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Contents1 GENERAL INFORMATION AND BOATING SAFETY 2 TOOLS AND EQUIPMENT 3 MAINTENANCE 4 FUEL SYSTEM 1-2 HOW TO USE THIS MANUAL1-3 BOATING SAFETY 1-1 0 SAFETY IN SERVICE 2-2 TOOLS AND EQUIPMENT 2-11 FASTENERS,2-4 TOOLS MEASUREMENTS AND CONVERSIONS3-2 ENGINE MAINTENANCE 3-38 WINTER STORAGE 3-8 BOAT MAINTENANCE CHECKUST 3-10 TUNE-UP 3-39 SPRING COMMISSIONING CHECKLIST 4-2 FUEL AND COMBUSTION 4-50 ELECTRONIC FUEL 4-3 CARBURETED FUEL INJECTION (ER) SYSTEM 4-66 OPTIMAX DIRECT FUEL INJECTION (DFI) 5-2 UNDERSTANDING AND 5-30 CHARGING CIRCUIT TROUBLESHOOTING 5-40 STARTER CIRCUIT ELECTRICAL SYSTEMS 5-8 BREAKER POINTS 5-42 IGNITION AND IGNITION (MAGNETO ELECTRICAL WIRING IGNITION) DIAGRAMS 5-14 CAPACITOR DISCHARGE IGNITION (COl) SYSTEM 6-2 OIL INJECTION SYSTEM 6-27 OPTIMAX WARNING 6-8 COOLING SYSTEM SYSTEMS 6-22 WARNING SYSTEMS 7-2 ENGINE MECHANICAL 8-2 9-29-59-6 LOWER UNIT MANUAL TILT GAS ASSIST TILT SYSTEM POWER TRIM/TILT 7-19 POWER HEAD RECONDITIONING 8-11 JET DRIVE 9-7 SINGLE RAM INTEGRAL POWER TILT/TRIM 9-12 THREE RAM INTEGRAL POWER TILT!TRIM SYSTEM 10-2 REMOTE CONTROL BOX 10-6 TILLER HANDLE 11-2 HAND REWIND STARTER 11-2 OVERHEAD TYPE STARTER 11-25 GLOSSARY 11-27 INDEX Contents POWERHEAD 7 LOWER UNIT 8 TRIM AND TILT 9 REMOTE CONTROL 10 HAND REWIND STARTER 11 GLOSSARY MASTER INDEX See last page lor information on additional titles TOOLS AND EQUIPMENT 2-2 SAFETY TOOLS 2-2 WORK GLOVES 2-2 EYE & EAR PROTECTION 2-2 WORK CLOTHES 2-2 CHEMICALS 2-2 LUBRICANTS & PENETRANTS 2-2 SEALANTS 2-3 CLEANERS 2-3 TOOLS 2-4 HAND TOOLS 2-4 SOCKET SETS 2-4 WRENCHES 2-6 PLIERS 2-7 SCREWDRIVERS 2-7 HAMMERS 2-7 OTHER COMMON [email protected] 2-7 SPECIAL TOOLS 2-8 ELECTRONIC TOOLS 2-8 GAUGES 2-9 MEASURING TOOLS 2-9 MICROMETERS & CALIPERS 2-9 DIAL INDICATORS 2-10 TELESCOPING GAUGES 2-10 DEPTH GAUGES 2-10 FASTENERS, MEASUREMENTS AND CONVERSIONS 2-11 BOLTS, NUTS AND OTHER THREADED RETAINERS 2-11 TORQUE 2-11 STANDARD AND METRIC MEASUREMENTS 2-11 SPECIFICATIONS CHARTS CONVERSION FACTORS 2-12 ..... 2-2 TOOLS AND EQUIPMENT TOOLS AND EQUIPMENT Safety Tools WORK GLOVES • See Figures 1 and 2 Unless you think scars on your hands are coot, enjoy pain and like wearing bandages. get a good pair ot work gloves. Canvas or leather are the best. And yes, we realize that there are some jobs involving small parts thai can't be done while wearing work gloves. These jobs are not the ones usually associated with hand injuries. A good pair or 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. And lastly, an option. If you're tired of being greasy and dirty all the iime, go to the drug store and buy a box ol disposable latex gloves like medical professionals wear. You can handle greasy parts. perform small tasks, wash parts, etc. all without getting dirty! These gloves take Jl surprising amount ol abuse without tearing and aren1 expensive. Note howeve..that it has been reported that some people are allergic to the latex or the powder used inside some gloves, so pay attention to what you buy. EYE & EAR PROTECTION • See Figures 3 and 4 Don't begin any job without a good pair of work goggles or impaci resistant glasses! When doing any kind ol work, it's all too easy to avoid eye injury through 8..18 Fig. 1 Three different types of work gloves. The box contains latex gloves this simple precaution. And don't just buy eye protection and leave it on the shelf. Wear it all the lime! Things have a habit of breaking, chipping, splashing, spraying, splintering and llying around. And, for some reason, your eye is always in the way! If you wear vision correcting glasses as a matter ol routine, get a pair made with pofycarbonate lenses. These lenses are impact resistant and are available at any optometrist. Often overlooked is hearing protection. Power equipment is noisy! Loud noises damage your ears. It's as simple as thai! The simplest and cheapest form of ear protection is a pair of noise-reducing ear plugs. Cheap insurance lor 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 !hose 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 shirllhal has seen be!!er days. That's line. 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 irs lor. When working in cold weather, a one-piece, thermal work outlit is invaluable. Most are rated to below zero (Fahrenheit) temperatures and are ruggedly constructed. Just look at what the marine mechanics are wearing and that should give you a clue as to what type ot clothing is good. Chemicals There is a whole range of chemicals that you'll find handy for maintenance work. The most common types are, lubricants, penetrants and sealers. Keep these handyonboard. There are also many chemicals that are used lor detailing or cleaning. When a particular chemical is not being used, keep it capped, upright and in a safe place. These substances may be llammable, may be irritants or might even be causlic 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 5 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 dillerent lasteners, BUT, NOT on any fastener which might vibrate loose causing a problem. If anti-seize is used on a fastener. it should be checked periodically lor proper lightness. lithium grease, chassis lube, silicone grease or a synthetic brake caliper grease can all be used pre!ly much interchangeably. All can be used for coating rust-prone fasteners and lor facilitating the assembly ol parts thai are a light 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. II may sound 00921'14 Fig. 2 Latex gloves come in handy when you are doing those messy jobs, like handling filters 0092rol Fig. 3 Don't begin any job without a good pair of work goggles or impact resistant glasses. Also good noise reducing earmuffs are cheap insurance to protect your hearing Fig. 4 Things have a habit of breaking, chipping, splashing, spraying, splintering and flying around. And, for some reason, your eye is always in the way TOOLS AND EQUIPMENT 2-3 Fig. 5 Antiseize, penetrating oil, lithium grease, electronic cleaner and silicone spray. These products have hundreds of uses and should be a part of your chemi· cal tool collection .(; e Fig. 6 Sealants are essential for prevent· ing leaks 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 dis· placed 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 besl friends when taking something apart that has corroded fasteners. Not only can they make a job easier. they can really help to avoid broken ami stripped fasteners. The most familiar penetrating oils are Liquid Wrench0 and WD-4.. A newer penetrant, PB Blaster& also works wen, Ttlese products nave hundreds ol uses. For your purposes. they are vital! Before disassembling any part (especially on an exhaust system). check the fasteners. If any appear rusted, soak them thoroughly wilh the penetrant and let them stand while you do something else (for particularly rusted or frozen parts you may need to soak them a lew days in advance). This simple act can save you hours oftedious work trying to extract a broken bolt or stud. SEALANTS • See Figures 6 and 7 Sealants are an indispensable part for certain tasks, especially il 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 ot conventional gasket material. The most common sealers are the non-hardening types such as Permate.o.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 stutf is really a good idea when you don't have enough hands or lingers 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 ol the mating surraces, a gasket shouldn't be used. This stulf, when used in conjunction with a conventional gasket, produces \he surest bonds. RTV does have its limitations though. When using Jhis material. you will have a time limit. It starts to set-up within 15 minutes or so, so you have to assemble the paris without delay. In addition, when squeezing the material out of the tube, don't drop any glops into the engine. The stulf will fonm and set and travel around the oil gallery, possibly plugging up a passage. Also, mosl types are nol fuel-proof. Check lhe tube for all cautions. 04892PIO Fig. 7 On some engines, RTV is used instead of gasket material to seal components CLEANERS • See Figures 8 and 9 There are two types of cleaners on the market today: parts cleaners and hand cleaners. The parts cleaners are lor lhe parts; the hand cleaners are for you. They are not interchangeable. Fig. 8 The new citrus hand cleaners not only work well, but they smell pretty good too. Choose one with pumice for added cleaning power Fig. 9 The use of hand lotion seals your hands and keeps dirt and grease from sticking to your skin 2-4 TOOLS AND EQUIPMENT There are many good, non-flammable,biodegradable parts cleaners onlhe mar· ket. These cleaning agents are sale lor you. the parts and the environment. Therefore. there is no reason to use flammable, caustic or toxic substances to clean your parts or tools. As far as hand cleaners go, lhe waterless types are the best. They have always been efficient at cleaning. but leave a pretty smelly odor. Recently though, just about all or them have eliminated the odor and added stutr that actually smells good. Make sure that you pick one lhat contains lanolin or some olher TOOLS • See Figure 10 Tools; this sub{ect could fill a completely separate manual. The lirst thing you will need to ask yourself, is just how involved do you plan to gel If you are serious about your maintenance you will want to gather a quality set oltools to make the job easier. and more enjoyable. BESIDES, TOOLS ARE FUN!Il Almost every do-it-yourselfer loves lo accumulate tools. Though most find a way to perform jobs with only a lew common tools, I hey tend to buy more over time, as money allows. So gathe..ing the tools necessary for maintenance does not have to be an expensive, overnigtlf:propositlon. When buying tools, the saying 'You get what you pay lor . : is absolutely lrue! Don, go cheap! Any hand tool that you buy should be drop forged and/or chrome vanadium. These two qualifies tell you that the lool is s!10ng enough for I he job. With any tool. go wilh a name that you'Ve heard of before. or, that is recommended buy your local professional retailer. Let's go over a list ol tools thai you'll need. Mosl ol the world uses the metric system. However. s0100 American-bunt engines and aftermarket accessories use standard fasteners. So. accumulate your tools accordIngly. Any good DIYer should have a decent sal of both U.S. and metric measure tools. ICQIIP8S Fig. 10 Socket holders, especially the magnetic type, are handy Items to keep tools In order moisture-replenishing additive. Cleaners not only remove grease and oil bul also skin oil. ,.Most women will tell you to use a hand lotion when you're all cleaned up. It's okay. Real men DO use hand lotion! 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 slicking to your skin. .. oon't be confused by terminology. Most advertising refers to "SAE and metric", or "standard and metric." Both are misnomers. The Soci· ety of Automotive Engineers (SAE) did not invent the English system of measurement; the English did. The SAE likes metrics just fine. Both English (U.S.) and metric measurements are SAE approved. Also, the current "standard" measurement IS metric. So, if it's not metric, It's U.S. measurement. Hand Tools SOCKET SETS • See Figures 11 thru 17 Socket sets are the most basic hand tools necessary tor repa·r and maintenance work. For our purposes, socket sets come in three drive sizes: v.. inch,% Inch and 112 inch. Drive size refers to lhe size of lhe drive lug on the ratchet. breaker bar or speed handle. Fig. 11 A% inch socket set is probably the most versatile tool In any mec.hanlc's tool box Fig. 14 Standard length sockets (top) are !CS91P3S Fig. 12 A swivel (U-Jolnt) adapter (left), a V.inch-to·%inch adapter {center) and a %Inch-to· Y.inch adapter (right) Fig. 13 Ratchets come in all sizes and configurations from rigid to swivel-headed good for just about all jobs. However, some bolls may require deep sockets (bottom) . .. 0092P20 Fig. 15 Hex-head fasteners retain many components on modern powerheads. These fasteners require a socket with a hex shaped driver Fig. 16 Tor.. drivers . A% inch set is probably the most versatile set in any mechanic"s tool box. It allows you to get into that the larger drive ratchets can't and gives you a range of larger sockets s\ilt strong enough lor heavy duly work. The socket set that you'll need should range in sizes tram% inch through 1 inch lor standard fasteners. and a 6mm through 19mm lor metric fasteners. You'll need a good 1h Inch 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 Y2 inch drive. V. Inch drive sets can be very handy in tight places. Though they usually dupli· cate functions o! the% inch set, V. inch drive sets are easier to use lor smaller bolts and nuts. As for the sockets themselves, they come in standard and deep lengths as well as6 or 12 point.6 and 12 points refers to how many sides are in the socket itself. Each has advantages. The 6 point socket is stronger and less prone to slipping which would strip a bolt head or nul. 12 point sockets are more common, usually less expensive and can operate beller in tight places where the ratchet handle can't swing Jar. Standard length sockets are good for just about art jobs. however, some studhead bolts, hard-to-reach bolts, nuts on longstuds, etc., require !he deep sockets. Most 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 lor lighter applications. Hex driver sockets are available individually or in sets just like convenlional sockets. More and more. manufacturers are using Torx.. head fasteners, which were once known as tamper resistant fasteners (because many people did not have tools with the necessary odd driver shape). They are still used where the manufacturer would prefer only knowledgeable mechanics or advanced Do-ll-Yoursellers (DIVers) to work. Torque Wrenches • See Figure 18 In most applications, a torque wrench can be used to assure proper installation of a fastener. Torque wrenches come in various designs and most stores will carry a Ooii!S21'30 Fig. 18 Three type.s of torque wrenches. Top to bottom: a% inch drive beam type that reads in inch lbs., a 1h inch drive clicker type and a 1f2 inch drive beam type TOOLS AND EQUIPMENT 2-5 Fig. 17 . . .and tamper resistant drivers are required to remove special fasteners installed by the manufacturers variety to suit your needs. A torque wrench should be used any time you have a specifictorque value for a fastener. Keep in mind that because there is no worldwide standardization of fasteners, the charts at the end of this section are a general guideline and should be used with caution. tf you are using the right tool tor the job, you should not have to strain to tighten a lastener. BEAM TYPE • See Figures 19 and 20 The beam type torque wrench is one of the most popular styles in use. II used properly, it can be lhe most accurate also. It consists of a pointer attached to the head that runs the length ol the flexible beam (shaft) to a scale located near the handle.As the wrench is pulled, the beam bends and lhe pointer indicates the torque using the scale. TCC$1039 Fig. 19 Parts of a beam type torque wrench 0092P33 Fig. 20 A beam type torque wrench consists of a pointer attached to the head that runs the length otlhe flexible beam (shaft) to a scale located near the handle 2-6 TOOLS AND EQUIPMENT CLICK (BREAKAWAY) TYPE t See Figures 21 and 22 Another popular torquewrench des1gn 1s the click type. The clicking mechanism maKes achieving the propet torque easy and most use ratchetlng head lor ease of boll installation. To use the click typewrench you pre-adjust it to a torQIA! setting. Once the torque is reached. the wrench has a reflex signaling feature that causes a momentarybreakaway or lhe tmque wreoch bo!I(I3 Olalll'll in both 6 and 12 point versions just like sockelsand each type has the same advantages and disadvantages as socke:s.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. f'.S for sizes. you'll probably need a range similar lo thai ol the sockets. about Y• Fig. 28 Occasionally you will lind a nut which requires a particularly large or par· ICtSilllJ tlcularty small wrench. Rest assured that Fig. 29 Pliers and cutters come In many the proper wrench to lit is available at shapes and sizes. You should have an your local tool store ass11rtment on hand Inch through 1 inch lor standard fasteners, or 6mm through 19mm for metric fasteners. As lor numbers. you'll need 2 of each size, since, in many instances, one wrench holds the nut while the other turns the boll. On most fasteners. the nut and boll are lhe 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 lind a nut which 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 talk· ing about safety here and buy a whole (read expensive) large wrench set. One extremely valuable type of wrench is the adjustable wrench. An adjustablewrench has a fixed upperjaw and a moveable lower jaw. The!owerjaw is moved by turning a threaded drum. The advantage of an adjustablewrench siits ability to be adjusted toJust about any size 1astene1. The main drawback ol an adjustlble wrench is the tower jaw's tendencyto move slightly under heavy pt'essure. This can cause the wrenCh to s!ip if itis not facing the right way.Pulling oo an adjus!able wrench in the proper direction will cause the jaws to lock in place. Adjustable wrcncnes come In a large range of sizes. measured bythe wrench length. PLIERS t See figure 29 Pliers are simply mechanicaJ fingers. They are. morethan anything, an extension of your hand. Al leasl 3 pair ot pliers are an absolute necessity-standard, needle nose and channel lock. In addftion to standard pliers there are the slip-joint, multi-position pliers such as Channellock"' pliers and locking pliers, such as Vise Grips11 • 6IWJID Ag. 30 Tllree types of hammers. Top to bottom: ball peen, rubber dead-blow. and plastic 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 orr 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 pipejawed. 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 thicknesses for all types of slotted fasteners. Phifflps screwdrivers come in sizes with number designationsfrom 1 on up, with the lower numberdesignating the smaller size. Screwdrivers can be purchased separately or In sets HAMMERS t See Figure 30 You always need a hammerlor just about any kindof work. You need a ball-oeen hammer lor most rnelalwork when using dnvers and other lii.s a specific blend of metals in their zincs. If you are using zincs with the wrong blend of metals, !hey may erode more quickly or leave you with diminished protection. 047031'118 Fig. 25 Such extensive erosion of a trim tab compared with a new tab suggests an electrolysis problem or complete disregard tor periodic maintenance 3-8 MAINTENANCE BOAT MAINTENANCE Batteries 0470!1f!Yl Fig.26 Explosive hydrogen gas is normally released from the cells under a wide range of circumstances. This battery exploded when the gas ignited from someone smoking in the area when the caps were removed. Such an explosion could also be caused by a spark from the battery terminals During hot weather and periods ol heavy use, the electrolyte level should lle 0471l9ro4 Fig. 27 A battery post cleaner is used to clean the battery posts . . . Fig. 28 . ..and the battery terminals 0471l9ro3 Fig. 29 Testing the electrolyte specific gravity using a temperature corrected hydrometer MAINTENANCE • See Figure 26 Batteries require periodic servicing and a definite maintenance program will ensure extended life. If the battery should lest satisfactorily but still fails to perform properly,one of four problems could be the cause. 1. An accessory might have accidentally been left on overnight or for a long period during the day. Such an oversight would result in a discharged battery. 2. Using moreelectricalpower !han thestatorassembly orlightingcoil can replace wouldresult in an undercharged condition. 3. Adefect in the charging system. A faulty stator assembly or lightingcoil, defective rectifier or high resistance somewhere in !hesystem could cause the battery to become undercharged. 4. Failure to maintain the battery in goodorder. This might include a lowlevelof electrolyte in thecells,lqose or dirty cable connectionsat thebaltery terminals or possibly an excessivetfnirtybattery top. The most common procedure for maintaining a battery is tocheck the electrolyte level.This is done lly removing the cell capsand visually observing the level in the cells.The bottom of each cell has a split ventwhich will cause the surface of the electrolyteto appear distortedwhen it makes contact. When the distortion first appearsat the boltom of the split vent. the electrolyte level is correct. checkedmore often than duringnormaloperation. Add distilled waterto bring the level ol electrolytein each cell to the proper level.Takecarenotto overfill,because addingan excessive amount of water will cause loss of electrolyte and any loss will resultin poor performance, short llattery life and will contribute quickly to corrosion. .-Never add electrolyte from another battery. Use only distilled water. CLEANING • See Figures 27 and 28 Dirt and corrosion should be cleaned fromlhe battery as soon as it is discovered. Any accumulation of acidfilm or dirt will permit current to flow between the terminals. Such a current flow will drain the ballery over a period of time. Clean the exterior ol the battery with a solution of dilutedammoniaor apaste madelrom baking soda and water. This neutralize any acid which may be present Flush the cleaning solutionoil withplenty of clean water. ,.. Take care to prevent any of the neutralizing solution from entering the cells. Apoor contact at the terminals will add resistance tothe charging circuit. This resistance will cause the voltage regulator to register a fully charged battery and thus cuidown on the stator assembly orlightingcoil output adding to the low battery chargeproblem. At least oncea season, the battery terminals and callle clamps should be cleaned. Loosen the clamps andremove the cables, negative cable first. On batteries with lop mounted posts, the use of a puller specially made lor this purposeis recommended. These are inexpensive and available in most parts slores. Clean the cable clamps and !he ballery terminal with awire brush,until all corro· sian,grease, etc.,is removed and the metal is shiny. II is especially importantto clean the inside ofthe clamp thoroughly (a wire brush is useful here), since a small depositof foreign material or oxidation !here will prevent a soundelectrical connectionand inhibit either starting or charging. It is also a good idea lo apply some dielectricgrease to the terminal,as this will aid in the prevention ofcorrosion. Aller theclamps 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. Give the clamps and terminals a thin external coating of grease after installation, to retard corrosion. Check the cables at the same lime that the terminals are cleaned. li the insulation is crackedor broken or if its end is frayed,that cable should be replaced with a new one of the samelength and gauge. TESTING • See Figure 29 Ahydrometer isa device tomeasurethe percentage orsulfuric acid in the battery electrolyte in terms of specific gravity.When the condition of lhe battery drops from fully charged to discharged, the acid leaves the solution and enters 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 80°F {27°C). If the hydrometer is used at any other temperature, hotter or colder, a correction factor must be applied. ,..Remember, 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 thermometer/temperature correction table In the lower portion, as illustrated in the accompanying illustra:ion. By knowing the air temperature around the battery and from the table, a correction factor may be applied to the specific gravity reading of the hydrometer floal. In this manner, an accurate determination may be made as to the condition ol 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 leas! 14 hour of charging at a high rate to thoroughly mix the electrolyte with the new water. This lime 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 cou..t lemperature before laking a reading. 4. Be sure to hold the hydrometer vertically dnd 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 lloaling. 