the measured
clearance from the valve clearance specification (again, using the dead
middle of the range) listed in the chart. Obtain a replacement shim that much
smaller than the original.
Alternately you can use the accompanying shim selection charts
(one for Intake and one for Exhaust since the soecifications are
different for each) in order to choose the appropriate replacement shim.
For example, say you measured a clearance of 0.46mm for an intake
valve, and the current shim for that valve is a 2.40mm (marked 240).
First look down the left outer column to locate the row for 0.46mm (it is
the 10th row down, marked 0.43-0.47mm). Next look across the top for
the 240 shim (2.40mm), it is the 10th column over from the left. Follow
the column down to the point where it intersects with the 0.43-0.47mm
row and you'll find that the proper new shim would be marked 260 for
2.6mm. You can also tell from the chart that replacement shims are
available from 218 (2.18mm) to 300 (3.0mm) in varying increments of
either 0.02mm or 0.03mm.
21. If shim replacement is necessary to obtain the proper valve lash use
a bridge-type tappet holder tool (such as #09916-69310) as follows:
a. Rotate the flywheel counterclockwise until the camshaft lobe tip for
the selected valve is opposite the tappet (facing out, 180' away from the
tappet).
b. Carefully rotate the tappet within its bore until the notch is facing
toward the opposite camshaft (the center of the cylinder head). The notch
must be accessible for tappet shim removal.
c. Rotate the flywheel counterclockwise until the camshaft lobe tip
contacts the tappet shim (opening the valve and creating room for the tool).
Remove the bolts from the camshaft cap next to the selected valve.
d. Place the tappet retainer over the camshaft cap. In some cases, the
end of the retainer is marked either IN (for intake) or EX (for exhaust) and
the appropriate end must face inward toward the center of the cylinder head
(toward the notch on the tappet from which the shim will be removed).
Thread the camshaft cap bolts through the retainer and the camshaft cap.
Tighten the bolts securely, ensuring the fingers of the tool contact the barrel
portion of the tappet and not the shim itself.
e. Rotate the flywheel counterclockwise one half revolution or until the
camshaft lobe tip rotates 90' away from the tappet. Use a small magnet to
grab and remove the shim. If absolutely necessary, insert a screwdriver (with
tape covering the blade to prevent scoring or damage) into the tappet notch
and carefully pry the shim from the tappet, then use the magnet to pull the
shim from the tappet. DO NOT use your fingers.
DO NOT let your fingers get between the camshaft and tappet at any
time, as they could be crushed if the tool or camshaft suddenly shifted.
f. Measure the shim thickness using a micrometer. Shims are available
in sizes from 0.086-0.118 in. (2.18-3.0mm) in varying increments of either
0.00078 in. (0.02mm) or 0.00118 in (0.03mm). Select the correct shim
thickness as described earlier.
@ On new shims, the thickness can be identified by the number
present on the shim's face, divided by 100. Move the decimal point 2
places to the left and you've got your size. For example a new shim
labeled 258 on the face is 2.58mm thick. The label can only be trusted
on new shims, which have not been in service, as normal wear during
service might change shim thickness overtime.
g. Place the selected shim into the tappet with the numbered side
facing down TOWARD the tappet.
h. Make sure the shim seats fully against the step within the tappet,
then rotate the flywheel counterclockwise one half revolution or until the
camshaft lobe tip contacts the shim (pushing the tappet downward and
taking the load off the tappet holder tool so it can be safely removed. Loosen
and remove the bolts from the camshaft cap and tappet retainer.
i Carefully pull the retainer from the cap, then install camshaft cap bolts
and tighten evenly to 104.4 inch lbs.18.7 ft. Ibs. (12 Nm).
22. Repeat for each of the valves whose lash was noted out of
specification. Once you are finished with any shim changes, recheck the
clearance for that valve. And once you are finished with all valve clearance
checks, reset the powerhead to No. 1 TDC to ease fuel pump installation.
23. Install a new valve cover gasket with integral spark plug bore O-rings
on the underside mating surface of the valve cover.
24. Apply a light coating of Suzuki Bond No. 1207B or equivalent, to the
top and bottom horizontal lines of the cylinder head (along the gasket mating
surface).
25. Install the cover to the cylinder head making sure the spark plug port
O-rings are not dislodged when you are seating it, then install and tighten the
cover bolts using the torque sequence (which is essentially a crossing
pattern that starts at the center and works outward) to 96 inch lbs.18 ft. Ibs.
(11 Nm).
26. Reconnect the various wiring plates, components and wiring
connectors as tagged during removal (including the OCV valve on 175 hp
motors, using a NEW gasket positioned so the tab is at the upper bolt on the
port side and tighten the bolts to 104.4 inch lbs.18.7 ft. lbs.112 Nm, and be
sure to install the fuel filter assembly).
27. Install the spark plugs and the ignition coils.
28. Install the fuel pump, flywheel coverlair intake silencer and lower
engine covers as detailed in the appropriate procedures.
29. Install the protective cover over the fuel filter assembly and lower
portion of the valve cover.
30. Connect the negative battery cable, then connect a flushing device
and start the engine to check for oil leaks at the rocker arm cover mating
surfaces.
31. Install the engine top case.
200-300 Hp V6 Motors
See Figures 198 thru 200,206 thru 208, and 224 thru 227
The 200-300 hp V6 motors utilize replaceable shims to adjust valve
clearance. A set of flat feeler gauges is all that is required to check valve
clearance. But, if adjustments are necessary, you will need a micrometer for
shim measurement, an assortment of shims (or a trip during the procedure to
purchase the proper size shims) and Suzuki #09916-69310 or an equivalent
tappet holder tool.
These motors are LH rotating. That is, they rotate
COUNTERCLOCKWISE when looking downward at the flywheel. DO
NOT turn them in the wrong direction, or you risk damaging the water
pump impeller vanes.
These motors utilize a dual overhead camshaft arrangement driven
by a timing chain and sprockets which are mounted at the BOTTOM of
the cylinder. As such, unless the powerhead has been removed for
repair, the timing marks on those sprockets are rather useless when it
comes to finding TDC and checking valve clearance. Instead, since the
camshafts are in plain site (once the cylinder head cover is removed)
use them to determine if a given cylinder is on TDC. Actually, whether
or not the particular cylinder is on TDC is not important on these
motors, and there are enough valves/cylinders that trying to keep track
of that would be un-necessarily complicated. Instead, think only about
camshaft position. Check EACH valve only when the camshaft lobe is
facing directly AWAY (180') FROM the tappet. Rotate the crankshaft
COUNTERCLOCKWISE as necessary to rotate the camshafts, and
continue to check each valve in succession until you have checked
them all.
Valve specifications are for an overnight cold engine. It is best to check
and/or adjust the valves with the powerhead at approximateiy 2GCC\6SLF1.
1. For safety, disconnect the negative battery cable.
2. Remove the lower engine covers as described in this section.
3. Remove the ignition coils (as detailed in the Ignition and Electrical
System section) and the spark plugs (as detailed in this section).
4. Remove the air intake silencer/flywheel cover assembly, as detailed
in the Fuel System section.
5. On 200-250 hp motors, remove the collector assembly, as detailed
under Throttle Body and Intake Manifold Assemblies in the Fuel System
section.
6. Remove components from the port side cylinder head cover as
follows:
a. On 200-250 hp motors, tag and disconnect the wiring for the exhaust
manifold (EM) temperature sensor found on top of the cylinder bank, then
remove the nearly bolt for the wiring harness clamp plate. Also on these
models, tag and disconnect the wiring for the cylinder temperature (CT)
sensor, also on top of the cylinder bank, near the EM temp sensor connector.
b. On 250 and 300 hp motors, tag and disconnect the wiring for the
exhaust camshaft position sensor (EX CMP) and intake camshaft position
sensor (IN CMP), then remove the bolt securing the wire plate. These
sensors will be found on top of the cylinder bank.
c. On 300 hp motors, disconnect the PCV valve from the upper corner
of the cylinder head cover (right between the aforementioned camshaft
position sensors).
d. On 250 and 300 hp motors (which are the models which should be
equipped with Variable Valve TimingNVT), tag and disconnect the wiring at
the oil control valve (OCV) for the VVT which is found at the base of the
cylinder head cover. Remove the 4 bolts securing the valve to the cover,
then remove the valve and discard the gasket (but note the gasket tab
positioning before doing so).
e. On 300 hp motors there should be one more wire clamp plate to
remove, on the valve cover right above where the OCV assembly mounts.
7. Remove components from the starboard side cylinder head cover as
follows:
a. On 200-250 hp motors, tag and disconnect the wiring for the exhaust
manifold (EM) temperature sensor found on top of the cylinder head cover.
b. On all models, tag and disconnect the wiring from the intake
camshaft position sensor (IN CMP) found at the top corner of the cylinder
head cover, then remove the wire clamp bolt found at the top center of the
cylinder head cover.
c. On 250 and 300 hp motors, tag and disconnect the wiring at the oil
control valve (OCV) which is found at the base of the cylinder head cover.
Remove the 4 bolts securing the valve to the cover, then remove the valve
and discard the gasket (but note the gasket tab positioning before doing so).
d. On 300 hp motors there should be one more wire clamp plate to
remove, on the valve cover a little above where the OCV assembly mounts.
8. Remove the port and starboard cylinder head covers by loosening
the 11 bolts on each cover using the reverse of the torque sequence (which
basically makes for a crossing pattern that starts at the upper and lower
ends of the cover and works its way inward).
9. Remove the cover along with the gasket assembly from the
powerhead. Be careful not to damage the cover gasket or integral spark plug
O-rings if you have any intention of trying to reuse it. Inspect the gasket for
damaged surfaces and replace, if necessary.
Suzuki recommends replacing the valve cover gasket with integral
spark plug bore O-rings anytime the cover is removed.
10. Rotate the engine COUNTERCLOCKWISE to bring each camshaft
and tappet you wish to check into a position where the camshaft lobe is
facing DIRECTLY opposite (away from, as in "not pressing on") the valve
tappet. Insert feeler gauges of various sizes between the tappet shim and
the camshaft lobe. The size gauge that passes between the shim and lobe
with a slight drag indicates the valve clearance. Record the clearance for that
valve, then rotate the crankshaft COUNTERCLOCKWISE as necessary to
rotate the camshafts, and continue to check each valve in succession until
you have checked and recorded them all.
@ There are a LOT of valves on this motor, don't confuse yourself,
make up a little chart/diagram showing the name (Intake or Exhaust
and cylinder number or number from top) for each bank as represented
by positions in a rectangular box that correspond to the actual position
of each valve, then fill in the measured values on the diagram as you
go. This will make it much harder to confuse yourself, record the wrong
value or forget to check one or more of the valves.
11. Compare the clearances with the Valve Clearance Specifications
chart in this section.
12. If incorrect valve clearance is noted, substitute the proper sized shim,
determined as follows:
a. If valve clearance is greater than spec, subtract the valve clearance
specification (using the dead middle of the range) listed in the specification
chart from the measured clearance. Obtain a replacement shim, that much
thicker than the current shim.
b. If valve clearance is less than specification, subtract the measured
clearance from the valve clearance specification (again, using the dead
middle of the ranae) listed in the chart. Obtain a reolacement shim that much
smaller than the original.
B Alternately you can use the accompanying shim selection charts in
order to choose the appropriate replacement shim. For example, say
you measured a clearance of 0.46mm on an intake valve, and the
current shim is a 2.60mm (marked 260). First look down the left outer
column to locate the row for 0.46mm (it is the 10th row down, marked
0.43-0.47mm). Next look across the top for the 260 shim (2.60mm), it is
the 18th column over from the left. Follow the column down to the
point where it intersects with the 0.43-0.47mm row and you'll find that
the proper new shim would be marked 280 for 2.8mm. You can also tell
from the chart that replacement shims are available from 218 (2.18mm)
to 300 (3.0mm) in varying increments of either 0.02mm or 0.03mm.
13. If shim replacement is necessary to obtain the proper valve lash use
a bridge-type tappet holder tool (such as #09916-69310) as follows:
a. Rotate the flywheel counterclockwise until the camshaft lobe tip for
the selected valve is opposite the tappet (facing out, 180' away from the
tappet).
Apply a light coating of Suzuki Bond No. 1207B to the
Fig. 224 Port and Starboard valve cover torque sequences -200-head at the gasket mating surfaces at the bottom of each
300 hp V6 motors
1. Measure tappet clearance "Engine cold.
2. Measure present shim size.
3. Match clearance in vertical column with
present shim size in horizontal column.
[ EXAMPLE ]
Tappet clearance is -0.35 rnm
Present shim size -2.40 rnm
Shim size to be used -2.50 rnrn
Fig. 226 Intake valve tappet shim selection chart -200-300 hp V6 motors
255258 260 2631265 268 270 273 275 278 980 283 285 288 290
1 -1 293p J298pl
260 263 285 2681270 273 275 278 280 283 285 288 290 293 295 298300 I. Measure tappet clearance "Engine cold"
0.65 -0.69 I250 2531255 258 2601263 265 268 270 2731275 278 260'283 285 288 280293 295 296 300
2. Measure present shim size.
3. Match clearance in vertical column with
0.70-0.74 255 25a1260 26312652.58 270 273 275 278280 283 285 288 290293 295 298 300 present shim size in horizontal column.
[ EXAMPLE]
Tappet clearance is -0.40 mm
Present shim size -2.40 rnrn
Shim size to be used -2.48 mm
=ig.227 Exhaust valve tappet shim selection chart -200-300 hp V6 motors
b. Carefully rotate the tappet within its bore until the notch is facing
toward the opposite camshaft (the center of the cylinder head). The notch
must be accessible for tappet shim removal.
c. Rotate the flywheel counterclockwise until the camshaft lobe tip
contacts the tappet shim (opening the valve and creating room for the tool).
Remove the bolts from the camshaft cap next to the selected valve.
d. Place the tappet retainer over the camshaft cap. In some cases, the
end of the retainer is marked either IN (for intake) or EX (for exhaust) and
the appropriate end must face inward toward the center of the cylinder head
(toward the notch on the tappet from which the shim will be removed).
Thread the camshaft cap bolts through the retainer and the camshaft cap.
Tighten the bolts securely, ensuring the fingers of the tool contact the barrel
portion of the tappet and not the shim itself.
e. Rotate the flywheel counterclockwise one half revolution or until the
camshaft lobe tip rotates 90Â away from the tappet. Use a small magnet to
grab and remove the shim. If absolutely necessary, insert a screwdriver (with
tape covering the blade to prevent scoring or damage) into the tappet notch
and carefully pry the shim from the tappet, then use the magnet to pull the
shim from the tappet. DO NOT use your fingers.
DO NOT let your fingers get between the camshaft and tappet at any
time, as they could be crushed if the tool or camshaft suddenly shifted.
f. Measure the shim thickness using a micrometer. Shims are available
in sizes from 0.086-0.118 in. (2.18-3.0mm) in varying increments of either
0.00078 in. (0.02mm) or 0.00118 in (0.03mm). Select the correct shim
thickness as described earlier.
W On new shims, the thickness can be identified by the number
present on the shim's face, divided by 100. Move the decimal point 2
places to the left and you've got your size. For example a new shim
labeled 258 on the face is 2.58mm thick. The label can only be trusted
on new shims, which have not been in service, as normal wear during
service might change shim thickness overtime.
See Figure 228
Taking extra time to store the boat and motor properly at the end of each
season or before any extended period of storage will greatly increase the
chances of satisfactory service at the next season. Remember, that next to
hard use on the water, the time spent in storage can be the greatest enemy
of an outboard motor. Ideally, outboards should be used regularly. If weather
in your area allows it, don't store the motor, enjoy it. Use it, at least on a
monthly basis. It's best to enjoy and service the boat's steering and shifting
mechanism several times each month. If a small amount of time is spent in
such maintenance, the reward will be satisfactory performance, increased
longevity and greatly reduced maintenance expenses.
But, in many cases, weather or other factors will interfere with time
for enjoying a boat and motor. If you must place them in storage, take
time to properly winterize the boat and outboard. This will be your best
shot at making time stand still for them.
For many years there was a widespread belief simply shutting off the fuel
at the tank and then running the powerhead until it stops constituted
prepping the motor for storage. Right? Well, WRONG!
First, it is not possible to remove all fuel in the carburetor or fuel injection
system by operating the powerhead until it stops. Considerable fuel will
remain trapped in the float chamber and other passages, especially in the
lines leading to carburetors. The only guaranteed method of removing all fuel
is to take the physically drain the carburetors from the float bowls. On EFI
systems, disassemblin~ the fuel injection components to drain the fuel is
impractical (and really not necessary) so properly mixing fuel stabilizer
becomes that much more imoortant. Actually, these days most
manufacturers recommend prepping their motors (even carbureted) using
g. Place the selected shim into the tappet with the numbered side
facing down TOWARD the tappet.
h. Make sure the shim seats fully against the step within the tappet,
then rotate the flywheel counterclockwise one half revolution or until the
camshaft lobe tip contacts the shim (pushing the tappet downward and
taking the load off the tappet holder tool so it can be safely removed. Loosen
and remove the bolts from the camshaft cap and tappet retainer.
i Carefully pull the retainer from the cap, then install camshaft cap bolts
and tighten evenly to 104.4 inch lbs.18.7 ft. Ibs. (12 Nm).
14. Repeat for each of the valves whose lash was noted out of
specification. Once you are finished with any shim changes, recheck the
clearance for that valve.
15. Install the port and starboard cylinder head covers using a new
gasket. Before installation, apply a light coating of Suzuki Bond No. 1207B to
the cylinder head at the gasket mating surfaces at the bottom of each head.
Coat the head-to-cover gasket mating surface from the lower cover retaining
bolt web on one side, all the way across and up to the lower bolt web on the
other side of the head.
One some models (like the 300 hp motors) the port side cylinder
head uses a dowel pin right above and slightly to the side of the top
spark plug port. If used, make sure any dowel pins are In position
before the cover is installed.
16. Install the valve cover retaining bolts and tighten using the proper
torque sequence (a crossing pattern that starts and the center and works
outward) to 104.4 inch lbs.18.7 ft. Ibs. (12 Nm) on 200-250 hp motors or to 96
inch lbs.18 ft. Ibs. (11 Nm) on 300 hp motors.
17. Install the wiring, wire retainer plates and any other components that
were removed from the valve cover assemblies. On 250 and 300 hp motors
(i.e. any models with VVT), install the OCV assembly to the base of each
valve cover using a new gasket. MAKE SURE to position the gasket so the
tab is at the upper left side bolt when looking at the valve cover. Tighten the
OCV retaining bolts to 104.4 inch lbs.18.7 ft. Ibs. (12 Nm).
18. On 200-250 hp motors, install the collector assembly.
19. Install air intake silencer and flywheel cover assembly.
20. Install the spark plugs and ignition coils.
21. Connect the negative battery cable, then connect a flushing device
and start the engine to check for oil leaks at the rocker arm cover mating
surfaces.
22. install the engine top case.
Fig. 228 Add fuel stabilizer to the system anytime it will be stored
without complete draining
fuel stabilizer as opposed to draining the fuel system, but on carbureted
motors, you always have the option.
Proper storage involves adequate protection of the unit from physical
damage, rust, corrosion and dirt. The following steps provide an adequate
maintenance program for storing the unit at the end of a season.
PREPPING FOR STORAGE
Where to Store Your Boat and Motor
Ok, a well lit, locked, heated garage and work area is the best place to
store you precious boat and motor, right? Well, we're probably not the only
ones who wish we had access to a place like that, but if you're like most of
us, we place our boat and motor wherever we can.
Of course, no matter what storage limitations are placed by where you
live or how much space you have available, there are ways to maximize the
storage site.
If possible, select an area that is dry. Covered is great, even if it is under
a carport or sturdy portable structure designed for off-season storage. Many
people utilize canvas and metal frame structures for such purposes. If you've
got room in a garage or shed, that's even better. If you've got a heated
garage, God bless you, when can we come over? If you do have a garage or
shed that's not heated, an insulated area will help minimize the more
extreme temperature variations and an attached garage is usually better than
a detached for this reason. Just take extra care to make sure you've properly
inspected the fuel system before leaving your boat in an attached garage for
any amount of time.
If a storage area contains large windows, mask them to keep sunlight off
the boat and motor otherwise, use a high-quality, canvas cover over the
boat, motor and if possible, the trailer too. A breathable cover is best to avoid
the possible build-up of mold or mildew, but a heavy duty, non-breathable
cover will work too. If using a non-breathable cover, place wooden blocks or
length's of 2 x 4 under various reinforced spots in the cover to hold it up off
the boat's surface. This should provide enough room for air to circulate under
the cover, allowing for moisture to evaporate and escape.
Whenever possible, avoid storing your boat in industrial buildings or parks
areas where corrosive emissions may be present. The same goes for storing
your boat too close to large bodies of saltwater. Hey, on the other hand, if
you live in the Florida Keys, we're jealous again, just enjoy it and service the
boat often to prevent corrosion from causing damage.
Finally, when picking a place to store your motor, consider the risk or
damage from fire, vandalism or even theft. Check with your insurance agent
regarding coverage while the boat and motor is stored.
The Great Ethanol Debate
As of this authoring, ethanol has been in use around the US and in
various places in the world for quite some time. Truth is that decades ago
manufacturers made changes to most fuel system components to make
them less or non-susceotible to the affects of alcohol. HOWEVER. in late
2005learly 2006 when Ethanol was suddenly introduced to large areas of the
US where it had previously been absent, a few new problems were noted.
Ethanol can act like a solvent and in doing so it can clean away deposits
in a fuel system that had previously hardened and stuck to component. The
biggest concern would be for large fuel supplies (like fuel tanks) where a
repeated pattern of evaporation over the years allowed large amounts of
deposits to stick to component walls. Suddenly introducing ethanol to this
environment, and allowing it to sit in the tank over a winter or longer, gives it
time to reconstitute many of these deposits in a manner that they can be
drawn into the fuel supply when the motor is taken out of storage, clogging
filters or worse, contaminating carburetors or injection systems. Ethanol
hasn't seemed to cause this problem in markets where it has already been
common for long periods of time and the thought is that it's constant use
over the years have prevented deposits from sticking (literally) around.
Basically the Ethanol was essentially scrubbing the fuel systems clean in
those markets, keeping them from developing enough deposits to clog the
system all at once.
There is a potential enzymatic solution to ethanol cleaning old fuel
tanks and creating sludge/particulates in the form of a fuel treatment
from Starbrite called StarTron. Pur~ortedlv StarTron was develo~ed in
Japan for use in extremely high-volume industrial equipment that could
not economically be shut down in order to replace filters. As such, it
uses enzymes to break down the particulates to a size small enough to
not only pass through filters, but to harmlessly pass through
carburetors or injectors for burning. Though we haven't personally
tested this product yet, it comes with high recommendations from a
company in which we have some faith, so we are optimistic.
Also a problem is the fact that Ethanol can attack and break down the
resins used to make Fiberglass Reinforced Plastic (FRP) gas tanks, both
creating contaminated fueland causing a weakening of the tank structure
which can lead to leaks. Similarly. Ethanol will. over time, SLOWLY corrode
an aluminum tank leading to leaks as well. If a boat you are storing contains
an FRP tank and only Ethanol fuel is available in your area, you are going to
have to look into replacing the tank and you should probably consider doing
this before it becomes a problem.
NOT ALL plastic tanks are made of FRP, so don't go replacing a tank
until you talk to the boatltank manufacturer to confirm the materials
used on the boatltank in question.
For aluminum tanks, we'd recommend storing the tank as empty to greatly
reduce the amount of time that the tank is exposed to ethanol (basically,
don't give it all winter to allow the ethanol to slowly attack the tank structure).
Another potential problem with Ethanol is that it has the unique ability
(compared to other additives found in fuel) to bond with both fuel and water.
The result is that where water would normally sit separate from the fuel in a
contaminated system (where the water and fuel could be drawn off
individually), water will instead mix with fuel containing ethanol which can
lead to a greatly reduced ability to support combustion (to the point where an
engine cannot run).
In the past we've recommended that it was a wash (six of one, half a
dozen of the other) whether or not you stored your fuel tank FULL or EMPTY
with regards to the amount of moisture that might enter the system from
condensation. However, that was when the moisture might be drawn off from
a full tank IF it got that bad. We don't think people are as willing today to risk
20, 50 or 100 gallons of fuel become contaminated with water and have
changed our position. We think it is probably smarter to store the fuel tank as
EMPTY as possible, and then in spring prior to refilling the tank to use a
siphon or primer bulb to draw off any water which has condensed over the
storage period.
Of course, these are the best current recommendations that we can offer,
and this is likely a rapidly changing topic, so we also recommend asking
around for other recommendations and solutions as time continues to go by.
Storage Checklist (Preparing the Boat and Motor)
See Figures 228 thru 232
The amount of time spent and number of steps followed in the storage
procedure will vary with factors such as the length of planed storage time,
the conditions under which boat and motor are to be stored and your
personal decisions regarding storage.
But, even considering the variables, plans can chanae (we know this from
personal experience), so be careful if you decide to perform only the minimal
amount of oreoaration. A boat and motor that has been thorouohlv oreoared
" , 0
L
for storagecab remain so with minimum adverse affects for as short or long
a time as is reasonably necessary. The same cannot be said for a boat or
motor on which important winterization steps were skipped.
B Always store a Suzuki motor vertically on the boat or on a suitable
engine stand. Do not lay a 4-stroke motor down for any length of time,
as engine oil may seep past the rings causing extreme smoking upon
startup. At best, burning that oil will promote spark plug and
combustion chamber fouling, at worst it could cause a partial hydro-
lock condition that could even mechanically damage the powerhead.
A few words about fuel treatment
a Using fuel stabilizer toward the end of the season is probably one of
the best things you can do to pre-prepare for storage. As your season
draws to a close begin adding fuel stabilizer to the tank with every fill-
up and you'll be part way there when it comes time to winterize,
1. Thoroughly wash the boat motor and hull. Be sure to remove all
traces of dirt, debris or marine life. Check the water stream fitting and water
inlet(s). If equipped, inspect the speedometer opening at the leading edge oi
the gearcase or any other gearcase drains for debris (clean debris with a
compressed air or a piece of thin wire).
2. Stabilize the engine's fuel supply using a high quality fuel stabilizer
and take this opportunity to thoroughly flush the engine cooling system at the
same time as follows:
a. For ALL motors follow the instructions on the fuel conditioner and
add an appropriate amount of fuel treatment for the amount of fuel in the fuel
tank or being added to the fuel tank. (Or hopefully, you've already done this
by using the treatment regularly toward the end of season, and if so you may
not need to add anymore at this time).
b. Attach a flushing fitting as a cooling water/flushing source. For
details, please refer to the information on Flushing the Cooling System, in
this section.
c. Start and run the enaine at a fast idle for a~oroximatelv 5 minutes on
30 hp and smaller models orat least 10 minutes o'i40 hp and larger
models. This will ensure the entire fuel supply system contains the
appropriate storage mixtures.
d. Stop the engine, keeping the outboard perfectly vertical. Allow the
cooling system to drain completely, especially if the outboard might be
exposed to freezing temperatures during storage. Leave the flush fitting in
place since you will need to run the motor again for fogging andlor to
distribute fresh engine oil after it is changed.