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. Aller 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 Green band range for all cells. the condition of the battery is satisfactory. If the level is within the white band lor all celts, 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 wilt 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. li the level fails to rise above the Red band after charging, the only solution is to replace the battery. A check of the electrolyte in the battery should be on the maintenance schedule of any boat. A hydrometer reading of 1.300 or in the green band, indicates the battery is in satisfactory condition. If the reading is 1.150 or in the red band. the battery must be charged. STORAGE If the boat is to be laid up for the winter or for more than a few weeks, special attention must be given to the battery to prevent complete discharge or possible damage to the terminals and wiring. Before putting the boat in storage, disconnect MAINTENANCE 3-9 and remove the batteries. Clean them thoroughly of any dirt or corrosion and then charge them to full specific gravity reading. 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. Storing the 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 tiller caps. All 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 exercisedin selecting the battery storage area. A fully-charged battery will freeze at about 60°below zero. A discharged battery, almost dead, will have ice forming at about 19° above zero. Fiberglass Hull • See Figures 30, 31 and 32 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. II 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 lout 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. II growth has developed on the bottom, it can be removed with a 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 !rom your face and hands. The fumes are toxic. Therefore, work in a welf-ventilaled area or if outside, keep your face on the windward side of the work. Barnacles have a nasty habit of making their home on the bottom of boats which 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 crusiaceans have attached themselves to the hull, extra work will be required to bring lhe bottom back to a satisfactory condition. First. if practical, put the boat into a body ol fresh water and allow it to remain lor a few days. A large percentage ol the growth can be removed in this manner. II 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 fasl. These can be removed with sandpaper. Sfl.STKOO Fig. 30 In areas where marine growth Is a problem, a coating of anti-foul bottom paint should be applied Sfi.Sll<5S Fig. 31 The best way to care for a fiberglass hull is to wash it thoroughly 048921'C. Fig. 32 Fiberglass, vinyl and rubber care products, such as those available from Meguiar's are available to protect every part of your boat 3-10 MAINTENANCE TUNE-UP Introduction A proper tune-up is the key to long and trouble-free outboard life and thework can yield its own rewards. Studies have shown that a properly tuned and maintained outboard can achieve beltef 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 problllfns 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 problefns 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, 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 performing service work in the proper sequence cannot be over efnphasized. Before making 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 lastservice. 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 conlaining the appropriate instructions. Compression Test PRIMARY COMPRESSION TEST Because the 2-stroke powerhead is a pump, the crankcase must be sealed against pressure created on the down stroke of the piston and vacuum created when the piston moves toward top dead center. If there are air leaks into the crankcase, insufficient fuel will be brought into the crankcase and into the cylinder for normal combustion. ,..If it is a very small leak, the powerhead will run poorly, because the fuel mixture will be lean and cylinder temperatures will be hotter than normal. Air leaks are possible around any seal, 0-ring, cylinder block mating surface or gasket. Always replace 0-rings, gaskets and seals when service work is performed. If the powerhead is running. soapy water can be sprayed onto the suspected sealing areas. If bubbles develop, there is a leak al tha! point. Oil around sealing points and on ignition parts under the flywheel indicates a crankcase leak. The base of the powerhead and lower crankshah seal is impossible to check on an installed powllfhead. 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. Adapter plates available from tool manufacturers to seal the inlet, exhaust and baseof the powerhead. Adapter plates can also be manufactured by cutting metal block off plates from pieces oi plate steel or aluminum. A pattern made from the gaskets can be used for an accurate shape. Seal these plates using rubber or silicone gasket making compound. 1. Install adapter plates over the intake ports and !he exhaust ports to completely seal the powerhead. ,..When installing the adapter plates, make sure to leave the water jacket holes open. 2. Into one adapter, place an air fitting which will accept a hand air pump. 3. Using the hand pump (or another regulated air source), pressurize the crankcase to five pounds of pressure. 4. Spray soapy water around the lower seal area and other sealed areas watching tor bubbles which indicate a leaking point. 5. Turn the powerhead upside down and fill the water jacket with water. It bubbles show up in the in the water when a positive pressure is applied to the crankcase. there may be cracks or corrosion holes in the cooling system passages. These holes can cause a loss of cooling system effectiveness and lead to overheating. 6. After the pressure test is completoo, pull a vacuum to stress the seals in the opposite direction and watch for a pressure drop. 7. Note the leaking areas and replace the seals or gaskets. SECONDARY COMPRESSION TEST t See Figure 33 The actual pressure measured during a secondary compression test is not as importantas the variation from cylinder tocylinder. On multi-cylinder powefheads, a variation of 15 psi or more is considered questionable. On single cylinder powerheads. a drop of 15 psi from the normal compression pressure you established when it was new is cause for concern (you did do a compres_slon test on it when it was new. didn't you?). ,..If the powerhead been in storage for an extended period, the piston rings may have relaxed. This will often lead to initially low and misleading readings. Always run an engine to operating temperature to ensure that the reading you get is accurate. 1. Disable the ignition system by removing the lanyard clip. If you do not have a lanyard, take a wire jumper lead and connect one end to a good engine ground and the other end to the metal connector inside the spark plug boot, using one jumper !or each plug wire. Never simply disconnect all the plug wires. ** CAUTION Removing all the spark plugs and cranking over the powerhead can lead to an explosion if raw fuel/oil sprays out of the plug holes. A plug wire could spark and ignite this mix outside of the combustion chamber if it isn't grounded to the engine. 2. Remove all the spark plugs and be sure to keep them in order. Carefully inspect the plugs, looking for any inconsistency in coloration and for any sign of water or rust near the Lip. 3. Thread the compression gauge into the No. 1 spark-plug hole, taking care to not crossthread the fitting. 4. Open the throttle to the wide open throllie position and hold it there. ,..Some engines allow only minimal opening if the gearshift is in neutral, to guard against over·revving. 5. Crank over lhe engine anequal number ot times for each cylinder you test, zeroing the gauge for each cylinder. 6. If you have electric start, count the number of seconds you count. On manual start. pull the starter rope lour to five times for each cylinder you are testing. 7. Record your readings from each cylinder. When all cylinders are tested, comparethe readings and determine if pressures are within the 15 psi criterion. 8. It compression readings are lower than normal for any cylinders. try a ·wet" compression test, which will tefnporarily seal the piston rings and determine if they are the cause of the tow reading. 9. 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. Ifthe compression rises noticeably, the piston rings are sticking. You may be able to cure the problem by de-carboning the powerhead. b. If the dry compression was really low and no change is evident during the wet test, the cylinder is dead. The piston and/or are worn beyond specification and a powerhead overhaul or replacement is necessary. Fig. 33 Typical two-stroke powerhead secondary compression test 10. 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. Spark Plugs The spark plug performs four main functions: • It fi lis a hole in the cylinder head. • It acts as a dielectric insulator for the ignition system. • It provides spark for the combustion process to occur. • It removes heat from the combustion chamber. It is important to remember that spark plugs do not create heal, 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, especially in two stroke engine. 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. By evaluating the appearance of the spark plug's firing tip, visual cues can be seen to accurately determine the engine's overall operating condition, get a feel for air/fuel ratios and even diagnose driveability probtems. As spark plugs grow older, lhey lose their sharp edges and material from the center and ground electrodes is slowly eroded 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 are 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 nel¥ edges) effectively restores the ignition system's efficiency and reduces the percentage of misfires. restoring power, economy and reducing emissions. How long spark plugs last will depend on a variety of factors. including engine compression, fuel used, gap, center/ground electrode material and the conditions In which the outboard is operated. SPARK PLUG HEAT RANGE • See Figure 34 Spark plug heal range is the aoilily of the plug to dissipate heat from the combustion chamoer. The longer the insulator (or the farther it extends into the engine). the honer the plug will operate; the shorter the insulator (the closer the electrode is to the block's cooling passages) the cooler it wlfl operate. Selecting a spark plug with the proper heat range will ensure that the tip will maintain a temperature high enough to prevent fouling, yet oe cool enough to prevent pre-ignition. A plug that absorbs little heat and remains too cool will quickly accumulate deposits of oi I and car !Jon since it is not hot enough to burn them off. This leads to plug fouling and consequently to misfiring. A plug that aosorbs too much heal will have no deposits but, due lo the excessive heat. the electrodes will burn away quickly and might possibly lead to pre-ignition or other ignition problems. Pre-ignition takes place when plug lips get so hot I hal they glow sufficiently to ignite the air/fuel mixture before the actual spark occurs. This early ignition will usually cause a pinging during heavy loads and if not corrected will result in severe engine damage. While there are many other things that can cause pre-ignition, HEAVY lOAOS. HIGH SPEEOS SHOAT tnsotatot T 'P J.:..sl He.al Tun stet LOWE A He•l Range COLO PLUG Fig. 34 Spark Plug heat range SHORT TRIP STOP·AI Step 5 1 -Trigger Unk Rod OSI93GIO Step 6 ** CAUTION Do not attempt to pry the throttle link rod free of the throttle cam. Such action could very well damage the throttle cam. 5. With the idle speed screw against the stop. adjust the idle speed screw until the powerhead has reached normal operating temperature and is operating with the timing at the setting specified in the "Tune-Up Specifications' chart. 6. Hold the throtile cam In position with the throttle roller just touching the cam and with lhe center ol lhe roller atigned with the scribe mark on the cam. Continue to hold this position and at the same time, adjust the length of the throNie link rod untilit will just slip over l.lle throttle lever anchor ball. 7. Rotate the idle speed screw slightly to obtain the proper idle speed with the unit in FORWARD. IDLE SPEED & MIXTURE • See Figure 58 1. Connect a tachometer lo the powerhead. 2. Start the powerhead and allow il lo reach operating temperature. 3. With the engine running at idle in FORWARD gear adjust the idle speed OS193GI2 Fig. 58 Place the engine in forward and adjust the idle speed screw MAINTENANCE 3-21 screw to obtain the recommended idle speed found in the "Tune-Up Specifications" chart. .-Make an effort to prevent the powerhead from shutting down during the following adjustments. 4. Move the throttle to the idle speed position and allow the RPM to stabilize. Push the primer/fast idle knob inward and then rotate it to the full counterclockwise position. 5. With the powerhead operating at idle rpm, rotate the idle mixture screw counterclockwise until the powerhead begins Ia misfire because of an over-rich fuel mixture. 6. Slowly rotate the idle mixture screw clockwise and count the turns until the powerhead is operating evenly and the RPM increases. Continue rotating the mixture screw clockwise until the powerhead begins to slow down and eventually begins to misfire because of a too lean air/fuel mixture. 7. Count and move the idle mixture screw back to the hailway point between the too rich mixture and the too lean mixture . .-oo not adjust the mixture any leaner than necessary to obtain a smooth idle. It is better lor the mixture to be on the "too rich" side rather than the "too lean" side. 8. Check lor a too lean mixture on acceleration (engine will hesitate or stall on acceleration). Readjust the mixture if necessary. 9. Readjust the idle speed, as necessary and insta!l the access plug. CARBURETOR THROTTLE CAM • See Figure 61 1. The throttle cam adjustment cannot be made unless the carburetor throtlle shutter is completely closed 1herefore,the idle speed screw may have to be backed out; the dashpot adjusted away from the throtlle cam; and/or the neutral RPM screw rotated counterclockwise before a proper throttre cam/roller alignment can be made. 2. With the engine shut down, move the throltfe cam to check the cam adjustment. 1he bottom scribe line on the cam should be aligned with the center ol the throttle roller and the roller just barely touchesthe cam. 3. if an adjustment is necessary, first loosen the hex bolt and with the punch mark on the eccentric facing down and forward of the hex bo!t axis, rotate the eccentric counterclockwise to reposition the cam until the throttle roller is aligned with the scribe line. DASHPOT ADJUSTMENT • See Figure 62 The stem of the dashpot should be fully depressed when lhe powerhead is operating at the specified idle rpm. Adjust !he dashpot to obtain this condition. FAST IDLE SPEED • See Figure 59 1. Connect a tachometer and timing light to the powerhead. 2. Start the powerhead and allow it to reach operating temperature. 3. Push the primer/fast idle knob in lully and turn clockwise. 4. Place the lower unit in FORWARD gear and adjust the last idle speed screw to obtain the recommended idle speed found in the "Tune-Up Specifications" chart. STARTER INTERLOCK ADJUSTMENT 1990-93 • See Figure 60 1. Shiftthe engine into the NEUTRAL position and shut the engine olf. 2. Pull the fast idle knob to the full out position. 3. Adjust the interlock screw to permit the interlock lever to clear the ratchet on the starter sheave. 4. Once the adjustment is made, pull the starter cord to verify that the powerhead can be manually started. 1994-00 1. Shift the engine into the NEUTRAL position and shut the engine off. 2. Push the primer/fast idle knob in fully and turn clockwise. 3. Make sure !he throtlle is in the idle position 4. Adjust the interlock screw to permit the interlock lever to clear the ratchet on the starter sheave 5. Once the adjustment is made, pull the starter cord to verily that the powerhead can be manually started. I· Fast ldla Speed Screw 2.. Primer E.nrichener Fig. 62 Adjust the stem on the dashpot so that it is fully depressed when at idle speed 05193G14 Fig. 59 With the engine in neutral and the primer enrlchener pushed to the full in and full clockwise position, adjust the last idle speed screw to specification Fig. 60 Turning the interlock screw will adjust the interlock lever OJS7Efl6 Fig. 61 Location ol the components necessary to adjust the throttle cam-20 and 25hp 3-22 MAINTENANCE 1 •C-am FOflowef Rater 2· Tnronle C8m 3· cam FOllower Screw4. ldie Speed Screw 1•Ttwottle Cam 2· Unk ROd 3all OS1!1JG26 05193627 Fig. 64 With the throttle at idle position, turn the Idle speed screw clockwise in 1•Cam tolfO"Ner Sctew 2•ThronJe Shutter Positioner3· Jam Nu1 4• idle Speed Screw Fig. 63 With the cam follower resting on the throttle cam, lighten the cam follower screw until a gap of 0.005-0.040 in. (0.13-1.02 mm) is achieved between the throttle cam and cam follower OS1!13G2.. Fig. 65 Components used to adjust idle speed 05193G29 Fig. 66 With the engine running at idle speed and the gear box in the FORWARD position, tum the mixture screw in (clockwise) until the engine starts to bog down and misfire. Back out the screw Y. turn or more 30 and 40 HP (2-Cylinder) Perform synchronization of the 30 and 40hp (2-Cylinder) powerheads in the following order: perform preliminary adjustments. set cam follower, set the ignition timing, set the idle speed and mixture, set oil pump linkage and finally, test drive the boat to insure proper full throtlle speed. ** CAUTION Water must circulate through the powerhead any time it is running to prevent damage to the water pump and possible powerhead overheating. Never run the engine over 3000 RPM without an adequate load applied to the propeller. PRELIMINARY ADJUSTMENTS 1. Loosen the cam follower screw and turn the idle speed screw until it no longer touches the lhroHie arm and the throttle plates are fully closed. 2. Rotate the idle mixture screw slowly clockwise (inward) until it barely seats and then back it out counterclockwise the number of turns specified in the "Tune-Up Specifications" charl. CAM FOLLOWER • See Figures 63 and 64 1. Loosen the throttle cable jam nuts. 2. With the throttle at the idle position, place the cam follower roller against the throttle cam. Center the roller with raised mark on the throttle cam by adjusting lhe position of the throtlle cable sleeves in the mounting bracket. ,..When positioning throttle cables, a minimum of V.& in. (1.59 mm) to a maximum of 'Is in. (3.18 mm) slack must be allowed to prevent throttle cables from binding. (Rock throttle cam side to side and mea· sure the amount of throttle cam travel at link rod ball). 3. Tighten the throttle cable jam nuts. 4. With the cam follower resting on the throttle cam, tighten the cam follower screw. 5. With the throttle at idle position, turn the idle speed screw clockwise in until a gap of 0.005-0.040 in. (0.13-1.02 mm) is achieved between the throttle cam and cam follower. IGNITION TIMING ,..Due to the electronic ignition system design, there are no liming adjustments required for the 30 or 40hp (2-Cylinder) powerheads. How· ever, the timing can be verified using the following procedure. 1. Connect a tachometer and timing light to the powemead. 2. Start lhe powerhead and allow it to reach operating temperature. 3. Move the shift lever to lhe FORWARD position and insure the throttle is a idle position. 4. Check lhe maximum advance timing mark on the flywheel. The mark should be aligned with the pointer. Timing specifications can be found in the "Tune-Up Specifications" chart. ,.. The idle stabilization feature of these engines will cause the timing to fluctuate 2-3• at idle. 5. 6. Move the throttle to the wide open throttle position and recheck the timing. If lhe ignition timing is nol within specification, see the "Ignition and Electri· cal" section for troubleshooting procedures. 7. After the timing set. shut down the powerhead and disconnect the tachometer and timing light. IDLE SPEED & MIXTURE • See Figures 65 and 66 1. Connect a tachometer to the powerhead. 2. Start the powerhead and allow it to reach operating temperature. 3. With the engine running at idle in FORWARD gear adjust lhe idle speed screw to obtain the recommended idle speed found in the "Tune-Up Specifications" chart. ,..Make an effort to prevent the powerhead from shutting down during the following adjustments. 4. Move the throttle to the idle speed position and allow the RPM lo stabilize. Push the primer/las! idle knob inward and then rotate it to the full counlerclockwise position. 5. With the powemead operating at idle rpm, rotate the idle mixture screw coun ..terclockwise until the powerhead begins to misfire because of an over-rich fuel mix· ture. 6. Slowly rolate the idle mixture screw clockwise and count the turns until the powerhead is operating evenly and the RPM increases. Continue rotating lhe mixture ··:r screw clockwise until the powerhead begins to slow down and eventually begins to misfire because of a too lean air/fuel mixture. 7. Count and move the idle mixture screw back to the halfway point between the too rich mixture and the too lean mixture. ,-oo not adjust the mixture any leaner than necessary to obtaina smooth idle. It is better for the mixture to be onthe "too rich" side rather than the "too lean" side. 8. Check for a too lean mixture on acceleration (engine will hesitate or stall on acceleration). Readjust the mixture if necessary. 9. Readjust the idlespeed. as necessary and install the access plug. OIL PUMP t See Figure 67 ,..The oil pump linkage must be synchronized to the throttle linkage any time the throttle linkage isadjusted While holding the lhrottle arm at idle position. adjust the length of the link rod so thestamped mark of the oil pump body aligns with the stamped mark of the oilpump lever. 1•Al)grynen1 M81k 2· UnkRod 3-0il'ump......., Fig. 67 Oil pump adjustment marks 40 HP (4-Cylinder) 0$193C28 Perform synchronization of the 40hp (4-Cylinder) powerheads in the following order: perform preliminary adjustments. set the throttle plate. set the ignition timing, setthe lull throttle stop, set the idle speed and mixture. and finally, test drive the boat to insure proper full throttle speed. ** CAUTION Water must circulate through the powerhead any time it is running to prevent damage to the water pump and possible powerhead overheating. Never run the engine over 3000 RPM without an adequate load applied to the propeller. Step3 Step4 MAINTENANCE 3-23 PRELIMINARY ADJUSTMENTS 1. Disconnect thethrottlecables from the throttle lever arm. 2. Rotate the idle mixture screw slowly clockwise (inward) until it barely seats and then back it out counterclockwise the number of turns specified in the ·rune-Up Specifications" chart. CARBURETOR SYNCHRONIZATION 1. Turn the idle speed screw counterclockwise until the throttle cam is not louching the lhro!tle arm and the throttle plates on lhe upper carburetor are fully closed. 2. Loosen theadjustmentscrew on the lie bar connecting the carburetors. 3. Open both carburetor throttle plates and allow them to close against spring pressure. Verify that both carburetor throttle plates are fully closed. 4. Hold thetie bar in position and tighten the adjustment screw. 5. Once again, open the carburetor throttle plates (this time they should work in unison) and allow them to close against spring pressure. VerilY that both carburetor throttle plates are working in unison. IGNITION TIMING Pick-UpTiming ,.After all timing adjustments have been made, the idle RPM screw will have to be readjusted to provide the proper idle RPM for the engine. 199{}-93 t See accompanying illustrations 1. Connect a tachometer and timing light to the powerhead. 2. Crank the engine while pointing the liming light al lhe flywheel. 3. Slowlyadvance the throttle spark arm until the liming mark is aligned with the "V". 4. Hold thethrottle spark arm stationary and at the same lime, adjust the idle RPM screw until the screw contacts the stop. 5. VerilYthe primary timing mark is still aligned with the "V'. 6. Loosen the fwo throttle actuator plate retaining screws. 7. Hold the throttle spark arm against the idle RPM stop screw and at the same time rotate the actuator plate until the primary throttle cam just contacts the pick-up arm on the carburetor cluster. Tighten the actuator p!ate retaining screws to hold this adjustment. 1994-97 1. Connect a tachometer and timing light to the powerhead. 2. Start the powerhead and allow it to reach operating temperature. 3. Move the shill lever to the FORWARD position and insure the throttleis a idle position. 4. Use a timing light to read the current timing with the powerhead at idle speed. 5. Hold the throttle spark arm stationary and at the same time, adjust the idle RPM screw until the proper liming is achieved. Timing specifications can befound in the "Tune-Up Specifications• chart 6. Stop the powerhead and loosen the two throttle actuator plate retaining screws. St.ep7 3-24 MAINTENANCE 7. Hold lhe throttle spar.. arm agai'lsl the ld!e RPM stop saew and at the same time ro!ale :he a:tuator plate until the primary throttle cam jus! contacts the pick-up arm on the carburetor cluster. nghten the actuator plate retaining screws lo hold this adjustment S..condary Pick-Up t See Figure 68 1. Loosen the locknut on thesecondary throttle pick-up screw. 2. Advance the !hrollte lever until the maxJmum advance screw is against the stop on the exhaust cover. 3. Hold the throttle lever against the slop and at the same lirrte. adjust thesecondary throttle pic<-up scsew until the end ol the screw contacts the secondary lever ol the carburetor cluster 4. Tighten the locknut lo hold this adjuslmenl Maximum Advance Timing • See Figure 69 1. Loosen the locknut on the maximum advance screw. 2. Move throttle lever until the maximum advancescrew is against the stop and hold the lhroHie in this-position. 3. Adjust the secondary thro!llcpick-up screw so isjustbarely contacts the secondary lever. 4. Tighten the seconoary throttle pick-up screw tocknul lo hold this position. FULL THROTILE STOP t See Figures 70 and 71 1. Loosen the locknut on the maximum advance screw. 2. Move throttle lever untilfull throttle stop screw is against the stop and hold the throttle In this position. 3. Adjust the lull throtue stop screw so the carburetor throllle valves are in the wide open throllle position. 4 Ensure that the carburetor thro!Ue valves are not serving as the throtlle stop. There should be O.OHHl.015 in. (0.25-0.38mm) free play between the secondary pick-up screw and the secondary lever. If-there is insufficient tree-play, readjust !he full throtlle StOP SClCW. 5. Tighten the lull lhroltlc stop screw loc THROTTLE CAM • See Figure 87 1. Check to be sure the remote control throttle lever is In the NEUTRAL and idle position. 2. Loosen the cam follower screw to allow the cam to move freely. 3. Hold the throttle lever against the idle stop and check the alignment mark on lhrottle cam. The mark should be centered with the cam roller. If the mark is not aligned, loosen the locknul on the idle stop screw and adjust the idle stop screw until the mark on the cam is centered in the cam roller. 4. Tighten the locknut on the idle slop screw to hold the adjustment. 5. Do not tighten the cam follower screw at this time. CARBURETOR SYNCHRONIZATION 1994-95 • See Figures 88 and 89 1. Loosen the two carburetor synchronization screws on the two upper carbure tor linkage arms. 2. Check to be sure the shuller plates in the carburetors are completely closed. 3. Hold the throttle lever with the idle stop screws against the idle stop. 4. Move the cam follower roller next to the throttle cam until the roller barely makes contact with the throtlle cam. 5. Carefully, tighten the carburetor synchronization screws and the cam follower roller screw without disturbing any ol the adjustments. 6. Move the throttle lever lrom idle to hall throttle while checkingthe shutter plates on all three carburetors. The shutters should open and close simultaneously. Repeat this step if any shutter plate lags. 7. Move lhe throttle lever to the wide open throllle position. loosen the locknut and adjust the lull throttle stop screw until the carburetor shuUers are tully open at wide open throttle. Check to be sure the throtlle shutters do not act as throttle stops. Use a feeler gauge and check for .o1o-.015" (.25mm-.38mm) clearance between the cam follower roller and the lhroltle cam. Tighten the locknut on the lull throttle stop screw to hold this adjustment. 1996-97 1. Adjust the idle stop screw until the bend in the linkage is % in. (5.3mm) from the crankcase casting. The threaded idle stop boss on the back side of the throttle arm should be close to the middle of the idle slop screw. 2. loosen the carburetor synchronization screws to allow the shutter plates to close completely. . 3. Positi..n the throttle Ieve.. so that the idle stop screw is against the idle stop. Without movmg the linkage, rellghlen the center screw first and then the upper and lower screws. 4. Move the throtlle lever from idle to half throttle while checking the shutter plales on all three carburetors. The shutters should open and close simultaneously. Repeat this step if any shutter plate lags. 5. Move the throttle lever to the wide open throttle position. Loosen the locknut and adjust the full throttle stop screw until the carburetor shutters are fully open at MAINTENANCE 3-33 2. Check the alignment mark on the oil pump lever. The mark should be aligned with the casting mark on the oil pump body. 3. If the marks are not aligned, disconnect the linkage rod from the oil pump lever. 4. Adjust the rod end to align the mark on the oil pump body with the mark on the lever. 5. Connect the rod end onto the oil pump lever. THROTTLE POSITION SENSOR (TPS) • See Figure 91 The TPS transmits throttle position Information to the engine controller in the form of a low voltage signal. This low voltage signal will range from .950 VDC at the idle position to 3.91VDC at wide open throttle selling. A lower voltage setting will cause the powerhead liming to retard and a higher voltage will advance the timing. A 0.050 voll change in the TPI setting, results in a 1• change in the power head timing. Alignment and adjustment of the TPS is a critical step in the timing and synchronizing of the powerhead. 1. Disconnect the TPS from the ignition harness. 2. Connect a multimeter to the harness using a Mercury Test Lead Assembly (84-825207A 1) or equivalefll 3. On 1994-95 modeli{connect the Black m£;er lead to the Black test lead and the Red meter lead to the White test lead. 4. On 1996-97 models. connect the Black meter lead to the White test lead and the Red meter lead to the Red test lead. 5. loosen the screws on the TPS bracket and turn the ignition switch ON. 6. Rotate the TPS to obtain a voltage of 0.9-1.00, then lighten the screws. 7. Disconnect the lhrollle control cable and slowly rotate the lhrollle lever to the full open position while monitoring the TPS voltage The voltage reading should increase and decrease smoothly. 8. Maximum voltage at wide open throttle should be 3.7-3.9 volls. ,.II maximum voltage is not correct, verify that the full throttle stop is set correctly. 9. Remove the test leads and connect the TPS to the harness. CRANKSHAFT POSITION SENSOR • See Figure 92 1. Remove the flywheel cover, If il is sllll in place 2. Rotate the llywheel clockwise by hand and align one of the flywheel sensor teeth directly in line (perpendicular), with the crankshaft position sensor. 3. Using a feeler gauge, measure the gap between the sensor and flywheel tooth. The allowable gap measurement is 0.02o-0.060 in. (0.51-1.53 mm). lf the gap is incorrect, loosen the two sensor bracket bolls. 4. Set the gap to the correct measurement and tighten the two sensor bracket bol!s. with the lower unit in FORWARD gear and the propeller under an actual load condition. 1. Start the powerhead and allow it to warm to operating temperature. 2. Place the outboard into FORWARD gear and monitor the powerhead rpm. If the powerhead RPM is not correct, verify carburetor synchronization and/or carburetor mixture settings. If synchronization and fuel mixture are correct, the idle speed may be adjusted by repositioning the TPS sensor. See ''TPS Adjustmenr' this section. 3. With the end of the lhroH!e cable connected to the throttle lever anchor pin hold the throttle lever against the idle slop. Adjust the throttle cable barrel until II will slip Into the barrel retainer on the cable anchor bracket. If necessary, adjust the throttle cable barrel until there is a very light preload on the throttle lever against the idle stop. ,.An excessive preload on the throttle cable will cause difficulty when shifting between gears. 4. The preload may be easily checked by placing a piece of paper between the idle stop screw and the idle slop and then withdrawing it. If Ihe paper does not tear but drag can be felt, the preload is correct. Adjust the cable barrel, if necessary, to obtain the proper preload ;ust described. Install the powerhead cowling. 250 and 275 HP Perform synchronization of the 250 and 275hp powerheads in the following order: set the timing pointer. synchronize the carburetors. set the ignition timing, set the iull throttle stop, adjust the oil pump linkage, set the idle speed and finally, test drive the boat to insure proper full throttle speed. ** CAUTION Water must circulate through the powerhead any lime it is running to prevent damage to the water pump and possible powerhead overheating. Never run the engine over 3000 RPM without an adequate load applied to the propeller. IGNITION TIMING Timing Pointer 1. Remove ai I spark plugs. 2. Install a dial indicator into the No.1 (top cylinder starboard bank), spark plug opening. Slowly rotate the flywheel counterclockwise unlil lhe dial indicator needle isV. turn beyond the .526 in. mark. 3. Slowly rotate the flywheel back clockwise unlil lhe dial indicator is exactly at the .557 in. (14.14 mm) mark. Observe the timing pointer on the powerhead and lhe .557 in. (14.14 mm) mark on the flywheel. 4. If the timing pointer is not exactly on the mark, loosen the pointer adjustment '{' 5. Install the flywheel cover. IDLE SPEED ,.The following procedures must be performed with the outboard in a test tank or the boat and outboard in a body of water. The idle speed adjustment procedures can only be preformed with the outboard running bolt and align the pointer with the .557 in. (14.14 mm)mark on the flywheel. 5. Tighten the pointer adjustment bolt. Preliminary Timing Adjustments • See Figure 93 1. Measure the length of the trigger link rod from the center line of the 90°bend to the edge of the locknut 037J!iCOO Fig. 91 Using the TPS test lead and multimeter to check TPS voltage 03730007 Fig. 92 After removing the flywheel cover it is possible to check the gap on the crankshaft position sensor Fig. 93 Measure the length of the trigger rod 3-34 MAINTENANCE 2. The dimension must be 'Y•e in. (17.5mm) for proper timing adjustment. 3. If the measurement is not as specified, disconnect the link rod and adjust. 4. Disconnect the idle stabilizer module at the White/Black wire bullet connector. Tape the connector to prevent accidental grounding. Pick-Up Timing • See Figure 94 1. Disconnect the spark plug leads from the plugs and ground each lead to the powerhead. 2. Connect a timing light to the powerhead. 3. Place the remote shill lever in the NEUTRAL position. 4. Hold the throttle lever against the idle stop. 5. Crank the powerhead with the starter motor and at the same time, aim the liming light at the flywheel cover liming pointer. 6. Adjust the primary pick-up screw until the timing pointer aligns with the liming mark specified in the "Tune-Up Specifications" chart. 7. Tighten the locknut to hold this position. Maximum Advance Timing t See Figure 95 -<> 1. Disconnect the spark plug leads from the plugs and ground each lead to the powerhead. 2. Connect a liming light to the powerhead. 3. Place the remote shill lever in the NEUTRAL position. 4. loosen the locknut on the maximum advance screw. Hold the throllle lever in the all position until the maximum advance screw contacts the stop. 5. Crank the powerhead with the starter motor and at the same time adjust the maximum advance screw un!il the timing pointer is aligned in the timing mark specified in the ''Tune-Up Specifications· chart. 6. Tighten the locknut on the maximum advance screw to hold the adjustment. 7. Remove the timing light. CARBURETOR SYNCHRONIZATION t See Figure 96 1. Position the throttle lever idle stop screw against the idle stop. Measure the distance between the throllle arm barrel and the cam barrel. The measurement from center to center should be 5-"!132 in. (137.32mm). lf necessary, adjust the link rod for the correct measurement. 2. loosen the six carburetor synchronizing screws. Position the throttle lever against the idle stop. Position the throllle roller to just make contact with the throttle cam. Adjust the idle slop screw to align the slash mark on the throttle cam with the center of the throllle roller. Tighten the idle slop screw locknut. Hold the throttle roller arm steady and tighten the six carburetor screws to hold the adjustment. 3. Move the throttle lever from idle to half throttle while rooking at the carburetor shutters. Be sure all carburetor shu!ters open and close simultaneously. Repeat this step if any carburetor shutter does not fully close or move at the same lime. Install the sound box cover and secure with screws. FULL THROTILE STOP • See Figure 97 1. Move the throllle lever to the wide open throttle position. 2. Loosen the locknut and adjust the full throttle slop screw to permit full throttle shuller opening at wide open throttle. Check to be sure the throttle shutter does not act as a throllle stop. 3. Use a feeler gauge and check the clearance between the roller and the throttle cam at wide open throll!e. This clearance should be 0.010-0.015in. (0.25-0.38mm). 4. Tighten the locknut to hold the adjustment. 5. Install and tighten the spark plugs. OIL PUMP • See Figure 98 1. Move the powerhead throttle lever until the idle stop screw makes contact with the idle stop. 2. Check the alignment mark on the oil pump lever (first shortest mark) is at igned with the casting mark on the oil pump body. 3. If the alignment mark is not properly aligned, disconnect the linkage rod from the oil pump lever. 4. Adjust the rod end to align the mark on the oil pump body with the mark on the lever. 5. Connect lhe rod end onto the oil pump lever. IDLE SPEED 1. Place the outboard in a test tank or the boat in a body of water. Shift the lower unit into FORWARD gear. 2. Connect a tachometer to the powerhead. 3. Start the powerhead and allow il ia warm to operating temperature. 4. Remove the cable barrel from the barrel retainer and loosen the locknut on the idle adjustment screw. 5. Adjust the idle to the proper speed, as listed in the "Tune-Up Specifications· chart. Tighten the locknut to hold the adjustment. 6, With the end of the throttle cable connected to the throttle lever, hold the throttle lever against the idle stop. 7. Adjust the throttle cable barrel to slip into the barrel retainer on the cable anchor bracket with a very light preload of throttle lever against the idle stop. Lock the barrel in place. ,. .An excessive preload on the throttle cable will cause difficulty when shifting gears. 8. The preload may be easi ty checked by placing a piece of paper between the idle stop screw and the idle stop and then withdrawing it. If the paper does not tear but drag is felt, the preload is correct Adjust the cable barrel, if necessary, to obtain the proper preload just described. 037361'16 Fig. 94 Hold the throttle arm against the throttle stop while cranking the engine with the starter motor 00736P17 Fig. 95 Make the advance liming adjustment by turning the maximum advance screw until the timing mark Is aligned aim barf.l 00736G10 Fig. 96 Position the throttle lever idle stop screw against the idle stop powerheads in the following order:set theliming pointer, set the throttle cam, setthe full throttle stop, adjust the oil pump linkage, set the ignltion liming, set the idle speed, adjustthe throttle position sensorand finally,test drivethe boat to insure proper full throttle speed. Water must circulate through the powerhead any time it is running to prevent damage to the water pump and possible powerhead overhealing. Neverrun the engine over 3000 RPM without an adequate load applied to the propeller. IGNITION TIMING Timing Pointer • See Figure 99 1. Removeallspark plugs. 2. Install a dial indicator into theNo. 1 (top cylinder starboard bank). spark plug opening 3. Slowly rotate the flywheel clockwise until the No. 1 piston is attopdead center (TDC). Set the dial indicator to ·o·. Slowly rotate the llywheel counterclockwise unlll Jhe dial indicator needle Is.. turn beyond the .4621n. (11.73 mm) mark. 4. Slowly rotate the flywheel back-clockwise-until the dial indicator is exactly at the .462 in. (11.73 mm) mark. Observe the liming pointer on the flywheel cover and the .462 ln. (11.73 mm} mark on the llywheel. 5. If the flywheel pointer is not exactly on the mark, loosen the pointer adjustment screws and align !he pointer with the .462 fn. (1 1.73 mm) mark. 6. nghten the pointer adjustment screws and remove the dial indicator lrom the No. 1 spark plug opening. Preliminary Timing Adjustments • See Figures 100 and 101 1. Measurethe length of the trigger link rod from the center line ofthe 90°bend to the edge ofthe locknut. MAINTENANCE 3-35 Fig. 97 Throttle linkage assembly with major components identified m1JIG11 150-200 HP Electronic Fuel Injection (EFI) Perform synchronizatiol'ioof the 15G-200hp EF1 :;::;: CAUTION 03136P74 Fig. 100 Disconnect the Black/White wire from the idle stabilization module 2. A dimension or 1Yta in.(17.Smm) is required lor proper timing adjuslment. 3. II the measurement is not as spocilied, disconnect the link rod and adjusl. 4. Disconnect the Black,/Whl!e wlre lead from the idle stabilization module at the bulle1 connector next to the module.Wrap tape around the wireend to prevent it from shorting out. 5. Disconnect the control unitharness connectorlor the ignition timing procedures. Idle Timing t See Figures 102 and 103 1. Disconnectthe spark plug leads from the plugs and ground each lead to the powerhead. 2. Connect a timing light to the powerhead. 3. Place theremote sh1fi lever in the NEUTRALposition. 4. Loosen the locknut on the Idletiming screw. 5. Move the throttle lever until the idle stop screw contactsthe idle stop. 6. Crank the powerhead withthestarter motor and al the same time rotate the idlelimingscrewuntillhe marks onthe timing decal align with the timing mark specified in the "Tune-Up Specifications· chart 7. Tighten the locknut on the idle timing screw. Fig. 99 Slowly rotate the flywheel back Fig. 98 Make adjustments on the link rod ctockwise--unlil lhe dial indicator is to align the mark on the oil pump lever exactly at the .462 in. (11.73 mm) mark and casting mark on the oil pump body Fig. 101 Adimension of 1V1e ln. (17.5mm) Is required for proper timing adjustment Ol7J6P2Z Fig. 102 Move the throttle until the idle stop screw just contacts the Idle stop Fig. 103 Location of the idle timing screw 3-36 MAINTENANCE Maximum Advance Timing • See Figures 104 and 105 1. Disconnect the spark plug leads !rom the plugs and ground each lead Iathe powerhead. ?. Connect a timing light to the powerhead. 3. Place the remote shill lever in the NEUTRAL position. 4. Loosen the locknut on the maximum advance screw. Hold the throttle lever in the all position unli! the maximum advance screw contacts the stop. 5. Crank the powerhead with the starter motor and at the same time adjust the maximum advance screw until the liming pointer is aligned in the timing mark specified in the "Tune-Up Specifications" chart. 6. Tighten the locknut on the maximum advance screw to hold the adjustment. 7. Remove the timing light. Detonation Control System • See Figure 106 This system is used on the 200hp model only. 1. Connect a liming and tachometer to the powerhead. 2. Start the powerhead and allow it to lv\lmp) Fig. 113 Maximum throttle adjustment -115, 135 and 150hp 1 •ihtoeie Atm 2-Stop 3-FA! Th10""' Slop Sctew .:. -Throme Shan Arm s • 0.010in. (0234 mm) Clearance 6-Stop on AMO.I"lua!Dr Sox 05193G20 0519JG21 Fig. 114 Maximum throttle adjustment -200 and 225hp WINTER STORAGE CHECKLIST Taking extra lime to store the boat properly at the end of each season will increase the chances of satisfactory service a! the next season. Rememoor. storage is the greatest enemy of an outboard motor. The unit should be run on a monthly basis. The boat steering and shifting mechanism should also be worked through complete cycles several times each month. If a small amount ol time is spent in such maintenance, the reward will be satisfactory performance, increased longevity and greatly reduced maintenance expenses. 3. Tighten the jam nut on the full throttle stop screw. 4. Check lor free play (roller lifts from cam) between the roller and cam at lull throttle to prevent the linkage from binding. Readjust the full throttle stop screw if necessary. THROTILE PLATE SCREW t See Figures 115 and 116 ** WARNING II is not recommended that the th-rottle plate screw be adjusted from the factory setting. However, should the throttle plate require adjustment, use the throttle plate stop screw to set the total throttle plate clearance as follows. 1. On the 200 and 225hp models, using suitable drills (so that the combined air gap lore and aft on the throttle plate equals a total of 0.149 in. (3.78 mm) the correct clearance is 0.149 in. (3.78 mm). 2. On the 135 and 150hp models. the clearance is 0.131 in. (0.7937 mm) using a #68 drill. 3. On lhe 1 15hp model close the throttle plate and turn the throttle plate screw in one turn. 1 · Throttle Plate Stop Screw 2·Throttle Plate Clearance -Set • 0.149 ln. (3.78 mm)0St!l3G23 Fig. 115 The throttle plate assembly on the 200 and 225hp models _ .. 1 •Throttle Plate Stop Screw 2•Throllle Plate Clearance 3•Model 150 and MCre.Mx Pre-lob Pte-l.h Pre·l•h P111 ·1.b Pte -.. 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'OI IIlermosw &pressu recontiOI Water-cooled 'Oi lflermostal &pressu reCOOOol Water-cooled '0/ lflermostal & p!esrure COOirOI Wata--cooled ¥1 thermoslal &pressu re COOirOI Water-cooled wl lllermoslal &p!eSSU re coouol Water--cooled wllllermoslal &p!eSSU reCOiliiOI Wata-o$t a1 &pressur e 00111101 Water- z -f m z )> z 0 m 011S'.lCU2 Model 2.5 3.0 33 5 8 99 15 20 3040 (2-cy1) 40(3-cyfj40 (4-cyll 50 60 75 90 100 liS 125 135 ISO 150XR6/ EFI 150 Pro Max ER 1 75 175EA 200 200EFI 200 Pro tl..ax EA 225 225 EFl 250 EFI 275 135 OFt0pt.naJ. 150 Dfl Optn-ax 200 DR O!l:rr.a.. 225 ::JFI Opt.max Spark Plug NGK Champion BPRSHS ·10 Rl87YC BPR'-oHS..tO IUTYC Bf>f'.&iS·10 lt..87VC BPlHS-10 l82'1' C,l81V BPJHS .:O l82YC. l81Y 8?8rlS-15 BP8HS·1S BPSI--S-15 BPSH-N·IO BP..-N-10 . BP&i·IHO BPSH-N·IO BPBH-N-10 BlH\'1·2 l78V BPSH-N-10 BPSH·N·10 BUHW·2 l78V BPSH-N -10 BPSH..N-10 BPaP-N-10 BPSH-N-10 BVSH BU8H 3USH BUSh . 6!;8H BUSH SU8H BUSH BL8H B?zaH-N-10 at. nee BPZ!l H-N·IO Ol77CC BPZ&-1-N-10 Ql77CC BUSH PZFR5f·'1 AC121.\VI PZFA5F·11 ACI2MC4 PZFA5F·I1 OC12G'!C PZFRY' ·11 OC12G'.'C Spark Plug Gap lnch(mm) 0040 (I 0) 004 0 (\01 0.040(1 0) 0040(101 0040(1OJ 0040(10\ 0040("OJ 0.060(1 5) 0.040 (1 0} 0040{1 01 0040(1 0) 0.040 (1 01 0040(1 01 Surface £feet (No gapl 0.040 (1 OJ 0040(1 OJ SurfaceElf eel (No gao) 0.040 (1 0) 004 0(1 0) 0040{10) 0040(10J SIJ:tace Elf«l (No gap) Surface EF.etl {Nil gap)Surface Effa; (NQ gap) Surtare Eff!!Ct (No ga.) Surface Effect (No ga;;l Surface Effect (No s<.Pl S.Jrtace E.ect {NC 30' BlOC :WBTOC 36' BlOC 2S'BTOC 2'"' BTOC 22'· 28' BlOC 22' ·26' BlOC 22'BTDC 3CI' BlOC 22'BTOC 22'BTOC :a' BlOC 20'13TOC 20" BTOC 20" 9TOC 2575 52>575 52$-575 WOT Idle Mixture Screw RPM Turns out 90().. 1000 E-chpIllsecondf¥0!:Ne S00. 1000 E-4 J.l14 10 1·3.'4 500().5500 (.1/410 1·3'4 500(). .. (.114 ..0 1·3'4 4751).52 50 1·;/2 1·1f.! '751).S250 1·3'4 475i).S250 1·112 47..5250 1-11810 1-3:8 1·1'410\..4 l-1'410 "·3'4 500().5500 to •-3'4 J.t!4 to 1-3•4 Hl4 to t-3!4 5000-5500 1-1/4 to 1·314 1-114 to t-31'4 50()0. 5600 1-114 to t-3/4 6200-S:.OO H/4 10 1·314 1-114 to 1-3'4 5000·5500 I· \14 to 1-l'. 5000-5500 1-114 :o 1-314 5000-5500 NIA (faced tell 5000 ·5600 NIA .5000-5600 NIA 50»-5750 NIA 5000-5750 !;5 "!1!&1 < $: )> z .. m z )> z 0 m w I .... 3-42 MAINTENANCE Maintenance Interval Chart First Every Every Off Component 1mth/10hrs 3mths/50hrs 6mths/100hrs Season 2.5 3 3.3 4 5 6 8 9.9 15 20 2530, 40 (2-ql.)40 (4-ql.)40, 50 (3-ql.)55, 60 (3-cyl.) 70,75,80,90 100, 115, 125 135, 150 XR4, Magnum II 175,200,225 115, 135, 150, 200, 225 OFI PreMix 3.0 (90} PreMix 3.0 (90} PreMix 3.0 (90) PreMix 6.6 (195} PreMix 6.6 (195} PreMix 6.5 (200} PreMix 6.5 (200} PreMix 6.5 (200} PreMix 6.5 (200} PreMix 7.6 (225} PreMix 8.8 (260} 1.5 (1 .5} 14.9 (440} 3.74 (3.54) 12.5 (370) 3.0 (2.8) 14.9 (440) 3.0 {2.8) 11.5{340)4.0 (3.78) 22.5 (665.3) 5.6 (5.3) 22.5 (665.3) 12 (11.4) 24.25 (717) 12 (11 .4) 21 (625} 12 (11.4) 24.25 (717) 12 (11.4} 22.5 (665.3} 0.375 (1 .4} 0.375 (1.4} 0.375 (1 .4} 0.66 (2.5} 0.66 (2.5} 3.2 (12} 3.2 (12} 3.2 (12} 6.6 (25} 6.6 (25} 6.6 (25} 6.6 (25) 6.6 (25) 6.6 (25) 6.6 {25} 6.6 (25) 6.6 (25} 6.6 (25) 6.6 (25} 6.6 (25} 6.6 (25} Boltsandn..Spar1< plugs Sllr1erMota' Brush Length Ignition lining Carbll'etorGear oil Pistons, cylinder and head Propeller Choke Fuel tank Fuel miner Fuel hoses Water pump Clutth lever Sllr1er rope Tilt Neullal start inter1ock sMith Zinc Anodes A-AdJust C..Ciean 1-lnspect and Clean, Adjust, lubfic3te or Replace L-Lublicate R-Replace T-Tighten T I C&A R l I I L Model T C&A . I C&A R Oe.cart>on l I II I L&A L I A I I Injection Oil Lower Unit Quart (Liter) Oz. (ml) C&A Fuel Tank Gal. (liter) T C&A C&A C&AR I l I I L I 05193C01 FUEl AND COMBUSnON 4-2 FUEL 4-2 OCTANE RATING 4-2 VAPOR PRESSURE 4·2 ALCOHOL -BLENDED FUELS 4-2 HIGH ALTITUDE OPERATION 4-2 RECOMMENDATIONS 4-2 COMBUSTION 4-2 CARBURffiD FUEL SYSTEM 4·3 CARBURETION 4-3 BASIC FUNCTIONS 4·3 FUEL & AIR METERING 4·4 CARBURETOR CIRCUITS 4·4 FUEL PUMP 4-5 1ROUBLESHOOTING lHE FUEL SYSTEM 4-6 COMMON PROBLEMS 4-6 COMBUSTION RELATED PISTON FAILURES 4·7 2.5. 