Fig. 229 Flush the motor. ..
NEVER keep the outboard tilted when storing in below-freezing
temperatures as water could remain trapped in the cooling system. Any
water left in cooling passages might freeze and could cause severe
engine damage by cracking the powerhead or gearcase.
3. Drain and refill the engine gearcase while the oil is still warm (for
details, refer to the Gearcase Oil procedures in this section). Take the
opportunity to inspect for problems now, as storage time should allow you
the opportunity to replace damaged or defective seals. More importantly,
remove the old, contaminated gear oil now and place the motor into storage
with fresh oil to help prevent internal corrosion.
4. Drain the engine crankcase oil while it is still warm. Replace the oil
filter. Refill the crankcase and gearcase with fresh oil (for details, refer to the
Oil and Filter Change procedures in this section). On any motor that you do
not plan on running for fogging, start and run the motor again, but only for a
few minutes to evenly distribute the fresh oil across internal bearing
surfaces.
Besides treating the fuel system to prevent evaporation or clogging
from deposits left behind, coating all bearing surfaces in the motor with
FRESH, clean oil is the most important step you can take to protect the
engine from damage during storage. NEVER leave the engine filled with
used oil, which likely contains moisture and acids or other damaging
byproducts of combustion that will damage engine bearings over time.
5. Fog the motors using one of the following methods (as desired):
a. The engine can be fogged by spraying the can of fogging oil either
down the carburetor or throttle body throat(s) while the motor is running.
Although this method is relatively affective, especially for single carblthrottle
body motors, it can be difficult to do properly on multi-cylinder, multi-
carburetorlthrottle body units (unless you have a couple of extra hands and
one can of spray per throat). If desired, make sure the cooling water source
is connected, then follow the instructions on the can of fogging oil. Usually
you run the motor at idle and spray heavily in to the throat(s) until you either
shut the motor off or the oil causes it to choke and die on its own. BE
CAREFUL with spray cans that use a small plastic applicator tube, don't
blow the tube off and down into the carblthrottle body.
Even if a motor is fogged while running, it is a good idea to follow
the steps of the non-running fogging procedure JUST to be certain
you've thoroughly protected the cylinders. Actually, a combination of
both methods is desired, as spraying through the carb or throttle body
will coat the intake passages, and spraying directly into the cylinders
will make sure all surfaces in the combustion chamber are coated.
Better safe than seized, we always say!
Fia. 230 . . .and on most models it's a aood
idea to manually fog it through the spark Fig. 231 For all motors, store vertically so Fig. 232 If possible, block up the trailer
plug ports the cooling system drains during storage
I I
b. To fog the cylinders directly through the spark plug ports, remove the
spark plugs as described earlier in this section. Spray a generous amount of
fogging oil into the spark plug ports. Turn the flywheel slowly by hand (in the
normal direction of rotation which is Clockwise on most models, EXCEPT the
left-hand rotation motors covered here, which are the 90-300 hp motors,
which normally rotate Counterclockwise) to distribute the fogging oil evenly
across the cylinder walls. On electric start models, the starter can be used to
crank the motor over in a few short bursts, but make sure the spark plugs
leads remain disconnected and grounded to the powerhead (away from the
spark plug ports) to prevent accidental combustion (on EFI cranking is not
really the best idea, since unless the fuel pump is disabled the injectors will
spray fuel, washing away some of the fogging oil). If necessary, re-spray into
each cylinder when that cylinder's piston reaches the bottom of its travel.
Reinstall and tighten the spark plugs, but leave the leads disconnected to
prevent further attempts at starting until the motor is ready for re-
commissioning.
On motors equipped with a rope start handle, the rope can be used
to turn the motor slowly and carefully using the rope starter. For other
models, turn the flywheel by hand or using a suitable tool, but be sure
to ALWAYS turn the engine in the normal direction of rotation.
6. For models equipped with portable fuel tanks, disconnect and
relocate them to a safe, well-ventilated, storage area, away from the motor.
Drain any fuel lines that remain attached to the tank.
7. Remove the battery or batteries from the boat and store in a cool dry
place. If possible, place the battery on a smart charger or Battery Tender(r),
otherwise, trickle charge the battery once a month to maintain proper charge.
Remember that the electrolyte in a discharged battery has a much
lower freezing point and is more likely to freeze (crackingldestroying
the battery case) when stored for long periods in areas exposed to
freezing temperatures. Although keeping the battery charged offers one
level or protection against freezing; the other is to store the battery in a
heated or protected storage area.
8. For models equipped with a boat mounted fuel filter or filterlwater
canister, clean or replace the boat mounted fuel filter at this time. If the fuel
system was treated, the engine mounted fuel filters should be left intact, so
the sealed system remains filled with treated fuel during the storage period.
9. For any motors equipped with a gearcase speedometer pickup,
disconnect the speedometer hose from the upper most connector (usually up
near the lower engine cowling, where the cables/hoses pass through into the
cowling) and blow all water from the gearcase speedometer pickup. If
compressed air is available, use less than 25 psi (167 kPa) of air pressure in
order to prevent damage to the system.
10. Perform a complete lubrication service following the procedures in
this section.
11. Remove the propeller and check thoroughly for damage. Clean the
propeller shaft and apply a protective coating of grease. Refer to the
procedure in this section.
12. Check the motor for loose, broken or missing fasteners. Tighten
fasteners and, again, use the storage time to make any necessary repairs.
13. Inspect and repair all electrical wiring and connections at this time.
Make sure nothing was damaged during the season's use. Repair any loose
connectors or any wires with broken, cracked or otherwise damaged
insulation.
14. Clean all components under the engine CGvci and apply a corrosion
preventative spray.
15. Too many people forget the boat and trailer, don't be one of them.
a. Coat the boat and outside painted surfaces of the motor with a fresh
coating of wax, then cover it with a breathable cover
b. If possible place the trailer on stands or blocks so the wheels are
supported off the ground.
c. Check the air pressure in the trailer tires. If it hasn't been done in a
while, remove the wheels to clean and repack the wheel bearings.
16. Sleep well, since you know that your baby will be ready for you come
next season.
REMOVAL FROM STORAGE
SY
See Figures 233,234 and 235
The amount of service required when re-commissioning the boat and
motor after storage depends on the length of non-use, the thoroughness of
the storage procedures and the storage conditions.
At minimum, a thorough spring or pre-season tune-up and a full
lubrication service is essential to getting the most out of your engine. If the
engine has been properly winterized, it is usually no problem to get it in top
running condition again in the springtime. If the engine has just been put in
the garage and forgotten for the winter, then it is doubly important to perform
a complete tune-up before putting the engine back into service. If you have
ever been stranded on the water because your engine has died and you had
to suffer the embarrassment of having to be towed back to the marina you
know how it can be a miserable experience. Now is the time to prevent that
from occurring.
Take the opportunity to perform any annual maintenance procedures that
were not conducted immediately prior to placing the motor into storage. If the
motor was stored for more than one off-season, pay special attention to
inspection procedures, especially those regarding hoses and fittings. Check
the engine gear oil for excessive moisture contamination. The same goes for
engine crankcase oil. If not done before storage or if the motor has been in
storage too long (read that as more than one winter), change the gearcase
or engine oil to be certain no bad or contaminated fluids are used.
Although not absolutely necessary, it is a good idea to ensure
optimum cooling system operation by replacing the water pump
impeller at this time.
Other items that require attention include:
1. Install the battery (or batteries) if so equipped.
2. Inspect all wiring and electrical connections. Rodents have a knack
for feasting on wiring harness insulation over the winter. If any signs of
Fig. 235 We know you're anxious to enjoy
the weather, but don't rush and forget
Fig. 233 Start and test run the motor Fig. 234 DON'T FORGET THE PLUG! something important
rodent life are found, check the wiring carefully for damage, do not start the
motor until damaged wiring has been fixed or replaced.
3. If not done when placing the motor into storage clean and/or replace
the fuel filters at this time. This is usually the case on EFI motors, as the
filters are often not replaced before filling the system with the storage fuel
mixture.
4. If the fuel tank was emptied, or if it must be emptied because the fuel
is stale check and make sure it doesn't contain any water (if necessary
siphon any water out), then fill the tank with fresh fuel. Keep in mind that
even fuel that was treated with stabilizer will eventually become stale,
especially if the tank is stored for more than one off-season. Pump the
primer bulb and check for fuel leakage or flooding at the carburetor or vapor
separator tank. For EFI motors, pressurize the high pressure fuel circuit
Unfortunately, because an outboard is mounted on the exposed transom
of a boat, and many of the outboards covered here are portable units that
are mounted and removed on a regular basis, an outboard can fall
overboard. Ok, it's relatively rare, but it happens often enough to warrant
some coverage here. The best way to deal with such a situation is to prevent
it, by keeping a watchful eye on the engine mounting hardware (bolts and/or
clamps). But, should it occur, here's how to salvage, service and enjoy the
motor again.
In order to prevent severe damage, be sure to recover an engine that is
dropped overboard or otherwise completely submerged as soon as possible.
It is really best to recover it immediately. But, keep in mind that once a
submerged motor is recovered exposure to the atmosphere will allow
corrosion to begin etching highly polished bearing surfaces of the crankshaft,
connecting rods and bearings. For this reason, not only do you have to
recover it right away, but you should service it right away too. Make sure the
motor is serviced within 3 hours of initial submersion.
OK, maybe now you're saying "3 hours, it will take me that long to get it to
a shop or to my own garage." Well, if the engine cannot be serviced
immediately (or sufficiently serviced so it can be started), re-submerge it in a
tank of fresh water to minimize exposure to the atmosphere and slow the
corrosion process. Even if you do this, do not delay any more than
absolutely necessary, service the engine as soon as possible. This is
especially important if the engine was submerged in salt, brackish or polluted
water as even submersion in fresh water will not preserve the engine
indefinitely. Service the engine, at the MOST within a few days of protective
submersion.
After the engine is recovered, vigorously wash all debris from the engine
using pressurized freshwater.
If the engine was submerged while still running, there is a good
chance of internal damage (such as a bent connecting rod). Under
these circumstances, don't start the motor, follow the beginning of this
procedure to try turning it over slowly by hand, feeling for mechanical
problems. If necessary, refer to Powerhead Overhaul for complete
disassembly and repair instructions.
R try to start a recovered motor until at least the first few steps
nes dealing with draining the motor and checking to see it if is
hydro-locked or damaged) are performed. Keep in mind that attempting
to start a hydro-locked motor could cause major damage to the
If the motor was submerged for any length of time it should be thoroughly
disassembled and cleaned. Of course, this depends on whether water
intruded into the motor or not. To determine this check the crankcase oil (on
4-strokes), and check the gearcase oil (on all motors) for signs of
contamination.
turning the ignition on (and listening to verify that the fuel pump runs for a
few seconds). Inspect the fuel rail and fittings under the engine top case for
leaks.
5. Attach a flush device or place the outboard in a test tank and start
the engine. Run the engine at idle speed and warm it to normal operating
temperature. Check for proper operation of the cooling, electrical and
warning systems.
Before putting the boat in the water, take time to verify the drain plug is
installed. Countless number of spring boating excursions have had a
very sad beginning because the boat was eased into the water only to
have the boat begin to fill with it.
The extent of cleaning and disassembly that must take place depends
also on the tvue of water in which the enaine was submeraed. Enaines
totally submerged, for even a short length of time, in salt, brackishor
polluted water will require more thorough servicing than ones submerged in
fresh water for the same length of time. But, as the total length of submerged
time or time before service increases, even engines submerged in fresh
water will require more attention. Complete powerhead disassembly and
inspection is required when sand, silt or other gritty material is found inside
the engine cover.
Many engine components suffer the corrosive effects of submersion in
salt, brackish or polluted water. The symptoms may not occur for some time
after the event. Salt crystals will form in areas of the engine and promote
significant corrosion.
Electrical components should be dried and cleaned or replaced, as
necessary. If the motor was submerged in salt water, the wire harness and
connections are usually affected in a shorter amount of time. Since it is
difficult (or nearly impossible) to remove the salt crystals from the wiring
connectors, it is best to replace the wire harness and clean all electrical
component connections. The starter motor, relays and switches on the
engine usually fail if not thoroughly cleaned or replaced.
To ensure a thorough cleaning and inspection:
1. Remove the enaine cover and wash all material from the enaine
using pressurized freshwater. If sand, silt or gritty material is present inside
the engine cover, completely disassemble and inspect the powerhead.
2. Tag (except on single cylinder motors) and disconnect the spark
plugs leads. Be sure to grasp the spark plug cap and not the wire, then twist
the cap while pulling upward to free it from the plug. Remove the spark
plugs. For more details, refer to the Spark Plug procedure in this section.
3. Disconnect the fuel supply line from the engine, then drain and clean
all fuel lines. Depending on the circumstances surrounding the submersion,
inspect the fuel tank for contamination and drain, if necessary.
When attempting to turn the flywheel for the first time after the
submersion, be sure to turn it SLOWLY, feeling for sticking or binding
that could indicate internal damage from hydro-lock. This is a concern,
especially if the engine was cranked before the spark plug(s) were
removed to drain water or if the engine was submerged while still
running.
4. Support the engine horizontally with the spark plug port(s) facing
downward, allowing water, if present, to drain. Force any remaining the water
out by slowly rotating the flywheel by hand about 20 times or until there are
no signs of water. If there signs of water are present, spray some fogging oil
into the spark plug ports before turning the flywheel. This will help dislodge
moisture and lubricate the cylinder walls.
5. On carbureted models, drain the carburetor(s). The best method to
thoroughly drainlclean the carburetor is to remove and disassemble it. For
details refer to the Carburetor procedures under Fuel System.
-84 MAINT
6. Support the engine in the normal upright position. Check the engine
aearcase oil for contamination. Refer to the urocedures for Gearcase Oil in
this section. The gearcase is sealed and, if the seals are in good condition,
should have survived the submersion without contamination. But, if
contamination is found, look for possible leaks in the seals, then drain the
gearcase and make the necessary repairs before refilling it. For more details,
refer to the section on Gearcases.
7. Drain the crankcase engine oil and change the filter. Refer to the
procedures in this section. if contaminated oil drains from the crankcase,
flush the crankcase using a quart or two of fresh four-stroke engine oil (by
pouring it into the motor as normal, but allowing it to drain as well) before
refilling the crankcase.
8. Remove all external electrical components for disassembly and
cleaning. Spray all connectors with electrical contact cleaner, then apply a
small amount of dielectric grease prior to reconnection to help prevent
corrosion. For electric start models, remove, disassemble and clean the
starter components. For details on the electrical system components, refer to
the Ignition and Electrical section.
9. Reassemble the motor and mount the engine or place it in a test
tank. Start and run the engine for 112 hour. If the engine won't start, remove
the spark plugs again and check for signs of moisture on the tips. If
necessary, use compressed air to clean moisture from the electrodes or
replace the plugs.
10. Stop the engine, then recheck the gearcase oil and engine crankcase
oil.
11. Perform all other lubrication services.
12. Try not to let it get away from you (or anyone else) again!
1bc: 1 barrel carburetor
AH: Amp Hours MC: Manual Choke
ECU Cont: Fully transistorized, ECU controlled, battery powered ignition NA: Not applicable
ECU Cont Dl: Fully transistorized, ECU controlled, directignition NR: Non-Regulated (equipped with rectifier)
EFI: Electronic Fuel Injection R: Rope (normally tiller equipped)
EP: Electric or automatic Primer (or choke) RE: Remote Electric Start
FR: Fully-Regulated (equipped with regulatorlrectifier) TC: Thermostatically controlled
IMP: Impeller pump TE: Tiller Electric Start
Mag CD: Magneto Powered Capacitor Discharge UG: Upper gearcase mounted
@ The most common, referenced charging system (may be optional on some models, rating shown is minimum)
@ Optional
@ Optional 120 watt coil available
2.5 I 1 I 2006-07 I 4.2 (68) 12.8 fl. OZ. (380 mL) I 2.0 (60)
8 . . , 1,
4 I 1 I 2002-07 I 8.4 (138) I 24 ft. oz (700 mL) I 6.4 (190)
5 1 1 1 2002-07 1 8.4 (138) I 24 ft. oz (700 mL) 1 6.4 (1 90)
140 I 4 I 2002-07 1 125 (2044) I 6.0 qt. (5.7 L) 1 35.5 (1050)
150 I 4 1 2006-07 1 175 (2867) 1 9.0 at. (8.5 L) 1 37.2 (1100)
. .
175 1 4 I 2006-07 1 1 9.0 at. (8.5 L) I 37.2 (1 100)
u -
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C SK
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g g .g .g .g .g
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COCOCOCOCOCO
0 MAINTENANCE AND TUN
AIR INTAKE SILENCER ..................3.90
REMOVAL& INSTALLATION .............3.90
CAMSHAFT POSITION (CMP) SENSOR ....3.121
REMOVAL& INSTALLATION ............3.123
TESTING ............................3.122
CARBURETED FUEL SYSTEM ............3.14
CARBURETOR ........................3.17
COLD START ENRICHMENT
(CHOKE OR FUEL PRIMER) .............3.33
DESCRIPTION & OPERATION............3.15
FUEL PUMP ..........................3.29
SPECIFICATIONS......................3.34
TROUBLESHOOTING...................3.16
CARBURETOR .........................3.17
2.5 HP MOTORS .......................3.18
4/56 HP MOTORS .....................3.19
9.9115 HP AND 25 HP V2 MOTORS........3.22
25/30 HP (3-CYL) MOTORS ..............3.25
CLOSED THROTTLE POSITION (CTP) SWITCH .3.133
REMOVAL& INSTALLATION ............3.133
TESTING ............................3.133
COLD START ENRICHMENT ..............3.33
CRANKSHAFT POSITION (CKP) SENSOR . . 3.124
REMOVAL& INSTALLATION ............3.125
TESTING ............................3.124
DIAGNOSTIC CHARTS ...................3.76
40-140 HP POWERHEADS ...............3.77
150-250 HP POWERHEADS ..............341
300 HP POWERHEADS .................3.85
DIAGNOSTIC TROUBLE CODES
40-140 HP EFI MOTORS ................3.42
1501175 HP EFI MOTORS ...............3.43
200-250 HP EFI MOTORS ...............3.44
300 HP EFI MOTORS ...................3.45
READING & CLEARING CODES ..........3.41
ECM PINOUTS & CIRCUIT OPERATING VALUES . 3.47
40150 HP MOTORS .....................3.47
60170 HP MOTORS .....................3.52
90-140 HP MOTORS ....................3.55
150-1 75 HP MOTORS ...................3.58
200-250 HP MOTORS ...................3.63
300 HP MOTORS ......................3.67
EFI SYSTEM RELAY ...................'3-137
ELECTRONIC FUEL INJECTION (EFI) ......3.35
AIR INTAKE SILENCER & FLAME ARRESTER .3-90
CKP SENSOR ........................3.124
CMP SENSOR ........................3.121
CTP SWITCH .........................3.133
DESCRIPTION & OPERATION............3.35
ECM................................3.127
EFI SYSTEM RELAY ...................3.137
ELECTRONIC THROTTLE VALVE ........3.135
ENGINE DIAGNOSTIC CHARTS ..........3.76
EVAPORATION PURGE VALVE ..........3.136
FUEL RAIL & INJECTORS ..............3.116
FUEL PRESSURE REGULATOR .........3.136
IAC VALVE ...........................3.138
LOW PRESSURE ELECTRIC FUEL PUMP .3-110
LOW PRESSURE MECHANICAL FUEL PUMP . .3.107
MAP SENSOR ........................3.131
MULTI-STAGE INDUCTION COMPONENTS 3-1 36
NEUTRAL (SAFETY) SWITCH ...........3.139
OIL CHANGE REMINDER SYSTEM........3.90
READING & CLEARING CODES ..........3.41
SELF DIAGNOSTIC SYSTEM .............3.41
SENSOR & CIRCUIT
RESISTANCEIOUTPUT TESTS ...........3.47
SHIFT POSITION SENSOR .............3.141
SPECIFICATIONS .....................3.142
TEMPERATURE SENSORS (CT. EM AND IAT) .3.128
THROTTLE BODY & INTAKE MANIFOLD ...3.94
THROTTLE POSITION SENSOR (TPS) ....3.133
TROUBLESHOOTING...................3.35
VST & HIGH PRESSURE FUEL PUMP ....3.111
VVT OIL CONTROL VALVE ..............3.142
ELECTRONIC THROTTLE VALVE .........3.135
OPERATIONAL CHECKS ...............3.135
REMOVAL& INSTALLATION ............3.135
ENGINE CONTROL MODULE (ECM) .......3.127
REMOVAL& INSTALLATION ............3.127
FLAME ARRESTER ......................3.90
REMOVAL & INSTALLATION .............3.90
FUEL ..................................3.2
OCTANE RATING .......................3-3
VAPOR PRESSURE .....................3.3
ALCOHOL-BLENDED FUELS ..............3.3
HIGH ALTITUDE OPERATION .............3.3
RECOMMENDATIONS ...................3.3
CHECKING FOR STALEICONTAMINATED FUEL .. 3.3
FUEL LINES & FITTINGS .................3.11
SERVICE .............................3.13
TESTING .............................3.11
FUEL PRESSURE REGULATOR ..........3.136
FUEL PUMP
ELECTRIC (HIGH) .....................3.111
ELECTRIC (LOW) .....................3.110
MECHANICAL........................3.107
FUEL RAIL & INJECTORS................3.116
EXPLODED VIEWS ....................3.120
REMOVAL & INSTALLATION ............3.118
TESTING ............................3.117
FUEL SYSTEM BASICS ...................3.2
SERVICE CAUTIONS ....................3.2
FUEL .................................3.2
FUEL SYSTEM PRESSURIZATION .........3.4
FUEL TANK .............................3.7
SERVICE ..............................3.8
FUEL TANK AND LINES ..................-3-7
FUEL LINES AND FITTINGS ..............3.11
FUEL TANK ............................3.7
IDLE AIR CONTROL (IAC) VALVE .........3.138
REMOVAL& INSTALLATION ............3.139
TESTING ............................3.138
INTAKE MANIFOLD (EFI) .................3.94
REMOVAL & INSTALLATION .............3.94
MANIFOLD ABSOLUTE PRESSURE
(MAP) SENSOR ........................3.131
REMOVAL& INSTALLATION ............3.132
TESTING ............................3.132
MULTI-STAGE INDUCTION COMPONENTS .3.136
NEUTRAL (SAFETY) SWITCH ............3.139
REMOVAL & INSTALLATION ............3.140
TESTING ............................3.139
OIL CHANGE REMINDER SYSTEM .........3.90
RESETTING ..........................3.90
PRESSURIZING THE FUEL SYSTEM ........3.7
RELIEVING PRESSURE (EFI) ..............3.5
40150 HP EFI MODELS ...................3.5
60170 HP EFI MODELS ...................3.5
9011151140 HP EFI MODELS ..............3.6
1501175 HP EFI MODELS .................3.6
200-300 HP EFI MODELS. ................3.6
SELF DIAGNOSTIC SYSTEM ..............3.41
DIAGNOSTIC TROUBLE CODES ..........3.42
READING & CLEARING CODES ..........3.41
SENSOR & CIRCUIT
RESISTANCEIOUTPUT TESTS ............3.47
ECM PINOUTS & CIRCUIT OPERATING VALUES .3-47
TESTING EFI COMPONENTS ............3.47
SHIFT POSITION SENSOR ..............3.141
SPECIFICATIONS
CARBURETOR ........................3.34
EFI .................................3.142
TEMPERATURE SENSORS (CT, EM AND IAT) ...3.128
REMOVAL& INSTALLATION ............3.130
TESTING ............................3.129
THROTTLE BODY .......................3.94
REMOVAL & INSTALLATION .............3.94
THROTTLE POSITION SENSOR (TPS) .....3.133
REMOVAL& INSTALLATION ............3.135
TESTING ............................3.134
VAPOR SEPARATOR TANK (VST) .........3.111
OVERHAUL ..........................3.115
REMOVAL& INSTALLATION ............3.113
TESTING ............................3.111
VVT OIL CONTROL VALVE ...............3.142
DESCRIPTION& OPERATION...........3.142
REMOVAL & INSTALLATION ............3.142
TESTING ............................3.142
If equipped, disconnect the negative battery cable ANYTIME work is
performed on the engine, especially when working on the fuel system.
This will help prevent the possibility of sparks during service (from
accidentally grounding a hot lead or powered component). Sparks
could ignite vapors or exposed fuel. Disconnecting the cable on
electric start motors will also help prevent the possibility fuel spillage if
an attempt is made to crank the engine while the fuel system is open.
Remember also that EFI motors don't even need to be cranked to spray
fuel from an open high-pressure fitting, as the fuel pump will run for a
few seconds anytime the key is turned to the ON position.
Fuel leaking from a loose, damaged, or incorrectly installed hose or
fitting may cause a fire or an explosion. ALWAYS pressurize the fuel
system and run the motor while inspecting for leaks after servicing any
component of the fuel system.
The carburetion or fuel injection, and the ignition principles of engine
operation must be understood in order to perform troubleshoot and repair an
outboard motors fuel system or to perform a proper tune-up on carbureted
motors.
if you have any doubts concerning your understanding of engine
operation, it would be best to study The Basic Operating Principles of an
engine as detailed under Troubleshooting in General information, Safety &
Tools section, before tackling any work on the fuel system.
The fuel systems used on engines covered by this manual include single
carburetors, multiple single barrel carburetors or electronic fuei injection. The
carbureted motors utilize various means of enriching fuel mixture for cold
starts, including a manual choke, electric choke, manual primer or electric
primer solenoid. Refer to the General Engine System Specifications chart in
the Maintenance & Tune-up section for more details as to what systems
were commonly used on what motors, but keep in mind that additional
systems were available as accessories for most motors (you could usually
add an electric primer or electric choke later if you desired or it could have
been added during rigging).
There is no way around it. Working with gasoline can provide for many
different safety hazards and requires that extra caution is used during all
steps of service. To protect yourself and others, you must take all necessary
precautions against igniting the fuel or vapors (which will cause a fire at best
or an explosion at worst).
Take extreme care when working with the fuel system. NEVER smoke
(it's bad for you anyhow, but smoking during fuel system service could
kill you much faster!) or allow flames or sparks in the work area.
Flames or sparks can ignite fuel, especially vapors, resulting in a fire at
best or an explosion at worst.
For starters, disconnect the negative battery cable EVERY time a fuei
system hose or fitting is going to be disconnected. It takes only one moment
of forgetfulness for someone to crank the motor, possibly causing a
dangerous spray of fuel from the opening. This is especially true on the high-
pressure fuel circuit of EFI motors, where just turning the key to on will
energize the fuel pump.