3 AND 3.3 HP 4-8 REMOVAL & INSTALLATION 4·8 DISASSEMBLY 4-8 CLEANING & INSPECTION 4·10 ASSEMBLY 4-10 4AN05HP 4.:11 REMOVAL & INSTALLATION 4·11 DISASSEMBLY 4-12 CLEANING & INSPECTION 4-13 ASSEMBLY 4-13 5. 8, 9.9, 10 AND IS HP 4-14 REMOVAL & INSTALLAl'ION 4-14 DISASSEMBLY 4-15 CLEANING & INSPECTION 4-17 ASSEMBLY 4·19 20 AND 25 HP 4-20 REMOVAL & INSTALLATION 4-20 DISASSEMBLY 4-20 CLEANING & INSPECTION 4·21 ASSEMBLY 4-22 30 AND 40 HP (2-CYUNOER) 4-23 REMOVAL & INSTALLATION 4-23 DISASSEMBLY 4-24 CLEANING & INSPECTION 4-25 ASSEMBLY 4-25 40-125 HP 4-26 REMOVAL & INSTALLATION 4-27 DISASSEMBLY 4-28 CLEANING & INSPECTION 4-30 ASSEMBLY 4-31 1990 135-200 HP 4-33 REMOVAL & INSTALLATION 4·33 DISASSEMBLY 4·35 CLEANING & INSPECTION 4-35 ASSEMBLY 4·36 199HXl 135-200 HP 4-37 REMOVAL & INSTALLATION 4-37 DISASSEMBLY 4·38 CLEANING & INSPECTION 4-40 ASSEMBLY 4-40 1991-00 275 HP 4·41 REMOVAL & INSTALLATION 4-42 DISASSEMBLY 4-43 CLEANING & INSPECTION 4-44 ASSEMBLY 4-44 FUEl PUMP 4-45 TESTING 4-45 REMOVAL & INSTALLATION 4-47 'f OVERHAUL 4-48 FUEL UNES 4-49 ELECTRONIC FUEl INJECTION (Efl) 4-50 DESCRIPTION AND OPERATION 4-50 FUEL INJECTION BASICS 4-50 MERCURY ELECTRONIC FUEL INJECTION 4·50 TROUBLESHOOTING ELECTRONIC FUEL INJECTION 4-53 FUEl INJECTORS 4-54 TESTING 4-54 REMOVAL & INSTALLATION 4·56 CLEANING & INSPECTION 4-60 COOLANT TEMPERATURE SENSOR 4-60 TESTING 4·60 REMOVAL & INSTALLATION 4·60 AIR TEMPERATURE SENSOR 4-60 TESTING 4-60 REMOVAL & INSTALLATION 4·60 MECHANICAL FUEL PUMP 4·61 TESTING 4-61 REMOVAL& INSTALLATION 4-61 ELECTRIC FUEL PUMP 4-61 TESTING 4-61 REMOVAL & INSTALLATION 4-62 VAPOR SEPARATOR 4-62 REMOVAL & INSTALLATION 4-62 CLEANING & INSPECTION 4-63 FUEL PRESSURE REGULATOR 4-64 REMOVAL & INSTALLATION 4-64 lHROffiE POSITION SENSOR 4·65 TESTING 4·65 REMOVAL & INSTALLATION 4-65 ADJUSTMENT 4-65 DETONATION SENSOR AND MODULE 4-66 TESTING 4-66 OPTIMAX DIRECT FUEL INJECTION (DFI) 4-66 DESCRIPTION AND OPERATION 4-66 OPTIMAX COMPONENTS 4-68 TROUBLESHOOTING lHEOPTIMAX FUa INJECTIONSYSTEM 4·69 WllHOUT THE DIGITAL DIAGNOSTIC TERMINAL (DDT) 4·69 WITH THE DIGITAL DIAGNOSTIC TERMINAL (DDT) 4-70 AJR COMPRESSOR 4-70 TESTING 4-70 REMOVAL & INSTALLATION 4-70 AJR PRESSURE REGULATOR 4-72 REMOVAL & INSTALLATION 4-72 AIR TEMPERATURE SENSOR 4-72 TESTING 4-72 REMOVAL & INSTALLATION 4-72 CRANKSHAFT POSITION SENSOR (CPS) 4-72 TESTING 4-72 REMOVAL & INSTALLATION 4-72 lHROTILE POSITION SENSOR (TPS) 4-73 TESTING 4·73 REMOVAL & INSTALLATION 4-73 DIRECT INJECTOR 4-73 TESTING 4-73 REMOVAL & INSTALLATION 4-73 CLEANING & INSPECTION 4-74 ELECTRONIC CONTROL MODULE (t:CM) 4-74 REMOVAL & INSTALLATION 4-7 4 FUEl INJECTOR 4-74 TESTING 4-74 REMOVAL & INSTALLATION 4-74 CLEANING & INSPECTION 4·74 FUEL PRESSURE REGULATOR 4-75 REMOVAL & INSTALLATION 4-75 CLEANING & INSPECTION 4·75 FUEL PUMP 4-75 TESTING 4-75 FUEL RAIL 4·76 REMOVAL & INSTALLATION 4-76 CLEANING & INSPECTION 4-76 MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR 4-76 TESTING 4-76 REMOVAL & INSTALLATION 4-76 SHIFT INTERRUPT SWITCH 4·76 TESTING 4·76 REMOVAL & INSTALLATION 4-76 THROTILE PLATE ASSEMBLY 4-IT REMOVAL & INSTALLATION 4-IT TRACKER VALVE 4-IT REMOVAL & INSTALLATION 4-77 VAPOR SEPARATOR 4-77 REMOVAL & INSTALLATION 4-77 DISASSEMBLY 4-77 CLEANING & INSPECTION 4-77 ASSEMBLY 4-78 WATER TEMPERATURESENSOR 4-78 TESTING H8 REMOVAL & INSTALLATION 4-78 SPECIFICATIONS CHART WME CARBURETOR SPECIFICATIONS 4-26 4-2 FUEL SYSTEM FUEL AND COMBUSTION Fuel Fuel recommendations have become more complex as the chemistry ofmodern gasoline changes. The major driving Ioree behind the changes in gasoline chemistry is the search for additives to replace lead as an octane booster and lubricant. These new 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 ol combustion stability, making a fuel's octane rating less meaningful. In the 1960's and 1970's, leaded luel was common. The lead served two functions. First, it served as an octane booster (combustion stabilizer) and second, in 4stroke engines, it served as a valve seat lubricant. For 2-stroke engines, the primary benelit ol lead was to serve as a combustion stabilizer. lead served very well lor this purpose, even in high heat applications. Today, 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 engines, most do not perform nearly as well as lead did, even though the octane rating of the fuel is the same. ..OCTANE RATING •.· Afuel'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 lor a parlicufar application. For example, in an engine, we want the luel la ignite when the spark plug tires and not before, even under high pressure and temperatures. Once the luel is ignited, it must burn slowly and smoothly, even though heat and pressure are building up while the burn occurs. The unburned luel should be ignited by the traveling flame front, not by some other source ol ignition, such as carbon deposits or the heat !rom the expanding gasses. A fuels octane rating is known as a measurement of the luel's anti-knock properties (ability to burn without exploding). Usuallya fuel with a higher octane rating can be subjected to a more severe combustion environment belore spontaneous or abnormal combustion occurs. To understand how two gasoline samples can be dillerent, even though they have the same octane rating, we need to know how octane rating is determined. The American Society ol Testing and Materials (ASTM) has developed a universal method of determining the octane rating 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 R+M/2 method. This number is the average ol the research octane reading and the motor octane rating. • The Research Octane Rating is ameasureof a luel'santi-knock properties under a light load or part throttle conditions. During this test, combustion heat is easily dissipated. • The Motor Octane Rating Is ameasure ol afuel's anti-knock properties under a heavy load or lull throttle conditions, when heat buildup is at maximum. Because a 2-stroke engine has a power stroke every revolution, with heat buildup every revolution, it tends to respond more to the motor octane rating of the fuel than the research octane rating. Therefore, in an outboard motor. the motor octane rating of the fuel is the best indication of how it will perform. VAPOR PRESSURE Fuel vapor pressure is a measure of how easily a luel 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 ol a fuel sample but can cause vapor lock (bubbles in the fuel line) on a very hot day. If you 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 cleanertoprevent ring sticking due to excessive varnish buildup. ALCOHOL-BLENDED FUELS When the Environmental Protection Agency mandated a phase-oui of ihe leaded fuels in January of 1986, fuel suppliers needed an additive to improve the octane rating ol their fuels. Although there are multiple methods currently employed. the addition of alcohol to gasoline seems to be favored because ol its favorable results and lowcost. Two types ol alcohol are used in fuel today as octane boosters, methanol (wood alcohol) or ethanol (grain alcohol). When used as a luel additive, alcohol tends to raise the research octane of the fuel. so these additives will have limited benelit in an outboard motor. There are, however, some special considerations due to the elfects of alcohol in fuel. • Since alcohol contains oxygen, it replaces gasoline without oxygen content and tends to cause the air/fuel mixture to bocome leaner. • On older outboards, the leaching affect of alcohol will, in time, cause fuel lines and plastic components to become brittle to the point or cracking. Unless replaced, these cracked lines could leak fuel. increasing the potential for hazardous situations. • When alcohol blended luels become contaminated with water, the water combineswith the alcohol then settles to the bottom of the tank. This leaves the gasoline (and the oil for models using premix} on a top layer. ,..Modern o.utboard fuel lines and plastic fuel system components have been specially formulated to resist alcohol leaching effects. 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-jelting for high altitude does not restore lost power. it simply corrects the air-fuel ratio lor 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 air/luei ratio wi II not be achieved 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. Most Mercury/Mariner engines need only 87 octane or Jess. An 89 octane rating generally means middle grade unleaded. Premium unleaded is more stable under severe conditions but also produces more combustion products. Therefore. when using premium unleaded, more frequent de-carboning is necessary. Combustion • See Figure 1 Unlike a 4-stroke engine, a 2-slroke engine has a power stroke every revolution of the crankshaft. Therefore. the 2-stroke engine has twice as many power strokes for any given RPM. If the displacement of the two types of engines is identical, then the 2-stroke engine has to dissipate twice as much heat as the 4-stroke engine. In such a high heat environment, the luel must be very stable to avoid detonation. II any parameters affecting combustion change suddenly (the engine runs lean for example), uncontrolled heat buildup will occurs very rapidly. The combustion process is affected by several interrelated factors. This means that when one factor is changed, the other factors also must be changed to maintain the same controlled burn and level of combustion stability. • Compression-determines the level ol heat buildup in the cylfnder when the air-fuel mixture is compressed. As compression increases, so does the potential for heat buildup • Ignition Timing-determines when thegasses will startto expand in relation to the motion of the piston. If the ignition timing is too advanced. gasses will be ignited and begin to expand too soon, such as they would during preignition. The motion of the piston opposes the expansion of the gasses. resulting in extremely high combustion chamber pressures and heat. If the ignition timing is retarded, the gases are ignited later in relation to piston position. This means that the piston has already traveled back down the bore toward the bottom of the cylinder, resulting in less usable power. • Fuel Mixture-determines how efficient the burn will be. A rich mixture burns slowef than a lean one. If the mixture is too lean, it can1 become explosive. The slower the burn, the cooter the combustion chamber, because pressure buildup is gradual. • Fuel Quality (Octane Rating)-determines how much heat is necessary to ignite the mixture. Once the burn is in progress, heat is on the rise. The unburned poor quality fuel is ignited all at once by the rising heat instead of burning gradually as a llame front of the burn passing by. This action results in detonation (pinging). There are two types of abnormal combustion-preignition and detonation. • Preignition-occurs when the air-fuel mixture is ignited by some other incandescent source other than the correctly timed spark from the spark plug. Atomized fuel BASIC FUNCTIONS FUEL SYSTEM 4-3 • Detonation-occurs whenexcessive heal and or pressure ignites the air/fuel an engineover the edge toabnormal combustion, if any of I he fourbasicfactorspre mixtureratherthan the spark plug. Thebumbecomes explosive. viously discussed are already near thedanger point, for example. excessive carbon In general, anything!hatcan causeabnormalheat buildup can be enough topush buildup raises lhe compressionand retains healas glowing embers Fig. 1 Two-stroke engine operation F\t.. •nd from It• ctf.nlic.,• lO ,,_. e.t\Ju.tt pof'l u.e combutdon .ehemb4:r CARBURETED FUEL SYSTEM Carburetion Fuel Carburetor operating principles OCIOC18 Fig. 2 If you blow air across a straw inserted into a container olllquid, a pressure drop is created Inthe straw column. As theliquid In the column is expelled, an atomized mixture (air and liquid droplets) is created t SeeFigure 2 Traditional carburetor theoryolten involves anumber of laws and principles. The diagram Illustrates several carburetor basics. II you blow air across a straw inserted intoa container of liquid. a pressure drop iscreated In the straw column. As theliquid in the column is expelled, an atomized mixture (air and fuel droplets) Is created. Ina carburetor this is mostly air and a little luel. The actual ratio of air to fuel differs with engine conditions but is usually from 15 , parts air to one part fuel atoptimum cruise to as lft!le as 7parts air to onepart fuel at full choke. Using our example, whatillhe top of the container is covered and seated around the straw. what will happen? No llow. This is typical of a clogyed car buretor bowl venl Ifthebaseof the straw is clogged or restricted what will hap pen? No flow or low flow. This represents a clogged main jet. If the liquid in the glass Is lowered and you blow through the straw with the same Ioree what will happen?Not as much fuel will flow. A lean condition occurs. II the fuel level is raised and you blow again at the same velocity what happens? The resullisa richer mixture. 4-4 FUEL SYSTEM FUEL & AIR METERING The carburetor is merely a metering devicetor 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 parts air to 1 part fuel. Float Systems t See Figure 3 A small chamber in the carburetorserves as a luel reservoir. A floatvalve admits fuel into the reservoir to replace the fuel consumed by the engine. li the carburetor has more than one reservoir, lhe fuel level in each reservoir (chamber) is controlled by identical float systems. Fuel level in each chamber is extremely critical and must be maintained accurately. Accuracy is obtained through proper adjustment of the floats. This adjustment will provide a balanced metering of luel to each cylinder at all speeds. Following the fuel through its course, from the fuel tank to the combustion chamber ol the cylinder. will provide an appreciation of exactly what is taking place. In order to start the engine, the luel must be moved from the lank to the carburetor by a squeeze bulb installed in the fuel line. This action is necessary because the fuel pump does not have s..flicienl pressure to draw fuel from the tank during cranking before the engine starts. The fuel for some small horsepower units is gravity fed !rom a tank mounted at the rear of the powerhead. Even with the gravity feed method, a small fuel pump may be an integral part of the carburetor. After the engine starts, the fuel passes through the pump to the carburetor. All systems have some type of tiller installed somewhere in the line between thetank and the carburetor. Many units have a Iiiier as an integral part of the carburetor. At the carburetor, the fuel passes through the inlet passage to the needle and seat and then into the float chamber (reservoir). A !foal 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 lloat closes the inlet needle and the flow entering the chamber is cut off. When fuel leaves the chamberas the engine operates, the fuel level drops and the float lang allows the inlet needle to move off its seal and fuel once again enters the chamber. In this manner. a constant reservoir of fuel is maintained in the chamber to satisfythe demands of the engine at all speeds. A fuel chamber vent hole is located near the top of the carburetor body to permit atmospheric pressure to act against the fuel in each chamber. This pressure assures an adequate fuel supply to the various operating systems of the powerhead. Throttle Idle and slow speed Ol7041301 Fig. 3 Fuel flow through a venturi, showing principle and related parts controlling intake and outflow Air/Fuel Mixture t See Figure 4 A suction effect is created each time the piston moves upward in the cylinder. This suction draws air through the throat of the carburetor. A restriction in the throat, called a venturi, controls air velocity and has the eflect of reducing air pressure at this point. The dillerence in air pressures at the throat and in !he fuel chamber. causes the fuel to be pushed out of metering jets extending down Into the fuel chamber. When the fuel leaves the jets, it mixeswith the air passing through the venturi. This fuel/air Atmosphericair pressure ()f/U4GQ2 Fig. 4 Air flow principle of a modern carburetor mixture should then be in the proper proportion for burning in the cylinders for maximum engine performance. In order to obtain the proper air/fuel mixture for all engine speeds, some models have high and low speed jets. These jets have adjustable needle valves which are used to compensate for changing atmospheric conditions. In almost all cases,the high-speed circuit has fixed high-speed jets and arenot adjustable. A throttle valve conlfols the flow ofair/fuel mixture drawn into the combustion chambers. A cold powerhead requires a richer fuel mixture to start and during the brief period it is warming to normal operating temperature. A choke valve is placed ahead of the metering jets and venturi. As this valve begins to close. the volume of air intake is reduced, thus enriching the mixture entering the cylinders. When this choke valve is fully closed, a very rich fuel mixture is drawn into the cylinders. The throat of the carburetor is usually referred to as the barrel. Carburetors with single. double or lour barrels have individual metering jets, needle valves, throttle and choke plates for each barrel. Single and two barrel carburetors are fed by a single float and chamber. CARBURETOR CIRCUITS The following section illustrates the circuit functions and locations of a typical marine carburetor. Starting Circuit t See Figure 5 The choke plate is closed, creating a partial vacuum in the venturi. As the piston rises, negative pressure in the crankcase draws the rich air-fuel mixture from the float bowl into the venturi and on into the engine. Pilot outlet Pilot screw.....---By·pass holes " ··.::!;::-. Ma..airjet · ·:.,.:..... = Fig. 5 Carburetor starting circuit low Speed Circuit • See Figure 6 Zero-one-eighth throttle, when the pressure in the crankcase is lowered, the airluel mixture is discharged into the venturi through the pilot outlet because the throtlle FUEL SYSTEM 4-5 0365IC10 Fig. 18 Exploded drawing of the round bowl, single float carburetor, with integrated Keihin fuel pump. Major parts are identified Place all of the metal parts in a screen-type tray and dip them in carburetor cleaner until they appear completely clean-free of gum and varnish which accumulates from stale fuel. Biow the parts dry with compressed air. Blow out all of the passage.'lays in the carburetor with compressed air. Check all of parts and passageways to be sure they are clear and not clogged with any deposits. Never use a piece of wire or any type of pointed instrument to clean drilled passages or calibrated holes in a carburetor. Carefully inspect the casting lor cracks, stripped threads or plugs for any sign of leakage. Inspect the float hinge in the hinge pin area for wear and the float for any sign ol leakage. Examine the inlet needle lor wear. If there is any evidence of wear, the needle must be replaced. Always replace any worn or damaged parts. A carburetor service kit is available at modest cost from the local Mercury/Mariner dealer. The kit will contain all necessary parts to perform the usual carburetor overhaul. ASSEMBLY • See accompanying illustrations 1. Invert the carburetor and allow the float to rest on the needle valve. Measure the distance between the top ol the float and the mixing chamber housing. This distance should be 1f2 in. (13 mm). This dimension, with the carburetor inverted, places the lower surlace of the fioat parallel to the carburetor body. H the dimension is not within the limits listed, the needle valve must be replaced. 2. Carefully bend the float arm, as required, to obtain a satisfactory measurement. Install the float. 3. Slide the wire attached to the needle valve onto the float tab. 4. Guide the hinge pin through the float hinge. Lower the float and needle Step4 '{ 4-1 4 FUEL SYSTEM Step 5 Step 6 assembly down into the noat chamber ana guide the needle valve lnto the needle seat. Check to be sure the hinge pin Indexes Into the mounting posts. Secure the pin in place with the small,l'hillips screw. 5. Insert the rubbe?"seating ring into the groove In theiloat bawl. lnslaii lhe lloat bowl and secure it in place with the tour Phillips screws. 6. Place the check valves, one at a trme. in position on both sides o! the fuel pump body.Secure each valve with the attach'ng screw. 7. Assemble the fuel pump COI!llOnents onto lhe carburetorbOdy in the following order. the inner gasket, the innerdiaphragm, the pump bc-dy, the outer dia­phragm,the outer gasket and finallythe pump cover. Checkto be sure allthe parts are properlyaligned with the mounting holes. Secureit all in placewith the lour attachrng screws. 8. Install the oval air jel cover and lhe round bypass cover In their proper recesses. Place the top cover over them, no gasket Is used. Install and tighten the twoattaching screws. 9. Slide the spring over the pilot screw and then install the screw. Tighten lhe screw until it barely seats. Back the pilot screw out 1 Yz turns. Step 2 Step 5 Step 6 Step 7 6, 8, 9.9, 10 and 15 HP The 6. 8, 9.9, 10 and 15hp models are equipped with a Walbro 'WM" or "WMC" carburetor with lntegralluel pump. The WM and WMC carburetors can be Identified by the embossed letters on themounting tlange. REMOVAL & INSTALLATION t See accompanying illustrations 1. Using a pair or pliers, remove the Circlip securing the choke knob in place. 2. Remove the choke knob by pulling itstraight oul. Unsnap the idle wire from the primerbracket. Remove the two bolls securing the primer bracket to the carburetor. The primer bracket will come free with the bracket. Usinga pair or snips. cut the Sta-strap lrom the fuel hose to the carburetor. Pull the luel line lree olthe lilting. Remove the lwo carburetor mounting bolls and till the carburetor off the powerhead. Step 4 Step7 '( Step 11 Step 14 3. Remove the high speed Jet from the bottom of the carburetor. The jet also serves as a retaining boll for the fuel bowt. 4. Ult the fuel bowl off the carburetor. The primer system is attached to the bowl and therefore, will come with it UH out lhe fuel lloal 5. Back out the screw securing the hinge pin In place. Pull the hinge pin and then lilt the hinge out of the carburetor body. 6. Remove the inlet needle from its position under the hinge. Remove the carburetor bowl gasket from its recess. 7. Remove the two screws securing the mixing chamber cover to the carburelor body. Remove the cover and then the gasket B. Remove the five screws securing lhe fuel pump cover in place. Remove in order. the cover. gasket and then the fuel pump check valve diaphragm. ,..Make sure to count the number of turns as the low speed mixture screw is removed, as an aid during assembling to making a rough bench adjustment. 9. Back out and count the numbet ol turns requlreo to remove the low speed mixture SCiew. The spring will come wilh the screw. 10. Remove the lour screws securing the primer system cover tothe lloat bowl llange. Gently lift the cover and the primer diaphragm, gasket and spring will then be free, as shown. A seal is installed in lhe cover. 11. Remove the base plug from the underside of the lloat bowl !lange (primer system housing). Take care nol to lose lhe spring from the shaH ol the plug or the liny check ball. 12. Remove the washer. To Install: 13. Posll.ion a new carbl.lrelor gaskel onto the powerhead. Install the carburetor to the powe!head and secure it in place with the two nuts. 14. Connect !he fuel hOseand secure it wllh a new Sta-strap. Install the small primer bracket to lheside of lhe carburetor with the two bolts. 15. Snap the idle wiLe into place on the ratchet adjustment lever. 16. Position the choke knob In place lhrough the opening In the lower cowling. lnst.aU the Circlip securing the choke knob. 17. Mount the outboard unit in atest lank, on a boat in a body of water or connect a flush attactlment to ttle lower unit FUEL SYSTEM 4-15 Ol\741'61 Step '16 DISASSEMBLY • See accompanying illustrations 1. Using a parr of pliers. remove the Clrctlp securing the choke knob in place. 2. Remove lhe choke knob by pulling il straight out Unsnap the idle wire from the primer bracket. Remove lhe two bolts securing the primer bracket to the carburetor. The primer bracket will come free with the bracket. 3. Using a pair or snips. cul the Sta-strap from !he fuel hose to the carburetor. Step 3 :t 4-16 FUEL SYSTEM Step 6 Step 8 Step 11 Pull the luel line free of lhe frtling. Remove the two carburetor mounting bolts and lilt the carburetor oil the powerhead. 4. Remove lhehigh speed fel lrom the boHom ol lhe carburetor. The jet also seNes as a retaining boll lor the fuel bowl. Lift out lhe fuel lloat. 5. Lilt the luel bowl ofl lhe carburetor ..The primer system Is attached to the bowl and therefore, will come with II. 6. Back oul the screw securing the hinge pin In place. Pull the hinge pin, and then lilt the hinge out ol lhe carburetor body. 7. Remove the inlet needle lrom its position under the hinge. Remove the carburetor bowl gasket lrom its recess. Step 7 Step 12 Low speedmixture 8. Remove the two screws securing the mixmg chamber cover to the carburetor body. Remove the cover. and then lhe gasket. 9. Remove the five screws securing the luel pump cover in piace.Remove in order, the cover, gasket, and then the fuel pump check varve and diaphragm. ..count the number of turns as the low speed mixture screw Is removed, as an aid during assembling to making a rough bench adjustment. 10. Back out and count the number ol turns required to remove the tow speed mixture screw. The spring will come wilh ttte screw. 11. Remove the lour screws securing the primer system cover to the lloat bowl '( FUEL SYSTEM 4-1 7 Good Worn Fig. 19 All rubber and plastic parts must be removed before other carburetor parts are placed in a basket to be submerged in carburetor cleaner 035141'54 Ag. 20 Comparison of a worn and new needle and seat arrangement. The worn needle would have to be replaced for full carburetor efficiency Ag. 21 Exploded drawing of the integral fuel pump to show arrangement of dia· phragm and gasket ffange. Genlly lillthe cover and the primer diaphragm, gasket, and spring will then be free, as shown. Aseal is Installed in lhe cover. 12. Remove the base plug from the undersideol the lloat bowl flange (primer system housing). Takecare not to lose the spring Irom the sl)all ol the plug or the tiny check ball. Remove the washer. CLEANING & INSPECTION t See Figures 19 thru 24 Never dip rubber parts, plastic parts, diaphragms or pump plungers in carburetor cleaner, because they tend to absorb liquid and expand. These parts should be cleaned only in solvent and then blown drywith compressed air immediately Seal Primer I Primersystemhousing .. Check ball ..-Spring0-+--Gasket ..PlugCI3574G12 Fig. 22 Exploded drawing of t.he primer system with major parts Identified Place all of the metal parts in a screen-type tray and dip them in carburetor cleaner until they appear completely clean-tree of gum and varnish which accumulates lrom s!ale fuel. Blow the parts dry with compressed air. Blow out all of ll1e passageways in the carburetor with compressed air. Check all ol partsand passageways to be sure they are clear and not clogged with any deposits. Never use apiece of wire or any type of pointed instrument to clean drilled passages or calibraled holes in a carburetor Carefully Inspect lhe casting for cracks, stripped threads or plugs for any sign of leakage. Inspect the float hinge in the hinge pin area lor wear and the floal for any sign of leakage. Examine the inlet needle for wear. If there is any evidence of wear, the needle must be replaced. Always replaceany worn or damaged parts. A carburetorservice kit is available al modest cost lrom the local Mercury/Manner dealer. The kil will coolaln all necessary parts to perform the usual carburetor overhaul. roller "') Pilot L Float bowl Ag. 23 Exploded view of a typical early model "WM" carburetor with Integral fuel pump. Major parts are Identified 4-18 FUEL SYSTEM Carburetor Assembly 1 -Retainer, Fuel bowl 2-Gasket 3-High Soeee Jet4-Fuel &owl 5-Gaskel 6-Float 7-Screw 8-Float ?m 9 -10-Inlet Needle Float Hinge 11 -Carburetor Body 12-Pump Che:.t Valve Diaphragm 13-Gasket14-Fuel Pump :over 15-Screw IS-Screw 11 -Throroe Shaft 18-Screw 19-Sonr.<; 20 · Throne Sn.l!ler Plate 51 -Retaining Pins 52 -Cam Blcx;k 53-Cam Stock Retaining Screw 54 -Air Intake Cover 55 Access Plug 56 -Screw (2) to Diaphragm 62 -Diaphragm 63 • Fuel Pump Cover64-Lock Washer (5) 65 • Screw (5), Tighten Evenly and Securely 66-Idle Timing AdJUStment Screw THROTTLE SHAFT COMPONENTS (MODELS with IDLE SPEED SCREW) 67 -Throttle Shall 68 • Throttle Cam 69 • Idle Speed Screw/Spring Fig. 24 Exploded view of a typical late model "WMC" carburetor with Integral fuel pump. Major parts are Identified ASSEMBLY • See accompanying illustrations 1. Dro.. the tiny check ball and then the Hille spring into the cavity ol the primer system, hous1ng. Set a new washer In place on the housing. Thread the plug into place and lighten il securely. 2. Tu.. the carburetor body over and set the spring in place in the primer housing. 3. Posll..on a ..ew gasket In place on the housing. Sel lhe primer diaphragm on top ol lhe spnng w1lh the holes In the diaphragm for the mounting screws roughly aligned with the holes in the primer housing.4. Slip the seal over the Up on the cover and compress thesprino wtlh the prifllCI syslemcoverallowing !he shafi ol lhe primer diaphragm to pass up through thehole in the seal and the hoiesin the diaphragm toalign perlcdly with the holes In the houslno. 5. Secure the cover In place with the lour attaching screws and lock-washers.6. Tighten the screws securely. Slide the spring onto the shall ol lhe low speed mixture screw. Thread the screw the carburetor housing and seat It lighlly. Step 11 Step 14 Step 16 FUEL SYSTEM 4-1 9 ... Never over-tighten the screw, because such action would damage the tip. 8. From the lightly seated position, backthe screw out the same number ol turns recorded during disassembly, li the number ol turns was lost. back the screw out 1V.. turns as a preliminary bench adjustment. This adjustment will allow the powerhead to be started.9. Place the fuel pump check valve diaphragm onto lhe carburetor body with the holes lor the mounting screws aligned with the holes In the body. Position a new gasket on top ol the diaphragm with the mounting holes aligned. 10. Place the fuel pump cover onto the carburetor booy and secure it with the live attaching and lockwashers. Tighten the screws securely.1t. a new gasket In placeon the mixing chamber. Install the mixing chamber cover onto the carburetor and secure it with the two SCfews. Tighten the screws securely.12. Posilion a new carburetor bowl gasket into place on the carburetor body. Slide the infet needle into its hole fn the body.13. Slide!he hinge pin through the hinge. Next. install the hinge and secure illn place with the screw. Tighten the screw snugly. Step 13 Step 17 4-20 FUEL SYSTEM ... Check to be sure the hinge will move without binding. 14, Slide the float down over the shalt and onto the hinge. 15. Check !he float level. Wilh the carburetor in the position shown, the distance from the lower edge of the float and the top of the retainer, should be 1 in. (25.4mm). If necessary, adjust the float level by ever so carefully bending the hinge Slightly. Just a "whisker" of change in the hinge will move the float. 16. Cover the float with the lloat bowl and primer system housing. 17. Slide a new gasket onto the high speed jel. tnstall the high speed jet. This jet also secures the bowl and primer system to the carburetor body. 20 and 25 HP REMOVAL & INSTALLATION t See accompanying illustrations 1. Using a pair of pliers, remove the circlip securing the choke knob in place. 2. Remove the choke knob by pulling it straight out. Unsnap the idle wire from the primer bracket. Remove the two bolts securing the primer bracket to the carburetor. The primer bracket will come free wilh the bracket Using a pair or snips, cut the sta-strap lrom the :Joel hose to the carburetor. Pull the fuel line free of the fitting. Remove the two carburetor mounting bolls and lilt the carburetor off the powerhead. To install: 3. Position a new carburetor gasket onto the powerhead. Install the carburetor to the powerhead and secure it in place with the two nuts. 4. Connect the fuel hose and secure it with a new sta-strap. 5. Install the small primer bracket to the side of the carburetor with the two bolts. Snap the idle wire into place on the ratchet adjustment lever. Step 1 Step 2 Step 3 6. Position the choke knob in place through the opening in the lower cowling. Install the C irclip securing the choke knob. DISASSEMBLY t See accompanying illustrations 1. Remove the high speed jet lrom the bottom of the carburetor. The jet also serves as a retaining bolt lor the fuel bowl. 2. Lilt the fuel bowl off the carburetor. The primer system is attached to the bowl and therefore. will come with it. lilt out the fuel float Step 1 Step 2 FUEL SYSTEM 4-21 Step 3 Step 9 3. Backout the screwsecuring the hingepin in place. Pull the hinge pin. andthen lilt the hinge ou1 ol the caJburetor body. 4. Remove the inlet needle fromits position underthe hinge. Remove the caJburelor bowl gasket from itsrecess. 5. Remove the two screws securing the mixing chamber cover to the carburetor body. Remove the cover, and then the gasket. 6. Remove the live screws securing the fuel pump cover in place. Remove in order, the cover, gasket, and then the fuel pump check valvediaphragm. ,..Count the number of turns as the tow speed mixture screwis removed, as an aid during assembling to makingarough bench adjustment. 7. Back ou1 and countthe number or turns required to remove thetow speed mixture SCfew. The spring will come with the screw. 8. Remove the lour screws securingthe primer system covertothe Hoal bowl rrange. Gentry lift the cover and the pnmer diaphragm, gasket, and spring will then befree, asshown. Aseal is installed inthe cover. 9. Remove the base plug !rom the underside ol the Ileal bowl !lange (primer system housing). Makesure not to lose the spring from the shaft or the plug or the tiny check tlall. Remove the washer. Step 5 Step 8 CLEANING & INSPECTION • See Figures 25, 26 and27 ,..Never dip rubber parts, plastic parts, diaphragms, or pump plungers In carburetor cleaner. These parts should be cleaned in solvent only, and then blown dry with compressed air. Fig. 25 All rubber and plasticparts must be removed before other carburetor parts are placed In a basket to be submerged Incarburetor cleaner 4-22 FUEL SYSTEM Accelera or--........ rotler ') ..Mtxmg S . Pilot vseat Main nozzle valveMain jetFloat -""'---.,!iingepon Floatbowl 04704Stl Fig. 26 Exploded)l_iew of a Walbro "WM" carburetor with integral fuel pump ...· Good Worn ..741'54 Fig. 27 line drawing to compare a worn and new needle and seat arrangement. The worn needle would have to be replaced for full carburetor efficiency 1. Place all the metal parts in a screen-type trayand dip them in carburetor cleaner until they appear completely clean-free ofgum and varnish which accumulates from stale fuel. Blowthe parts drywith compressed air. 2. Blow out all passageways in the castings with compressed air. Check all of the parts and passages to be sure Ihey are not clogged or contain any deposits. Never use a piece of wire orany type of pointed instrument to clean drilled passages or calibrated holes in a carburetor. 3. Carefully inspect the casting lor cracks, stripped threads, or plugs for any Step 1 Step 2 sign of leakage. Inspect the float hinge in the hinge pin area for wear and the IIoat for any sign of leakage. 4. Examine the inlet needle for wear and if there is any evidence of wear. the inlet needle must be replaced. 5. Always replace any and all worn parts. ,.A carburetor service kit is available at modest cost from the local marine dealer. The kit will contain all necessary parts to perform the usual carburetor overhaul wortc. ASSEMBLY • See accompanying illustrations 1. Drop the tiny check ball, and then the lillie spring into thecavity of the primer system housing. Set a new washer in place on the housing. Thread the plug into place and lighten it securely. 2. Turn the carburetor body over and set the spring in place in the primer housing. Next, position a new gasket in place on the housing. Set the primer diaphragm on top of the spring with the holes in the diaphragm for the mounting screws roughly aligned with the holes in the primer housing. Slip the seal over the lip on the cover 3. Now, compress the spring with the primer system cover allowing the shall of the primer diaphragm to pass up through the hole in the seal and the holes in the diaphragm to align perfectly with the holes in the housing. Secure the cover in place with the four attaching screws and lockwashers. Tighten the screws securely. 4. Slide the spring onto the shaft ol the low speed mixture screw. Thread the screw into the carburetor housing and seat it lightly. Never tighten the screw, because such action would damage the tip. From the lightly seated position. back the screw out the same number ot turns recorded during disassembly. li the number of turns was lost, backthe screw oul 1'14 turns as a preliminary bench adjustment. This adjustment will allowthe powerhead to be started. 5. Place the fuel pump check valve diaphragm onto the carburetor body with the holes for the mounting screws aligned with the holes in the body. Position a new gasket on top ot the diaphragm with the mounting holes aligned. 6. Placethe fuel pump cover onto the carburetor body and secure itwith the five attaching screwsand lockwashers. Tighten the screws securely. 7. Position a new gasket in place on the mixing chamber. Install the mixing chambercover onto the carburetor and secure it with the two screws. Tighten the screws securely. 8. Position a new carburetor bowl gasket into place on the carburetor body. Slide the inlet needle into its hole in the body. 9. Slide the hinge pin through !he hinge. Next. install the hinge and secure it in place with the screw. Tighten the screw snug.10. Check to be sure the hinge will move without binding.11. Slidethefloatdown over the shaftand onto the hinge.12. Check the lloat level asshown in the accompanying illustration. With the carburetor in the position shown, the distance from the lower edge of the float and the lop of the retainer, should be 1 inch (25.4mm}. If necessary, adjust the lloat level by very carefully bending the hinge slightly. The slightest movement of the hinge will move the float. 13. Cover the lloat with the float bowl and primer system housing. 14. Slide a newgasket onto the high speed jet. Install the high speed jet. This jet also secures the bowl and primer system to the carburetor body. 00514P50 03574G12 Step 3 '( Step 7 Step 11 Step 13 30 and 40 HP (2-Cylinder) Several different versions of the Walbro "WME" carburetor are used. The units are almost identical except for the main jet size REMOVAL & INSTALLATION • See accompanying Illustrations 1. Remove the battery leads lrom the battery terminals. Pull outward on the starboard side of the front shield. O..Gl4 Step 3 Step 4 FUEL SYSTEM 4-23 Step 8 Step 14 2. Remove the spring from the latch and open the cowlings. 3. Remove these screws prior to lilting off the air silencer from the carburetor. 4. Remove the air silencer. 5. Take time to identify each carburetor to ensure each will be installed back in its original position, because each carburetor is different. 6. Disconnect the throttle linkage from each carburetor. 7. Disconnect the fuel line from the engine then remove the hose clamps on each fuel line to each carburetor. Remove the luel llne from each carburetor. 8. Remove lhe attaching nuls securing each carburetor to the intake manifold. 9. Remove each carburetor from the powerhead. Step 6 4-24 FUEL SYSTEM Step 11 Step 12 To install: 10. Position new gaskets in place on the intake manifold. Install each carburetor onto the manifold in tge same position from which itwas removed. Each carburetor should have been idenl1fied as instructed during the removal procedures. 11. As appropriate, apply sealant toscrews or plugs as an anti-tampering me1hod.12. Secure the carburetors in place with the retaining nuts. Tighten the nuts allernately and evenly to a torque value of 1DO inch lbs. (11.3 Nm). 13. Connect all ofthe fuel tines to the carburetors and tighten the clamps securely. Connect the luel line from the fuel tank. Activate the ruet line squeeze bulb severat times and check the carburetors and fuel linesfor leaks. Connecllhe throttle linkage to and between the carburetors. Connect the battery leads to the baHery. DISASSEMBLY • See accompanying illustrations .-This carburetor does not have a traditional choke system. This enrichener system provides the engine with an extra fuel charge for ease of starting a cold engine. Step 4 Step 5 Step 13 ** WARNING Notice the application of red sealant on certain adjustment screws or plugs. This sealant was applied at the factory and is the manufacturer's method of instructing anyone servicing the carburetor not to disturb the screw or plug. The sealant is not affected by carburetor cleaner and should remain in place on the plug or sc rew andthe carburetor lor theentireuseful life of the carburet or. 1. Back out the idle mixture screw. .-It servicing a 3-Cylinder powerhead, remove the bowl vent jet located next to the idle mixture screw. ThJs jet is identical on all three carburetors. The 4-Cylinder powerheads are not equipped with this jet. 2. Remove the Phillips head screws and captive lockwashers and then remove the mixing chamber cover and gasket. 3. Remove the Phillips head screws with captive lockwashers from the float bowl. Lilt off the fuel bowl. Remove and discard thegasket. Cl3654P55 Step 6 4. Removethe stem gaske! from theccotcr of the fuel bowl. SUpportthe lloal and at the same time pushthe float hinge pin free of themounting posts. 5. Carefully lilttheHoat withtheInlet needleattached from the needle seaL Detach the inlet needle from the float. The needleseat is not removable on this carburetor. 6. Remove the main jet plug and gasket from the exterior wall of the float bowl. This plug provides access lor a screwdriver to be Inserted Into the opening and allows femoval of the main jet from lhe side of tho center turret. This design facilitateschanging the size of the main jet, without removal of the carburetor from the powerhead. Main jet sizes must be changed when operating the powerhead at elevalions higher than 2.500 feetabove sea level. -Further disassembly of the carburetor Is not necessary in order to clean it properly. CLEANING & INSPECTION • See Figures 28, 29 and 30 Never dip rubber parts. plastic parts. diaphragms or pump plungers in carburetor cleaner, because they tend to absorb liquid and expand. These parts should be cleaned only in solvent and then blown dry with compressed air immediately. Place all of the metal parts In a screen-type tray and dip them in carburetor cleaner until they appear cslnpletely clean-free ol gum and varnish which accumulates from stale fuel. Blow theparts dry with compressed air. Blow out all of!he passageways in the carburetor with compressedair. Checl< all or parts and passageways to besurethey ase clearand no! clogged with any deposits. Never useaptece ol wireor any type of pointedinstrument to ciean drilled pas· sagesorcalibrated holes in a carburetor. Carefully inspect ihe casling lor cracks, stripped threads or plugs lor any sign of .. Fig. 28 Never use a piece of wire or anytype of pointed instrument to clean drilled passages or calibrated holes in a carburetor, partie· ularly those in the mixing chamber 03G511'51 Fig. 29 Inspect the taper of the inlet needle and the idle mixture FUEL SYSTEM Thtollle shall ·Nol on all caros 4-25 4Xiiii>.C1S Fig. 3D Exploded drawing of Walbro "WME" carburetor, with major parts identified leale jet securely. lnstall lhe gasket and main jel plug in the exterior wall of the lloal bowl and tighlen tre plug securely. 7. Wllh the carburetor still inverted, position a new gasket onto the body. Place t..e fuel bowl in position and secure illn place with ll'e lour Phillips head screwsard capllvelockwasl'ers. 8. Posiliona new gasket over lhe mixing chamber. lns!all llie cover and secure it in place with theattaching 11ardvrcue. 9. Thread tile idle mixture sere" into the carbure:or until !he screw is lightlyseated. From lhis lightly seated position, bade the screw out approximately I..rums as a preliminary adjustment at this lime. 40-125 HP Two dUiereol Walbro carburetors are used on the 40-125hp Mercury/Mariner power heads. The Walbro WMA-wlth integral luel pump Installed on the 40hp model and the Walbro WME-wl!h separate fuel pump installed on all other powerheads. Several dilrerent versions ol the Walbro WME carburetor are used. Tire units are almost Identical excepl for lhe main jet slze and only the top two carburetors on a 4- carburelor lnslallation have adjustable Idle mixture screws. idenlilication tetters are stamped on lop of the carburetor mounting flange. Step 9 WME CARBURETOR SPECIFICATIONS MODEL CAlUIUIU:TOR MAIN BOWL LOCAnON VENTH.l'. NUMli R JET WM -2!-l Top Carburetor ..0 WME-28-2 Center Carburetor .052 .092 WM -28-S eo WM -22·2 /\ orB Center Carburetor .070 .090 Top Carburetor 60 WMt.:-8!>-2 Center Carbur ror .068 NONE Top Carbure or 70 2 Center arburet r .072 .094 Top Carburetor 76 l? Center CarbUTCtOr .068 .094 Top Carbur22 Fig.100 This special tool is needed to resize the Teflon ring prior to installation 3 Direct injector should nol leak down more than Y2PSi (35 kPa) in one minute. 4. If injector does not meel lhe above specifications. the injector must be replaced. REMOVAL & INSTALLATION • See Figures 99 and 100 ,..li the cylinder head is going to be replaced, removed the cup washers lrom each direct injector port by prying out with a flat lip screwdriver. Reinstall washers with retainers into the new cylinder head. Washers provide tension between direct injectors, cylinder head and luel rails. 1. Remove harness connector from the direct injectors. 2. Remove the direct injector (3 per cylinder head) from the cylinder head To install: 3. Use Teflon Ring Sizing Tool {91-851980...1) to compress new Teflon sealing rings prior to inslallation of injector into lhe cylinder head. 4. Carefully slide the fuel rail over the mounting studs and onto the direct injectors. :r 4-74 FUEL SYSTEM -..•..IOlOOilllll.(ll........ ·Do..;:fr« ·te . ....., ........ 051-Ring3 •Sprirlg4 •Cup 0519410 FUEL SYSTEM 4-75 Fuel Pump TESTING low Pressure Pump Output t See Figures 106, 107 and 108 ** WARNING After completing fuel pressure tests, reconnect and secure fuel out· let hose to fuel pump with full circle stainless clamps. 1. Remove the outlet fuel hose !rom the low pressure pump. Install ashort piece of hose (obtained locally) onto the pump outlet fitting. Install a Schrader valve Hilling ( 22-8496060 between the outlet fuel hose (removed !rom the pump) and new fuel hose (installed on the pump). Secure the hose connections with clamps. ,..Due to the low pressure output of this pump, it is recommended that the air gauge of the Dual Fuel/Air Pressure Gauge {91-852087A1/A2) be connected to the Schrader valve. The gauge should indicate 6-9 psi (41.37-62.04 kPa) High Pressure Pump Output t See Figures 109 and 110 1. On the 115, 135 and 150hp models. instafl the Dual Fuel/Air Pressure Gauge assembly to the PORT fuel rail pressure test valve. 4 -Shtader Yalvt (22·849606) 0519-IG()I Fig. 105 Exploded view of the fuel pres· sure regulator assembly Fig. 106 Remove the caps on the fuel rail Schrader valves Fig. 107 Low pressure fuel pump test on the 115, 135 and 150hp models .. . 1-0..e.tFuotl-lo:.O 2 •Lo.Pr.re aeet,..,FueiP.. 3-FuetWOSit(CibUinli::lallf)') 4 (22-849806) OS194G05 Fig. 108 . . . and the same test on the 200 and 225hp 05194600 Fig. 109 Testing the high pressure fuel pump on the 115, 150 and 150 hp models . . . Fig. 110 ... and the same set·up on the 206-225 hp models " . ! 4-76 FUEL SYSTEM I •Ft.letln(edef2:·FvldFtegublOf S·A.irA.. 5-Fwll..l•r.xc."FIJIIRei.WI\to\'Sf /•.CO"Qieek\'»twi e •Vhlr.tlnlatb(:cr.lngF..Rail t·Exoe$$A"r 10.. Mate lO •90pai(616lP.t)fU!f H ·110>lti(S41.0ltP41)Alr 0519461$ •• .. .....1o.. '·&ca:s.sfuo! R#tUII'I loVST' J-40J)tiCI'eckV&h1!• ·w.. ''*'Sot Ccdng Futl Rai9·..NIIOAIII-"'enum 10-90 psi (616.1(P.)FLM:II 11 -80 pSI (SC7.4ttP:.)A!t C5\94GI6 05195653 Fig. 111 Fuel rail assembly-115, 135 and 150 hp Fig. 112 Fuel rail assembly-200 and 225 hp Fig. 113 Location of the Shift Interrupt Switch and the electrical connector 2. On the 200-2!5hp models, install the test assembly to the STARBOARD fuel rail pressure test valve. 