Gasoline contains harmful additives and is quickly absorbed by exposed
skin. As an additional precaution, always wear gloves and some form of eye
protection (regular glasses help, but only safety glasses can really protect
your eyes).
B Throughout service, pay attention to ensure that all components,
hoses and fittings are installed in the correct location and orientation
to prevent the possibility of leakage. Matchmark components before
they are removed as necessary.
Because of the dangerous conditions that result from working with
gasoiine and fuel vapors
always take extra care and be sure to follow these guidelines for safety:
Keep a Coast Guard-approved fire extinguisher handy when working.
Allow the engine to cool completely before opening a fuel fitting. Don't
all gasoline to drip on a hot engine.
The first thing you must do after removing the engine cover is to check
for the presence of gasoline fumes. If strong fumes are present, look for
leaking or damage hoses, fittings or other fuel system components and
repair.
Do not repair the motor or any fuel system component near any
sources of ignition, including sparks, open flames, or anyone smoking.
Clean up spilled gasoline right away using clean rags. Keep all fuel
soaked rags in a metal container until they can be properly disposed of or
cleaned. NEVER leave solvent, gasoline or oil soaked rags in the hull.
Don't use electric powered tools in the hull or near the boat during fuel
system service or after service, until the system is pressurized and checked
for leaks.
Fuel leaking from a loose, damaged or incorrectly installed hose or
fitting may cause a fire or an explosion. ALWAYS pressurize the fuel system
and run the motor while inspecting for leaks after servicing any component of
the fuel system.
@ See Figure 1
In some ways, fuel recommendations have become more complex as the
chemistry of modern gasoline changes. The major driving force behind the
many of the changes in gasoline chemistry was the search for additives to
replace lead as an octane booster and lubricant. These additives are
governed by the types of emissions they produce in the combustion process.
Also, the replacement additives do not always provide the same level of
combustion stability, making a fuel's octane rating less meaningful.
In the 1960's and 1970's, leaded fuel was common. The lead served two
functions. First, it served as an octane booster (combustion stabilizer) and
second, in 4-stroke engines, it served as a valve seat lubricant. Historically
for 2-stroke engines, the primary benefit of lead was to serve as a
combustion stabilizer. Lead served very well for this purpose, even in high
heat applications.
For decades now, all lead has been removed from the refining process.
This means that the benefit of lead as an octane booster has been
eliminated. Several substitute octane boosters have been introduced in the
place of lead. While many are adequate in an automobile engine. most do
not perform nearly as well as lead did, even though the octane rating of the
fuei is the same.
I I
OCTANE RATING
See Figure 1
A fuel's octane rating is a measurement of how stable the fuel is when
heat is introduced. Octane rating is a major consideration when deciding
whether a fuel is suitable for a particular application. For example, in an
engine, we want the fuel to ignite when the spark plug fires and not before,
even under high pressure and temperatures. Once the fuel is ignited, it must
burn slowly and smoothly, even though heat and pressure are building up
while the burn occurs. The unburned fuel should be ignited by the traveling
flame front, not by some other source of ignition, such as carbon deposits or
the heat from the expanding gasses. A fuel's octane rating is known as a
measurement of the fuel's anti-knock properties (ability for a controlled burn
without explosion from heat or compression). Essentially, the octane rating is
a measure of a fuel's stability.
Usually a fuel with a higher octane rating can be subjected to a more
severe combustion environment before spontaneous or abnormal
combustion occurs. To understand how two gasoline samples can be
different, even though they have the same octane rating, we need to know
how octane ratina is determined.
The ~merican~ociet~
of Testing and Materials (ASTM) has developed a
universal method of determinina the octane ratina of a fuel sample. The
octane rating you see on the pump at a gasoline-station is known as the
pump octane number. Look at the small print on the pump. The rating has a
formula. The rating is determined by the RtMi2 method. This number is the
average of the research octane reading and the motor octane rating.
The Research Octane Rating is a measure of a fuel's anti-knock
properties under a light load or part throttle conditions. During this test,
combustion heat is easily dissipated.
* The Motor Octane Rating is a measure of a fuel's anti-knock properties
under a heavy load or full throttle conditions, when heat buildup is at
maximum.
Suzuki recommends using a minimum octane rating of 87 AKO
(R+M)i2 or 91 RON for all of these motors. Although they recommend
avoiding fuels with ethanol or alcohol IF at all possible, Suzuki also
mentions that blends of unleaded gasoline and alcohol with equivalent
octane content may be used.
VAPOR PRESSURE
Fuel vapor pressure is a measure of how easily a fuel sample evaporates.
Many additives used in gasoline contain aromatics. Aromatics are light
hydrocarbons distilled off the top of a crude oil sample. They are effective at
increasing the research octane of a fuel sample but can cause vapor lock
(bubbles in the fuel line1 on a verv hot dav. If vou have an inconsistent
running engine and you suspect vapor lock, use a piece of clear fuel line to
look for bubbles, indicating that the fuel is vaporizing.
One negative side effect of aromatics is that they create additional
combustion products such as carbon and varnish. If your engine requires
high octane fuel to prevent detonation, de-carbon the engine more frequently
with an internal engine cleaner to prevent ring sticking due to excessive
varnish buildup.
ALCOHOL-BLENDED FUELS
Although Suzuki recommends avoiding fuels with ethanol or alcohol
IF at all possible, they also mention that blends of unleaded gasoline
and alcohol with equivalent octane content may be used.
When the Environmental Protection Agency mandated a phase-out of the
leaded fuels in January of 1986, fuel suppliers needed an additive to improve
the octane rating of their fuels. Although there are multiple methods currently
employed, the addition of alcohol to gasoline seems to be favored because
of its favorable results and low cost. Two types of alcohol are used in fuel
today as octane boosters, methanol (wood alcohol) or ethanol (grain
alcohol).
When used as a fuel additive, alcohol tends to raise the research octane
of the fuel, so these additives will have limited benefit in an outboard motor.
There are, however, some special considerations due to the effects of
alcohol in fuel.
Since alcohol contains oxygen, it replaces gasoline without oxygen
content and tends to cause the airlfuel mixture to become leaner.
* When alcohol blended fuels become contaminated with water, the
water combines with the alcohol then settles to the bottom of the tank. This
leaves the gasoline on a top layer.
OST Modern outboard fuel lines and plastic fuel system
components have been specially formulated to resist alcohol leaching
effects. However, the increase in ethanol use in the U.S. during
200512006 has shown there are still some concerns, especially with
boats that contain Fiberglass Reinforced Plastic (FRP) or Aluminum
gas tanks. For more details on these problems, please refer to the
Winterization procedures in the Maintenance and Tune-up section.
HIGH ALTITUDE OPERATION
At elevated altitudes there is less oxygen in the atmosphere than at sea
level. Less oxygen means lower combustion efficiency and less power
output. As a general rule, power output is reduced three percent for every
thousand feet above sea level.
On carbureted engines, re-jetting for high altitude does not restore lost
power, it simply corrects the air-fuel ratio for the reduced air density and
makes the most of the remaining available power. The most important thing
to remember when re-jetting for high altitude is to reverse the jetting when
return to sea level. If the jetting is left lean when you return to sea level
conditions, the correct airifuel ratio will not be achieved (the motor will run
very lean) and possible powerhead damage may occur.
RECOMMENDATIONS
According to the fuel recommendations that come with your outboard,
there is no engine in the product line that requires more than 87 octane
when rated by the RtMl2 or. Most Suzuki engines need only 87 octane. An
89 or higher octane rating generally means middle to premium grade
unleaded. Premium unleaded is more stable under severe conditions but
also produces more combustion products. Therefore, using premium
unleaded could lead to a need to perform de-carboning.
As stated earlier, Suzuki recommends avoiding fuels with alcohol (such as
ethanol) but realized this is not always possible.
H Check the emissions label found on your motor as it will normally
list the minimum required fuel octane rating for your specific model.
CHECKING FOR STALEICONTAMINATED FUEL
See Figures 2 thru 5
Outboard motors often sit weeks at a time making them the perfect
candidate for fuel problems. Gasoline has a short life, as combustibles begin
evaporating almost immediately. Even when stored properly, fuel starts to
deteriorate within a few months, leavina behind a stale fuel mixture that can
cause hard-starting, poor engine performance and even lead to possible
engine damage.
Further more, as gasoline evaporates it leaves behind gum deposits that
can clog filters, lines and small passages. Although the sealed high-pressure
fuel system of an EFI motor is MUCH less susceptible to fuel evaporation,
the low-pressure fuel systems of all engines can suffer the affects.
Carburetors, due to their tiny passages and naturally vented designs are the
most susceptible components on non-EFI motors.
As mentioned under Alcohol-Blended fuels, modern fuels very often
contain alcohol, which is hygroscopic (meaning it absorbs water). And, over
time, fuel stored in a partially filled tank or a tank that is vented to the
atmosphere will absorb water. In the past, water would settle to the bottom of
the tank, promoting rust (in metal tanks) and leaving a non-combustible
mixture at the bottom of a tank that could leave a boater stranded. But with
alcohol-blended fuels the water can actually bond with the alcohol and
remain in suspension in the fuel so that in sufficient quantity it can drastically
reduce the combustibility of the fuel itself.
One of the first steps to fuel system troubleshooting is to make sure the
fuel source is not at fault for engine performance problems. Check the fuel if
the engine will not start and there is no ignition problem. Stale or
contaminated fuels will often exhibit an unusual or even unpleasant unusual
odor.
Fig. 4 . . .just make sure it's a screw and not
Fig. 2 Carburetor float bowls are normally a jet needle (by trying to very gently turn it
equipped with a drain screw on the lower Fig, 3 To drain the carburetor, remove the inward, noting the position if it does move
side of the carb drain screw. . . before you try and unthread it)
Fig. 5 Commercial additives, such as Sta-bil, may be used to help
prevent "souring"
The best method of disposing stale fuel is through a local waste
pickup service, automotive repair facility or marine dealership. But, this
can be a hassle. If fuel is not too stale or too badly contaminated, it
may be mixed with greater amounts of fresh fuel and used to power
lawnlyard equipment or even an automobile (if greatly diluted so as to
prevent misfiring, unstable idle or damage to the automotive engine).
But we feel that it is much less of a risk to have a lawn mower stop
running because of the fuel problem than it is to have your boat motor
quit or refuse to start.
Carburetors are normally equipped with a float bowl drain screw that can
be used to drain fuel from the carburetor for storage or for inspection. For
EFI models, a fuel system drain is normally found on the vapor separator
tank, but access to the drain may require removal of the intake manifold or
other interfering components (depending upon the model).
For some motors, it may be easier to drain a fuel sample from the hoses
leading to or from the low pressure fuel filter or fuel pump. Removal and
installation instructions for the fuel fillers are provided in the Maintenance
Section, while fuel pump procedures are found in this section. To check for
stale or contaminated fuel:
1. Disconnect the negative battery cable for safety. Secure it and place
tape or a small plastic bag over the end so that it cannot accidentally contact
the terminal and complete the circuit.
Throughout this procedure, clean up any spilled fuel to prevent a fire
hazard.
2. For carbureted motors, remove the float bowl drain screw, then allow
a small amount of fuel to drain into a glass container.
If there is no fuel present in the carburetor, disconnect the inlet line
from the fuel pump and use the fuel primer bulb to obtain a sample as
on EFI motors.
3. For EFI motors, disconnect the fuel supply hose from the pump or
low pressure fuel filter (as desired), then squeeze the fuel primer bulb to
obtain a small sample of fuel. Place the sample in a clear glass container
and reconnect the hose.
If a sample cannot be obtained from the fuel filter or pump supply
hose, there is a problem with the fuel tank-to-motor fuel circuit. Check
the tank, primer bulb, fuel hose, fuel pump, fitting or inlet needle on
carbureted models.
4. Check the appearance and odor of the fuel. An unusual smell, signs
of visible debris or a cloudy appearance (or even the obvious presence of
water) points to a fuel that should be replaced.
5. If contaminated fuel is found, drain the fuel system and dispose of
the fuel in a responsible manner, then clean the entire fuel system. On EFI
models, this includes draining the vapor separator tank, then properly
draining the high-pressure fuel system by relieving system pressure
according to the instructions in this section.
If debris is found in the fuel system, clean and/or replace all fuel
filters.
6. When finished, reconnect the negative battery cable, then properly
pressurize the fuel system and check for leaks.
When it comes to safety and outboards, the condition of the fuel system is
of the utmost importance. The system must be checked for signs of damage
or leakage with every use and checked, especially carefully when portions of
the system have been opened for service.
The best method to check the fuel system is to visually inspect the lines,
hoses and fittings once the system has been properly pressurized.
Furthermore, EFI motors are equipped with two inter-related fuel circuits,
a low pressure circuit that is similar to the circuit that feeds carburetors on
other motors and a high pressure circuit that controls pressure in the sealed
high pressure portion of the system (the fuel lines that feed the injectors). As
its name implies, the high pressure circuit contains fuel under pressure that,
if given the chance, will spray from a damaged/loose hose or fitting. When
servicing components of the high pressure system, the fuel pressure must
first be relieved in a safe and controlled manner to help avoid the potential
explosive and dangerous conditions that would result from simply opening a
fitting and allowing fuel to spray uncontrolled into the work area.
1
Fia. 6 To relieve fuel svstem pressure on
40750 hp motors, first locate the intake
manifold and VST assembly. . .
RELIEVING FUEL SYSTEM PRESSURE (EFI MOTORS ONLY)
DERATE
Before servicing the high pressure fuel circuit or related components,
including the vapor separator tank, high pressure filter, fuel rail, injector and
related lines, the pressure must be released. Failure to do so in a proper
manner could lead to high pressure fuel spray, excessive concentrations of
vapors and an extremely dangerous, potentially explosive condition.
40150 Hp EFI Models
+ See Figures 6,7 and 8
1. Turn the key switch to OFF.
2. On the rear port side of the motor locate and disconnect the high
pressure fuel pump wiring from the top of the Vapor Separator Tank (VST,
just above the intake manifold and just a bit in front of the high-pressure
filter) by releasing the connector's lock tab, then pulling the connector free,
3. Tag, then disconnect the wiring (primary lead connectors) from each
ignition coil at the rear of the motor.
4. Use the key switch to crank the engine in 3 second bursts for 5-10
times. This will dissipate the fuel pressure in the lines. After the first couple of
bursts, start squeezing the high pressure line (coming out of the rear of the
high pressure filter, just behind the fuel pump connector, on top of the
powerhead) to determine when the pressure is released. Once the hose is
soft to the touch, crank the engine a few more times to ensure pressure is
gone.
B Even after most or all of the pressure has been dissipated, there
may still be some liquid fuel left in the lines. Always wrap a shop rag
around fittings before they are disconnected to catch any escaping
fuel.
5. Unless necessary for service procedures or for safety, reconnect the
ignition coil primary leads.
6. Disconnect the negative battery cable for safety during service.
andlor leave the fuel pump wiring disconnected until the maintenance or
repairs have been completed.
We still recommend disconnecting the negative battery cable,
especially if any work will be one or around electrical components. Any
work on or near the gearcase, propeller or other potentially hazardous
moving parts is also good reason to keep the battery disconnected.
7. After maintenance or repairs are finished, fully pressurize the high
and low pressure fuel circuits and thoroughly check the system for leakage.
60R0 Hp EFI Models
+ See Figure 9
1. Turn the key switch to OFF.
2. Disconnect the negative battery cable for safety during service and
leave it disconnected until the maintenance or repairs have been completed.
3. Locate the high pressure fuel rail (fuel delivery pipe) on the rear port
side of the cylinder head. At the top of the fuel rail is a pipe plug, cover the
pipe plug with a shop rag and then slowly and carefully loosen it 2-3 turns to
Fig. 8 .. .then disconnect the primary leads
from the ignition coils and crank the motor
gradually allow fuel pressure in the line to bleed off (spray into the rag). Wipe
up right away any fuel which is not caught by the rag.
When releasing fuel pressure using the screw on the top of the fuel rail,
use extreme caution to prevent fuel from spraying uncontrolled into the
work area. There must be NO open flames, sparks or other sources of
ignition. It is imperative that there is proper ventilation in order to
dissipate vapors. Wear safety glasses to protect your eyes, gloves to
protect your skin and, finally, keep extra rags handy, as one might not
do the trick.
4. Check that fuel pressure has been released by pinching the high
pressure fuel hose that comes out of the bottom of the rail to feel that is has
softened. Back the plug out further to confirm, then tighten the plug to 29 ft.
Ibs. (40 Nm).
Even after most or all of the pressure has been dissipated, there
may still be some liquid fuel left in the lines. Always wrap a shop rag
around fittings before they are disconnected to catch any escaping
fuel.
We still recommend disconnecting the negative battery cable,
especially if any work will be one or around electrical components. Any
work on or near the gearcase, propeller or other potentially hazardous
moving parts is also good reason to keep the battery disconnected.
5. After maintenance or repairs are finished, fully pressurize the high
and low pressure fuel circuits and thoroughly check the system for leakage.
,
Fig. 9 Fuel rail and pipe plug -60170 hp motors
90/115/140 Hp EFI Models
See Figures 10 thru 13
1. Turn the key switch to OFF.
2. Locate the high pressure fuel pump which is mounted in the top of
the Vapor Separator Tank (VST) assembly at the rear starboard side of the
powerhead, between the powerhead itself and the intake manifold.
Disconnect the wiring from the pump (you should be able to access it
between the top two runners of the intake manifold) by releasing the
connector's lock tab, then pulling the connector free.
3. Tag, then disconnect the wiring (primary lead wire connector) from
the top of each ignition coil.
4 Use the key switch to cram the engine in 3 second bursts for 5-10
times. This will dissipate the fuel pressure in the lines. After the first couple of
bursts, start squeezing the high pressure line (attached to the top of the'fuel
rail) in order to determine when the pressure is released. Once the hose is
soft to the touch, crank the engine a few more times to ensure pressure is
gone.
H Even after most or all of the pressure has been dissipated, there
may still be some liquid fuel left in the lines. Always wrap a shop rag
around fittings before they are disconnected to catch any escaping
fuel.
5. Unless necessary for service procedures or for safety, reconnect the
ignition coil primary leads.
6. Disconnect the negative battery cable for safety during service,
andlor leave the fuel pump wirina disconnected until the maintenance or
repairs have been completed. -
Fig. 10 To relieve fuel system pressure on 90-140 hp motors, start
by locating the VST assembly behind the intake manifold. ..
We still recommend disconnecting the negative battery cable,
especially if any work will be one or around electrical components. Any
work on or near the gearcase, propeller or other potentially hazardous
moving parts is also good reason to keep the battery disconnected.
7. After maintenance or repairs are finished, fully pressurize the high
and low pressure fuel circuits and thoroughly check the system for leakage.
1501175 Hp EFI Models
1. Turn the key switch to OFF.
2. On the side of the motor, just above the intake manifold, locate the
fuel hose guard. Remove the 3 bolts (one at either end and one toward the
top, center, at the engine lifting bracket) and remove the hose guard for
access.
3. Now at the end of the intake manifold locate the Vapor Separator
Tank (VST) assembly and find the high pressure fuel pump connector at
about the top center of the assembly. Unplug the wiring for the high pressure
fuel pump.
4. Lastly, go the center of the valve cover. then tag and disconnect the
primary wiring from each of the ignition coils to disable the ignition system.
5. Use the key switch to crank the engine in 3 second bursts for 5-10
times. This will dissipate the fuel pressure in the lines. After the first couple of
bursts, start squeezing the high pressure line (which runs across the top of
the intake manifold and enters the top of the fuel rail) in order to determine
when the pressure is released. Once the hose is soft to the touch, crank the
engine a few more times to ensure pressure is gone.
H Even after most or all of the pressure has been dissipated, there
may still be some liquid fuel left in the lines. Always wrap a shop rag
around fittings before they are disconnected to catch any escaping
fuel.
6. Unless necessary for service procedures crf~ safety, reconnect the
ignition coil primary leads.
7. Disconnect the negative battery cable for safety during service,
and/or leave the fuel pump wiring disconnected until the maintenance or
repairs have been completed.
We still recommend disconnecting the negative battery cable,
especially if any work will be one or around electrical components. Any
work on or near the gearcase, propeller or other potentially hazardous
moving parts is also good reason to keep the battery disconnected.
8. After maintenance or repairs are finished, fully pressurize the high
and low pressure fuel circuits and thoroughly check the system for leakage,
then install the fuel hose guard and tighten the bolts securely.
200-300 Hp EFI Models
1. Turn the key switch to OFF.
2. Locate the fuel Vapor Separator Tank (VST) assembly on the
powerhead (for more details about the VST, refer to the Vapor Separator
Tank information found later in this section). Disconnect the high pressure
fuel pump wiring from the top of the vapor separator.
3. On 300 hp models, remove the bolts from the starboard and port air
duct guard assembly, then remove the assembly for access to the ignition
coils.
Fig. 13 . ..pressure is relieved when the
Fig. 11 . ,.and unplug the wiring for the Fig. 12 Next, unplug the primary leads from high pressure fuel line to the top of the fuel
high pressure fuel pump the ignition coils and crank the motor. . . rail has softened
4. Tag, then disconnect the wiring (primary lead wire connector) from
each ignition coil on the valve covers in order to disable the ignition system.
5. With both the fuel pump and ignition systems now disabled, use the
key switch to crank the engine in 3 second bursts for 5-10 times. This will
dissipate the fuel pressure in the lines. After the first couple of bursts, start
squeezing the high pressure line (running into the high pressure fuel filter on
top of the powerhead) to determine when the pressure is released. Once the
hose is soft to the touch, crank the engine a few more times to ensure
pressure is gone.
Even after most or all of the pressure has been dissipated, there
may still be some liquid fuel left in the lines. Always wrap a shop rag
around fittings before they are disconnected to catch any escaping
fuel.
6. Unless necessary for service procedures or for safety, reconnect the
ignition coil primary leads.
7. Disconnect the negative battery cable for safety during service,
and/or leave the fuel pump wiring disconnected until the maintenance or
repairs have been completed.
H We still recommend disconnecting the negative battery cable,
especially if any work will be one or around electrical components. Any
work on or near the gearcase, propeller or other potentially hazardous
moving parts is also good reason to keep the battery disconnected.
8. After maintenance or repairs are finished, fully pressurize the high
and low pressure fuel circuits and thoroughly check the system for leakage.
For 300 hp motors, don't forget to reinstall the starboard and port air duct
guard assembly.
PRESSURIZING THE FUEL SYSTEM (CHECKING FOR LEAKS)
Fuel leaking from a loose, damaged or incorrectly installed hose or
fitting may cause a fire or an explosion. ALWAYS pressurize the fuel
system and run the motor while inspecting for leaks after servicing any
component of the fuel system.
Carbureted Models
Carbureted engines covered by this manual are only equipped with a low
pressure fuel system, making pressure release before service a non-issue.
But, even a low pressure fuel system should be checked following repairs to
make sure that no leaks are present. Only by checking a fuel system under
normal operating pressures can you be sure of the system's integrity.
If equipped, disconnect the negative battery cable ANYTIME work is
performed on the engine, especially when working on the fuel system.
This will help prevent the possibility of sparks during service (from
accidentally grounding a hot lead or powered component). Sparks
could ignite vapors or exposed fuel. Disconnecting the cable on
electric start motors will also help prevent the possibility fuel spillage if
an attempt is made to crank the engine while the fuel system is open.
And on EFI motors, it prevents the electric fuel pump from running
should the key be turned to on (even without cranking) which would
cause high pressure fuel spray if a fuel component of the EFI system is
disconnected.
Fuel leaking from a loose, damaged or incorrectly installed hose or
fitting may cause a fire or an explosion. ALWAYS pressurize the fuel
system and run the motor while inspecting for leaks after servicing any
component of the fuel system.
Most carbureted engines (except some integral tank models with gravity
feed) utilize a fuel primer bulb mounted inline between the fuel tank and
engine. On models so equipped, the bulb can be used to pressurize that
portion of the fuel system. Squeeze the bulb until it and the fuel lines feel
firm with gasoline. At this point check all fittings between the tank and motor
for signs of leakage and correct, as necessary.
Once fuel reaches the engine it is the job of the fuel pump($ to distribute
it to the carburetor(s). The fuel is pumped directly from the pump to the
carburetor
No matter what system you are inspecting, start and run the motor with
the engine top case removed, then check each of the system hoses, fittings
and gasket-sealed components to be sure there is no leakage after service.
EFI Models
EFI models covered by this manual utilize 2 fuel circuits. A low pressure
circuit consisting of a fuel tank, primer bulb, low pressure fuel pump and low
pressure filter and fuel line to the vapor separator tank all operate in the
same manner as the low pressure fuel system of a carbureted motor. The
high pressure circuit consists of the electric fuel pump (integral with the
vapor separator tank), the high pressure filter, the fuel raillinjectors and the
high pressure lines.
Although it is necessary to pressurize and inspect both systems after
repairs have been performed on the motor, it is especially important to
properly check the high pressure circuit. Leaks from the high pressure circuit
(as you might well expect) will be under much greater pressures leading to
even more potentially hazardous conditions than a low pressure leak. That's
not to say a low pressure leak isn't dangerous, but a high pressure leak can
be even more so.
After ANY repair to the fuel system, ALWAYS pressurize and check the
low pressure circuit as follows:
1. Make sure the fuel tank is sufficiently full to provide an uninterrupted
fuel source, then squeeze the bulb until it begins to feel firm. Check the low
pressure lines, fittings and components for signs of leakage before
continuing.
2. Pressurize the high pressure fuel circuit as follows: Make sure the
negative battery cable is connected (if removed for service), then turn the
key switch to ON for 3 seconds (6 seconds for 150-300 hp motors, as the
pump either runs longer or the module requires a little more time to
actuatelreset the circuit) and then OFF again for at least 3 seconds. Repeat
the key switch cycle 3-4 times, while listening at the vapor separator to hear
the high pressure pump run each time the key is turned to the ON position. If
the pump does not run, check the fuel pump and circuit as described in this
section under Vapor Separator Tank and High Pressure Pump in this section.
Once pressurized, check the high pressure lines, fittings and components for
signs of leakage.
3. Start the engine, then allow it to idle it for a few seconds, while
continuing to scan all fuel system components for signs of leakage.
4 Stop the motor and recheck the fittings.
5. Repair any leakage, then recheck the fuel system integrity.
If a problem is suspected in the fuel supply, tank and/or lines, by far the
easiest test to eliminate these components as possible culprits is to
substitute a known good fuel supply. This is known as running a motor on a
test tank (as opposed to running a motor IN a test tank, which is an entirely
different concept). If possible, borrow a portable tank, fill it with fresh
gasoline and connect it to the motor.
B When using a test fuel tank, make sure the inside diameter of the
fuel hose and fuel fittings is of sufficient size (meaning it is at least of
the same size with which the motor was originally rigged. In general
that means at least 5/16 in./8mm for small and midrange motors or
about 318 in.19.5mm for larger motors).
In addition, make sure the pickup tubelfilter is not too restrictive, and for
proper lift pump operation make sure the pump is not located too far away or
above the bottom of the tank.