3. Mer 15seconds of engine cranking with the starter motor, the fuel pressure gauge should measure 87-91 psi (599.7-627.3 kPa). Fuel Rail REMOVAL & INSTALLATION • See Figures 111 and 112 1. De-pressurize fuel system. 2. Remove the fuel injector harness from each injector by compressing the spring clip with a Jlal tip screw driver while pulling on the connector. .. Always remove the fuel/air hose and filling together by removing filling retainer rather than cutting the clamps. 3. Remove the fuel, water and air hoses from the fuel rail. .. u is recommended that direct injectors remain in the cylinder head (if they are not to be replaced) while removing the fuel rail. The direct injectors have a Teflon seal which may expand if the injector is removed from the head. This expansion may cause reinstallation difficulties or require the replacement of the seal. 4. Remove !he two nuts securing the fuel rail. 5. As the fuel rail is removed, use a flat tip screwdriver to hold the direct injectors in the cylinder head. 6. The starboard fuel rail contains 3 fuel injectors and a tracker valve. The port fuel rail contains 3 fuel injectors, 1 fuel regulator and 1 air regulator. To install: 7. Carefully slide the fuel rail over the mounting studs and onto the direct injectors. ** WARNING The air hose must be secured with stainless steel hose clamps. 8. Secure each fuel rail with 2 nuts. Torque the nuts to 33 ft. lbs. (44 Nm). 9. Reinstall the direct injector harness connectors. CLEANING & INSPECTION Aller all fuel injectors, air regulator, tracker valve, fuel regulator, inlet hoses and outlet hoses have been removed, the fuel rai Is may be flushed out with a suitable parts cleaning solvent Use compressed air to remove any remaining solvent. Each fuel/air inlet or outlet hose adaptor has 2 0-ring seals. Theses 0-rings should be inspected for cuts, delormities or abrasions and replaced as necessary when the fuel rail is disassembled for inspection and cleaning. Manifold Absolute Pressure (Map) Sensor TESTING 1. Connecting a hand held vacuum pump and drawing a vacuum on the MAP sensor hose will create a lean fuel condition altering engine operation. If no change occurs when drawing the vacuum, the MAP sensor is not functioning properly. 2. Using a multimeter, check the voltage change in the MAP sensor. As you vary the vacuum, the voltage reading should raise or lower. Normal voltage is 0 to 5 volts, depending on air pressure . REMOVAL & INSTALLATION 1. Disconnect the MAP sensor wiring connector at the harness . 2. Remove the retaining boll and remove the MAP sensor. To install: 3. Connect the MAP sensor wiring harness at lhe connector. 4. Install the MAP sensor and tighten lhe retaining bolt. Shift Interrupt Switch TESTING 1. Using a multimeter, check the continuity ol lhe switch. 2. With the outboard in neutral, the swilch is closed (showing continuity) and normally open (no continuity) when in gear. 3. If the switch does not test within specification, it may be faulty and will need to be replaced. REMOVAL & INSTALLATION • See Figure 113 l Remove the bottom cowling. 2. Disconnect the shill interrupt switch bullet connectors. 3. Remove the retaining screws and remove the switch. To install: 4. Install the switch on lhe powerhead and secure with the retaining screws. 5. Connect the switch bullet connectors. 6. Install the bottom cowling. FUEL SYSTEM 4·11 Throttle Plate Assembly REMOVAL & INSTALLATION ,. The·throHie plate assembly is tallbrated and preset for proper running characteristics and emissions at the factory. Other than the complete assembly removal from the air plenum, no further disassembly should be made. 1. Remove Ute bolls securing the throttle plate to the air plenum and remove the throtlle plate. To Install: 2. Install the throtlle plate. 3. Install the bolls and lorque to 100 inch lbs. (11.5 Nm). Tracker Valve REMOVAL & INSTALLATION 1. Remove the screws securing !he tracker valve assembly and remove it from the lueVair rail. To Install: 2. Apply a light coat ol Quicksilver 2-4-C w/feflon lo the tracker diaphragm and cover 0-ringto aid in the1r relenlion on !he fuel rail while reinstallingthe tracker valve lo the fuel rail. ,.Apply anti-seize grease or Quicksilver 2-4-C to the tra.cker valve aHachlng screw threads. 3. Posl!ion the diaphragm, spring and 0-ring onlo the luel rail.4. Place the cover over the diaphragf!Vspring/O;ing assembly and secure it with 4screws. Torque the screws to70 inch lbs. (8.0 Nm). 1. Removethe screws securing theseparator coverand remove the cover. 2. The fuel pump may be removed lrom.lhe cover by slightly wiggling it while pulling outward. :;:::: CAUTION Do not twist the pump during removal. Doing so may damage the wiring harness. Vapor Separator REMOVAL & INSTALLATION 1. De-pressurl7ethe fuel system. 2. Place a suitable container underneath the vapor separator drain plug and drain the separator. 3. Disconnect the water separator sensor lead. 4. Disconnect !he electric luel pump harness connectors. 5. Remove the straps securingthe fuel hoses. ,.Upper hose is the excess fuel return from the fuel rails and the lower hose is the fuel Inlet from the electric pump beside the fuel/water separator. 6. Remove theluel lnlel hose from the pulse fuel pump. 7. Remove !he fuel outlet hose and the fuel return hosefromthe fuel rails. 8. Remove the bolts and !hen remove the vapor separator. To Install: 9. Seo.nethe vapor separator to the air plenum. Torque the bolts to 140inch lbs. (16.0 Nm). ..III(;.5 Fig. 114 Temperature sensor resistance UNDERSTANDING AND TROUBLESHOOTING ELECTRICAL SYSTEMS 5·2 BASIC ELECTRICAL THEORY 5-2 HOW ELECTRICITY WORKS: THE WATER ANALOGY 5-2 OHM'S LAW 5-2 ELECTRICAL COMPONENTS 5-2 POWER SOURCE 5·2 GROUND 5·3 PROTECTIVE DEVICES 5-3 SWITCHES & RELAYS 5-3 LOAD 5-4 WIRING & HARNESSES 5-4 CONNECTORS 5-4 TEST EQUIPMENT 5·4 JUMPER WIRES ..-4 TEST LIGHTS 5-S MULTIMETERS 5-5 TROUBLESHOOTING THE ELECTRICAL SYSTEM 5·6 VOLTAGE 5·6 VOLTAGE DROP 5·6 RESISTANCE 5-6 OPEN CIRCUITS 5-6 SHORT CIRCUITS 5-7 WIRE AND CONNECTOR REPAIR 5-7 BREAKER POINTS IGNITION (MAGNETO IGNITION) 5·8 DESCRIPTION & OPERATION 5·8 SYSTEM COMPONENTS 5-8 TROUBLESHOOTING THE BREAKER POINTS IGNITION SYSTEM 5-8 SPARK PLUGS 5-9 COMPRESSION TEST 5-9 BREAKER POINTS 5-9 POINT GAP CHECK 5-9 REMOVAL & INSTALLATION 5-11 CONDENSER 5-12 TESTING 5-12 REMOVAL & INSTALLATION 5-12 PRIMARY COIL 5-13 TESTING 5-13 :r REMOVAL & INSTALLATION 5-13 IGNITION COIL 5-13 TESTING 5-13 REMOVAL & INSTALLATION 5-14 CAPACITOR DISCHARGE IGNITION (COl) SYSTEM 5·14 DESCRIPTION AND OPERATION 5-14 2.5-3.3 HP 5-15 4-275 HP 5-15 TROUBLESHOOTING THE COl SYSTEM 5·15 TROUBLESHOOTING WITH MINIMAL TEST EQUIPMENT 5-15 TROUBLESHOOTING BATTERY CD IGNITIONS 5-16 TROUBLESHOOTING ALTERNATOR DRIVEN IGNITIONS 5-16 TRIGGER (CHARGE) COIL 5-16 TESTING 5-16 REMOVAL & INSTALLATION 5-18 IGNITION COIL 5-25 TESTING 5-25 REMOVAL & INSTALLATION 5-26 CAPACITOR DISCHARGE MODULE (SWITCH BOX) 5-27 TESTING 5-27 REMOVAL & INSTALLATION 5-28 CHARGING CIRCUIT 5·30 DESCRIPTION AND OPERATION 5-30 TROUBLESHOOTING THE CHARGING SYSTEM 5-30 STATOR (ALTERNATOR) 5-30 TESTING 5-30 REMOVAL & INSTALLATION 5-31 RECTIFIER 5-34 TESTING 5-34 REMOVAL & INSTALLATION 5-34 REGULATOR/RECTIFIER 5-34 TESTING 5-34 REMOVAL & INSTALLATION 5-38 BATTERY 5-38 BATTERY CONSTRUCTION 5-38 MARINE BATTERIES 5-38 BATTERY RATINGS 5-38 BATTERY LOCATION 5-39 BATTERY CHARGERS 5-39 BATTERY CABLES 5-40 STARTER CIRCUIT 5-40 DESCRIPTION AND OPERATION 5-40 TROUBLESHOOTING THE STARTING SYSTEM 5-40 STARTER MOTOR 5-41 REMOVAL & INSTALLATION 5-41 STARTER SOLENOID 5-41 TESTING 5-41 IGNITION AND ELECTRICAL WIRING DIAGRAMS 5·42 SPECIFICATIONS CHARTS IGNITION TESTING SPECIFICATIONS 5-17 STATOR ALTERNATOR RESISTANCE SPECIFICATIONS 5-30 SMALL VOLTAGE REGULATOR TEST (STATIC) 5-35 TROUBLESHOOTING CHARTS RECTIFIER TROUBLESHOOTING -TEST "A" 5-37 RECTIFIER TROUBLESHOOTING -TEST "B" 5-37 'f r ' · · 5-2 IGNITION AND ELECTRICAL SYSTEMS UNDERSTANDING AND TROUBLESHOOTING ELECTRICAL SYSTEMS Basic Electrical Theory • .See Figure 1 Forany 12 v.olt, negalive ground, electrical system to operate, the electricity must travel in a complete circuit. This simply means thal current (power) from the positive terminal (+) of the battery must eventually return to the negative terminal (-) of the battery. Along theway, this current will travel through wires. fuses. switches and components. If lor any reason the flow of current through the circuit is interrupted, thecomponent(s) led by that circuit will cease to function properly. Perhaps the easiest way to visualize a circuit is to think of connecting a light bulb (wit.. twowires attached to it) to the battery-onewireattachedto the negative (-) termmal of the battery and the other wire to the positive (+) terminal. With the two wires touching the battery terminals. the circuit would be complete and the light bulb would illuminate. Electricity would follow a path from the battery to the bulb and back to the battery. Irs easy to see that with longer wires on our light bulb, it could be mounted anywhere. Further, one wire could be lilted with a switch so that the light could beturned on and off. The normal marine circuit differs from this simple example in two ways. First, instead of having a rCi"urn wire from each bulb to the battery, the current travels through a single ground wire. which handles all the grounds for a specific circuit. Secondly, mosl marine circuits contain multiple components, which receive power from a single circuit. This lessens the amount of wire needed to power components. POWER SOURCE (BATIERY) RETURN CONDUCTOR GROUND PROTECTION DEVICE (FUSE) LOAD (BULB) CONTROL DEVICE (SWITCH OPEN) RETURN CONDUCTOR GROUND TCCS2004 Fig. 1 This example illustrates a simple circuit. When the switch is closed, power from the positive (+) battery terminal flows through the fuse and the switch and then to the light bulb. The light illuminates and the circuit is completed through the ground wire back to the negative (-} hattery terminal. HOW ELECTRICITY WORKS: THE WATER ANALOGY Electricity is the flow of electrons-the sub-atomic particles that constitute the outer shell of an atom. Electrons spin in an orbit around the center core of an atom. The center core is comprised of protons (positive charge) and neutrons (neutral charge). Electrons have a negative charge and balance out the positive charge of the protons. When an outside force causes the number of electrons to unbalance the charge of the protons, the electrons will split ott the atom and look for another atom to balance out. If this imbalance is kept up, electrons will continue to move and an electrical flow will exist. Many people havebeen taught electrical theory using an analogy with water. In a comparison with water flowing through a pipe, the electrons would be the water and the wire is the pipe. The flow of electricity can be measured much like the !low of water through a pipe. The unit of measurement used is amps, frequently abbreviated as amps (a). You can compare amperage to the volume of water flowing through a pipe. When connected to a circuit, an ammeter will measure the actual amount of current !lowing through the circuit. When relativelyfewelectrons flowthrough a circuli. the amperage is tow. When manyelectrons flow, the amperage is high. Water pressure is measured in units such as pounds per square inch (psi). electrical pressure is measured in units called volts (v). When a voltmeter is connected to a circuit. itis measuring the electrical pressure. When electrical pressure is tow, then voltage is considered to be low. When electrical pressure is high, then voltage is considered to be high. The actual!low of electricity depends not only on voltage and amperage but also on the resistance of the circuit. The higher the resistance. the higher the force necessary to push the current through the circuit. The standard unitlor measuring resistance is an ohm (0}. Resistance in a circuit varies depending on the amount and type of components used in the circuitand the overall condition ol the components and wires. If we assume that everything in our circuit is new, then, the main factors which determine resistance are: • Material-some materials have more resistance than others. Those with high resistance are said to be insulators. Rubber materials (or rubber-like plastics) are some of the most common insulators used. as they have a very high resistance to electricity. Very low resistance materials are said to be conductors. Copper wire is among the best conductors. Silver is actualfy a superior conductor to copper and is used insome relay contacts but its high cost prohibits its use as common wiring. Most marine wiring is made of copper. • Size-the larger the wire size being used. the Jess resistance the wire will have. This is why components which use farge amounts ol electricity usually have large wires supplying current to them. • Length-lor a given thickness of wire, the longer the wire. the greater the resistance. The shorter the wire, the less the resistance. When determining the proper wire for acircuit,both size and length must be considered to design a circuitthat can handle the current needs of the component. • Temperature-with many materials, the higher the temperature, the greater the resistance (positive temperature coeflicienl). Some materials exhibit the opposite trail of lower resistance with higher temperatures (negative temperature coellicient). These principles are used in many of the sensors on the engine. OHM'S LAW There is a direct relationship between current. voltage and resistance which can be summed up by a statement known as Ohm's law. • Voltage (E) is equal to amperage (I) limes resistance (R): E=l x R • Other forms oftheformula are R=E/1 and I=EIR In each of these formulas. E is the vollage in volts. 1 is the current in amps and R is the resistance in ohms. The basic point to remember is that as the resistance of a circuit goes up, the amount of current that flows in the circuit will go down, if voltage remains the same. The amount of work that the electricity can perform is expressed as power. A unit of power is known as a watt (W). There is a direct relationship between power. voltage and current which can be summed up by the following formula: • Power (W) is equal to amperage (I) times voltage (E): W=l x E ,.. This formula is only true tor direct current (DC} circuits, The alternating current formula is a tad different but since the electrical circuits in most boats are DC type, we need not get into AC circuit theory. Electrical Components POWER SOURCE • See Figure 2 Power is supplied to the boat by two dev ices: The batlery and the alternator (stator). The battery supplies electrical power during starting or during periods when the current demand of the boat's electrical system exceeds the output capacity of the alternator. The alternator supplies electrical current when the engine is running. The alternator does not just supply the current needs of the boat but it also recharges the batlery. In most modern boats, the battery is a lead/acid electrochemical device consisting ofsix2 voltsubsections (cells) connected in series. so that the unit is capable of producing approximately 12 volts of electrical pressure. Each subsection consists of a series of positive and negative plates held a short distance apart in a solution of sulfuric acid and water. The twotypes of plates are of dissimilar metals, which sets up a chemical reaclion insidethe battery case. I! is this reaction which produces current flow from the battery when its positive and negative terminals are connected to an electrical toad. The alternator.restoring the battery to its original chemical state replaces the power removedfrom the battery. IGNITION AND ELECTRICAL SYSTEMS 5-3 00577001 Fig. 2 Functional diagram ol a typical charging circuit showing the relationship ol the stator, solid state rectifier and the battery The following is a brief description of how the system works: The battery stores electricity and acts as a "sponge• for the whole system. It mops up generated current until it's fully charged and it release s energy on demand. The flywheel holds the permanent magnets thai create the moving magnetic fieldIf your engine has good spark. you can take it for granted that the magnets are in working order because the ignition and charging systems share the same magnets. Thestator windings are the stationary coils of wire the flywheel magnets rotate around. They produce the electrical charge. Simply put the more windings in your stator, the greater the potential output in amps your charging system you'll have. The rectifier consists of a series of diodes or electrical one-way valves. The rectifier overcomes one of the disadvantages of a current-generating system using permanent magnets and stator windings, which is that the current produced within the windings is alternating current (AC). You can't use AC lo charge balleries. They accept only direcl current (DC). So the rectifier is designed lo convert AC current to a usable form of DC current simply called "rectified AC." On larger outboards. there may be a voltage regulator. either combined with the rectifier or standing atone. The regulator automatically reduces the output of generated current as the battery becomes fully charged. GROUND All boats use some sort ol a ground return circuit. Direct ground components are grounded to an electrically conductive metal component through their mounting points. These electrically conductive metal components are then grounded to the battery All other components use some sort of ground wire which leads directly back to the battery. The electrical current runs through the ground wire and returns to the battery through the ground (-) cable. If you look, you'll see that the battery ground cable connects between the battery and a heavy gauge ground wire. ,..It should be noted that a good percentage ol electrical problems can be traced to bad grounds. PROTECTIVE DEVICES • See Figure 3 It is possible for large surges ofcurrent to pass through the electrical system of your boat. Ifthissurge of current were to reach components in thecircuit, the surge could burn them out or severely damage them. Surges can also overload the wiring, causing the harness lo get hot and melt the insulation. To prevent this, fuses, circuit breakers and/or fusible links are connected into the supply wires of the electrical system. These items are nothing more than a buill-in weak spot in the system. When an abnormal amount of current flows through the system, these protective devices work as follows to protect the circuit: • Fuse-when an excessive electrical current passes through a fuse, the ruse •btows" (the conductor melts) and opens the circuit, preventing the passage of current. • Circuit Breaker-a circuit breaker is basically a self-repairing fuse. It will open the circuit in the same fashion as a fuse but when the surge subsides. the circuit breaker can be reset and does not need replacement. • Fusible Link--a fusible link (fuse link or main link) is a short length of spe- Fig. 3 Fuses protect the vessel's electrical system from abnormally high amounts ol current flow cial, high temperature insulated wire that acts as a fuse. When an excessive electrical current passes through a fusible link, the thin gauge wire inside the link melts, creating an intentional open to protect the circuit. To repair the circuit, the link must be replaced. Some ne-wer type fusible links are housed in plug-in modules, which are simply replaced like a fuse, while older type fusible Jinks must be cut and spliced if they melt. Since this link is very early in the electrical path, it's the first place to look il nothing on the boat works, yet the baHery seems to be charged and is properly connected. ** CAUTION Always replace ruses, circuit breakers and fusible links with identically rated components. Under no circumstances should a component of higher or lower amperage rating be substituted. SWITCHES & RELAYS • See Figure 4 SWitches are used in electrical circuits to control the passage of current. The most common use is to open and close circuits between the batlery and the various electric devices in the system. Switches are rated according to the amount of amperage they can handle. If a sufficient amperage rated switch is not used in a circuit, the switch could overload and cause damage. SWITCH B+ r--.D:----1------, I as I I .. I I I RELAYRELAYCOIL : 86 :L--J.---J------J GROUND CONPONENT Fig. 4 Relays are composed of a coil and a switch. These two components are linked together so that when one operates, the other operates at the same time. The large wires in the circuit are connected !rom the battery to one side of the relay switch (B+) and from the opposite side of the relay switch to the load (component). Smaller wires are connected from the relay coil to the control switch for the circuit and !rom the opposite side of the relay coil to ground 5-4 IGNITION AND ELECTRICAL SYSTEMS Some electrical components which require a large amount of current to operate use a special switch called a relay. Since these circuits carry a large amount of current, the thickness of the wire in the circuit is also greater. II this large wire were connected from the load to the control switch, the switch would have to carry the high amperage load and the space needed lor wiring in the boat would be twice as big to ac..ommodate the increased size ol the wiring harness. To prevent these problems. a relay is used. Relays are composed of a coil and a set of contacts. When the coil has a current passed though it, a magnetic field is formed and this fieid causes the contacts to move together, completing the circuit. Most relays are normally open, preventing current from passing through the circuit but they can lake any electrical form depending on the job they are intended to do. Relays can be considered ·remote control switches.· They allow a smaller current to operate devices that require higher amperages. When a small current operates the coil, a larger current is allowed to pass by the contacts. Some common circuits which may use relays are horns, lights, starter, electric fuel pumps and other high draw circuits. LOAD Every electrical circuit must include a "load' (something to use the electricity coming from the source). Without this load, the battery would attempt to deliver its entire power supply from o..