See Figures 14 and 15
There are 3 different categories of fuel tanks that might be used along
with these Suzuki motors. Only the very smallest Suzuki motors (2.5-6 hp)
are equipped with an integral fuel tank mounted to the powerhead. But, most
Fig. 14 Although most of these motors are
not rigged with portable tanks, almost any Fig. 15 Remote tanks are connected to the Fig. 16 Fuel tank and fuel valve for 2.5 hp
of them CAN be motor using a fuel tine with a primer bulb motors
I I
motors (from 4 hp and larger) may be rigged using either a portable fuel tank
or a boat mounted tank (though honestly by the time you get to the 150t hp
range, you almost ALWAYS see them rigged with a boat mounted tank). In
either case (portable or boat mounted), a tank that is not mounted to the
engine itself is commonly called a remote tank.
Although many Suzuki dealers rig boats using Suzuki fuel tanks,
there are many other tank manufacturers and tank designs may vary
greatly. Your outboard might be equipped with a tank from the engine
manufacturer, the boat manufacturer or even another tank
manufacturer. Although components used, as well as the techniques
for cleaning and repairing tanks are similar for almost all fuel tanks be
sure to use caution and common sense. If the design varies from the
instructions or illustrations included here, you'll have to use common
sense.
If we reference 2 or 4 screws for something and the component is still
tight after removing that many, look for another or for another means of
securing the component, don't force it. Refer to a reputable marine repair
shop or marine dealership when parts are needed for aftermarket fuel tanks.
Whether or not your boat is equipped with a boat mounted, built-in tank
depends mostly on the boat builder and partially on the initial engine installer.
Boat mounted tanks can be hard to access (sometimes even a little hard to
find if parts of the deck must be removed. When dealing with boat mounted
tanks, look for access panels (as most manufacturers are smart or kind
enough to install them for tough to reach tanks). At the very least, all
manufacturers must provide access to fuel line fittings and, usually, the fuel
level sender assembly.
No matter what type of tank is used, all must be equipped with a vent
(either a manual vent or an automatic one-way check valve) which allows air
in (but should prevent vapors from escaping). An inoperable vent (one that is
blocked in some fashion) would allow the formation of a vacuum that could
prevent the fuel pump from drawing fuel from the tank. A blocked vent could
cause fuel starvation problems. Whenever filling the tank, check to make
sure air does not rush into the tank each time the cap is loosened (which
could be an early warning sign of a blocked vent).
If fuel delivery problems are encountered, first try running the motor with
the fuel tank cap removed to ensure that no vacuum lock will occur in the
tank or lines due to vent problems. If the motor runs properly with the cap
removed but stall, hesitates or misses with the cap installed, you know the
problem is with the tank vent system.
SERVICE
DERATE
Integral Fuel Tanks
See Figures 16 thru 21
v
Generally only the smallest of the Suzuki portable outboards (2.5 hp and
the 41516 hp motors) may be equipped with an integral fuel tank. On these
powerheads the tank is installed at the front of the motor (right in front of the
flywheel and powerhead). Unlike some manufacturers that tend to use a filter
and fuel petcock (fuel valve) mounted in the bottom of the tank, Suzuki tends
to use an inline filter and inline valve which can be more easily accessed and
serviced should tne filter, a line, or a valve become plugged.
Tank Cap Assy (1)
Clip (6) for DF4
Clip (9) for DF5
1 -Clip (1) 10 -Hose (1)
2 -Hose (1) 11 -Protector (2)
3 -Clip (6) for DF4 12 -Screw (2)
Clip (9) for DF5 13 -Fuel Cock Assy (1)
4 -3-way Joint (1) 14 -Gasket (1)
5 -Hose (1) 15 -O-ring (1)
6 -Hose (1) 16 -Cock Cap (1)
7 -Washer (2)
8 -Cushion (2)
9 -Bolt (2)
Fig. 17 Exploded view of the fuel tank on 41516 hp motors
Fig. 19 . . .and the fuel line is (or lines are)
Fig. 18 To remove the tank, make sure the disconnected (either here at the valve or at Fig. 20 On 41516 hp motors the fuel valve is
retaining bolts are removed. . . the pump as applicable) retained by 2 screws below the engine cover
To check fuel flow, disconnect the fuel line at the carburetor (2.5 hp
motors) or the fuel pump (41516 hp motors) and fuel should flow from the line
if the shut-off valve is open. If fuel is not present, the usual cause is a
plugged inline filter. Would you believe, many times a lack of fuel at the
carburetor is caused because the vent on the fuel tank was not opened or
has become clogged, creating a vacuum strong enough to prevent fuel from
flowing? As mentioned under Fuel Tank in this section, it is important to
make sure the vent is open or clear at all times during engine operation to
prevent formation of a vacuum in the tank that could prevent fuel from
reaching the fuel pump or carburetor.
To remove the tank, proceed as follows:
1. Make sure the fuel tank valve is shut off.
2. For access, remove the Manual Starter assembly, as detailed in the
Hand Rewind Starter section.
Have a shop rag handy to catch any fuel that was left in the tank or
line when it is disconnected.
3. On 2.5 hp motors proceed as follows:
a. Disconnect the fuel output hose from the fuel valve, then remove the
fuel tank and fuel valve as an assembly.
b. If necessary, loosen the screw securing the valve to the tank, then
separate the two for access to the inline filter. If the filter is clogged or
damaged, replace the element. If damage is found to the fuel valve itself the
assembly should be replaced.
4. On 2.5 hp motors proceed as follows:
a. Remove the 2 bolts still securing the fuel tank.
There are some discrepancies between Suzuki technical literature
and our test motors. Specifically, some of the literature shows the fuel
tank output line on these motors as connecting directly to the fuel
valve, and though that MIGHT be true on some, on some of our test
motors it was not. On some of our motors the tank output line
connected to the input port of the fuel pump, then the fuel pump output
line connected to the fuel valve input line. Lastly the fuel valve output
line connected to the carburetor.
b. Tag and disconnect the fuel tank output fuel line at the fuel valve or
pump (as applicable). If there is fuel still in the tank, immediately PLUG or
pinch the fuel tank hose to minimize fuel spillage.
c. Remove the tank completely from the motor.
d. If you are removing the valve also, if not done already, tag and
disconnect the fuel lines from the valve. Remove the two bolts from the
underside of the engine cover, then remove the valve.
5. Check the tank, filler cap and gasket for wear or damage. Make sure
the vent on the tank cap is operational and not clogged. Same goes for the
fuel valve, make sure it is operational, not clogged and does not leak.
Replace any components as necessary to correct any leakage (if found).
6. If cleaning is necessary, flush the tank with a small amount of solvent
or gasoline, then drain and dispose of the flammable liquid properly.
7. When installing the tank, be sure all fuel lines are connected properly
and that the retaining screws are securely bolted in place.
8. Refill the tank and pressure test the system by opening the fuel
valve, then starting and running the engine.
Fig. 21 We realize the Suzuki diagrams make it look like the tank
connects directly to the fuel valve, but it obviously varies, as this
test motor shows the fuel line running from the tank to the fuel
pump, and then the pump output line goes to the fuel valve
Portable Fuel Tanks
See Figures 15 and 22 thru 25
Modern fuel tanks are vented to prevent vapor-lock of the fuel supply
system, but are normally vented by a one-way valve to prevent pollution
through the evaporation of vapors. A squeeze bulb is used to prime the
system until the powerhead is operating. Once the engine starts, the fuel
pump, mounted on the powerhead pull fuel from the tank and feeds the
carburetor(s) or EFI high pressure fuel circuit, as applicable. The pickup unit
in the tank is often sold as a complete unit, but without the gauge and float
(when attached, as on the steel Suzuki tanks).
To disassemble and inspect or replace tank components, proceed as
follows:
1. For safety, remove the filler cap and drain the tank into a suitable
container.
2. Disconnect the fuel supply line from the tank fitting.
3. To replacelservice thepickup unit on plastic ~uzuki plastic tanks
there is normally a threaded fitting to which the pickup tube and filter element
attaches.
4. To replacelservice the pickup unit and float assembly on steel Suzuki
tanks, first remove the screws (normally 4) securing the unit in the tank.
Next, lift the pickup unit up out of the tank. Remove the Phillips screws
(usually 2) securing the fuel gauge to the bottom of the pickup unit and set
the gauge aside for installation onto the new pickup unit.
B if the pickup unit is not being replaced, clean and check the screen
for damage. It is possible to bend a new piece of screen material
around the pickup and solder it in place without purchasing a complete
new unit.
5. If equipped with a level gauge assembly, check for smooth, non-
binding movement of the float arm and replace iibinding is found. Check the
float itself for physical damage or saturation and replace, if found.
6. Check the fuel tank for dirt or moisture contamination. If any is found
use a small amount of gasoline or solvent to clean the tank. Pour the solvent
in and slosh it around ti loosen and wash away deposits, then pour out the
solvent and recheck. Allow the tank to air drv, or heto it alona with the use of
an air hose from a compressor.
Fig. 22 Always make a tank vent is open or operable
~onnector
1
Tank Cap (1) Plug (1) &----Filter (1)
Gasket (1) -43 0-Ring (1)
,
Fuel Tank (1)
(1) Fuel hose asw (1) [@primer bulb (I)]
[@Connector] [@Connector (I)]
[@Clip (411
Fig. 23 Exploded view of a typical small plastic Suzuki portable fuel
tank
Use extreme care when working with solvents or fuel. Remember that
both are even more dangerous when their vapors are concentrated in a
small area. No source of ignition from flames to sparks can be allowed
in the workplace for even an instant.
To install:
7. On steel Suzuki tanks, attach the fuel gauge to the new pickup unit
and secure it in place with the Phillips screws. Clean the old gasket material
from fuel tank and, if being used, the old pickup unit. Position a new
gasketheal, then work the float arm down through the fuel tank opening, and
at the same time the fuel pickup tube into the tank. It will probably be
necessary to exert a little force on the float arm in order to feed it all into the
hole. The fuel pickup arm should spring into place once it is through the hole.
Secure the pickup and float unit in place with the attaching screws.
8. On plastic Suzuki tanks, make sure the filter is secure on the bottom
of the pickup tube, then make sure the tube is secure on the fitting. Check
the tank threads to make sure they are clean and undamaged. Install the
assembly using a new O-ring and tighten securely, but do not over-tighten
and damage the tank.
9. Connect the line to the fuel tank, then pressurize the fuel system and
check for leaks.
Boat Mounted Fuel Tanks
See Figures 15 and 26
The other type of remote fuel tank sometimes used on these models
(usually only on the largest models covered by this manual but could include
midrange motors too) is a boat mounted built-in tank. Depending on the boat
manufacturer, built-in tanks may vary greatly in actual shapeldesign and
access. All should be of a one-wav vented to orevent a vacuum lock. but
capped to prevent evaporation design.
Most boat manufacturers are kind enough to incorporate some means of
access to the tank should fuel lines, fuel pickup or floats require servicing.
I /
connector
-Gasket (1
Fuel
Tank (1)
1 -Clip (4)
2 -Primer Bulb (1)
Fig. 24 Alternate plastic Suzuki tank (with float level filler cap)
1 -Connector (1) 8 -Lens (1)
3 -Clip (4) 9 -Gasket (1)
4 -Primer bulb (1) 10-Screw 12}
5 -Conector (1) 11-Float (1)'
6 -Cover (1) 12-Push Nut (1)
7 -Gasket (1) 13-Gasket (1)
1 Fia. 25 Exoloded view of a tvoical steel Suzuki oortable fuel tank 1
Fig. 26 Most of the mid-range and larger motors will probably use
boat mounted tanks
But, the means of access will vary greatly from boat-to-boat. Some might
contain simple access panels, while others might require the removal of one
or more minor or even major components for access. If you encounter
difficulty, seek the advice of a local dealer for that boat builder. The dealer or
hislher techs should be able to set you in the right direction.
Observe all fuel system cautions, especially when working in recessed
portions of a hull. Fuel vapors tend to gather in enclosed areas causing
an even more dangerous possibility of explosion.
+ See Figure 15
In order for an engine to run properly it must receive an uninterrupted and
unrestricted flow of fuel. This cannot occur if improper fuel lines are used or
if any of the lineslfittings are damaged. Too small a fuel line could cause
hesitation or missing at higher engine rpm. Worn or damaged lines or fittings
could cause similar problems (also including stalling, poorlrough idle) as air
might be drawn into the system instead of fuel. Similarly, a clogged fuel line,
fuel filter or dirty fuel pickup or vacuum lock (from a clogged tank vent as
mentioned under Fuel Tank) could cause these symptoms by starving the
motor for fuel.
If fuel delivery problems are suspected, check the tank first to make
sure it is properly vented, then turn your attention to the fuel lines. First
check the lines and valves for obvious signs of leakage, then check for
collapsed hoses that could cause restrictions.
B If there is a restriction between the primer bulb and the fuel tank,
vacuum from the fuel pump may cause the primer bulb to collapse.
Watch for this sign when troubleshooting fuel delivery problems.
Only use the proper fuel lines containing suitable Coast Guard ratings
on a boat. Failure to do so may cause an extremely dangerous
condition should fuel lines fail during adverse operating conditions.
TESTING
Fuel Line Quick Check
+ See Figure 15
Stalling, hesitation, rough idle, misses at high rpm are all possible results
of problems with the fuel lines. A quick visual check of the lines for leaks,
kinked or collapsed lengths or other obvious damage may uncover the
problem. If no obvious cause is found, the problem may be due to a
restriction in the line or a problem with the fuel pump.
If a fuel delivery problem due to a restriction or lack of proper fuel
flow is suspected, operate the engine while attempting to duplicate the
miss or hesitation. While the condition is present, squeeze the primer bulb
rapidly to manually pump fuel from the tank to (and through) the fuel pump to
the carburetors (or EFI vapor separator tank, as applicable). If the engine
then runs properly while under these conditions, suspect a problem with a
clogged restricted fuel line, a clogged fuel filter or a problem with the fuel
Pump.
Checking Fuel Flow at Motor
See Figures 15 and 27 thru 30
To perform a more thorough check of the fuel lines and isolate or
eliminate the possibility of a restriction, proceed as follows:
1. For safety, disconnect the spark plug lead(s), then ground each lead
to the powerhead to prevent sparks and to protect the ignition system. On Dl
ignitions you can disconnect the primary leads to the coils and leave the
coils in place.
2. Disconnect the fuel line from the engine. Place a suitable container
over the end of the fuel line to catch the fuel discharged. If equipped with a
quick-connect fitting, insert a small screwdriver into the end of the line to
hold the valve open.
Fig. 27 Remove the fuel supply line fitting
from the engine to check fuel flow (quick- Fig. 28 Typical fuel quick-connector with 0-Fig. 29 Another method is to remove the
ring and check valve visible fuel line at the fuel pump and check for flow
1 Fig. 30 Compressed air can be used to check for obstructions
3. Squeeze the primer bulb and observe if there is satisfactory fuel flow
from the line. If there is no fuel discharged from the line, the check valve in
the squeeze bulb may be defective, or there may be a break or obstruction in
the fuel line.
4. If there is a good fuel flow, reconnect the tank-to-motor fuel supply
line and disconnect the fuel line from the carburetorfs) or EFI vapor
separator (basically the other end of the fuel pump output line), directing that
line into a suitable container. Crank the powerhead. If the fuel pumD is
operating properly, a healthy stream of fuel should pulse out of theline. If
sufficient fuel does not pulse from the line, compare flow at either side of the
inline fuel filter (if equipped) or check the fuel pump.
5. Continue cranking the powerhead and catching the fuel for about 15
pulses to determine if the amount of fuel decreases with each pulse or
maintains a constant amount. A decrease in the discharge indicates a
restriction in the line. If the fuel line is plugged, the fuel stream may stop. If
there is fuel in the fuel tank but no fuel flows out the fuel line while the
powerhead is being cranked, the problem may be in one of several areas:
Plugged fuel line from the fuel pump to the carburetor(s) or vapor
separator tank (EFI).
Defective O-ring in fuel line connector into the fuel tank.
Defective O-ring in fuel line connector into the engine.
Defective fuel pump.
The line from the fuel tank to the fuel pump may be plugged; the line
may be leaking air; or the squeeze bulb may be defective.
* Defective fuel tank.
6. If the engine does not start even though there is adequate fuei flow
from the fuel line, the fuel inlet needle valve and the seat may be gummed
together and prevent adequate fuel flow into the float bowl or EFI vapor
separator tank.
7. Ifa section of line is suspect as clogged, disconnect both ends and
use compressed air to blow through the line checking for flow or
obstructions. Though you may be able to clear some blockage using
compressed air, it's usually a better idea to replace such a fuel hose.
Checking the Primer Bulb
See Figures 15,17 and 31
The way most outboards are rigged, fuel will evaporate from the system
during periods of non-use (at least from the non high-pressure system on
carburetor motors and that portion of the system on EFI motors). Also,
anytime quick-connect fittings on portable tanks are removed, there is a
chance that small amounts of fuel will escape and some air will make it into
the fuel lines. For this reason, outboards are normally rigged with some
method of priming the fuel system through a hand-operated pump (primer
bulb).
When squeezed, the bulb forces fuel from inside the bulb, through the
one-way check valve toward the motor filling the carburetor float bowl(s) or
EFI vapor separator tank with the fuel necessary to start the motor. When
the bulb is released, the one-way check valve on the opposite end (tank side
of the bulb) opens under vacuum to draw fuel from the tank and refill the
bulb.
When using the bulb, squeeze it gently as repetitive or forceful pumping
may flood the carburetor(s) though we can't imagine it would do anything
harmful with EFI motors, as the bulb would probably just get too hard to
squeeze past a certain point). The bulb is operating normally if a few
squeezes will cause it to become firm, meaning the float bowlltank is full,
and the float valve is closed. If the bulb collapses and does not regain its
shape, the bulb must be replaced.
For the bulb to operate properly, both check valves must operate properly
and the fuel lines from the check valves back to the tank or forward to the
motor must be in good condition (properly sealed). To check the bulb and
check valves use hand operated vacuumlpressure pump (available from
most marine or automotive parts stores):
1. Remove the fuei hose from the tank and the motor, then remove the
clamps for the fittings or quick-connect valves at the ends of the hose.
Most fuel fittings and quick-connect valves are secured to the fuel
supply hose using disposable plastic ties that must be cut and
discarded for removal. If equipped, spring-type or threaded metal
clamps may be reused, but be sure they are in good condition first. Do
not over-tighten threaded clamps and crack the valve or cut the hose.
Fig. 31 Most primer bulbs contain an arrow that indicates the
direction of fuel flow (points toward the motor)
2. Carefullv remove the fittina or auick-connect valve from the motor
side of the fuel line, then place the endof the line into the filler opening of
the fuel tank. Gently pump the primer bulb to empty the hose into the fuel
tank.
M Be careful when removing the fitting or quick-connect valve from
the fuel line as fuel will likely still be present in the hose and will
escape (drain or splash) if the valve is jerked from the line. Also, make
sure the primer bulb is empty of fuel before proceeding.
3. Next, remove the fitting or quick-connect valve from the tank side of
the fuel line, draining any residual fuel into the tank.
M For proper orientation during testing or installation, the primer bulb
is marked with an arrow that faces the engine side check valve.
4. Securely connect the pressure pump to the hose on the tank side of
the primer bulb. Using the pump, slowly apply pressure while listening for air
escaping from the end of the hose that connects to the motor. If air escapes,
both one-way check valves on the tank side and motor side of the prime bulb
are opening.
5. If air escapes prior to the motor end of the hose, hold the bulb, check
valve and hose connections under water (in a small bucket or tank). Apply
additional air pressure using the pump and watch for escaping bubbles to
determine what component or fitting is at fault. Repair the fitting or replace
the defective hoselbulb component.
6. If no air escapes, attempt to draw a vacuum from the tank side of the
primer bulb. The pump should draw and hold a vacuum without collapsing
the primer bulb, indicating that the tank side check valve remained closed.
7. Securely connect the pressure pump to the hose on the motor side of
the primer bulb. Using the pump, slowly apply pressure while listening for air
escaping from the end of the hose that connects to the motor. This time, the
check valve on the tank side of the primer bulb should remain closed,
preventing air from escaping or from pressurizing the bulb. If the bulb
pressurizes, the motor side check valve is allowing pressure back into the
bulb, but the tank side valve is operating properly.
8. Replace the bulb andlor check valves if they operate improperly.
SERVICE
SY
e See Figures 27,31,32 and 33
Whenever work is performed on the fuel system, check all hoses for wear
or damage. Replace hoses that are soft and spongy or ones that are hard
and brittle. Fuel hoses should be smooth and free of surface cracks, and
thev should definitely not have split ends (there's a bad hair ioke in there, but
wewon't sink that low). Do not cut the split ends of a hose and attempt to
reuse it. whatever caused the solit host likelv time and deterioration! will
cause the new end to follow soon. Fuel hoses are safety items, don'tscrimp
on them, instead, replace them when necessary. If one hose is too old,
check the rest, as they are likely also in need of replacement.
M When replacing fuel lines, make sure the inside diameter of the fuel
hose and fitting is of sufficient size (generally 5/16 in.18mm or 318
in.19.5mm but use the original boat rigging as a starting point). Also, be
certain to use only marine fuel line the meets or exceeds United States
Coast Guard (USCG) A1 or B1 guidelines.
Check
Fig. 32 Use two picks, punches or other small tool to replace
quick-connect O-rings. One to push the valve and the other work
the O-ring free
Fig. 33 A squeeze bulb kit usually includes the bulb, 2 check
valves, and two tie straps
When replacing fuel lines only use Suzuki replacement hoses or other
marine fuel supply lines that meet United States Coast Guard (USCG)
requirements A1 or B1 for marine applications. All lines must be of the same
inner diameter as the original to prevent leakage and maintain the proper
seal that is necessary for fuel system operation.
M Using a smaller fuel hose than specified could cause fuel starvation
problems leading to misfiring, hesitation, rough idling and possibly
even engine damage.
The USCG ratings for fuel supply lines have to do with whether or not the
lines have been testing regarding length of time it might take for them to
succumb to flame (burn through) in an emergency situation. A line is "A
rated if it passes spec,?: rsq~Tements regarding burn-through times, while
B"rated lines are not tested in this fashion. The A1 and B1 lines (normally
recommended on Suzuki applications) are capable of containing liquid fuel at
all times. The A2 and 82 rated lines are designed to contain fuel vapor, but
not liquid.
To help prevent the possibility of significant personal injury or death,
" rated lines when "A" rated lines are required.
Similarly, do not use "A2" or "B2" lines when "AT or "A2" lines are
specified.
Various styles of fuel line clamps may be found on these motors. Many
applications will simply secure lines with plastic wire ties or special plastic
locking clamps. Although some of the plastic locking clamps may be
released and reconnected, it is usually a good idea to replace them.
Obviously wire ties are cut for removal, which requires that they be replaced.
Some applications use metal spring-type clamps, that contain tabs which
are squeezed allowing the clamp to slid up the hose and over the end of the
fitting so the hose can be pulled from the fitting. Threaded metal clamps are
nice since they are very secure and can be reused, but do not over-tighten
threaded clamps as they will start to cut into the hose and they can even
damage some fittings underneath the hose. Metal clamps should be replaced
anytime they've lost tension (spring type clamps), are corroded, bent or
otherwise damaged.
The best way to ensure proper fuel fitting connection is to use the
same size and style clamp that was originally installed (unless of
course the "original" clamp never worked correctly, but in those cases,
someone probably replaced it with the wrong type before you ever saw
it).
When replacing hoses and/or clamps, be sure to pay attention to the
amount of hose that extends over the fitting (though it can vary with the type
If equipped, disconnect the negative battery cable ANYTIME work is
performed on the engine, especially when working on the fuel system.
This will help prevent the possibility of sparks during service (from
accidentally grounding a hot lead or powered component). Sparks
could ignite vapors or exposed fuel. Disconnecting the cable on
electric start motors will also help prevent the possibility fuel spillage if
an attempt is made to crank the engine while the fuel system is open.
Fuel leaking from a loose, damaged or incorrectly installed hose or
fitting may cause a fire or an explosion. ALWAYS pressurize the fuel
system and run the motor while inspecting for leaks after servicing any
component of the fuel system.
All of the carbureted motors covered by this manual except one engine
family are equipped with ONE single-barreled carburetor to feed an airlfuel
mixture to the combustion chamber(s). The one exception is the 25/30 hp 3-
cylinder motor which uses THREE single-barreled carburetors.
This means that for all single cylinder and three cylinder motors each
cylinder has its own carburetor throaufloat bowl assembly, however since all
of the twin cylinder motors covered here have one, single-barreled
carburetor, their two cylinders have to share the carb.
of hose you're typically looking for about an inch or 25.4mm of hose beyond
the raised portion of the fitting). Also, make sure the clamp is seated on the
hose, about 0.1-0.3 in. (3-7mm) from the end of the hose.
To avoid leaks, replace all displaced or disturbed gaskets, O-rings or
seals whenever a fuel system component is removed.
On most installations that use quick-connects, the fuel line is provided
with quick-disconnect fittings at the tank and at the powerhead. If there is
reason to believe the problem is at the quick-disconnects, the hose ends can
be replaced as an assembly, or new O-rings may be installed. A supply of
new O-rings should be carried on board for use in isolated areas where a
marine store is not available (like dockside, or worse, should you need one
while on the water). For a small additional expense, the entire fuel line can
be replaced and eliminate this entire area as a problem source for many
future seasons. (If the fuel line is replaced, keep the old one around as a
spare, just in case).
If a quick-connect O-ring must be replaced, use two small punches, picks
or similar tools, one to push down the check valve of the connector and the
other to work the O-ring out of the hole. Apply just a drop of oil into the hole
of the connector. Apply a thin coating of oil to the surface of the O-ring. Pinch
the O-ring together and work it into the hole while simultaneously using a
punch to depress the check valve inside the connector.
The primer squeeze bulb can be replaced in a short time. A squeeze bulb
assembly kit, complete with the check valves installed, may be obtained from
the local Suzuki dealer. The replacement kit will also include two tie straps or
clamps (depending upon the manufacturer) to secure the bulb properly in the
line.
An arrow is clearly visible on the squeeze bulb to indicate the direction of
fuel flow. The squeeze bulb must be installed correctly in the line because
the check valves in each end of the bulb will allow fuel to flow in only one
direction. Therefore, if the squeeze bulb should be installed backwards, in a
moment of haste to get the job done, fuel will not reach the carburetor or EFI
vapor separator tank.
To replace the bulb, first unsnap the clamps on the hose at each end of
the bulb. Next, pull the hose out of the check valves at each end of the bulb.
New clamps are included with a new squeeze bulb.
If the fuel line has been exposed to considerable sunlight, it may have
become hardened, causing difficulty in working it over the check valve. To
remedy this situation, simply immerse the ends of the hose in boiling water
for a few minutes to soften the rubber. The hose will then slip onto the check
valve without further problems. After the lines on both sides have been
installed, snap the clamps in place to secure the line. Check a second time
to be sure the arrow is pointing in the fuel flow direction, towards the
powerhead.