·pole to another. This would resull in a "short circuit' of the battery. All this electricity would take a short cut to ground and cause a great amount of damage to other components in the circuit by developing a tremendous amount of heat. This condition could develop sufficient heat to meit the insulation on all the surrounding wires and reduce a multiple wire cable to a lump of plastic and copper. WIRING & HARNESSES The average boat contains miles or wiring, with hundreds or individual connections. To protect the many wires from damage and to keep them from becoming a confusing tangle, they are organized into bundles. enclosed in plastic or taped together and called wiring harnesses. Different harnesses serve different parts of the boat Individual wires are color coded to help trace them through a harness where sections are hidden from view. Marine wiring can be either single strand wire, multi-strand wire or printed circuitry. Single strand wire has a solid metal core and is usually used illside such components as alternators. motors, relays and other devices. Multi-strand wire has a core made or many small strands of wire twisted together into a single conductor. Most of the wiring in a marine electrical syslem is made up ol multi-strand wire, either as a single conductor or grouped together in a harness. All wiring is color coded on the insulator, either as a solid color or as a colored wire with an identification stripe. A prinled circuit is a thin film of copper or other conductor that is printed on an Insulator backing. Occasionally, a printed circuit is sandwiched between two sheets of plastic for more protection and flexibility. A complete printed circuit, consisting of conductors, insulaling material and connectors Is called a printed circuit board. Printed circuitry is used in place of individual wires or harnesses in places where space is limited, such as behind instrument panels. Since marine electrical systems are very sensitive to changes in resistance, the selection of properly sized wires is critical when systems are repaired. A loose or corroded connection or a replacement wire that is too small for the circuit will add extra resislancc and an additional voltage drop to the circuit. The wire gauge number is an expression of the cross-section area of the conductor. Boats from countries.that use the melric system will typically describe the wire size as its cross-sectional area in square millimeters. In this method, the larger the wire, the greater the number. Another common system for expressing wire size is the American Wire Gauge (AWG) system. As gauge number increases, area decreases and the wire becomes smaller. An 18 gauge wire is smaller than a 4gauge wire. A wire with a higher gauge number will carry less current than a wire with a lower gauge number. Gaugewire size refers to the size of the strands of the conductor, not the size or the completewire with insulator. It is possible, therefore, to have two wires of the same gauge with different diameters because one may have thicker insulation than the other. It is essential to understand how a circuit works before trying to figure out why it doesn't. An electrical schematic shows the eleclrical current paths when a circuit is operating properly. Schematics break the entire electrical system down into individual circuits. In a schematic, usually no attempt is made to represent wiring and componenls as they physically appear on the boat, switches and other components are shown as simply as possible. Face views of harness connectors show the cavity or terminal locations in all multi-pin connectors to help locate test points. CONNECTORS t See Figures 5, 6, 7 and 8 Weatherproof connectors are most commonly used where the connector is exposed to the elements. Terminals are protected against moisture and dirt by sealing rings which provide a wealher light seal. All repairs require the use of a special terminal and the tool required to service it. Unlike standard blade type terminals, these weatherproof terminals cannot be straightened once they are bent. Make certain that the connectors are properly seated and all of the sealing rings are in place when connecting leads. Test Equipment Pinpointing the exact cause of trouble in an electrical circuit is most times accomplished by the use of special test equipment. The following sections describe different types of commonly used test equipment and briefly explain how to use them In diagnosis. tn addition to the information covered below, the tool manufacturer's instruction manual (provided with most tools) should be read and clearly understood before attempting any test procedures. JUMPER WIRES • See Figure 9 ** CAUTION Never use jumper wires made from a thinner gauge wire than the circuit being tested. If the jumper wire is of too small a gauge, it may overheat and possibly melt. Never use jumpers to bypass high resistance loads in a circuit. Bypassing resistances, in effect, creates a short circuit. This may, in turn, cause damage and fire. Jumper wires should only be used to bypass lengths of wire or to simulate switches. Jumper wires are simple, yet extremely valuable, pieces of lest equipment. They are basically test wires which are used to bypass sections or a circuit. Although jumper wires can be purchased, they are usually fabricated from lengths of standard marine wire and whatever lype of connector (alligator clip, spade connector or pin connector) thai is required for the particular application being tested. In cramped, 05195PIS Fig. 5 Bullet connectors are some of the more common electrical connectors found on an outboard engine Fig. 6 A typical weatherproof electrical connector TCCMP03 Fig. 7 Hard shell (left) and weatherproof (right) connectors have replaceable terminals IGNITION AND ELECTRICAL SYSTEMS 5-5 Of.I75P$2 Fig. 8 The seals on weatherprool connectors must be kept in good condllion to prevent the terminals from corroding Fig. 9 Jumper wires are simple, yet extremely valuable, pieces of test equipment Fig. 10 A test light is used to detect the presence of voltage in a circuit hard-to-reach areas, it is advisable to have insulated boots over the jumper wire terminals in order to prevent accidental grounding. It isalso advisable to IIJ..Iude a standard marine luse in any jumper wire. This is commonly referred toas cr"lused jumper". By inserting an in-line fuse holder between a set of test leads, a fused jumper wire can be used for bypassing open circuits. Use a 5 amp fuse to provide protection against voltage spikes. Jumper wires are used primarily to locate open electrical circuits. If an electrical component fails to operate, connect the jumper wire between the component and a good ground. li the component operates only with the jumper installed. the ground circuit is open. If the ground circuit is good but the component does not operate, the circuit between the power feed and component may be open. By moving the jumper wire successively back from the component toward the power source. you can isolate the area ol lhe circuit where the open is located. When the component stops functioning or the power is cut off, the open is in the segment of wire between the jumper and the point previously tested. You can sometimes connect the jumper wiredirectly from the battery to the "hot" terminal or the component bul first make sure the component uses 12 volts in operalion. Some electrical components, such as fuel injectors or sensors are designed to operate on about 4 to 5 volts and running 12 vails directly to these components will cause damage. TEST UGHTS t See Figure 10 The test light is used to check circuits and components while electrical current is flowing through them. II is used for voltage and ground tests. To use a 12 volt !esl light, connectthe ground clip to a good ground and probewherever necessary with the pick. The test light will illuminate when voltage is detected. This does not necessarily mean that 12 volts (or any particular amount of voltage) is present, ij only means that some voltage is present. ,..II is advisable before using the test light to touch its ground clip and probe across the battery posts or terminals to make sure the light is operating properly. ** WARNING Do not use a test light to probe electronic ignition, spark plug or coil wires. Never use a pick-type test light to probe wiring on electronically controlled systems unless specifically instructed to do so. Any wire insulation that is pierced by the test light probe should be taped and sealed with silicone after testing. Like lhe jumper wire, the 12 volt test light is used to isolate opens in circuits. But, whereas the jumper wire is used to bypass 1he open to operate the load, the 12 vall test light is used to locate the presence of voltage in a circuit. II the test light illuminates, there is power up to thai point in the circuit, if the test light does not illuminate, there is an open circuit (no power). Move the test light in successive steps back toward the power source until the light in the handle illuminates. The open is between the probe and a point which was previously probed. The self-powered test light is similar in design to lhe 12 volt test light but contains a 1.5 volt penlight battery in the handle. It is most often used in place of a multimeter to check for open or short circuits when power is isolated from the circuit (continuity test). The battery in a sell-powered lest light does not provide much current. A weak battery may not provide enough power to illuminate the test light even when a complete circuit is made (especially if there is high resistance in the circuit). Always make sure that the test battery is strong. To check the battery. brielly touch the ground clip to the probe, if the light glows brightly,the battery is strong enough for testing. ** WARNING A self-powered test light should not be used on any electronically controlled system or component. The small amount of electricity transmitted by the test light is enough to damage many electronic marine components. MULTIMETERS t See Figure 11 Multime!ers are an extremely useful tool lor troubleshooting electrical problems. They can be purchased in either analog or digital form and have a price range to suit any budget. A multimeter is a voltmeter, ammeterand multimeter (along with other features) combined into one instrument. II is often used when testing solid stale circuits because of its high input impedance (usually 10 megaohms or more). A brief description ol the multimeter main test functions follows: •Vollmeter-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 damage to the meter, always connect the negative lead to the negative () side of Ihe circuit (to ground or nearest the ground side of the circuit) and connect the positive lead to the positive (+) side ol the circuit (to the power source or the nearest power source}. Fig. 11 Multimeters are essential for diagnosing faulty wires, switches and other electrical components :r 5-6 IGNITION AND ELECTRICAL SYSTEMS ,..The negative voltmeter lead will always be Black and that the positive voltmeter will always be some color other than Black (usually Red). • Mullimeter-the mullimeter is designed to read resistance (measured in ohms) in a circuit or component. Most mullimeters wi II have a selector switch wh!ch permits the measurement of different ranges of resistance (usually the selector sw1tch allows the mulliplication of the meter reading by 10, 100, 1,000 and 10,000). Some multimeters are "auto-ranging• which means the meter itself will determine which scale to use. • Since an internal baHery powers the meters. the multimeter can be used like a self-powered test light. When the mullimeler is connected, current from the multimeter flows through the circuit or component being tested. Since the multimeter's internal resistance and voltage are known values. the amount ol current flow through the meter depends on the resistance of the circuit or component being tested. The multimeter can also be used to perform a continuity test for suspected open circuits. In using the meter for making continuity checks, do not be concerned with the actual resistance readings. Zero resistance (or any ohm readmg) indicates continuity in the circuit. Infinite resistance indicates an opening in the circuit. A high resistance reading where there should be none indicates a problem in the circuit. Checks tor 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 n!J.continuity, while zero resistance indicates a dead short. :::::: WARNING Never use a multimeter 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 amps (amps). AI normal operating voltage, most circuits have a characteris!ic amount of amps, called "current draw· which can be measured using an ammeter. By referring to a specified current draw rating, then measuring the amps and comparing the two values, one can determine what is happening within the circuit to aid in diagnosis. For example, an open circuit 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 !lows through the circuit must also flow through the ammeter, il there is any other path for the current to follow, the ammeter reading wi II not be .accurate. The ammeter itself has very little resistance to current flow and, therefore, 1t 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 !uses 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. Troubleshooting the Electrical System When diagnosing any electrical problem organized troubleshooting is a must. The complexity of electrical systems on modern boats and their power plants dem..nds that you approach any problem in a logical organized manner. There are certa1n troubleshooting techniques, which are standard: • Establish when the problem occurs-Does the problem appear only under certain conditions? Were there any noises. odors or other unusual symptoms? • Check for obvious problems-Problems such as broken wires and loose or dirty connections can cause major problems. Always check the obvious before assuming something complicated (or expensive) is the cause. ,..Experience has shown that most problems tend to be the result of a fairly simple and obvious cause, such as loose or corroded connectors, bad grounds or damaged wire insulation, which causes a short. This makes careful visual inspection of components during testing essential to quick and accurate troubleshooting. • Isolate the problem area-Make some simple tests and observations, then eliminate the systems that are working properly. Test for problems systematically to determine the cause once the problem area is isolated. Are all the components functioning properly? Is there power going to electrical switches and motors. Performing careful, systematic checks will often turn up most causes on the first inspection, without wasting time checking components that have little or no relationship to the problem. • Verify all systems after repairs are completed-Some causes can be traced to more than one component, so a careful verification of repair work is important in order to pick up additional malfunctions that may cause a problem to reappear or a different problem to arise. A blown iuse, for example, is a simple problem that may require more than another fuse to repair. If you don't look for a problem that caused a fuse to blow, a shorted wire (for example) may go undetected. VOLTAGE • See Figure 12 This test determines voltage available from the battery and should be the first step in any electrical troubleshooting procedure after visual inspection. Many electrical problems, especially on electronically controlled systems, can be caused ..Y a low state of charge in the battery. Excess1ve c-arros10n at the battery cable term1nals can cause poor contact that will prevent proper charging and lull battery current flow. 1. Set the voltmeter selector switch to the 1a-volt position. 2. Connect the multi meter negative lead to the ballery's negative (-) terminal and the positive lead to the battery's positive ( +) terminal. 3. Turn the battery (ignition) switch ON to provide a toad. 4. A well charged battery should registef over 12 volts. If the meter reads below 11.5 volts, the battery power may be insuHicient lo opelate the electrical system properly. 5. Charge the ba!lery and retest. VOLTAGE DROP • See Figure 13 When current flows through a load, the voltage beyond the toad drops. This voltage drop is due to the resistance created by the load ..nd al..o by small resistances created by corrosion at the connectors and damaged msulat10n on the w1res. The maximum allowable voltage drop under load is critical. especially if there is more than one load in the circuit, since all voltage drops are cumulative. 1. Set !he voltmeter selector switch to the 10-volt position. 2. Connect the mullimeter negative lead to the battery negative (-) terminal or another good ground. 3. Touch the multi meter positive lead to the battery's positive ( +) terminal to determine battery voltage. 4. Operate the circuii and check the voltage prior to the first comp..nent (l. oad). 5. There should be little or no voltage drop (from battery voltage) 10 the c1rcu1t prior to the first component. If a voltage drop exists. the wire or connectors in the circuit are suspect. 6. While operating the first component in lhe circuit. probe the ground ..ide of the component with the positive ( +) meter lead and observe the voltage readmgs .. A small voltage drop should be noticed. The resistance ot the component causes th1s voltage drop. 7. Repeat the test for each component (load) down the circuit. B. If a large voltage drop is noticed, the preceding component, wire or connector is suspect. RESISTANCE • See Figures 14 and 15 ** WARNING Never use a multimeter with power applied to the circuit. The multimeter is designed to operate on its own power supply. The normal 12-volt electrical system voltage can damage the meter! 1. Isolate the circuit from the boars power source. 2. Ensure that the battery (ignition) switch is OFF. 3. Isolate at least one side of the circuit to be checked, in order to avoid reading parallel resistances. Parallel circuit resistances will always give a lower reading than the actual resistance of either of the branches. 4. Connect the meter leads to both sides ol the circuit (wire or component) and read the actual resistance measured in ohms on the meter scale. Make sure the selector switch is set to the proper ohm scale lor the circuit being tested, to avoid misreading the multimeter test value. 5. Compare this reading to the resistance specification lor the component or formulate the theoretical resistance using Ohms law. OPEN CIRCUITS • See Figures 16 and 17 This test already assumes the existence ol an open in the circuit and il is used to help locate the open portion. IGNITION AND ELECTRICAL SYSTEMS 5-7 OS195G68 OS195G57 Fig. 13 Voltage drop is due to the resis- Fig. 12 The voltage test determines voltage available from the battery and should be the first step in any electrical troubleshooting procedure after visual inspection tance created by the load and also by small resistances created by corrosion at the connectors and damaged insulation on the wires Fig. 14 Using a multi meter to check resistance on the secondary side of the ignition coil POSlTlYE OHMS-([)-NEGAliVE LEAD OJOOE / ... 05195G70 051..9 Fig. 15 When performing resistance tests, always isolate the circuit from power 0500:R;4 Fig. 16 The infinite display on this multimeter (1.) indicates that the circuit is Fig. 17 The easiest way to illustrate an open circuit is to consider an example circuit with a switch. When the switch is turned OFF, power does not flow through the circuit to the load. Thus, the circuit is open open 1. Isolate the circuit from power and ground. 2. Connect the self-powered test light or multimeter ground clip to the ground side of the circuit and probe sections of the circuit sequentiatry. 3. If the light is out or there is infinite resistance, the open is between the probe and the circuit ground. 4. If the light is on or the meter shows continuity, the open is between the probe and the end of the circuit toward the power source. SHORT CIRCUITS • See Figure 18 ,-Never use a sell-powered test light to perform checks lor opens or shorts when power is applied to the circuit under test. The test light can be damaged by outside power. 1. Isolate the circuit from power and ground.2. Connect the sell-powered test light or mullimeter ground clip to a good ground and probe any easy-to-reach point in the circuit. 3. li the light comes on or there is continuity,there is a short somewhere in the circuit. 4. To isolate the short. probe atest point at either end of the isolated circuit (the light should be on or the meter should indicate continuity). 5. Leave the test light probe engaged and sequentially open connectors or switches, remove parts, etc. unlil the light goes out or continuity is broken. 6. When the I ight goes out, the short is between the last two circuit components, which were opened. Wire and Connector Repair Almost anyone can replace damaged wires, as long as the proper tools and parts are available. Wire and terminals are available to fit almost any need. Even the specialized weatherproof, molded and hard shell connectors are now available from aftermarket suppliers. Be sure the ends ot all the wires are fitted with the proper terminal hardware and connectors. Wrapping a wire around a stud is never a permanent solution and will only cause trouble tater. Replace wires one at a lime to avoid confusion. Always route wires in the same manner of the manufacturer. When replacing connections, make absolutely certain that the connectors are certilied for marine use. Automotive wire connectors may not meet United States Coast Guard (USCG) specifications. ,-u connector repair is necessary, only attempt it if you have the proper tools. Weatherproof connectors require special tools to release the pins inside the connector. Attempting to repair these connectors with conventional hand tools will damage them. J1Ul.nHETER OS195G71 Fig. 18 1n this illustration, the circuit between the battery and light should be open because the switch is turned OFF. However, battery voltage is reaching the light at the point of the short. This could possibly be caused by chaffed wires 5-8 IGNITION AND ELECTRICAL SYSTEMS BREAKER POINTS IGNITION (MAGNETO IGNITION) Description & Operation • See Figure 19 The breaker point ignition consists ofthe rotorassembly, contact pointassembly, ignition coli, condenser spark plug, spark plug cap and theengine stop switch. The breaker points Ignition system uses a mechanically switched, collapsing field to inducespark at the plug. A magnet moving by a coil produces current in the primary coil winding. The current in the primary winding creates a magnetic field. N. the proper lime, the breakerpoints areseparated by action of a C2lll designed into the collar of the crankshall and the primary circuit is broken. When the circuit Is broken, lhellow ol primary current stops and causes the magnetic field about the coil to break down inslan!Jy.N. this precisemoment, an electrical current of extremely high voltage is induced in the fine secondary windings of the coil. This high vollage is conductedto the spark plug whereit JUmps the gap betweenthe pointsof the plug to Ignite the compressed charge ofair-fuel mixture in the cylinder. Breaker poinl ignilion systems Installed onoutboard engines wilt usually operate over extremelylong periods ol timewithout requiringadjustment or repair. However, If Ignition system problems are encounteredand the usual corrective actions such as replacement ofspark !)lugs docs not correct the problem, themagneto output should bechecked to determine il the unitIs functioningproperly. SYSTEM COMPONENTS Breaker Point Set • See Figure 2D A breaker pointset consrsts of two points. OneIs attached to a stationary bracket anddocs notmove. The other point is attached to a movablemount. A spring is used tokeep the points in contact wilh eachother, except when they are separated by the action of a cambuilt into the flywheelcollar which Iits over the cranks halt. Both points are constructed with a steelbase and a tungstencap I used to the base. Thebreaker points must be aligned accurately to provide the best contact surface. This is the only way lo assure ma)(jmum contact area between the point surfaces, accurate settingof lhe point gap, proper synchronization andsatisfactory pofnt life.If the points are not aligned property, the result will be premature wear or prtting. This type of damage may change the cam angle, although lheactual distance will remain !he same. Condenser • See Figure 21 Thebleaker point ignition system containsa condenser that works like a sponge Inthe circuit. Current that Is llowing through the primary circuit trieslo keep going. When lhe breaker point switch opens the current will arcover the widening gap. The condenser Iswired In parallel with thepoints.Thecondenser absorbs someof the current flow as thepoints open This reduces arc over and extends the me of the points. In simple terms, a condenser is composed of two sheets oltinoraturnlnumloll laid one ontop of the other but separated by a sheet ol insulating material such as waxed paper, etc_ The sheets arerolled rntoa cylinder toconseM space and then insertedlmo a metal case for protecllon and to permit easy assembling. CI5195Gill The purposeof the condenserIs lo prevent excessive arcing across lhepoints and to extend their useful life. When lhe !low ofprimary current is broughtto a sudden stop by theopening of the points,the magneticfield Jn the primary windings collapses instanlly and Isnot allowed to•tade away'', which would happen lithe points were allowed to arc. The condenser stores the electricity thai would have arced across thepoints and discharges thatelectricity when the points and close again. This discharge is in the opposite direction to the original flowand lends to ·smooth out• the current The more quickly the primaryfield collapses. thehigher the voltage produced In the secondary windings and delivered to the spark plugs. In this way, the conOOflser(in the primary circuil). affects thevoltage (in the secondary circuit) a! the spar.. plugs. Modern condensers seldom causeproblems, therefore, il is not necessary to installa new one each time Ihe poinls are replooed. Hov.-ever, if the points show evi· dence ol arcing, the condenser may be atfault and should be replaced. A faulty condenser may not bedetected wllhoul the use of special test equipment. 