The entire system essentially consists of a fuel tank, at least one filter, a
fuel su~olv line, and for all except the 2.5 ho motor, a mechanical fuel oumo
a~sembi~mounted '
to the powerhead. ~egardless, on all motors, the fuel
delivery system is designed to feed the carburetor(s) with the fuel necessary
to power the motor.
Cold start enrichment is achieved through various means on the different
carbureted Suzuki motors covered here. The means include a manual or
electric choke plate (used on most motors) and a manual or electric primer
(used on a late-model Keihin carburetor equipped 9.9115 hp and 25 hp V2
motors). Manual means of cold start enrichment are normally found on Tiller
models, especially the rope starts, though some electric start models may
also use electric chokes or primers. Remote start models almost always
utilize an electric form of cold start enrichment. Of course, we list the .
standard forms here, but at time of rigging (or repair) it is very easy to
replace one system with the other, so in the end you must determine for
yourself how the particular motor on which you are working is set-up.
For information on fuels, tanks and lines please refer to the sections on
Fuel System Basics and Fuel Tanks and Lines.
The most important fuel system maintenance that a boat owner can
~erform is to stabilize fuel su~olies before aliowina the svstem to sit idle for
anv ienath of time more thana few weeks. The next most important item is
to provide the system with fresh gasoline if the system has stood idle for any
length of time, especially if it was without fuel system stabilizer during that
time.
If a sudden increase in gas consumption is noticed, or if the engine does
not perform properly, a carburetor overhaul, including cleaning or
replacement of the fuel pump may be required.
See Figures 34 and 35
BASIC FUNCTIONS
The Role of a Carburetor
See Figures 34 and 35
The carburetor is merely a metering device for mixing fuel and air in the
proper proportions for efficient engine operation. At idle speed, an outboard
engine requires a mixture of about 8 parts air to 1 part fuel. At high speed or
under heavy duty service, the mixture may change to as much as 12-13
parts air to 1 part fuel.
Carburetors are wonderful devices that succeed in relatively precise
airlfuel mixture ratios based on tiny passages, needle jets or orifices and the
variable vacuum that occurs as engine rpm and operating conditions vary.
Because of the tiny passages and small moving parts in a carburetor (and
the need for them to work precisely to achieve proper airlfuel mixture ratios)
it is important that the fuel system integrity is maintained, introduction of
water (that might lead to corrosion), debris (that could clog passages) or
even the presence of un-stabilized fuel that could evaporate over time can
cause big problems for a carburetor. Keep in mind that when fuel evaporates
it leaves behind a gummy deposit that can clog those tiny passages,
preventing the carburetor (and therefore preventing the engine) from
operating properly.
Float Systems
See Figures 34 and 35
Ever lift the tank lid off the back of your toilet. Pretty simple stuff once you
realize what's going on in there. A supply line keeps the tank full until a valve
opens allowing all or some of the liquid in the tank to be drawn out through a
passage. The dropping level in the tank causes a float to change position,
and, as it lowers in the tank it opens a valve allowing more pressurized liquid
from the supply line back into the tank to raise levels again. OK, we were
talking about a toilet right, well yes and no, we're also talking about the float
bowl on a carburetor. The carburetor uses a more precise level, uses
vacuum to draw out fuel from the bowl through a metered passage (instead
of gravity) and, most importantly, stores gasoline instead of water, but
otherwise, they basically work in the same way.
A small chamber in the bottom of the carburetor serves as a fuel reservoir.
Afloat valve admits fuel into the reservoir to replace the fuel consumed by
the engine.
Fuel level in each chamber is extremely critical and must be maintained
accurately. Accuracy is obtained through proper adjustment of the float. This
adjustment will provide a balanced metering of fuel to each cylinder at all
speeds. Improper levels will lead to engine operating problems. Too high a
level can promote rich running and spark plug fouling, while excessively low
float bowl fuel levels can cause lean conditions, possibly leading to engine
damage.
Following the fuel through its course from carburetor float bowl to the
combustion chamber of the cylinder, will provide an appreciation of exactly
what is taking place. At the carburetor, fuel from the pump or fuelloil mixing
unit passes through the inlet passage to the needle and seat, and then into
the float chamber (reservoir). Afloat in the chamber rides up and down on
the surface of the fuel. After fuel enters the chamber and the level rises to a
predetermined point, a tang on the float closes the inlet needle and fuel
entering the chamber is cutoff. When fuel leaves the chamber as the
powerhead operates, the fuel level drops and the float tang allows the inlet
needle to move off its seat and fuel once again enters the chamber. In this
manner a constant reservoir of fuel is maintained in the chamber to satisfy
the demands of the engine at all speeds.
A fuel chamber vent hole is normally located near the top of the
carburetor body to permit atmospheri~pressure to act against the fuel in
each chamber. This pressure assures an adeauate fuel supply to the various
operating systems of the engine. But it also allows fuel to evaporate over
time, potentially leaving behind clogging deposits.
Idle and
Throttle
slow speed
valve
,orifices ,Air intake
\
Float chamber
vent& ring
/
High speed orifice
Fig. 34 Fuel flow through the venturi, showing principle and related
parts controlling intake and outflow (carburetor with manual choke
circuit shown)
Induced
low air
pressure
\
Atmospheric air pressure
Fig. 35 Air flow principle of a modern carburetor, demonstrates
how the low pressure induced behind the venturi draws fuel
through the high speed nozzle
AirIFuel Mixture
 See Figures 34 and 35
A suction effect is created every OTHER time the piston moves downward
in a 4-stroke motor (each time the piston moves downward on the intake
stroke, with the intake valve open). This suction draws air through the intake
valve and through the throat of the carburetor. A restriction in the throat,
called a venturi, controls air velocity and has the effect of reducing air
pressure at this point.
The difference in air pressures at the throat and in the fuel chamber,
causes the fuel to be pushed out metering jets extending down into the fuel
chamber. When the fuel leaves the jets, it mixes with the air passing through
the venturi. This airlfuel mixture should then be in the proper proportion for
burning in the cylinderls for maximum engine performance.
In order to obtain the proper airlfuel mixture for all engine speeds, high-
and low-speed orifices or needle valves are installed. On most modern
powerheads the high-speed needle valve has been replaced with a fixed
high-speed orifice (to more discourage tampering and to help maintain
proper emissions under load). There is no adjustment with the orifice type.
The needle valves are used to compensate for changing atmospheric
conditions. The low-speed needles, on the other hand, are often still
provided (even if they are usually hidden under plugs to discourage
tampering) so that airlfuel mixture can be precisely adjusted for idle
conditions other than what occurs at atmospheric sealevel. Although the low
speed needle should not normally require periodic adjustment, it can be
adjusted to compensate for high-altitude (riverllake) operation or to adjust for
component wear within the fuel system.
Both the manufacturer and the EPA greatly discourage any form of
tampering with factory settings on these motors. You have been
warned!
Powerhead operation at sea level compared with performance at high
altitudes is quite nonceaoie. A throttle valve controls the volume of airlfuel
mixture drawn into the powerhead. A cold engine requires a richer fuel
mixture to start and during the brief period it is warming to normal operating
temperature. Either a choke valve is placed ahead of the metering jets and
venturi to restrict the amount of air provided for starting and while the engine
is cold (defacto making the amount of fuel in a higher ratio), or an
enrichment system is used to provide extra fuel (with the normal amount of
air) through additional passages.
When the choke valve is closed or the enrichment system is actuated, a
very rich fuel mixture is drawn into the engine. This mixture will help wake-up
a cold motor, but will quickly foul the plugs on a warm engine so it should
only be used for cold starts and for running until the motor comes up to
operating temperature.
The throat of the carburetor is usually referred to as the "barrel."
Carburetors installed on engines covered here generally have a single
metering jet with a single throttle and, if used, a single choke plate. Single
barrel carburetors are fed by one float and chamber.
So, as far as carburetors go, these are relatively easy carburetors to
understand, rebuild or adjust.
COMMON PROBLEMS
The last step of fuel system troubleshooting is to adjust or to rebuild and
then adjust the carburetor. We say it is the last step, because it is the most
involved repair procedures on the fuel system and should only be performed
after all other possible causes of fuel system trouble have been eliminated.
A wise man once said that 90% of all fuel system problems are
actually ignition system problems. And another 5% are usually bad or
contaminated fuel or problems with fuel delivery. It's VERY rare that the
carb is the problem UNLESS you've allowed the motor to be stored for
long periods of time and then run it with bad gas.
Fuel Delivery
+ See Figures 36 and 37
Many times fuel system troubles are caused by a plugged fuel filter, a
defective fuel pump, or by a leak in the line from the fuel tank to the fuel
pump. Aged fuel left in the carburetor and the formation of varnish could
cause the needle to stick in its seat and prevent fuel flow into the bowl. A
defective choke may also cause problems. Would you believe, a majority of
starting troubles, which are traced to the fuel system, are the result of an
empty fuel tank or aged fuel?
If fuel delivery problems are suspected, refer to the testing procedures
under Fuel Tank and Lines to make sure the tank vent is workina ~rooerlv
, ,
and that there are no leaks or restrictions that would prevent fuel from
getting to the pump andlor carburetor(s).
A blocked low-pressure fuel filter causes hard starting, stalling, misfire or
poor performance. Typically the engine malfunction worsens with increased
engine speed. This filter prevents contaminants from reaching the low-
pressure fuel pump. Refer to the Fuel Filter in the section on Maintenance
and Tune-up for more details on checking, cleaning or replacing fuel filters.
Sour Fuel
+ See Figure 5
Fuel will begin to sour in a matter of weeks, and within a couple of
months, will cause engine starting problems. Therefore, leaving the motor
setting idle with fuel in the carburetor, lines, or tank during the off-season,
often results in very serious problems. A fuel additive such as [email protected] may
be used to prevent gum from forming during storage or prolonged idle
periods.
Refer to the information on Fuel System Basics in this section, specifically
the procedure under Fuel entitled Checking for Stalelcontaminated Fuel will
provide information on how to determine if stale fuel is present in the system.
If draining the system of contaminated fuel and refilling it with fresh fuel does
not make a difference in the problem, look for restrictions or other problems
with the fuel delivery system. If stale fuel was left in the tanklsystem for a
long period of time and evaporation occurred, there is a good chance that
the carburetor is gummed (tiny passages are clogged by deposits left behind
when the fuel evaporated), if no fuel delivery problems are found, the
carburetor(s) should be removed for disassembly and cleaning,
@ Although there are some commercially available fuel system
cleaning products that are either added to the fuel mixture or sprayed
into the carburetor throttle bores, the truth is that although they can
provide some measure of improvement, there is not substitute for a
thorough disassembly and cleaning. The more fuel which was allowed
to evaporate, the more gum or varnish that may have been left behind
and the more likely that only a disassembly will be able to restore
proper performance.
ChokeIEnrichment Problems
See Figure 38
When the engine is hot, the fuel system can cause starting problems.
After a hot engine is shut down, the temperature inside the fuel bowl may
rise to 20VF (94OC) and cause the fuel to actually boil. All carburetors are
vented to allow this pressure to escape to the atmosphere. However, some
of the fuel may percolate over the main nozzle.
If the choke should stick in the open position or the enrichment circuit
(manual or electric) fail to operate while the engine is cold, it will be hard to
start. Likewise, if the choke should stick in the closed position or the
Fig. 36 Suzuki motors use a mechanically Fig. 37 .,.or to the cylinder headlvalve Fig. 38 Fouled spark plug, possibly caused
operated fuel pump mounted to the side of cover, where it can be actuated by the by over-choking or a malfunctioning
the crankcase directlv. . . camshaft enrichment circuit
enrichment circuit remains activated during normal engine operating
temperatures, the engine will flood making it very difficult to start or, once
started, making it buck or hesitate, especially at lower speeds.
In order for this raw fuel to vaporize enough to burn, considerable air must
be added to lean out the mixture. Therefore, one remedy is to make sure the
choke is open or the enrichment circuit is off and open the throttle to the fully
open position (to allow in maximum air) and hold it there while the engine is
cranked. If this doesn't work, the only remedy remaining is to remove the
spark plugs and ground the leads, then crank the powerhead through about
ten revolutions to blow out raw fumes. Then, clean the plugs; install the
plugs again; and start the engine.
If the needle valve and seat assembly is leaking, an excessive amount of
fuel may enter the intake manifold in the following manner: After the
powerhead is shut down, the pressure left in the fuel line will force fuel past
the leaking needle valve. This extra fuel will raise the level in the fuel bowl
and cause fuel to overflow into the intake manifold.
A continuous overflow of fuel into the intake manifold may be due a
defective float or over priming the system using the primer bulb which would
cause an extra high level of fuel in the bowl and overflow into the intake
manifold.
Rough Engine Idle
Ifa powerhead does not idle smoothly, the most reasonable approach to
the problem is to perform a tune-up (remember, we said about 90% of all fuel
problems are really ignition problems) to eliminate such areas as faulty spark
plugs and timing or synchronization out of adjustment.
Other problems that can prevent an engine from running smoothly include
an air leak in the intake manifold or uneven compression between the
cylinders.
Of course any problem in the carburetor affecting the airlfuel mixture will
also prevent the engine from operating smoothly at idle speed. These
problems usually include too high a fuel level in the bowl; a heavy float;
leaking needle valve and seat; defective choke or enrichment circuit; and
improper idle (low-speed) needle valve adjustments.
'Sour" fuel (fuel left in a tank without a preservative additive) will cause an
engine to run rough and idle with great difficulty.
As with all troubleshooting procedures, start with the easiest items to
checklfix and work towards the more complicated ones.
Excessive Fuel Consumption
See Figures 39 and 40
Excessive fuel consumption can result from one of three conditions, or a
combination of all three.
1. Inefficient engine operation.
2. Damaged condition of the hull, outdrive or propeller, including
excessive marine growth.
3. Poor boating habits of the operator.
If the fuel consumption suddenly increases over what could be considered
normal, then the cause can probably be attributed to the engine or boat and
not the operator (unless heishe just drastically changed the manner in which
the boat is operated).
Marine growth on the hull can have a very marked effect on boat
performance. This is why sail boats always try to have a haul-out as close to
race time as possible. While you are checking the bottom take note of the
propeller condition. A bent blade or other damage will definitely cause poor
boat performance.
If the hull and propeller are in good shape, then check the fuel system for
possible leaks. Check the line between the fuel pump and the carburetor
while the engine is running and the line between the fuel tank and the pump
when the engine is not running. A leak between the tank and the pump many
times will not appear when the engine is operating, because the suction
created by the pump drawing fuel will not allow the fuel to leak. Once the
engine is turned off and the suction no longer exists, fuel may begin to leak.
If a minor tune-up has been performed and the spark plugs and engine
timingisynchronization are properly adjusted, then the problem most likely is
in the carburetor, indicating an overhaul is in order. Check for leaks at the
needle valve and seat. Use extra care when making any adjustments
affecting the fuel consumption, such as the float level.
Engine Surge
If the enaine operates as if the load on the boat is beina constantly
increased and decreased, even though an attempt is being made to hold a
constant enaine soeed. the oroblem can most likelv be attributed to the fuel
pump. ~eferto ~uel ~ankand Lines in this sectionfor information on
Fig. 39 Marine growth on the lower unit will create "drag" and
seriously hamper boat performance
Fig. 40 Hub and/or propeller damage will also cause poor
performance
checking the lines for restrictions and checking fuel flow. Also, refer to Fuel
Pump under Carbureted Fuel System for more information on fuel pump
operation and service.
This section provides complete detailed procedures for removal and
installation (including initial bench adjustments), overhaul
(disassembly/assembly) and cleaning and inspecting, for the various
carburetors installed on powerheads covered in this manual. Although there
are similarities between the carburetors used on each motor, small
differences from model-to-model make it best to cover them in multiple
procedures, sorted by the models on which that carburetor is found.
SERVICE (REMOVAL. OVERHAUL & INSTALLATIONS
B Good shop practice dictates a carburetor repair kit be purchased
and new parts be installed any time the carburetor is disassembled.
Make an attempt to keep the work area clean and organized. Be sure to
cover parts after they have been cleaned. This practice will prevent foreign
matter from entering passageways or adhering to critical parts.
Be sure to have a rag handy to catch spilled fuel, as some fuel is bound
to still be present in the lines and the float bowl. Take this opportunity to
closely inspect the fuel lines and replace any that are damaged or
deteriorated.
During removal or overhaul procedures, always matchmark hoses or
connections prior to removal to ensure proper assembly and installation.
Following a rebuild a complete and the initial bench settings, perform the
complete Timing and Synchronization procedure as detailed in the
Maintenance and Tune-up section.
To avoid leaks, replace all displaced or disturbed gaskets, O-rings
or seals whenever a fuel system component is removed. This is
especially true when rebuilding a carburetor.
2.5
Hp Motors
See Figure 41
This carburetor is Walbro LMJ-26 single-barrel, float feed type with a
manual choke. Fuel to the carburetor is normally gravity fed from a fuel tank
mounted at the top front of the powerhead. The carburetor contains both a
replaceable main air jet and pilot air jet, but no data is available on whether
or not it contains an adjustable pilot screw (as the factory data only says
"pre-set"), Cold start enrichment is achieved with a manual choke.
Removal & Installation
DERATE
See Figures 41 and 42
w
1. Remove the engine top cover for access.
2. Remove the spark plug lead to prevent accidental starting of the
engine. Shut off the fuel supply at the fuel valve on the side of the engine.
3. Remove the Manual Starter for access, as detailed in the Hand
Rewind Starter section.
B If you make some small marks on the throttle control inner cable
right where it enters the linkage, you may be able to skip the
adjustment procedure during installation, or at least you'll make it
quicker and easier.
4. Locate the throttle control inner cable where it connects to the throttle
lever on top of the carburetor. Loosen the screw that secures the cable.
5. Carefully detach the choke rod from the linkage on the carburetor.
IF you have enough room to get at the fuel line, you may want to
skip ahead one step and disconnect it BEFORE you remove the
carburetor bolts. If you don't have enough room, you MAY be able to
remove one of the bolts, and loosen the other, then pivot the carb
slightly for access (this can be easier than holding the carburetor while
also trying to disconnect the fuel line, as Suzuki recommends).
6. Loosen the 2 bolts that secure the air intake silencer and carburetor
assembly. Once the bolts are free, separate the air intake silencer and put it
aside, but hold the carburetor in position until you can disconnect the fuel
line.
7. Place a small shop rag under the fuel line connection at the
carburetor (to catch any escaping fuel still in the line), then squeeze the tabs
on the fuel line spring-type clamp and slide the clamp back up the fuel line
until it is past the fuel inlet nipple. Carefully and gently twisffpull the hose
from the carburetor.
8. Remove and discard the old carburetor-to-intake manifold gasket.
Also, it appears that there may be some bushings that install between the
carburetor and air intake silencer (through which the retaining bolts are
inserted), so if used, make sure they are in position and in good condition.
To install:
H Install the carburetor gasket dry. Do not use sealer. AND, DO NOT
reuse the old gasket.
9. Use the two mounting bolts to loosely hold the air intake silencer and
carburetor together as an assembly.
10. Connect the fuel tank supply hose to the carburetor and secure to
the fitting using the spring clamp.
11. Place the NEW carb-to-intake gasket over the ends of the mounting
bolts (which were installed through the air intake silencer and carburetor
assembly earlier), then position the assembly to the intake manifold and
lightly thread the bolts. Once you're sure everything is properly aligned and
the gasket is seated, tighten the bolts to 89 inch lbs.17 ft. Ibs. (10 Nm).
12. Install/adjust the throttle cable to the top of the carburetor as follows:
a. Fully close the throttle control grip.
Idle Adjusting Screw
a-Float Chamber
Gasket
Main Nozzle
Main Jet
-Float
3rain
screw
G-asket
-Bolt
Fig. 41 Exploded view of the carburetor assembly -2.5 Hp Motors
1 Fig. 42 Exploded view of the carburetor mounting -2.5 Hp Motors
b. Loosen the spring loaded idle adjusting screw (next to the throttle
lever) COUNTERCLOCKWISE until the screw does NOT touch the stopper
olate anvmore (doesn't hold the throttle ooen at all). This steo is NOT
'
bm~letilvnecessary if you made matchmarks.
' c. insert the throttle control inner cable into the hole provided in the
linkage. If you made matchmarks earlier, insert it the exact same distance
and tighten the screw to secure it. If you didn't make matchmarks, insert the
cable sufficiently to take up any play but not so tight as to start holding the
throttle open on its own.
d. If the idle screw was disturbed, you'll have to remember to check and
adjust idle later.
13. Reconnect the choke linkage to the carburetor.
14. Install the manual starter assembly.
15. Turn the fuel valve ON and allow the carburetor to suitably prime.
16. Check engine idle speed and adjust, as necessary. For details, refer
to the procedures found under Timing and Synchronization in the
Maintenance & Tune-up section. Also use this opportunity to check for fuel
leaks.
17. Shut the powerhead down when finished, then install the engine
cover.
Overhaul
 See Figure 41
1. Remove the spring loaded idle adjusting screw from the top of the
carburetor (right next to the throttle lever).
2. Remove the 4 Phillips screw at the corners of the carburetor top,
then remove the carburetor top plate and gasket.
3. With the plate out of the way, locate and remove the main jet, the
pilot air jet and the larger screw which is threaded over top of the pilot jet.
With the screw out of the way, remove the pilot jet.
4. Position the carburetor over a small drain basin, then remove the
float bowl drain screw from the bottom side of the carburetor and drain any
fuel remaining in the bowl.
5. Remove the 1 large float chamber (bowl) retaining bolt (and bolt
gasket, which should be replaced during installation), then turn the
carburetor upside down and carefully lift the float chamber from the
carburetor body.
Take care not to damage the float chamber gasketlo-ring, as it can
be reused if undamaged.
6. Remove the float pin (from right to LEFT when looking at the inverted
carburetor with the pin bosses positioned closer to you than the float). Once
the pin is freed, remove the float and float spring, noting the position of the
spring (the coiled portion goes over the end of the pin. while one arm goes
under the float and the other arm wraps around the carburetor boss through
which the pin is installed. If necessary, carefully separate the needle valve
from the float.
7. From the bore at the underside center of the carburetor body remove
the main jet, followed by the main nozzle.
8. Thoroughly clean and visually check all of the carburetor components
as detailed under Cleaning & Inspection in this section,
To assemble:
9. Before starting, make sure all components are completely clean and
serviceable. Compare parts from the replacement kit to the parts removed
from the carburetor. With the exception of wear or damage that might occur
on the old parts (requiring their replacement in the first place) the new
components should be identical. If you have any questions, check with a
local dealer to check parts against a current part catalog before proceeding.
To ensure proper operation and durability, replace all displaced or
disturbed aaskets, 0-rinas or seals when rebuildina a carburetor
-
regardlessof their appearance.
Do NOT over-tighten needles or jets as this will likely cause distortion
and problems with airlfuel metering.
10. Install the main nozzle to the bore in the center, underside of the
carburetor body, then install carefully and gently the main jet.
11. If removed, install a new float chamber gasketlo-ring to the groove in
the underside of the carburetor body.
12. Carefully position the needle valve to the float, then lower the
combination onto the carburetor throttle body positioning the float spring and
the hinge pin. Remember to install the hinge pin from the left side boss
(when looking straight on at both hinge bosses, with the bosses facing you
and the float facing away).
13. Make sure the float moves smoothly, then position the carburetor on
its side so the needle is closed BUT the weight of the float IS NOT APPLIED
to the valve. Use a pair of vernier calipers with a depth gauge to measure
the distance from the bottom of the float to the float chamber mating surface
of the carburetor body. The float height should be 0.31-0.47 in. (8-12mm)
14. Install float chamber using the bolt and a NEW bolt gasket, then
tighten the bolt securely. Make sure the drain screw, if removed, is also
installed securely.
15. Moving to the top of the carburetor install the pilot jet followed by the
plug that goes in the bore above it, then install the pilot air jet to the smaller
bore right next to it, and toward the opposite side of the carburetor install the
main air jet.
16. Install the carburetor cover using a new gasket, and tighten the
screws securely.
17. Install the idle adjusting screw.
18. Install the carburetor as detailed earlier in this section.
19. Adjust the idle speed as detailed under the Engine Maintenance
section.
41516 Hp Motors
@ See Figures 43 and 44
There are 2 slightly different versions of the carburetors used on this
manual. Both are a single-barrel, float feed type with fixed main jets and a
manual choke. However, there are differences in the Mikuni carburetor
bodies used through mid-2004 and the Keihin carburetor bodies used
starting in mid-2004 and on all 2005 and later models. However, since the
carburetors are functionally almost identical, the differences are only
important when servicing them or replacing parts.
The quick and easy way to tell the difference is that the Mikunis
have a rounded float bowl which is secured by a single large bolt at She
bottom center of the bowl. while Keihins have a rounded bowl with a
square flange that is secured by 4 screws.
Although, keep in mind that it is always possible that a carburetor from a
different year could have wound up on any given motor or for motors in
different markets, so visually confirm the carburetor on which you are
working using the accompanying exploded views.
The other main difference between the two is that an adjustable pilot
screw is normally found on the top side of the Mikuni carbs (though it might
be cappedlsealed on some versions), while the Suzuki literature doesn't
even SHOW a screw on the Keihins (though it must be there and capped
since some markets show a pilot jet setting).
The final difference is in the location of the pilot and main jets. The Mikuni
carburetor body places a pilot jet vertically on the same side as the pilot
screw (which is the opposite side of the throttle stop screw) and the main jet
in the lower, front end of the carburetor body. On Keihin carbs the pilot jet
has been moved and is mounted at an angle downward on the same side as
the throttle stop screw, and the main jet has been relocated into the
underside of the carburetor body, just above the nozzle.
Removal& Installation
DERATE
v
@ See Figures 43 thru 49
The accompanying photos are from a Mikuni equipped test motor.
Keihins should be similar, but NOT identical.
1. Remove and ground the spark plug lead to prevent any accidental
attempt at starting of the engine.
If you mark the throttle control inner cable before removal to show
how far it is inserted through the linkage it will make installation a little
easier.
2. Loosen the small horizontally mounted screw that secures the throttle
control inner cable (the screw is just under the throttle tab, on the linkage at
the top of the carburetor).
3. Release the spring clamp, then remove the breather tube and
protector from the holder on the flame arrestor.
4. Release the spring clamp(s), then disconnect the fuel hose and, if
applicable the air vent [email protected]) from the carburetor fitting($. Have a rag or
small drain basin handy to drain residual fuel from the carburetor fuel hose.
5. At the top of the carburetor, disconnect the choke rod from the
linkage.
6. Loosen and remove the 2 bolts securing the flame arrester (with
holder) and the carburetor itself to the intake manifold. Carefully remove the
assembly and gasket from the intake manifold. Clean the gasket mating
surfaces of any remaining material.
To install:
Install the carburetor gasket dry. Do not use sealer. AND, DO NOT
reuse the old gasket.
7. Position a new gasket, the carburetor and the flame arrester (with the
smooth side facing outward) against the intake and thread the mounting
bolts to hold them. Or alternately, assemble the components (flame arrester,
holder, carburetor and then gasket) over the mounting bolts and use the
bolts to hold them together as you move the assembly into position against
Choke Rod
Connector
Y Throttle
Choke
Knob
aFloat
Float Bowl
Gasket
Float Bowl
"ÇH urain Screw
Float Bowl 4
Retainer
Fig. 43 Exploded view of the Mikuni carburetor assemblies used on
41516 hp motors through mid-2004
the powerhead and lightly thread the bolts. Either way, once the assembly i!
seated, tighten the 2 mounting bolts alternately and evenly to 89 inch lbs.17
ft. Ibs. (10 Nm).
8. Reconnect the choke rod to the linkage.
9. Reconnect the fuel and, if applicable,air vent hoses to the carburetor
fittings and secure using the spring clamp(s).
10. Reconnect the breather tube and protector to the flame arrestor
holder and secure using the spring clamp.
B IF you marked the inner throttle cable before removal, you can
usually avoid the part in the next step about loosening the throttle stop
(idle adjusting screw). Then again, if you've done anything significant
with carburetor (rebuilt or replaced) you'll likely have to adjust idle
speed anyway, but the choice is yours.
11. Fully close the throttle grip and turn the throttle stop (idle adjusting)
screw counterclockwise until the screw no longer touches the stopper plate.
Insert the throttle control inner cable into the linkage hole (to the same point
as was marked during removal, if it was indeed marked), then while pulling
the cable gently tighten the screw to secure the cable.
12. Gently squeeze the primer bulb while checking for fuel leakage.
Correct any fuel leaks before returning the engine to service.
13. Perform the necessary timing and synchronization procedures from
the Maintenance & Tune-up Section. If the carburetor was repaired or rebuilt
and it is an adjustable model, be sure to perform the initial low speed
adjustment procedure. Either way the idle speed needs to be set.
Overhaul
CULT
v
See Figures 43,44 and 50
B Remember, the quick and easy way to tell the difference between
the 2 types of carburetors you might find on these motors is that the
ikunis have a rounded float bowl which is secured by a single large
bolt at the bottom center of the bowl, while Keihins have a rounded
bowl with a square flange that is secured by 4 screws.
Air Vent
Hoses
Clarnp-e
xploded view of the Keihin carburetor assemblies used in
mid-2004 or later 41516 Hp Motors
1. Position the carburetor over a small drain basin, then remove the
float bowl drain screw from the bottom side of the carburetor float bowl and
drain any fuel remainina in the bowl.
2. For Mikuni models equipped with a pilot (idle mixture) screw, remove
the screw and spring from the top side of the carburetor body (threaded
downward at an angle, on same side as the pilot jet, which is on the opposite
side of the throttle stoplidle speed screw and spring. Before removing the
screw, count and record the number of turns required to lightly seat the idle
adjustment screw. The number of turns will give a rough adjustment during
installation. Back out the idle speed screw and spring from the side of the
carburetor body. Normally you discard the screw, but save the spring (a new
screw is usually provided in the carburetor rebuild kit to ensure a damaged
screw is not used again.)
On Keihin models with a pilot (idle mixture) screw, you need to
follow the same procedure as the previous step, but since the Suzuki
diagrams don't show the screw, we can't tell you where to find it.
3. For all models, locate and remove the pilot jet. On Mikuni models it is
threaded vertically into the top of the carburetor body on the same side of
the pilot screw (opposite side from the throttle stop screw), but on Keihin
models it is threaded downward at an angle (on the same side as the throttle
stop screw).
4 Invert the carburetor, then remove the float bowl retainer(s). For
Mikuni models there is a single, large bolt at the center of the bowl (along
with a gasket which should be replaced to prevent the possibility of fuel
leaks). On Keihin models there are 4 bolts (one at each corner of the bowl
mounting flange).
5. Lift the float bowl and gasket from the underside of the carburetor
body. Discard the old gasket.
The float hinge pin can only be removed in one direction these models.
And that direction varies with the type of carb (Mikuni type vs. the later
model type).
6. Position the carb upside-down (with the float facing upward) with the
float pin closest to you (and the float itself further away from you). In this
Fig. 45 Loosen the screw and disconnect ig. 46 Remove the breather tube from the Fig. 47 Disconnect the fuel line from the
the throttle cable from the linkage carb fuel inlet
CARB& "
FLAMEARRESTE
RETAINING BOLTS
Fig. 48 Disconnect the choke linkage from Fig. 49 Remove the bolts securing the flame Fig. 50 Measure float height from the edge
the carb arrester holder and carburetor of the float to the gasket mating surface
1 1
direction the float pin must be removed by pushing FROM THE LEFT SIDE
TOWARDS THE RIGHT on Mikuni model carburetors or from the RIGHT
SIDE PUSHING TOWARDS THE LEFT on Keihin model carbs. Using a
small pick or awl, carefully remove the float hinge pin, then remove the float
and float valve from the carburetor body (note that the Keihin models have a
removable clip, so don't loose track of it).
7. Remove the main orifice (high speed jet) from either the side of the
carburetor body (Mikuni models) or from the underside of the body, just
below the nozzle (Keihin models). Remove the nozzle from the underside,
center of the carb body.
8. Remove the throttle stop screw and spring mounted horizontally in
the boss on the side of the carburetor body.
9. Thoroughly clean and visually check all of the carburetor components
as detailed under Cleaning & Inspection in this section.
To assemble:
10. Before starting, make sure all components are completely clean and
serviceable. Compare parts from the replacement kit (especially the gaskets)
to the parts removed from the carburetor. With the exception of wear or
damage that might occur on the old parts (requiring their replacement in the
first place) the new components should be identical. If you have any
questions, check with a local dealer to check parts against a current parts
catalog before proceeding.
H To ensure proper operation and durability, replace all displaced or
disturbed gaskets, O-rings or seals when rebuilding a carburetor
regardless of their appearance.
11. Install the throttle stop screw and spring to the boss in the top of the
carburetor body. Thread the screw until it just contacts the idle adjustment
lever.
12. Install the fuel nozzle into the underside, center of the carburetor
body.
14. Carefully insert the float valve into the valve seat, while installing the
float using the hinge pin. Remember to install the hinge pin in the opposite
direction of which it was removed. After securing the float, check for smooth
movement of the float and needle assembly.
15. Hold the carburetor either at about a 45 degree angle with the float
hinge upward (Keihin) or completely sideways but still with the float in the
needle closed position (Mikuni), so that you can check the float height while
making sure the float WEIGHT is not applied to the needle valve. Using a
suitable vernier calipers or other instrument, measure the distance from the
float bowl gasket mating surface on the carburetor body to the parallel
surface on the bottom of the float. This measurement varies with the
yearltype of carburetor and should be 0.51-0.59 in. (13-15mm) for Mikuni
models or 0.35-0.43 in. (9-11mm) on Keihin models. If adjustment is
necessary carefully bend only the adjustment tab itself toachieve the
required measurement. But DO NOT bend it to the point that the tab applies
pressure to the needle and seat.
Be VERY careful when measuring or adjusting the float height not to
force the float needle valve downward into the seat. The valve or the
seat will likely be damaged if this occurs.
16. Install the float bowl using a new gasket and tighten the [email protected])
securely. On Mikuni models with the round bowl and the single retaining bolt,
be sure to replace the bolt gasketlwasher to help ensure there will be no fuel
leaks.
17. Install the pilot jet.
18. If equipped, install the low speed (idle) mixture screw and spring into
the top of the cover. Thread the screw slowly into the bore until it just lightly
contacts the seat, then back it off the specified number of turns listed in the
Carburetor Set-Up Specifications tableor alternately the number of turns you
13. Install the main jet. counted when you seated it before unthreading during disassembly.
19. Install the carburetor, then perform the necessary timing and
synchronization procedures from the Maintenance & Tune-up Section
(including the idle speed and, if applicable, mixture adjustments).
9.9115 Hp and 25 hp V2 Motors
@ See Figures 51 and 52
There are different versions of the carburetors used on these models. All
are single-barrel, float feed types. However the units from two different
carburetor manufacturers were used over the years and they have different
forms of cold start enrichment.
Generally speaking, through 2004 the carburetors mounted on these
powerheads were from Mikuni and they utilized either a manual choke (rope
start or tiller electric models) or the used an electric choke (remote electric
models, but optional on the tiller electrics).
Starting for the 2005 model year Suzuki switched to a different supplier,
Keihin whose carburetors utilize either a manual primer (rope start or tiller
electric) or an electric primer (remote control models). The Keihin carburetors
may or may not be equipped with an accelerator pump, depending upon the
model (though the 15 hp and 25 hp motors should normally have one).
Obviously since the 25 hp V2 was not introduced until 2006, the Keihins are
the only carburetors you would EXPECT to find on that powerhead.
We say these are the carburetors you would "expect" to find because
keep in mind that it is always possible that a carburetor from a different year
could have wound up on any given motor or for motors in different markets,
so visually confirm the carburetor on which you are working using the
accompanying exploded views.
The quick and easy way to tell the difference is that the Mikunis
have a more rounded float bowl (and once you remove it, a very
rounded float) whereas the Keihins have a squared float bowl with a
float that utilizes 2 rectangular sections.
Removal& Installation
DERATE
@ See Figures 51 thru 54 -+=-
On some of these motors (specifically 9.9115 hp motors with Keihin
carburetors) positioning of components, like the fuel line nipple on the carb,
is such that removing the carburetor and THEN disconnecting hoses, linkage
and wiring is usually easier. Parts of this procedure are therefore written that
way.
Remember that the quick and easy way to tell the difference
between the 2 types of carbs used on these powerheads is that the
Mikunis have a more rounded float bowl (and once you remove it, a
very rounded float) whereas the Keihins have a squared float bowl with
a float that utilizes 2 rectangular sections. Or looking at them another
way, the Mikunis use a choke, and the Keihins use a primer.
1. Remove the engine top cover for access.
2. For safety either tag and disconnect the spark plug leads andlor on
electric start models, disconnect the negative battery cable to prevent
accidental starting or cranking of the motor.
3. On 9.9115 hp motors remove the starboard side lower engine cover
for access. Refer to the procedure under and Engine Covers, as necessary.
4. On 25 hp motors, for access, either remove the Flywheel cover or
the Hand Rewind Starter assembly along with the air intake silencer from the
top of the powerhead (as applicable).
5. On Mikuni-equipped 9.9115 hp motors, proceed as follows:
a. On models through 2002 remove the choke knob from the end of the
rod, then tag and disconnect the breather hose from the cylinder head cover.
If it is difficult to access the fuel supply hose, the throttle and/or the
choke rod from the carburetor, simply wait until the carburetor is
unbolted, then position it as necessary for access.
b. Disconnect the fuel supply hose either from the fuel pump (that's the
method suggested through 2002) or from the carburetor inlet fitting. Have a
rag handy, as you should expect fuel to escape from the line and possibly
the carb inlet nipple. On some models (again, usually through 2002) there is
a fuel hose clamp bolted to the powerhead right underneath the
flywheel/manual starter cover, if so equipped remove the clamp and free the
fuel hose from it.
Pilot
hamber
Cap
ose
Fig. 51 Exploded view of the Mikuni carburetor generally found on
9.9115 Hp motors through 2004 (note the accelerator pump differs
slightly on some models)
c. Disconnect the throttle control rod from the carburetor. On 2003-04
models, disconnect the choke rod from the carburetor as well. On earlier
models Suzuki had you remove the choke rod along with the carburetor
which is why you pulled the knob from the end of it earlier.
d. Loosen and remove the 2 bolts securing the air intake silencer,
carburetor and insulator to the powerhead. Carefully separate the
components and hold the carburetor as you disengage the remaining
components to free it.
e. If not done earlier, disconnect the fuel hose, the throttle control rod
andlor the choke rod from the carburetor.
f. Remove the intake silencer and carburetor assembly.
6. On 9.9115 hp motors equipped with a Keihin carburetor, proceed as
follows:
a. Loosen and remove the 2 bolts securing the air intake silencer,
carburetor and insulator to the powerhead. Carefully separate the
components and hold the carburetor as you disengage the remaining
components to free it.
b. Disconnect the fuel hose from the carburetor inlet. Have a rag handy,
as you should expect fuel to escape from the line and possibly the carb inlet
nipple.
c. Disconnect the throttle rod from the carburetor.
d. On tiller models, unscrew the starter (primer) cable locknut, then
remove the cable with plunger.
e. For remote models, disconnect the wiring (usually 2 bullet
connectors) for the electric primer (auto-enrichener).
7. On 25 hp motors equipped with a Keihin carburetor, proceed as
follows:
a. On manual primer models (usually rope start models), unscrew the
starter (primer) cable locknut, and then remove the cable with plunger.
UEL SYST
1. Carburetor body
2. Main nozzle
3. Main jet
4. Pilot jet
5. Cap
6. Float
7. Needle valve
8. Needle valve pin
9. Clip
10. Pin
11. Screw
12. Stop screw
13. Spring
14. Gasket
15. Float boat
16. Drain screw
17. O-ring
18. U-ring
19. Top cover
20. Screw
21. Cable holder
22. Cable guide
23. Cable sealing cap
24. Starter valve
25. Spring
26. O-ring
27. Drain hose
28. Clip
29. Plate
30. Screw
31. Starter assy
I0
32. Clip
33. Cap
34. Plunger 15
35. Spring
36. Starter knob assy
37. Cable protector
17
n
LU-
15 HP
-or
25 HP
Only
Electric Prii Tie
Models
A Manual Prime
Models
Fig. 52 Exploded view of the Keihin carburetor generally found on 2005 or later 9.9115 Hp and 25 hp V2 motors (note that not all components are
used on all carbs)
Fig. 54 . . .you can disconnect the choke at either end (knob or
Fig. 53 View of a Mikuni carburetor with manual choke. .. carbl
1 1
b. On electric primer models (usually both Tiller Electric and Remote
Electric models), disconnect the wiring (usually 2 bullet connectors) for the
electric primer (auto-enrichener).
c. At the front of the carburetor throttle body locate the securing plate
which is bolted down to the top of the powerhead. Loosen and remove the 2
bolts which are threaded vertically downward through the plate into the
powerhead.
d. Next remove the 2 bolts which are threaded horizontally from the
securing plate through the carburetor body into the intake.
e. Remove the plate, outlet tube, carburetor, gasket, insulator and
gasket (in that order) from the intake manifold.
f. Gently reposition the carburetor for access to the fuel hose, and then
carefully free the hose from the carburetor fuel inlet.
8. lf not done earlier, remove and discard the old carburetor gasket,
then carefully clean all gasket mating surfaces of any remaining material.
To install:
install the carburetor, and if applicable, insulator [email protected]) dry. Do
not use sealer. Also DO NOT reuse an old gasket or air leakage may
result which can severely lean the mixture and damage the powerhead.
9. On Keihin-equipped models, prepare the carburetor for installation by
getting the insulator and 2 gaskets ready.
10. On 25 hp motors with a Keihin carburetor, proceed as follows:
a. Hold the carburetor in position and reconnect the hose to the
carburetor fuel inlet.
b. If not done already, install the insulator using a new gasket, making
sure that the projection on the diamond point of the insulator is faced to the
STARBOARD and INTAKE MANIFOLD sides. Next position the carburetor
gasket, the carburetor, outlet tube and plate and loosely install the 2
horizontal bolts to secure everything. Actually, we sometimes find it easier to
use the bolts to hold everything together before seating everything against
the manifold, the choice is yours.
c. Loosely install the other 2 securing plate bolts (the vertical ones), and
then tighten all 4 bolts to 89 inch lbs.17 ft. Ibs. (10 Nm),
d. On electric primer models, reconnect the wiring (usually 2 bullet
connectors) for the electric primer (auto-enrichener).
e. On manual primer models, install the starter (primer) cable and
plunger, and then tighten the locknut securely.
f. Install either the Flywheel cover or the Hand Rewind Starter
assembly, as equipped.
11. On Keihin-equipped 9.911 5 hp motors, hold the carburetor next to the
powerhead and reconnect the necessary wires, linkage andlor hoses as
follows:
a. On remote models, reconnect the wiring (usually 2 bullet connectors)
for the electric primer (auto-enrichener).
b. On tiller models, install the starter (primer) cable and plunger, then
tighten the locknut securely.
c. Connect the throttle rod from the carburetor.
d. Connect the fuel hose from the carburetor inlet.
When installing the carburetor gasket make sure the cold start fuel
passage (the small port along the rim of the throttle body) is NOT
obstructed, or expect cold start problems.
e. Position a new gasket on either side of the insulator, then position
the insulator (with the projection facing Starboard toward the intake
manifold), carburetor and air intake silencer to the powerhead, then secure
using the retaining screws. Tighten the bolts to 89 inch 1bs.F ft. Ibs. (10 Nm).
f. Make sure that all components which were disturbed have been
returned to their original positions (except the starboard lower engine cover,
as you will install that after checking for leaks).
12. On Mikuni-equipped 9.9115 hp motors, you can either hold the
carburetor next to the powerhead and reconnect the necessary wires,
linkage and/or hoses, if that was the method you used during disassembly
OR if you followed the steps recommended for 2002 and earlier models you
can put the carburetor in position and then reconnect the fuel hose etc. as
follows:
a. On models through 2002 remove the choke knob from the end of the
rod, then tag and disconnect the breather hose from the cylinder head cover.
E If it Is difficult to access the fuel supply hose, the throttle and/or the
choke rod from the carburetor, simply wait until the carburetor is
unbolted, then position it as necessary for access.
b. Loosely position the intake silencer and carburetor assembly.
c. If connecting linkage and hoses before the carburetor is secured, do
it at this time. Reconnect the choke rod andlor throttle control rod, then
reconnect the fuel hose.
d. Install the carburetor and intake silencer using a new gasket, then
carefully tighten the two retaining bolts to 89 inch Ibs.17ft. Ibs. (10 Nm).
e. if not done earlier, reconnect the throttle control rod to the carburetor.
f. If not done earlier, reconnect the fuel line to the carburetor or the fuel
pump, as applicable. If you followed the method suggested through 2002
install the fuel line to the hose clamp and secure the clamp to the powerhead
right underneath the flywheellmanual starter.
g. If applicable, reconnect the breather hose to the cylinder head cover.
h. If removed, install the choke knob to the end of the choke rod.
13. Gently squeeze the primer bulb while checking for fuel leakage.
Correct any fuel leaks before returning the engine to service.
14. On 25 hp motors, install the manual starter or flywheel cover and air
intake silencer assembly, as applicable.
15. On 9.911 5 hp motors, install the starboard lower engine cover.
16. Perform the necessary timing and synchronization procedures from
the Maintenance & Tune-up Section. If the carburetor was repaired or
rebuilt, be sure to perform the initial low speed adjustment procedure
Overhaul
CULT
See Figures 50,51and 52
Remember that the quick and easy way to tell the difference
between the 2 types of carbs used on these powerheads is that the
Mikunis have a more rounded float bowl (and once you remove it, a
very rounded float) whereas the Keihins have a squared float bowl with
a float that utilizes 2 rectangular sections. Or looking at them another
way, the Mikunis use a choke, and the Keihins use a primer.
1. Position the carburetor over a small drain basin, then remove the
float bowl drain screw from the bottom or bottom side of the carburetor and
drain any fuel remaining in the bowl. If equipped (and we know it should be
on the Keihins, but can't tell for sure on the Mikunis) discard the drain screw
O-ring and replace with a new one during assembly to prevent fuel leakage.
2. On Keihin models with an electric primer (generally only remote
models on 9.9115 hp powerheads, but usually includes both remote AND
tiller electric 25 hp motors), loosen the screw (9.9115 hp) or screws (25 hp)
on the enrichener mounting plate, then remove the enrichener assembly
from the bore on the top of the carburetor cover.
3. On Keihin models, loosen the 4 screws securing the carburetor cover
to the top of the carburetor body, then remove the cover and discard the old
gasket.
On carbs which contain a covered pilot screw the manufacturer
warns NOT to remove the cover or attempt to adjust the screw. They do
not give an explanation for this (whether or not this is IegalIEPA
related, but we have our suspicions).
4. If equipped and if desired, remove the low speed (idle mixture) screw
from the bore in the side of the carburetor cover (for Keihin models it is on
the lower left corner when you are looking at the enrichener bore in the
cover, but for Mikuni models it is on the top, side of the carburetor body just
above the roller for the throttle lever). Before removing the screw, count and
record the number of turns required to lightly seat the idle adjustment screw.
The number of turns will give a rough adjustment during installation. Back
out the idle speed screw from the side of the carburetor body.
5. Invert the carburetor so it is sitting on the top of the throttle body (on
the carburetor cover gasket mating surface for Keihin models), then remove
the 4 float bowl screws. Slowly lift the float bowl and gasket from the
underside of the carburetor body exposing the float assembly. On Keihin
carburetors equipped with an accelerator pump (usually only on 15 hp and
25 hp models) you are also exposing the pump assembly (which includes a
spring which might pop free if you're not careful). On Mikuni models, though
you're exposing the top of the pump, there is usually less of a chance of it
springing free, but use care just the same. Remove and discard the old float
bowl gasket.
6. Remove the float assembly as follows, depending upon the model:
On Mikuni models, position the carburetor with the float on top and
facing away from you so the hinge pin bosses are closest to you. Carefully
push the float pin FROM the RIGHT SIDE and OUT to the LEFT. The left
side of the pin should have a small flat on it. Carefully remove the float and
float valve. Also on these models there is a screw and tab securing the valve
seat. If necessary remove the screw, tab and seat.
On Keihin models, remove the screw securing the float pin, then
carefully remove the float hinge pin followed by the float and float valve from
the carburetor body.
7. Remove the main jet either from the bore in the center of the
carburetor body underside (Keihin) or from the bore in the front of the
carburetor (Mikuni).
8. Remove the main nozzle from the bore in the center of the carburetor
body underside. For Mikuni models you first need to remove the main jet
nozzle cap.
9. Remove the pilot jet from the carburetor body. On Keihin models it is
in the bore just off-center (next to the main jet and nozzle), remove the cap,
then remove the pilot jet. On Mikuni models it is in the bore on the side of
the carburetor body, about centered.
10. If equipped remove the accelerator pump components depending on
the carburetor as follows:
* On Mikuni carburetors the components should be installed in the bore
on the side of the float bowl. Carefully remove the 2 caps, followed by the
holder, plunger and spring. Remove and discard the old O-ring at this time.
* On Keihin carburetors (usually only on 15 hp and 25 hp models), from
the bore toward the side of the carburetor body, remove the spring and
accelerator pump plunger. On the side of the carburetor body release the
clamp and remove the rubber cap for the pump plunger.
11. Thoroughly clean and visually check all of the carburetor components
as detailed under Cleaning & Inspection in this section.
12. To check the electric primer on Keihin models so equipped, proceed
as follows:
a. Note the position of the needle, then connect it using a set of jumper
wires to a 12-volt power source.
b. Wait at least 5 minutes, while periodically checking the needle
position to see if it has changed. The needle must be visibly longer after 5
minutes or the assembly must be replaced,
13. To check the electric choke on Mikuni models so equipped, use a
DVOM to check solenoid coil resistance across the terminals for the Orange
and Black wires. At an ambient temperature of about 68OF (20%) you should
see about 2.8-4.2 ohms resistance.
To assemble:
14. Before starting, make sure all components are completely clean and
serviceable. Compare parts from the replacement kit (especially the gaskets)
to the parts removed from the carburetor. With the exception of wear or
damage that might occur on the old parts (requiring their replacement in the
first place) the new components should be identical. If you have any
questions, check with a local dealer to check parts against a current part
catalog before proceeding.
To ensure proper operation and durability, replace all displaced or
disturbed gaskets, O-rings or seals when rebuilding a carburetor
regardless of their appearance.
15. If equipped, install the accelerator pump assembly depending upon
the model as follows:
On Mikuni models make sure the NEW O-ring is in position, then install
the spring, plunger and holder. Install the large cap, followed by the small
cap.
* On Keihin models, insert the accelerator rod plunger and spring to the
bore towards the edge of the carburetor body's underside. On the side of the
pump body install the plunger cap and secure using the clamp (clip).
16. Install the pilot jet, and on Keihin models, cover it with the cap.
17. Install the main nozzle to the bore in the center of the carburetor
body underside. On Mikuni models install the main jet there next. On Keihin
models, install the cap there, then install the main jet to the front of the
carburetor.
18. If removed on Mikuni models, install the valve seat and secure using
the tab and retaining screw.
19. Carefully install the float along with the needle valve and secure
using the hinge pin. On Mikuni models, be sure to insert the pin from the
LEFT to the RIGHT side (from the same side you pulled it out of earlier). On
Keihin models, lock the hinge pin in place using the retaining screw. Turn the
carburetor over for a second and check for smooth float movement, then
position the carburetor on its side, with the needle valve closed but
WITHOUT the weight of the float on the needle valve to measure installed
float height.
20. Using a suitable vernier calipers or other instrument, measure the
distance from the float bowl gasket mating surface on the carburetor body to
the parallel surface on the bottom of the float. This measurement varies with
the carburetor and should be 0.65-0.73 in. (16.6-18.6mm) on Mikuni models
or 0.45-0.61 in. (11.5-15.5mm) on Keihin models. If adjustment is necessary
carefully bend only the adjustment tab itself to achieve the required
measurement.
Be VERY careful when measuring or adjusting the float height not to
force the float needle valve downward into the seat. The valve or the
seat will likely be damaged If this occurs.
21. Install the float bowl to the carburetor body using a new gasket.
Install the cover screws, then securely using a crossing pattern. For models
with an accelerator pump, actuate the throttle lever by hand feeling and
watching for smooth operation of the pump plunger assembly.
22. Invert the carburetor and on Keihin models, install the carburetor
cover to the carburetor body using a new gasket. Install the cover screws,
then securely using a crossing pattern.
23. If applicable and if removed, install the low speed (pilotlidle) mixture
screw and into the round boss on the side of the carburetor cover (Keihin) or
to the top, side of the carburetor body just above the roller for the throttle
lever (Mikuni). Thread the screw slowly into the bore until it just lightly
contacts the seat, then back it off the specified number of turns you counted
when you seated it before unthreading during disassembly (or alternately if
you didn't count, the number of turns listed in the Carburetor Set-Up
Specifications table in this section).
24. On Keihin models with an electric primer, install the enrichener
assembly to the bore in the carburetor cover then secure using the screw(s)
on the mounting plate.
25. On Mikuni models equipped with an accelerator pump you must
checldadjust the pump lever gap before reinstallation to ensure proper
pumplcarburetor operation. With the throttle lever fully closed there should
be a 0-5mm gap between the accelerator pump lever and the top of the
pump plunger rod. If necessary, use the spring loaded throttle lever stop
screw which contacts the throttle lever just above and to the side of the
accelerator pump plunger to adjust the gap. Keep in mind that this setting is
adjusted at the factory and should not NEED to be adjusted in normal
service, unless this screw was disturbed.
26. Install the carburetor, then perform the necessary timing and
synchronization procedures from the Maintenance and Tune-up Section
(including the idle speed and mixture adjustments).
25/30 Hp (3-Cyl) Motors
See Figure 55
These motors are equipped with a stack of 3 carburetors, each mounted
individually to a common inlet case which in turn bolts to the intake manifold
and air silencer assembly. The carburetors are removed from the powerhead
as an assembly and then freed from the inlet case (as they are secured to
the case by flange nuts).
Although small differences occur between each carburetor (such as a
dashpot attached to the top, a choke rod attached to the middle or bottom
and an accelerator pump attached to the bottom), each is of the same basic
design. Each carburetor is a single-barrel, float feed type containing both a
main air jet and main jet in bores at the front of the carburetor throttle body
as well as both a pilot jet and pilot needle valve in the side of the carb body.
These carburetors are generally equipped with either a manual or an electric
choke.
Removal& Installation
DERATE
9See Figures 55 thru 58
As noted earlier, these carburetors are mounted to a common inlet case
which in turn bolts to the intake manifold and air silencer assembly. The
carburetors are removed from the powerhead along with the inlet case as an
assembly.
1. For safety, disconnect the negative battery cable to prevent
accidental cranking of the motor.
2. Either remove the manual starter, as detailed in the Hand Rewind
Starter section, or remove the 3 bolts securing the flywheel cover, then
remove it from the top of the powerhead, depending on how the outboard is
equipped..
3. Loosen the 4 bolts securing the starboard side lower engine cover
and remove the cover for access. For more details, refer to the procedure
under and Engine Covers, in the Maintenance &Tune-up section, as
necessary.
4. Loosen and remove the 2 bolts securing the air intake silencer case
to the powerhead, then remove the 2 bolts securing the air silencer pipe to
the crankcase.
5. On Tiller models, follow the choke rod back to the side of the bottom
carburetor and locate the E-ring (retaining clip). Carefully remove the clip
and free the rod, keeping track of the gasket(s) and other clip.
6. Just in front of the fuel filter, locate and disconnect the throttle control
rod from the throttle cam.
7. Remove the bolt securing the fuel filter bracket, then
remove/reposition the bracket and the fuel filter assembly.
8. Remove the Fuel Pump, as detailed later in this section.
9. Remove the 2 nuts and 4 bolts that fasten the inlet case to the intake
manifold (threaded from the rear of the motorlintake), then slowly remove the
carburetor and inlet case assembly from the powerhead. As you pull the
assembly away carefully disconnect the fuel inlet hose from the 3-way joint
on the bottom. Have a rag handy to catch any fuel which might spill.
10. To remove the carburetors from the assembly, proceed as follows:
a. Remove the 4 bolts, then separate the air silencer case from the
assembly.
b. Remove the choke rods and the throttle link rods from each
carburetor.
c, As applicable, remove the bolts and choke solenoid (electric choke
models) and/or the carburetor protector (tiller models).
d. Loosen and remove the flange nuts for each carburetor.
e. Separate the plates, air silencer pipe, carburetors, insulators and
gaskets from the inlet case. Be sure to discard all gaskets.
To install:
Install gaskets dry. Do not use sealer. Also DO NOT reuse an old
gasket or air leakage may result which can severely lean the mixture
and damage the powerhead.
11. Assemble the carburetor and air inlet components using new
gaskets. Position the insulators with gaskets on either side, followed by the
carburetors, the air silencer gaskets, the air silencer pipe and the carburetor
plates all over the air inlet studs. Install the carburetor flange nuts to secure
everything and tighten to 89 inch lbs.17 ft. Ibs. (10 Nm).
12. Install the choke solenoid and/or carburetor protector, as equipped,
and tighten the bolts securely.
13. Install the choke rods and throttle link rods to each carburetor.
14. Install the air silencer case and secure using the 4 bolts.
15. Install the carburetor and air inlet assembly to the powerhead by first
holding the assembly almost in place and connecting the fuel inlet hose to
the 3-way fitting on the bottom of the assembly. Then, install the assembly to
the intake manifold (using a new gasket) and tighten the 2 nuts and 4
retaining bolts to 97 inch lbs.18 ft. Ibs. (11 Nm).
16. Install the Fuel Pump, as detailed later in this section.
17. Install the fuel filter and bracket assembly, and secure using the
retaining bolt.
18. Connect the throttle control rod to the throttle cam
19. For tiller models, connect choke rod to the lever on the bottom
carburetor, between the E-clips using the gaskets. Secure the outer E-clip to
hold the assembly in position.
20. Install and tighten the 2 bolts that secure the air silencer pipe to the
crankcase, then install and tighten the 2 bolts that secure the silencer case
to the powerhead.
21. Gently squeeze the primer bulb while checking for fuel leakage.
Correct any fuel leaks before returning the engine to service.
22. Install the starboard lower engine cover and secure using the 4
retaining bolts.
23. Install the flywheel cover and secure using the 3 retaining bolts or
install the manual starter assembly, as applicable.
24. Perform the necessary timing and synchronization procedures from
the Maintenance &Tune-up Section. If the carburetor was repaired or
rebuilt, be sure to perform the initial low speed adjustment procedure
Fig. 55 Stack of 3 carburetors found on 25/30 hp (3-cyl) motors
Carburetor
-
Fig. 56 Exploded view of the mounting for the 3 carburetors on
25/30 hp motors
Overhaul
CULT
See Figures 50,55 and 59
1. Position the carburetor over a small drain basin, then if equipped,
remove the float bowl drain screw from the carburetor float bowl and drain
any fuel remaining in the bowl.
On carbs which contain a covered pilot screw the manufacturer
warns NOT to remove the cover or attempt to adjust the screw. They do
-
not give an explanation for this (whetheror not this is IegalIEPA
related, but we have our suspicions).
2. Locate and remove the Pilot Jet from the bore in the upper side of
the carburetor body as well as the Main Air Jet and the Main Jet, each from
the bores at the front of the carburetor body (throttle bore).
Inlet
Case ^I
Carburetors
not pictured
Silencer
Gasket
\[r~arburetor Plate
Q
Fig. 57 Exploded view of the air silencer pipe and inlet case
assembly -25/30 hp (NOTE: carbs not shown)
3. If equipped and if desired, remove the low speed (idle mixture) screw
and spring from the bore in the side of the carburetor body. But before
removing the screw, count and record the number of turns required to turn in
and lightly seat the idle adjustment screw. The number of turns will give a
rough adjustment during installation. Then back out the idle speed screw and
spring from the side of the carburetor body.
On the bottom carburetor DON'T touch or remove the spring loaded
accelerator pump lever screw (the spring loaded screw on the same side
of carburetor body as the accelerator pump). This screw is preset at the
factory and should not require adjustment, UNLESS you disturb it.
4. Each carburetor will contain one or more spring loaded lever or
linkage screws. If desired, back each screw and spring out and position
aside. You may wish to take references, as to length of exposed threads or
depth that screw is seated to as reference during assembly and installation.
5. If working on the top carburetor and not done already, remove the
dash pot.
6. If working on the bottom carburetor, remove the accelerator pump
components. Start with the cap and boot, then unthread the holder. Remove
and discard the old O-ring from the holder. Remove the plunger and spring.
7. Invert the carburetor with the float bowl facing upward, then remove
the float bowl screws (usually 4). Slowly lift the float bowl and gasket from
the underside of the carburetor body exposing the float assembly. Remove
and discard the old float bowl gasket.
8. Remove the float hinge pin, then carefully remove the float and float
needle from the carburetor body. Loosen the screw securing the retainer,
then remove the inlet valve and O-ring.
9. Remove the main nozzle cap and O-ring, then remove the main
nozzle from the bore in the center of the carburetor body underside.
10. To check the electric choke on models so equipped, use a DVOM to
check solenoid coil resistance across the 2 terminals. At an ambient
temperature of about 68OF (20°C you should see about 3.8-4.2 ohms
resistance.
11. Thoroughly clean and visually check all of the carburetor components
as detailed under Cleaning & Inspection in this section.
To assemble:
12. Before starting, make sure all components are completely clean and
serviceable. Compare parts from the replacement kit (especially the gaskets)
to the parts removed from the carburetor. With the exception of wear or
damage that might occur on the old parts (requiring their replacement in the
first place) the new components should be identical. If you have any
questions, check with a local dealer to check parts against a current part
catalog before proceeding.
To ensure proper operation and durability, replace all displaced or
disturbed gaskets, O-rings or seals when rebuilding a carburetor
regardless of their appearance.
13. Install the main nozzle along with the nozzle cap and O-ring to the
bore in the center of the carburetor body underside.
14. Install the inlet valve using a new O-ring and secure with the
retaining plate and screw.
15. Carefully install the float along with the valve needle and secure
using the hinge pin. Turn the carburetor over for a second and check for
smooth float movement, then return the carburetor to the inverted position
with the float facing upward to measure installed float height.
16. Using a suitable vernier calipers or other instrument, measure the
distance from the float bowl gasket mating surface on the carburetor body to
the parallel surface on the bottom (now the top since it is upside-down) of
the float. This measurement should be 0.535-0.615 in. (13.6-15.6mm). If
adjustment is necessary carefully bend only the adjustment tab itself to
achieve the required measurement.
Be VERY careful when measuring or adjusting the float height not to
force the float needle valve downward into the seat. The valve or the
seat will likely be damaged if this occurs.
17. Install the float bowl to the carburetor body using a new gasket.
Install the cover screws, then securely using a crossing pattern.
18. For bottom carburetors (models with an accelerator pump), install the
pump plunger with the spring, then install the holder along with a new O-ring.
Install the boot and cop on the assembly. Actuate the pump plunger by hand
Fig. 58 Loosen the silencer case bolts, then the silencer pipe bolts 1 feeling for smooth operation of the pump plunger assembly.
Fig. 59 Exploded view of the carburetor assemblies used on 25/30 hp (3-Cyl) motors (NOTE: not all components used on each carburetor)
19. If applicable and if removed, install the low speed (piloffidle) mixture
screw and spring into the round boss on the side of the carburetor body.
Thread the screw slowly into the bore until it just lightly contacts the seat,
then back it off the specified number of turns you counted when you seated it
before unthreading during disassembly.
20. If removed, install the pilot jet, main air jet and main jet into their
respective bores in the carburetor body. The pilot jet goes in a bore on the
top side, while both main jets go in bores inlaround the throttle body, the
main AIR jet, higher up on the carburetor body than the main jet.
21. If the accelerator pump lever screw was disturbed, adjust the gap
between the accelerator pump lever and the pump plunger rod using the
adjusting screw. When properly set there should be no gap with the throttle
valve fully closed, but the rod should also not be preloaded significantly in
this position.
22. Install the carburetors, then perform the necessary timing and
synchronization procedures from the Maintenance & Tune-up Section
(including the idle speed and mixture adjustments).
CLEANING & INSPECTION
DERATE
See Figures 60 thru 65
Start by making sure that all components (even those being discarded)
are spread out on a clean work surface for inspection and comparison to
replacement parts. Make sure that gaskets are of the same patterns. If a
gasket differs, determine if the gasket will function by holding it to each side
of the gasket mating surface it will seal. Make sure that the replacement
doesn't block or cover any passage that the original did not. If it differs, seek
the advice of your parts supplier, they should be able to hunt down the
correct gasket or the reason it is now acceptable (possibly it's a superseding
part).
Some carburetors components used on these outboards are made of a
composite material. NEVER, EVER, EVER, submerge composite
components into a strong carburetor cleaner or a hot soaking tank.
Strong chemicals or hot tank may damage certain parts and sealing
compounds.
Never dip rubber parts, plastic parts, diaphragms, or pump plungers in
carburetor cleaner. These parts should be cleaned only in solvent safe for
plastic or rubber components and then immediately blown dry with low
pressure (less than 25 psi or 172 kPa) compressed air.
Always take precautions when working with solvent and compressed
air. Protect your eyes and your skin from chemical burns.
Place all metal parts in a screen-type tray and dip them in carburetor
cleaner until they appear completely clean, then blow them dry with
compressed air.
M If compressed air andlor a small solvent tank is not available, use a
commercially available carburetor and choke cleaner (such as that soid
by Suzuki) to clean components and blow out carburetor passages.
Blow out ail passages in the castings with low pressure compressed air
(less than 25 psi or 172 kPa). Whenever possible, apply air in the same
direction as normal air or fuel flow. Check all parts and passages to be sure
they are not clogged or contain any deposits. Never use a piece of wire or
any type of pointed instrument to clean drilled passages or calibrated holes
in a carburetor (wire could remove metal from the inner surface of a
calibrated passage, changing calibration from spec and causing performance
problems). If necessary, use something that is small, but softer than the
metal of the passages to clean them, like a piece of straw from a broom.
Fig. 60 Lay out all original parts for Fig. 61 Clean the carburetor body using
comparison to the rebuild kit spray Carburetor and Choke cleaner
Good Worn
Fig. 63 The float needle valve and seat must Fig. 64 Check all needle valves for grooves,
not be worn or deformed pitting or damage
If debris or contamination is found in the carburetor, inspect and
clean the entire system upstream of the carburetor. Chances are water
or debris contamination will be present in other components as well.
Failure to clean the entire fuel system could result in clogging a newly
rebuilt carburetor shortly after it is reinstalled.
inspect the main carburetor body, air horn or cover (if equipped) and float
bowl gasket sealing surfaces for nicks, gouges or irregularities, which could
cause a leak. Check ail nozzle and pickup tubes for security and cleanliness.
Inspect the tip of the needle valve for wear, distortion or damage. Replace
the needle valve and seat if damaged or worn. Good shop practice dictates
to always replace the needle valve and needle seat when the carburetor is
fully disassembled.
Move the throttle shaft back and forth to check for wear. If the shaft
appears to be too loose, replace the complete throttle body because
individual replacement parts are normally not available.
Check the float for deterioration. Check to be sure the float spring has not
been stretched. If any part of the float is damaged, the unit must be
replaced. Check the float arm needle contacting surface and replace the float
if this surface has a groove worn in it.
Inspect the tapered section of the idle adjusting needles and replace any
that have developed a groove.
Tightening a needle valve against the valve seat will result in damage
to the valve or seat and require replacement of damaged components.
Use great care when threading and seating the idle speed mixture
screw prior to backing it out for initial adjustment.
If the unit being serviced has an adjustable idle speed needle valve.
remove the needle valve (but not before gently turning it inward and counting
how many turns it was backed out at current adjustment). inspect the needle
valve tip for distortion or damage and replace the valve if damaged. Clean
the idle speed passages with spray carburetor cleaner and blow dry with
compressed air. During installation, screw the needle in until it just makes
Fig. 62 Pay close attention to any needle
tips during inspection
Fig. 65 Check the throttle shaft for
excessive wear (typical carb shown)
light contact with the seat. Now, back the needle out the appropriate number
of turns for the Initial Low Speed Setting (as detailed in the Carburetor Set-
Up Specifications chart in this section) or the same amount of turns it was
already backed out before removal.
As previously mentioned, most of the parts which should be replaced
during a carburetor overhaul are included in overhaul kits available from your
local marine dealer. One of these kits will contain a matched fuel inlet needle
and seat. This combination should be replaced each time the carburetor is
disassembled as a precaution against leakage (which could lead to flooding
during normal operation).
Before assembly, use a syringe filled with isopropyl alcohol to check all
drillings and passages.
See Figure 66
Carbureted models are equipped with a diaphragm-displacement type fuel
pump (actually, fuel injected models are too, at least for a lift-pump, but we'll
deal with them later in this section). The pump is mounted somewhere on
the side or end of the powerhead (powerhead crankcase or rockerlvalve
cover depending upon the model).
The pump is mounted in such a manner as to mechanically actuate the
diaphragm through a plunger that contacts a camshaft lobeldrive tang. For
most models this means the pump will actually be mounted on the valve
cover, putting it closest to the camshaft. However, on some models (like the
gear-driven camshaft of the 41516 hp and 25 hp V2 motors), locating it near
the camshaft actually means the pump is mounted to the side of the
powerhead.
Have a shop towel and a suitable container handy when testing or
servicing a fuel pump as fuel will likely spill from hoses disconnected
during these procedures. To ensure correct assembly and hose
routing, mark the orientation of the fuel pump and hoses before
removal.
1 Fig. 66 Typical Suzuki fuel pump 1
TESTING
See Figure 66
The problem most often seen with fuel pumps is fuel starvation, hesitation
or missing due to inadequate fuel pressure/delivery. In extreme cases, this
might lead to a no start condition as all but total failure of the pump prevents
fuel from reaching the carburetor(s). More likely, pump failures are not total,
and the motor will start and run fine at idle, only to miss, hesitate or stall at
speed when pump performance falls short of the greater demand for fuel at
high rpm.
Before replacing a suspect fuel pump, be absolutely certain the problem is
the pump and NOT with fuel tank, lines or filter. A plugged tank vent could
create vacuum in the tank that will overpower the pump's ability to create
vacuum and draw fuel through the lines. An obstructed line or fuel filter could
also keep fuel from reaching the pump. Any of these conditions could
partially restrict fuel flow, allowing the pump to deliver fuel, but at a lower
pressurelrate. A pump delivery or pressure test under these circumstances
would give a low reading that might be mistaken for a faulty pump. Before
testing the fuel pump, refer to the testing procedures found under Fuel Lines
and Fitting to ensure there are no problems with the tank, lines or filter.
If inadequate fuel delivery is suspected and no problems are found with
the tank, lines or filters, a conduct a quick-check to see how the pump
affects performance. Use the primer bulb to supplement fuel pump. This is
done by operating the motor under load and otherwise under normal
operating conditions to recreate the problem. Once the motor begins to
hesitate, stumble or stall, pump the primer bulb quickly and repeatedly while
listening for motor response. Pumping the bulb by hand like this will force
fuel through the lines to the carburetor, regardless of the fuel pump's ability
to deliver fuel. If the engine performance problem goes away while pumping
the bulb, and returns when you stop, there is a good chance you've isolated
the fuel pump as the culprit. Perform a pressure test to be certain, then
repair or replace the pump assembly.
.=
Never run a motor without cooling water. Use a test tank, a flush/test
device or launch the craft. Also, never run a motor at speed without
load, so for tests running over idle speed, make sure the motor is
either in a test tank with a test wheel or on a launched craft with the
normal propeller installed.
Pump Pressure Test
See Figure 66
By far the most accurate way to test the fuel pump is using a low pressure
fuel gauge while running the engine at various speeds, under load. To
prevent the possibility of severe engine damage from over-speed, the test
must be conducted under load, either in a test tank (with a proper test
propeller) or mounted on the boat with a suitable propeller.
H Unfortunately, Suzuki does not provide pump pressure
specifications for any of these motors. However, because fuel
consumption figures should be in the same ballpark for most motors of
similar sizelhp range we can at least use specifications from other
similar types of pumps found on other outboard brands as a starting
point. Therefore this test can be used to check for pressures that are
way out of the norm.
1. Test the Fuel Lines and Fittings as detailed in this section to be sure
there are no vacuurn/fuel leaks and no restrictions that could give a false low
reading.
2. Make sure the fuel filter(s) is(are) clean and serviceable.
3. Start and run the engine in forward gear, at idle, until normal
operating temperature is reached. Then shut the motor down to prepare for
the test.
4. Remove the fuel tank cap to make sure there is no pressure in the
tank (the fuel tank vent must also be clear to ensure there is no vacuum).
Check the tank location, for best results, make sure the tank is not mounted
any more than 30 in. (76mm) below the fuel pump mounting point. On
portable tanks, reposition them, as necessary to ensure accurate readings.
H The fuel outlet line from the fuel pump may be disconnected at
either the pump or the carburetor whichever provides easier access. If
you disconnect it from the pump itself you might have to provide a
length of fuel line (depending on whether or not the gauge contains a
length of line to connect to the pump fitting).
5. Disconnect the fuel output hose from the carburetor or fuel pump, as
desired.
6. Connect a fuel pressure gauge inline between the pump and the
carburetor(s).
7. Run the engine at or around each of the following speeds and
observe the pressure on the gauge.
8. Expect to find pressures in this ballpark:
0
At 600 rpm, the gauge should read about 1 psi (7 kPa).
0
At 2500-3000 rpm, the gauge should read about 1.5 psi (10 kPa).
At 4500 rpm, the gauge should read about 2.5 psi (17 kPa).
9. If readings are below specification and other causes such as fuel line
or filter restrictions have been eliminated, repair or replace the pump.
REMOVAL & INSTALLATION
See Figures 67 thru 70
1. For safety, either disconnect the negative battery cable (if so
equipped) and/or disconnect the spark plug lead(s) and ground them to the
powerhead.
2. On all except 4/56 hp motors, slowly and carefully turn the flywheel
(in the normal direction of rotation, Clockwise) to bring the No. 1 cyl up to
TDC as determined by the timing marks, this will help relieve pressure on the
fuel pump arm making it easier to install.
3. Locate the fuel pump on the powerhead and determine if access will
be easier if you first remove the lower engine covers. On some models
equipped with split (2-piece) lower covers, it is easier to access the pump if
the lower engine covers are removed (for instance on 9.9115 hp motors
access to the oumo is definitely blocked bv the covers). On most motors the
pump is located onlnear the valve cover, but there are'exceptions, like on [he
25 hp V2 motors where the pump is mounted to the base of tne crankcase
between the cylinder banks (which means at least the starboard lower
engine cover should be removed to ease access). For details, refer to the
Engine Cover procedure in the Engine Maintenance section.
On most motor the fuel hoses are retained spring-tensioned metal
clamps. To remove these clamps gently squeeze them with a pair of
pliers on the tabs and then slide the clamps up the hose, passed the
raised portion of the nipple.
4. On 25 hp V2 motors, release the fuel filter from the bracket to give
some extra play in the fuel hoses.
5. Place a small drain basin or a shop rag under the fuel line fittings (to
catch escaping fuel), then tag and disconnect the fuel hoses from the pump.
Although we say to tag the hoses, most Suzuki fuel pumps are labeled with
Fig. 67 If necessary, remove the lower Fig. 69 Fuel pump found on 9.9115 hp and
engine [email protected]) for access Fig. 68 Fuel pump found on 41516 hp motors larger motors
I516 H
1. Fuel Pump Body
2. O-ring or Gasket
3. Piston
4. Spring
Fia. 70 Various fuel uumw used on these Suzuki outboards
IN and OUT marks or arrows showing fuel flow, so even if you forget to tag
the lines you SHOULD be ok, but it's a good idea to check that first just to be
sure.
The fuel pumps used on these motors are normally equipped with 2
sets of bolts (though usually only one set is visible on the surface of
the pump). One set is used to hold the pump assembly together, and
on 9.9115 and laraer motors thev are usuallv threaded from behind the
pump body to confusion. The other set of bolts (normally just
two of them) are used to mount the pump to the powerhead. One easy
way to identify them is that they areusually threaded through the
lowest and widest portion of the pump body and not the pump cover
itself. Refer to the accompanying illustrations to help identify the
correct bolts.
6. Loosen the oumo mountina bolts (the bolts that thread not throuah
the inlet cover, but the body of thepump and into the powerhead) identify the
correct bolts depending upon model and pump type, as follows:
* 41516 hp models utilize a square-bodied pump with 4 visible cover
screws mounted to a pump rounded diamond-shaped pump base secured
with 2 larger pump mounting bolts. The 2 mounting bolts should be easy to
identify since they are not threaded through the square pump body.
9.9 hp and larger models use a pump that has a round cover on a
rounded diamond-shaped body. These are easy to figure out the correct
9.9 HP and larger
5. Cover Screw
6. Mounting Screw
7. Diaphragm
screws as there are normally only 2 mounting screws exposed when the
pump is installed (one at either end of the rounded diamond-shaped body).
The 6 cover screws that hold the assembly together on most models are
installed from the underside of the diamond-shaped body.
If in doubt as to which bolts secure the pump, look at the back of
the pump (as can be seen at the pump-to-powerhead seam line) to see
which bolts continue throuah the uumu assembly and into the
powerhead. These are the only bolts that shouldbe loosened for pump
removal.
7. Once the mounting screws are out, carefully remove the pump from
the powerhead.
8. If necessary, remove the cover screws andlor body screws in order
to disassemble the fuel pump for inspection or overhaul, as applicable. For
details. refer to the Fuel Puma Overhaul orocedure in this section.
9. Clean the mating surface of the and powerhead. Be careful not
to damage the surface as that could lead to oil leaks. Most pumps are
seated with an O-ring, be sure to replace that O-ring each time the pump is
removed to ensure proper sealing.
To install:
10. On all except 41516 hp motors, if the powerhead was serviced or the
flywheel rotated while the pump was off, slowly and carefully turn the
flywheel (in the normal direction of rotation, Clockwise) to bring the No. 1 cyl
up to TDC as determined by the timing marks, this will help relieve pressure
on the fuel pump arm making it easier to install.
11. Apply a light coating of Suzuki water resistant grease, an equivalent
marine grade grease, or some engine oil to the new pump O-ring.
12. Position a new O-ring and install the pump to the powerhead using
the retaining screws. Tighten the screws to specification as follows:
41516 hp motors: 72 inch lbs.16 ft. Ibs. (8 Nm)
9.9 hp and larger: 89 inch 1bs.R ft. Ibs. (10 Nm)
13. Reconnect the fuel lines as noted during removal and secure using
the clamp or new wire ties, as applicable. When reusing spring clamp, make
sure they are still in good condition and haven't lost their spring, if in doubt,
replace them.
14. Gently squeeze the primer bulb while checking for fuel leakage.
Correct any fuel leaks before returning the engine to service.
15. If removed, install the lower engine covers.
16. Connect the negative battery cable andlor spark plug lead(s).
OVERHAUL
@ See Figure 70
Most of the fuel pumps used on these motors may be disassembled for
overhaul. And, happily, the pumps are of a fairly simple design with relatively
few moving parts. But before taking one apart, check with your local parts
supplier to make sure that an overhaul kit containing the necessary parts are
available for your model. In most cases, the parts are limited to the
diaphragm(s), gasket(s) and a fuel inlet screen (if equipped), though some
might include the check valve components as well.
Though it appears the 25 hp V2 motor uses the same basic design
pump as the other 9.9 hp and larger motors, some factory service
information states that it is NOT SERVICEABLE and should not be
disassembled.
If overhaul is required due to damage from contamination or debris (as
opposed to simple deterioration over time) disassemble and clean the rest of
the fuel supply system prior to the fuel pump. Failure to replace filters and
clean or replace the lines and fuel tank, could result in damage to the
overhauled pump after it is placed back into service.
All diaphragms and seals should be replaced during assembly, regardless
of their condition. Check for fuel leakage after completing the repair and
verify proper operating pressures before returning the motor to service.
No sealant should be used on fuel pump components unless otherwise
specifically directed. If small amounts of a dried sealant were to break
free and travel through the fuel supply system it could easily clog
passages (especially the small, metered orifices and needle valves of
the carburetor).
1. Remove the fuel pump from the powerhead as detailed in this
section.
2. Matchmark the fuel pump cover, housing and base to ensure proper
assembly.
B To ease inspection and assembly, lay out each piece of the fuel
pump as it is removed. In this way, keep track of each component's
orientation in relation to the entire assembly.
3. On 41516 hp motors, proceed as follows:
a. Remove the 4 pump cover screws (they are threaded through nuts
on the under side of the body so you'll have to keep the nuts from turning),
then separate and carefully remove the pump cover, outer diaphragm and
the square pump valve body.
b. Locate the pump plunger (piston at the backside of the diamond-
shaped pump body) for the diaphragm assembly, then gently pivot it
counterclockwise until if you align the piston pin with the hole in the side of
the pump body. Remove the pin, freeing the piston and inner diaphragm
assembly.
When removing the piston pin, keep gentle pressure on the piston
and diaohraam components as springs mounted under each will
attemptto push them outward. ~on'tloose the springs or allow
components which may be reused to become damaged.
c. Remove the piston and smaller diameter spring from underneath the
pump body. Remove the diaphragm and larger diameter spring from the top
side of the pump body.
4 On 9.9 hp and larger motors with a serviceable pump, disassemble
the pump as follows:
a. Invert the pump so it is sitting on the cover with the plunger facing
upward. Remove the 6 cover screws from this backside of the pump. Then
remove the round pump cover, outer diaphragmlgasket and the round valve
body.
b. Next move to the underside of the pump assembly again. Rotate the
piston (on one side) and the diaphragmlplunger (on the other side) until the
pin comes out through the cutout in the pump body. While placing gentle
pressure on the diaphragm (on top) and piston (on the bottom) to hold the
components against spring pressure, remove the pin, then carefully remove
the retaining components. On the underside remove the piston and the
smaller diameter spring. On the topside remove the diaphragmlplunger and
the larger diameter spring.
On all models now:
5. Clean the metallic components thoroughly using solvent and carefully
remove all traces of gasket material.
6. Inspect the diaphragm closely for cracks or tears.
B It is advisable to replace the diaphragm ANYTIME the fuel pump is
disassembled to ensure reliability and proper performance. As a matter
of fact, for most models the manufacturer specifically states NOT to
attempt to reuse a diaphragm set. Once the set is removed it is highly
unlikely that it will ever be aligned properly and seal properly again.
7. Inspect the fuel pump body for cracks. Check gasket surfaces for
nicks, scratches, or irregularities. Inspect the mating surfaces of the fuel
cover, body and base using a straight edge to ensure that they are not
warped from heat or other damage Replace warped or damaged
components.
8. Check the springs for damage or lack of tension.
To assemble:
9. Assemble the components of the fuel pump housing, base and
diaphragm noting the following:
a. Use new 0-ringlgaskets and diaphragms. Make sure each gasket
and the components it seals are aligned properly.
b. Align the matchmarks made during disassembly to ensure proper
component mounting.
c. Insert the piston pin then rotate the diaphragm about 90' to make
sure the piston pin cannot come out of the slot in the pump body.
10. Apply a coating of Suzuki Nut Lock, or an equivalent threadlocking
compound to the pump housing and base screws, then install and tighten
them securely to 35-56 inch Ibs. (4-6 Nm).
11. If equipped, install the fuel pump cover and filter screen using a new
gasket or O-ring($ then tighten the center screw securely.
12. Install the fuel pump, then check for leaks and for proper operation.
@ See Figure 71
Cold start enrichment is achieved through various means on the different
carbureted Suzuki motors covered here. The means include a manual or
electric choke plate and a manual or electric primer.
Generally speaking, all but the late-model (Keihin carburetor equipped)
9.9115 hp and 25 hp V2 motors utilize a manual or electric choke, while the
Keihin carburetors found on 9.9115 hp and 25 hp V2 motors utilize a manual
or electric primer.
Whether or not the choke or primer is electrically actuated or not is simply
dependent upon trim, rope start, tiller control, remote electric etc, but
regardless of how it was spec'd to come from the factory it could have been
changed on rigging. At the end of the day it's simple. If you've got a choke
knob and linkage or cable that goes to the carburetor, it's manual. If you've
got some wires going to a component mounted to the carburetor and no said
linkagelcable, then it's electric.
For more details on model-by-model basis, please refer to the General
Engine System Specifications chart in the Maintenance & Tune-up section.
Now you might be asking, what is the difference between a choke and a
primer? Essentially they both achieve the same result (a richer air!fuel ratio
to help a cold engine start and run), but through the exact opposite means.
Achoke does exactly what it sounds like, it physically blocks off some of
the air to the carburetor so that the same amount of fuel that is normally
metered into the intake manifold is now of greater ratio because there is less
air.
In contrast, an enrichener does not restrict the air flow, but instead opens
up a secondary fuel metering passage. In this way more fuel is introduced
for the same amount of air, again, making the ratio more rich.
As far as primers are concerned, there is only one manual type found on
these motors. On Keihin-equipped 9.9115 hp and 25 hp V2 motors a simple
cable and plunger assembly is mounted to the top of the carburetor. When
the starter knob is pulled on this style primer additional fuel is drawn into the
starter circuit from the carburetors float bowl. The starter jet meters this fuel,
which then flows into the fuel pipe to mix with incoming air from the upper
part of the float chamber. This rich fuel mixture then reaches the starter
plunger and mixes again with air coming from a passage from the main bore.
Remixing the incoming air in such a manner produces a suitably rich fuel
mixture for starting when it is sprayed through the starter outlet port into the
main bore. Service on this system is limited to replacement of the
cablelplunger assembly or servicing the carburetor passages themselves.
For more details on servicina these models, olease refer to the amrotxiate
. .
Carburetor Overhaul procedure earlier in this section.
The electric primer found on some 9.911 5 hp and 25 hp V2 models
equipped with a Keihin carburetor functions in the same fashion as the
manual primer, the only difference being that it is electronically actuated. Like
the manual primer version of these motors the electric primer is attached to
the top of the carburetor body and works with internal carburetor passages
and the fuel supply already in the carburetor float bowl. Also similar to the
manual primer system service is limited to removal from the carburetor and
replacement of the entire auto-enrichener valve assembly. The assembly
consists of a PTC heater, a thermo-wax and a plunger needle. When the
wax is cold the plunger needle is held in an upward position allowing fuel to
be drawn from the float bowl into the enrichener circuit. The wax will expand
when hot (either from sufficient ambienffengine temperature or when the
PTC heater coil has warmed it) pushing the needle into the enrichener
passage, closing it off.
TESTING
See Figure 71
An inoperable chokelprimer will cause hard start or possibly even a no
start condition during attempts to start a cold motor. The colder the ambient
temperature, the more trouble an inoperable chokelprimer will cause. A
primer (manual or electric) with internal leakage (allowing fuel to bypass the
airlfuel metering system) will cause rich running conditions that could include
hesitation, stumbling, rough running, especially at idle and lead spark plug
fouling.
When it comes to chokes, the most simply test is to visually check that
the choke linkage andlor the choke plate (you'd have to remove the air
intake silencer and peer down the throttle body for that later one) is actually
moving (openinglclosing) when the choke is actuated (electrically or
mechanically, as applicable).
There are a few additional tests by function or for the electronic
components of electric chokelprimer system.
Function Test
This test should work for manual chokes and primers. It may work for
electric chokes if the circuit is set-up in such a wav that it can be
electronically engaged, on even a hot engine, butthe design of the electric
primer (using a heating element) will normally prevent it from being effective
on those motors).
If the motor is operable, but trouble is suspected with the chokelprimer
system, perform a function test with the engine running. Although this test
can be conducted on a flush-fitting, engine speed will reach 2000 rpm and it
is much safer to conduct the test in a test tank or with the boat launched.
1. Start and run the engine until it reaches normal operating
temperature.
2. Once the engine warms, set the throttle so it runs at 2000 rpm.
3. Activate the chokelprimer and observe engine operation. If the
chokelprimer is operating correctly, the engine should run rich and should
hesitatelstumble, speed should drop to about 1000 rpm.
Electric Primer or Choke Testing
To check the electric choke on 9.9115 hp motors equipped with Mikuni
carburetors, use a DVOM to check solenoid coil resistance across the
terminals for the Orange and Black wires. At an ambient temperature of
about 68'F (20°C you should see about 2.8-4.2 ohms resistance.
To check the electric choke on 25/30 hp (3-cyl) motors equipped with
Mikuni carburetors, use a DVOM to check solenoid coil resistance across the
2 terminals. At an ambient temperature of about 68'F (20°C you should see
about 3.8-4.2 ohms resistance.
To check the electric primer on 9.9115 hp and 25 hp V2 motors equipped
with Keihin carburetors, only the most simple testing is possible or necessary
for this system. By removing the enrichener, noting the position of the needle
and then hooking it up to 12-volts and waiting for at least 5 minutes you can
I if the system is working. The needle must be visibly longer after 5
minutes or the assembly must be replaced.
Disconnect the negative battery cable ANYTIME work is performed on
the engine, especially when working on the fuel system. This will help
prevent the possibility of sparks during service (from accidentally
grounding a hot lead or powered component). Sparks could ignite
vapors or exposed fuel. Disconnecting the cable on EFI motors will
also help prevent the possibility fuel spillage (ok, fuel SPRAY) if the key
is turned to start while the high-pressure fuel system is open.
Fuel leaking from a loose, damaged or incorrectly installed hose or
fitting may cause a fire or an explosion. ALWAYS pressurize the fuel
system and run the motor while inspecting for leaks after servicing any
component of the fuel system.
nla: not applicable
Initial low speed setting turn(@: back (counterclockwise) from a lightly seated position
@ No published specification. We recommend you lightly seat the needle, counting the number of turns it takes, before removal and reuse that setting.
@ These carbs are preset to this specification and sealed
6 See Figures 72 thru 80
The fuel system used on all 40 hp and larger models is an electronically
controlled multi-port fuel injection system, not unlike that used on modern
automobiles. If fact, all of the EFI motors covered here are built by Suzuki for
Suzuki and, the 60170 hp motor is essentially a marinized and updated
version of the motor found in the Suzuki Sidekick and Geo Tracker for many
years.
The EFI system itself can be segmented into 3 inter-related sub-systems:
Q
Low pressure fuel circuit
*
High pressure fuel circuit
*
Electronic engine controls
The low pressure circuit delivers fuel from the tank to the vapor separator
via a mechanical diaphragm-displacement fuel pump, very similar in form
and function to those used on mid-range Suzuki carbureted motors. The low
pressure circuit may be rigged with a portable or built-in fuel tank and
normally contains both an inline filter and a fuel primer bulb. The role of the
low pressure circuit is to keep the high pressure circuit electric pump
supplied with sufficient fuel to meet engine operating demands.
The high pressure circuit is necessary to ensure proper operation of the
fuel injectors (whose operation depends upon a constant supply of highly
pressurized fuel). The circuit uses a high pressure pump mounted within the
vapor separator tank to build system pressure and maintain it through a fuel
pressure regulator that vents excess fuellpressure back into the vapor
separator tank. Fuel injectors, mounted between a fuel rail assembly and the
intake manifold or cylinder head, deliver the high pressure fuel directly before
the cylinder head mounted intake valves for each cylinder. The high pressure
circuit is activated by the engine's Electronic Control Module (ECM) for a few
seconds every time the ignition is turned ON and constantly during engine
cranking or operation. Fuel injectors, also controlled by the ECM, are
electronic solenoid valves that open against internal spring pressure when
activated (allowing fuel to spray from the nozzle tips), injector activation
occurs sequentially, immediately before each intake valve is ready to open.
The electronic engine control system monitors and controls engine
operation in order to properly meter fuel delivery to match operating
conditions. The role of the ECM and the fuel injectors is to do electronically
what the carburetor does mechanically on other motors. The precise control
made possible by the ECM's microprocessors allows an EFI engine to
increase both reliability and performance while simultaneously decreasing
harmful emissions. And, those are ail good things, right?
The electronic engine control system monitors engine operation through a
number of electronic switches and sensors. The role of the sensors and
switches is to translate mechanical information such as engine temperature,
powerhead speed, throttle position or even the exact position of the pistons
(on what portion of each stroke, each piston is) into electronic data for use
by the ECM. The system is equipped with the following sensors:
* Camshaft Position (CMP) sensor (including additional CMPs on
Variable Valve TimingIVVT models such as the 175 hp, 250 hp and 300 hp
models)
Crankshaft Position (CKP) sensor
0
Closed Throttle Position (CTP) switch (except 150 hp and larger
models)
*
Cylinder Temperature (CT) sensor
Q
Intake Air Temperature (IAT) sensor
Q
Exhaust Manifold (EM) temp (multiple ones on V6 models)
*
Manifold Air Pressure (MAP) sensor
Shift Position (SP) sensor (150 hp and larger models)
Q
Throttle Position Sensor (TPS) (150 hp and larger models, multiple -
both a main and sub for 300 hp models)
4
Water Pressure (WP) sensor (300 hp models)
Q
Tilt and Trim Sensor (300 hp models)
In addition, the ECM will also use signals from various switches, including
the Neutral switch, Oil pressure switch, Emergency stop switch and Ignition
switch.
In fuel injection terms this type of system is known as a speed-density
injection system. This is because the basic engine fuel mapping decisions
are made by the ECM based on a comparison between the engine rpm
(speed) and the manifold pressure (air density). The basic, pre-programmed,
fuel mapping is then modified based upon input from the remaining sensors.
Specifically, cylinder and air temperatures are taken into account. When a
CTP switch or TPS sensor (as equipped) signal is received (showing that the
throttle is closed), the ECM uses a fuel delivery strategy specifically intended
for idlingltrolling.
Besides the amount of fuel delivered (controlled through the fuel injectors)
the ECM can also control the amount of air delivered during idle conditions.
This is accomplished through the Idle Air Control (IAC) valve.
The ECM uses inputs from the CMP sensor(s) to control the fully
electronic ignition system and make all ignition timing adjustments.
To make matters even MORE complicated, the 300 hp motors uses an
electronic throttle (fly-by-wire) system which means there is a second
computer involved, the Boat Control Module (BCM) on these motors. The
BCM interfaces with the ECM through CAN Communication System and
Controller Area Network. Like the BCM (just like the ECM) receives various
inputs (such as from the Main Switch, the Lever Position Sensor or Sensors,
the Start and Stop Switch or Switches, etc) and gives various output signals
to the ECM to control the Throttle Motor Relay and the Shift Motor Relay.
The BCM also has the ability to receive inputs from the ECM such as when
to control the warning buzzer (of which the BCM maintains direct control).
On carbureted outboards fuel is metered through needles and valves that
react to changes in engine vacuum as the amount of air drawn into the motor
increases or decreases. The amount of air drawn into carbureted motors is
controlled through throttle plates that effectively increase or decrease the
size of the carburetor throat (as they are rotated open or closed).
In contrast, while fuel injected engines still use a throttle plate or plates to
regulate the amount of air allowed in the motor, they also use a computer
control module to regulate the amount of fuel introduced to the motor (to
match that fuel to the amount of air). The module or Electronic Control
Module (ECM) monitors input from various engine sensors in order to
receive precise data on items like engine position (where each piston is on
its 4-stroke cycle), engine speed, engine and air temperatures, manifold
pressure and throttle position. Analyzing the data from these sensors tells
the engine exactly how much air is drawn into the motor at any given
moment and allows the ECM to determine how much fuel is required.
The ECM will energize (open) the fuel injectors for the precise length of
time required to spray the amount of fuel needed for that intake stroke. In
actuality, the injectors are not just activated and held-open as much as they
are pulsed, opened and closed rapidly for the correct total amount of time
necessary to spray the total desired amount of fuel. This electronically
controlled, precisely metered fuel spray or "fuel injection" is the heart of a
modern EFI system and the main difference between an injected and
carbureted motor.
Troubleshooting a fuel injected motor contains similarities to carbureted
motors. Mechanically, the powerhead of a 4-stroke fuel injected motor
operates in the same way as that of a 4-stroke carbureted motor. There still
must be good engine compression and mechanical timing (valves must open
and close fully and at the right time) for either engine to operate properly.
Wear or physical damage will have virtually the same affect upon either
motor. Furthermore, the low pressure fuel system that supplies fuel to the
reservoir in the vapor separator tank operates in the same manner as the
fuel circuit that supplies gasoline to the carburetor float bowl.
INPUT (sensor/switch) OUTPUT (actuator etc.)
I
Fuel injection control system Fuel injector 1
we[
Ignition coil
1 MAP sensor Idle air control system IAC valve I
I IAT s e n s o r Fuel pump control system 1 High pressure fuel pump
1 Cylinder temp. sensor 1 Caution buzzer I
Fail-safe system
CTP switch
1 JI I
Start-in-gear protection system Starter motor
J
Neutral switch
O2 feedback system
1 Oil oressure switch
O2 sensor (optional)
Fig. 72 Fuel injection control system inputs and outputs -40-140 hp motors
Fuel tank
Low pressure
fuel filter
ntrol
Ignition
switch
1 1
Alternator
(Battery charge coil) Rectifier regulator
OzSensor must be installed when performing "Osfeedback operation" only
Fig. 73 Fuel injection system schematic -40150 shown, but 60-140 hp motors VERY similar
INPUT CONTROL OUTPUT
(eenaor/swlfch) (actuator etc.)
-Fuel InJector
CMP sensor È Ignition coil
CMP sensor È Oil control valve
MAP sensor
High pressure fuel pump
IAT sensor
Cylinder temp. sensor VSV (Vacuum switching valve)
Exhaust manifold temp. sensor
Throttle position sensor 1---+1
Caulion system
1 sen diagnostic system
Caution Buzzer ^Ñ
Neutral switch
Shift position sonsor
Fall safe system I
Oil pressure switch
Emergency stop switch
Starter motor relay,
(Starter motor)
02 sensor (Optional)
NOTE:
* DF150 model is not equipped with CMP sensor #2and VW system.
Fig. 74 Fuel injection control system inputs and outputs -1501175 hp motors
CKP sensor
Ignition coil
Fuse
: Os Sensor must be installed when oerformino
"02feedback operation" only.
": DF150 model is not equipped with OCV and VW system.
Fla. 75 Fuel injection system schematic -1501175 hp motors
/
/
Throttle position sensor
I
MAP sensor
INPUT OUTPUT
(sensor/switch) (actuator etc.)
CKP sensor
Fuel injection system -Fuel injector
Ignition coil
-IAC valve
-
-
-
-
-OCV (Oil control valve)
MAP sensor
-rLow pressure fuel pump
Fuel pump system
tAT sensor High pressure fuel pump
CMP sensor #3(250 HP)
WT system
^=^1
1 Cylinder temp. sensor
-VSV (Vacuum switching valve)
Evaporation purge system I Purge valve
Caution system Caution Buzzer
Exhausl manifold lamp. sensor #2
i
Throttle position sensor -
Seif-diagnostic system
Neutral switch -Monitor-tachometer
Shift position sensor -
Oil pressure switch -
Starter motor relay,
Ignition switch (Starter motor)
Starter motor relay control system
1 Oa sensor 1Ootionatl
1-
Oafeedback system
I
IMPORTANT: 200 and 225 HP models are not equipped with CMP sensor #2 and 3 or WT system
200 HP model is not equipped with Multi-stage induction system.
ECM
I A 1
Fuse
: Ch Sensor must be installed when periorming
"02 feedback operation" only.
Throttle position sensor' MAP sensor
Fig. 77 Fuel injection system schematic -200 hp motors
sensor I
Emergency
stop switch
Main relay P1 I
Fuse
:O? Sensor must be installed when performing
Throttle position sensor' "Oa feedback operation" only.
":DF225model is not equipped with OCV and WT system
Fig. 78 Fuel injection system schematic -2251250 hp motors
MAPsensor
INPUT
(sensor/switch)
CMP sensor ft2
CMP sensor È
MAP sensor
IAT sensor PI
Main switch
CKP sensor
1 Ignition system
1 Fuel wmo wstam
t
I
1ignition coil
4011control valve 1
OUTPUT
(actuator etc.)
PWIURI pump system 1
High pressure fuel pump system
Cylinder temp. sensor Evaporation purge system
I
-1
~ u valve
m
I
Exhaust manilold tamp. esneor #1
Exhaust manifold temp. snwr a2
Throttle motor relay
Throttlepositionsewr (Main.Sub) 1 Electronic lhrottle system
I
Throttle motor Neutral switch
Shift position sensor
OH pressure switch
Emergency stop switch Caution system
Tachometer-monlinrWater pressure sensor Sail diagnostic system
Digital display screen
Speed sensor Fallsafe system
Tilt &Trim sensor 1 .ChxraUno hour indtat$onsvmm 1
1
Oil chan&a reminder sys&m f
Start-in-gear protection system prter motor m!q (Starter motor) 1
.Station select switch
Throttle only switch
Starter motff relay control system
-STAFIT& STOP willch
r*l BCM
1 I
CAM Controler Acea Network
BCM
Fig. 79 Fuel injection control system (Engine Control Module) inputs and outputs -300 hp motors
INPUT CONTROL OUTPUT
(sensor/swltch etc.) (BCM) (actuator etc.)
Main switch
BCM power source Throttle motor relay
1
Lever position sansor 1 (Main. Sub) CAN Communication system
ÑÑÃ
' I^^^
Lever position sensor 2 (Mein. Sub) ^I
I I
Caution buzzer
I
START 8.STOP switch 2
START & STOP switch 3
1
b--+
Emergency stop switch
1 ThmtSie onlv switch b
Station select switch
Digital display screen
-Enoine RPM
1 Synchronization switch
.Engine temperature .Battery voltage .Fuel consumption
Engine operation hours
a Shift position .Oil change reminder .SeWiagnostic code
*Caution display
a Trim angle
-Coolina water oressure
Fig. 80 Fuel injection control system (Boat Control Module) inputs and outputs -300 hp motors
-1
The major difference in troubleshooting engine performance on EFI
motors is the presence of the ECM and electronic engine controls. The
complex interrelation of the sensors used to monitor engine operation and
the ECM used to control both the fuel injection and ignition systems makes
logical troubleshooting all that nr.uch more important.
Before beginning troubleshooting on an EFI motor, make sure the basics
are all true. Make sure the engine mechanically has good compression (refer
to the Compression Check procedure that is a part of a regular Tune-up).
Make sure the fuel is not stale (perhaps substitute a portable fuel tank with
known good fuel to eliminate that possible cause of a problem). Check for
leaks or restrictions in the Lines and Fittings of the low pressure fuel circuit,
as directed in this section under Fuel Tank and Lines. EFI systems cannot
operate properly unless the circuits are complete and a sufficient voltage is
available from the battery and charging systems. A quick-check of the battery
state or charge and alternator output with the engine running will help
determine if these conditions are adversely affecting EFI operation.
Loose/corroded connections or problems with the wiring harness
cause a large percentage of the problems with EFI systems. Before
getting too far into engine diagnostics, check each connector to make
sure they are clean and tight. Visually inspect the wiring harness for
visible breaks in the insulation, burn spots or other obvious damage.
In order to help find electronic problems with the EFI system, the ECM
contains a self-diagnostic system that constantly monitors and compares
each of the signals from the various sensors. Should a value received by the
ECM from one or more sensors fall outside certain predetermined ranges
the ECM will determine there is a problem with that sensor's circuit.
Basically the ECM compares signals received from different sensors to each
other and to real world possible values and makes a decision if it thinks one
must be lying. For instance, if the ECM receives camshaft position sensor
signals that show the engine is rotating, but also receives a signal from the
crankshaft position sensor that says the engine is stopped, it knows one is
wrong (presumably the one that says it's stopped because of the way the
know there is something wrong with that signal. Depending on the severity of
the fault or faults, the engine will likely continue to run, substituting fixed
values for the sensors that are considered out of range. Under these
circumstances, engine performance and economy may become drastically
reduced.
H Record diagnostic codes as described in this section BEFORE
disconnecting the battery. If codes are not present, yet problems
persist, use the symptom charts (toward the end of the diagnostic
charts for each motor) to help determine what further components or
systems to check.
When a fault is present the ECM will store a diagnostic code in memory.
The ECM will illuminate the Check Engine light in the gauge package and
sound the warning horn to alert the operator. Codes can be read from the
flashing of the Check Engine light and then used to help determine what
components and circuits should be checked for trouble. Remember that a
fault code doesn't automatically mean that a component (such as a sensor)
is bad, it means that the signal received from the sensor circuit is missing or
out of range. This can be caused by loose or corroded connections,
problems with the wiring harness, problems with mechanical components
(that are actually causing this condition to be true), or a faulty sensor.
B An important diagnostic procedure for electronic engine controls
which is known by some as the "Wiggle Test" involves cranking or
operating the motor while you physically grab and shake parts of the
wiring harness. If the symptoms occur when doing this you have likely
found intermittently loose connections or wires which may be broken
underneath the insulation. Further testing on those specific wires may
indeed confirm your suspicion.
In addition, when possible, troubleshooting charts are provided based on
certain trouble codes or symptoms that should be used to help narrow down
problems in engine performance. Refer to these charts (after performing the
sensors function!. Similarly, if it receives a ridiculous sianal, sav the intake an basic checks mentioned earlier) to help determine what further components
temperature suddenly a signal above 338OF (i7ooc),the ECM will or systems to check.
Once components or circuits that require testing have been identified, use
the testing procedures found in this section (or other sections, as applicable)
and the wiring diagrams to test components and circuits until the fault has
been determined.
Keep in mind that although a haphazard approach might find the cause of
problems, only a systematic approach will prevent wasted time and the
possibility of unnecessary component replacement. In some cases, installing
an electronic component into a faulty circuit that damaged or destroyed the
previous component, will instantly destroy the replacement. For various
reasons, including this possibility, most parts suppliers do not accept returns
on electrical components.
DEBATE
See Figures 81,82 and Charts 1 thru 9
READING & CLEARING CODES
DERATE
See Figures 81,82 and Charts 1 thr
Certain electrical equipment such as stereos and communication
radios can Interfere with the electronic fuel injection system. To be
certain there is no interference, shut these devices off when
troubleshooting. If a check engine light illuminates immediately after
installing or re-rigging an existing accessory, reroute the accessory
wiring to prevent interference.
When the electronic engine control system detects a problem with one of
its circuits, the ECM will activate the check engine light found in the gauge
pack (usually the gauge built into the tachometer on these models) and in
most cases will sound the warning horn. As a result of most faults, the ECM
will ignore the circuit signal and enter a fail-safe mode designed to keep the
boat and motor from becoming stranded. During fail-safe operation the ECM
I provide a fixed substitute value for the faulty circuit. During fail-safe
operation the engine will run, but usually with reduced performance (power
and economy). Substitute values are generally as follows:
5
MAP sensor: 319-475mm Hg @ 750-4000 ipm for 40-140 hp motors
or, 260-760mm Hg for 15011 75 hp motors or 280-560mm Hg for V6 motors,
the later two groups also under varying engine speeds for (but no specific
range is given though one would assume it was probably about 750-6000
rp6dep