1esling will reveal any defects in the condenser but will not predict the useful life left In the unit. Themodest costot a new condenser justilies i!s purchase and inslallalion to etlminate thisitem asasourceof trouble. Primary Coil As the flywheelrotates. magnets attached to the edge of the flywheel create a currenl that will flow through the closed brea..erpoints into the ignition coil primary windings. This llow of current through the coil primary windings buildsa very strongmagnetic fie!d. When the brea..cr cam opens the points. the fieldcollapses, inducing high vollage in the coil secondarywinding. This voltage is scnl lo the spwk plug. The condenser will absorb any residual current remaining in lhepriMary windings while the points are open This eliminales arcing at the breaker points and In turn produces a strongerspark at lhe spark plug. Thellreaker points then close and the flywheel continues to rotate. Ignition Coil The ignition coilis theheart ollhe Ignition system. Essentially, il is nothing more than a transformerwhich takes a relatively low voltage(12 volts) available from the primary coil and increasesIt to the point where it williire the spark plugwith as much as 20.000 volls. Oncethevoltage is discharged fromthe ignition coil the secondary circuit begins and only stretchesfrom theignition coil to the spark plugs via extremely high-tension leads. N. the spark plug end, the vollage arcs in !he form ol a spark, across from the centC! electrode to the outer electrode and then to ground via spark plug threads. This completes the ignition circu1L Troubleshooting the Breaker Points Ignition System Always attempt to proceed with system testing In an orderly manner. The 'shot In thedark" approach will only resultIn wasted time, Incorrect diagnosis.replacement of unnecessary partsand lrustration. Beginthe ignition system troubleshooting wiih thespark plug andcontinue through the system unlit thesource of trouble Is located. Toproperty diagnose magneto (spark) problems, the theory of electricity flow must be understood. The flow of electricity through a wire may be comparedwith the flow of water through apipe. Consider tre voltage in the wire as lhe wal& pressure ALTERNATE LAYERS OF INSULATION ·WAXED PAPER fig. 19 Magneto ignition system components-- 2.2, 2.5 and 3hp Fig. 20 line drawing of a typical point set with principle parts Identified Ag. 21 This sketch illustrates how waxed paper, aluminum foil and insulation are rolled In the manufacture of a typical condenser IGNITION AND ELECTRICAL SYSTEMS 5-9 in the pipe and the amps as the volume of water. Now, if the water pipe is broken. the water does not reach the end of the pipe. In a similar manner if the wire is broken the flow of electricity is broken. If the pipe springs a leak, the amount of water reaching the end of the pipe is reduced. Same with the wire. If the installation is defective or the wire becomes grounded, the amount of electricity (amps) reaching the end ot the wire is.reduced. The breaker points in an outboard motor are an extremely imporlant pari of the ignition system. A set o! points may appear to be in good condition but they may be the source of hard starting, misfiring or poor engine performance. The rules and knowledge gained from association with 4-Stroke engines does not necessarily apply to a 2-Stroke engine. The points should be replaced every 100 hoursof operation or at least once a year. Remember, the less an outboard engine is operated, the more care it needs. Allowing an outboard engine to remain idle will do more harm than if it is used regularly. SPARK PLUGS t See accompanying illustrations 1. Remove the cowling. On 1990 2.5 and 3hp models, remove the fuel filler cap from the fuel tank. Press in on both sides of the upper cowling half and lin the upper cowling free. •· On the 2.5hp and 3hp..1991 and on-feleast the two snap latches on both sides of the cowling and lift the upper half of the cowling free of the powerhead. 2. Check the plug high-tension lead lo besure it is properly connected. Check the entire length of lhe lead from the plug to the secondary ignition coil. If the lead is to be removed from the spark plug, always use a twisting and pulling motion as a precaution against damaging the connection. 3. Attempt to remove the spark plug by hand. This is a "rough" test to determine if the plug is tightened properly. The attempt to loosen the plug by hand should fail. The plug should be tight and require the proper size socket for removal. Remove the spark plug and evaluate its condition. 4. Use a spark tester and check lor spark. Rotate the flywheel with the hand rewind starter and observe the I ight lor the spark. II a spark tester is not available, disconnect the lead from the spark plug, insert a screwdriver into the boot to make contact with the lead "shell" inside. hold the shank of the screwdriver close to the powerhead-say aboul'/4 in. (6.4mm) from the powerhead, have an assistant crank the powerhead, and observe the spark jumping the gap. A strong spark over a wide gap must be observed when testing in this manner. because under compression, a strong spark is required to ignite the air/fuel mixture. COMPRESSION TEST t See Figure 22 Before spending loo much time and money attempting to trace a problem to the ignition system, a compression check of the cylinder should be made. If the cylinder does not have adequate compression, troubleshooting and attempted service ot the Step 1 Step 2 00..7..P13 Fig. 22 Before any serious tasks are started, a compression check should be made. An acceptable pressure reading should be close to 90 psi (620.5 kPa) ignition or fuel system will lail to give the desired results of satisfactory engine performance. Breaker Points POINT GAP CHECK t See Figures 23 thru 28 1. If the points appear to be dirty or contaminated with oil or grease, open the points and insert a piece of notebook paper, close the points and pull the paper out. Repeat this using a clean piece of paper each time until the paper is clean between the closed points. 2. Inspect \he llywheel for cracks or other damage, especially around the inside Step 4 :r r ; 5-10 IGNITION AND ELECTRICAL SYSTEMS starter Spark plug lead 03575(;10 Fig. 23 Exploded drawing of a breaker point (magneto) ignition system, with major components identified Conlacl @ce.:.ed Correct Contact @area not centered Misalignment of centers Contact @area not centered point faces 03575GOO Fig. 24 Before setting the breaker point gap, the points must be properly aligned (top). Always bend the stationary point, never the breaker lever. Attempting to adjust an old worn set of points is not practical, when compared with the modest cost of a new set, thus eliminating this area as a possible cause of trouble. If a worn set of points is to be retained for emergency use, both contact surfaces of the set should be refaced with a point file ol lhe center hub. Check lo be sure that the metal parts have not become attached to the magnets. Verify each magnet has good magnetism byusing a screwdriver or other similar tooL 3. Thoroughly clean the inside taper of the lfywheel and the taper on the crankshaft !o prevent the flywheel from attempting to ·wa!k" on the crankshaft during operation. 035751'1.. Fig. 25 A normal set of breaker points used in a magneto will show evidence of a shallow crater and build-up alter a few hours of operation. The left set of points is considered normal and need not be replaced. The set on the right has been in service for more than 450 hours and should be replaced 03575P15 Fig. 26 The flywheel on a single cylinder powerhead has a "window" to permit point gap adjustment using a screwdriver and feeler gauge, as shown IGNITION AND ELECTRICAL SYSTEMS 5-11 Fig. 27 Breaker point assembly Base 051.2 4. Check the top seal around the crankshafl to be sure no oil has been leaking onto the stator plate. If there is any evidence the seal has been leaking,it must be replaced. ... 5. Test the stator assembly to verify it is not loose. Attempt to lift each side of the plate. There should be little or no evidence ol movement. 6. lightly lubricate the cam wick with all-purpose lubricant. Excess lubricant will shorten the breaker point life. Inadequate lubrication will quickly wear the rubbing block from the point set and thus alter the liming. Therefore, just use a dab of lubricant. 7. Unfortunately,the breaker point set is located under the flywheel. This location requires the hand rewind starter to be removed and the flywheel to be "pulled"in order to replace the point set. However, the manufacturer made provisions lor the point gap to bechecked with a feeler gauge through oneof two slots cut into the top of the flywheel lor this purpose. Therefore. only the hand rewind starter needs to be removed to perform the task of point adjustment.B. Rotate the flywheel to position the high point on the cam againstthe rubbing block of the breaker point assembly. 05195G03 ,r Fig. 28 The point gap needs to be checked using a feeler gauge. The point gap measurement should be 0.012-{1.016 in. (0.3-0.4 mm) ' ·Step 2 Step 3 9. If necessary, loosen the adjustment screw and reposition the breaker point base to obtain the correct point gap. 10. Verifiy that the felt pad is making light contact with the cam. The felt pad should be moistened with oil. REMOVAL & INSTALLATION • See accompanying illustrations 1. Remove the three bolts securing the hand rewind starter to the powerhead. lilt. the hand rewind starter free. 2. loosen the three bolts securing the -rope cup to the flywheel. A strap wrench or large pair of channel lock pliers around the outside edge of the rope cup may be needed to hold the flywheel while loosening the rope cup bolls . .-when a point set is new, the fixed contact point surface is a hemispherical curve. The movable contact point surface is flat to aid in adjusting the point gap. The manufacturerstates il ls permissible to file the curved surface flat if the points are pitted. This can be accomplished with a small flat file through the opening in the flywheel. 3. Removethe three bolts from the rope cup. lift offthe rope cup and flywheel cover (if equipped) free from the flywheel. 4. Hold the flywheel steady with a flywheel holder and remove the flywheel unit. ** WARNING Neverattemptto use a puller,which pulls on the outside edge of the flywheel. Step 4 ' '·· 5-12 IGNITION AND ELECTRICAL SYSTEMS Step 5 Step 12 5. Ontain a flywheel puller. Install the puller and take up the slack. Continue to tighten the puller and at the same time, shock the crankshaft with a gentle to moderate tap with a hammer on the end ol the puller. Tills shock will assist in oreaking the llywheel loose from the crankshaft. 6. lift the f!ywheel lree of the crankshaft. Remove and save the Woodruff key !rom the recess in the crankshaft. 7. Remove the nut securing the condenser and coil leads to the point set. PI)' off the circlip securing the point set to the pivot. Remove the adjusting screw and lift the point set free of the stator plate. II installing a new point set, remove the screw securing the condenser and lift the condenser from the stator plate. ,.It is considered good shop practice to replace the condenser when· ever a new point set is being installed. To install: 8. Install a new condenser and secure it to the stator plate with a screw through the mounting bracket. 9. Install a new point set. Install the adjusting screw but do not tighten it at this time. 10. AI ign the slot in the set with I he slot in the stator plate as a preliminary adjustment. Tile point gap will be set when the rubbing block contacts the flywheel cam. 11. Attach the coil and condenser leads to the point set. Install the circtip on the pivot post. 12. Place a tiny dab of thick lubricant on the curved surface of the Woodruff key to hold it in place while the llywheel is being installed. Press the Woodruff key into place in the crankshaft recess. Wipe away any excess lubricant to prevent the fly· wheel from "walking" during powerhead operation. 13. Check the flywheel magnets to ensure they are free ol any metal particles. Double-check the taper in the flywheel hub and the taper on the crankshaft. to verily they are clean and contain no oil. 14. Slide the flywheel down over the crankshaft with the keyway in the flywheel aligned with the Woodruff key in place on the crankshaft. Rotate the flywheel counterclockwise to be sure it does not contact any part of the stator plate or wiring. 15. Slide the washer onto the crankshaft. and then thread the flywheel nut onto the crankshaft. Using a flywheel holder, tighten the flywheel nut to 30 ft. lbs. (40.6Nm). 16. Position the flywheel cover (il equipped) and rope cup aligning the boll holes with the flywheel. Install the three bolls and tighten them securely. 17. Install the hand rewind starter to the powerhead. Tighten the three attaching oolts to 50 inch fbs. (5.6 Nm). 18. Install and tighten the spark plug to 20 ft. ltls (27 Nm). Attach the high-tension lead to the spark plug and close the access-cover door. 19. Install the cowling. On 1990 2.5 and 3hp powerheads, position the cover over the latches and push down until the latch engages. On 1991 and later 2.5, 3 and 3.3hp powerheads, posiiion and align the top cover over the bottom cover and engage the latches on both sides. Step 18 Condenser TESTING 1. The condenser does not have to oe removed to perform this lest 2. Place a mullimeler test lead on the condenser output wire and another on the condenser body. The meter should read 0.22...28 microfarads. 3. If the condenser measurement does not meet specifications, it may oe faulty and will need to be replaced. REMOVAL & INSTALLATION 1. Remove the three bolts securing the hand rewind starter to the powerhead. Lift the hand rewind starter tree. 2. Loosen the three oolts securing the rope cup to the flywheel. A strap wrench or large pair of channel lock pliers around the outside edge of I he rope cup may oe needed to hold the flywheel while loosening the rope cup oolls. ,.When a point set is new, the fixed contact point surface is a hemi· spherical curve. The movable contact point surface is flat to aid in adjusting the point gap. The manufacturer states it is permissible to file the curved surface flat ifthe points are pitted. This can be accomplished with a small flat file through the opening in the flywheel. 3. Remove the three oolls from the rope cup. lift off the rope cup and flywheel cover (if equipped) lree from the flywheel. 4. Install a llywheel holder and hold the llywheel steady while removing the flywheel unit ** WARNING Never attempt to use a puller, which pulls on the outside edge of the flywheel. 5. Install a flywheel puller onto the flywheel and take up the slack on the tool. Continue to lighten on the puller and at the same lime. shock the crankshaft with a gentle to moderate tap with a hammer on the end of the puller. This shock will assist in "breaking" the flywheel loose from the crankshaft. 6. lift the flywheel free of the crankshaft. Remove and save the Woodruff key from the recess in the crankshaft. 7. Remove the nul securing the condenser and coil leads to the point set and remove the condenser lrom the stator plate. ,.It is considered good shop practice to replace the condenser whenever a new point set is being installed. :r IGNITION AND ELECTRICAL SYSTEMS 5-13 To install: 8. Install a new condenser and secure it to the stator plate with a screw through the mounting bracket. 9. Attach the coil and condenser leads to the point set. Install the circlip on the pivot post. 10 .. Place a tiny dab ol thick lubricant on the curved surface of the Woodrulf key to hold it in place while the flywheel is being installed. Press the Woodrufl key into place 1n the crankshaft recess. Wipe away any excess lubricant to prevent the flywheel from "walking" during powerhead operation. 11. Check the flywheel magnets to ensure they are free of any metal particles. Double-check the taper in the flywheel hub and the taper on the crankshaft to verily they are clean and contain no oil. 12. ..ow, slide the llywheel down over the crankshaft with the keyway in the flywheel aligned w1th the Woodrulf key in place on the crankshaft. Rotate the flywheel counterclockwise to besure il does not contact any part of the stator plate or wiring. 13. Slide the washer onto the crankshaft and then thread the lfywheel nut onto the crankshaft. Hold the flywheel with a flywheel holder and tighten the flywheel nut to 30 ft. lbs. (40.6 Nm). 14. Position the flywheel cover (if equipped) and rope cup aligning the bolt holes with the flywheeL Install the three bolls and tighten them securely. 15. Install the hand rewind starter to the powerhead. Tighten the three attaching bolts to 50 inch lbs. (5.6 ..).16. Install and tighten the spark plug to 20 ft. lbs. (27Nm). Allach the high-tension lead to the spark plug and close the access-cover door. 17. lnslait the cowling. On 1990 25hp and 3hp power heads. position the cover over the latches and push down until the latch engages. On 1991 and later 2.5, 3 and 3.3hp powerheads, position and align the top cover over the bottom cover and engage the latches on both sides. Primary Coil TESTING t See Figure 29 1 . Connect the positive multimeter lead to the primary coil lead and the negative lead to the coi I ground.Meter should read 1 .5 ohms. 3. If the reading does not meet specifications, replace the coil. REMOVAL & INSTALLATION 1. Remove the three bolls securing the hand rewind starter to the powerhead. Lift the hand rewind starter free. 2. Loosen the three bolts securing the rope cup to the flywheel. A strap wrench or large pair of channel lock pliers around the outside edge ol the rope cup may be needed to hold the flywheel while loosening the rope cup bolts. 3. Remove the three bolts !rom the rope cup. Lift off the rope cup and flywheel cover (if equipped) free from the flywheel. 4. Hold the flywheel steady with a flywheel holder and remove the flywheel unit. OSI!l5.. Fig.29 Use a multi meter to test the resistance of the primary coil ,..Never aHempt to use a puller, which pulls on the outside edge of the flywheel. 5. Install the puller onto the flywheel and then take up the slack on the puller. Gonlmue to lighten the puller and at the same time, shock the crankshaft with a gentle to moderate tap w1th a hammer on the end cl the puller. This shock will assist in "breaking• the flywheel loose from the crankshall. 6. Lift the flywheel free of the crankshaft. Remove and save the Woodrulf key from the recess in the crankshaft. 7. Remove the screws securing the primary coil to the stator plate and remove the primary coi I. To install: 8. Install a new primary coil and secure it to the stator plate with the fastening screws. 9. Place a tiny dab ol thick lubricant on the curved surface of the Woodruff key to hoi.. it in place while the flywheel is being installed. Press the Woodruff key into place 111 the crankshaft recess. Wipe away any excess lubricant to prevent the flywheel from "walking· during powerhead operation. 10. Check the flywheel magnets to ensure they are free ol any metal particles. Double-check the taper in the flywheel hub and the taper on the crankshaft to verily they are clean and contain no oil. 11. Now, slide the flywheel down over !he crankshaftwith the keyway in the flywheel aligned with the Woodruff key in place on the crankshafl. Rotate the flywheel counterclockwise to be sure itdoes not contact any part clthe stator plate or wiring. 12-Slide the washer onto the crankshaft. and then thread the fi)'Hheel nul onto the crankshaft. Hold the flywheel with a flywheel holder and tighten the flywheel nut to 30 ft. lbs. (40.6 Nm). 13. Position the flywheel cover (if equipped) and rope cup aligning the bolt holes w1th the flywheel. Install the three bolts and lighten them securely. 14. Install the hand rewind starter to the powerhead Tighten the three attaching bolts to 50 Inch lbs. (5.6 Nm). 15. Install and tighten the spark plug to 20ft. lbs. (27 Nm). Attach the high-tension lead to the spark plug and close !he access-cover door. 16. Install the cowling. On 1990 2 5 and 3hp powerheads, position the cover over the latches and push down until the latch engages. On 1991 and later 2.5 3 and 3.3hp powerheads, position and align the top cover over the bottom cover and' engage !he latches on both sides. Ignition Coil TESTING An multimeter test can only detect certain faults in lhe secondary ignition coil. Replace the ignition coil ii the multimeter reading is not as specified. If the coil tests satislactory and the coil is still suspected of being faulty, use a magneto analyzer to thoroughly check the coil. Follow the coil test procedure in the analyzer manual. The primary and secondary coil resistance tests may be performed with the components installed on !he powerhead. If chaffing or broken wiring is suspected, removal of the component is recommended to permit a complete inspection of all wiring leads. Primary Resistance t See Figure 30 1. Disconnect the primary coil electrical lead Black/White wire Irom the bullet connector on the side of the powerhead. Remove the two screws securing the stator plate to the powerhead. 2. Lift up on the stator plate and slowly feed the primary coil wire lead through the opening in the powerhead. Set the stator p!ate aside for bench testing. 3. Obtain a multimeter and set il on the Rx 1 scale. Connect I he (+) meter lead to the coil Black/Wnite lead. Connect the (-) meter lead to a good coil ground 4. An acceptable resistance reading for the primary coil is 1.5 Ohms. 5. If the reading is not within an acceptable range, the prima1y coil is defective and must be replaced. Secondary Resistance • See Figure 31 ,-11 not previously done, disconnect the lead on the secondary ignition coil at the bullet connector and remove the high-tension lead from the spark plug. 1. Remove the two mounting bolts securing the coil to the powerhead and set the coil aside lor bench testing. 5-14 IGNITION AND ELECTRICAL SYSTEMS 05195COS 1 CAPACITOR DISCHARGE IGNITION (CDI) SYSTEM Description and Operation -Yellow ldcnlifica.Don OOIJ5003 Fig. 30 Connect the positive (+) meter lead to the coil and the nega tive (-) meter lea..to the coil ground. The meter reading should be .81-1 .09 ohms REMOVAL & INSTALLATION II not previously done. disconnecllhe lead on the secondary ignition coil at the bullet connedor and remove the high-tension lead from the spark plug. t See Figure 32 The engine's flywheel contains magnets carefully positioned to create an electric current as theyrotate past specially designed coils ol wire. Current is created by magnetic induction. Simply put. that means that amagne! moving rapidly near a conductor will Induce electrical flow within the conductor. Conversely, a wire that moves rapidly through a magnetic field will also generate electrical now This principle governs lhc working of electric motors. alternators and generators. One or the coils under your flywheel is called a charge coil. As the flywheel magnels spin past this coil. they generate in it a fairly high-voltage alternating current lhatlravels to your system's 'modute• otten called lhe power pack or CDI unit. This voltage Is allen ln the region ol 200 volts AC. The other ignition system coil(s) found under the flywheel are called the sensor coils, pulsar coils or trigger coils. They send an electrical signal to the ignition module totell it which cylinder lo work with at the correct lime. TheCDI unlt is the brains ol lhe system and serves several functions. First. it converts I he alternating cunenl (AC) fromthecharge coil lnto usable direct current (DC). Next It stores lhe current In a built-in capacitor. The module also interprets !he limingstgnal lrom the trigger coil. This changes constantly with engine speed and moving the trigger coil's posillon relative to the flywheel magnets brings about the change. Thecoil's movement is colllrolled by a device called a liming plate, to which hath thecharge coil and lr!gger coils are mounted. Theliming plate moves inresponse to changes In throtUe opening. to which it is mechanlcally linked. The CDI unit also controls the discharge ofthe capacitor and sends this voltage to lhe primary winding of tile Ignition coif for the correct cylinder. Also (depending on the system) the module may incorporate electronic circuits Ihal limit engine speedand prevent over-revving. Some rrodules even have a circuit that reduces engme speed it !he engine begins toruntoo hot lor any reason. Larger enginesallen havean automatic ignitionadvancelor initial start-up and for when !he engine is running at temperatures less than approximately 100°F. rv<.anulacrurers commonly use one power pack or module for each bank ofcylinders on V-lype powerheads. One module will control the odd numbered cylinders and the other will service the even numbered cylinders. The voltage trom the module goes to theprimary winding of the ignllion coil or high-tension coif. You may know this type of coil as a step-up transformer. Here, the voltage is stepped up to between 15,000 and 40,000 volts Thafs the 'kind ol voltage needed to jump the air gap on the spark plug and ignite the air/fuel mixture in the cylinder. Your high-tension ignition coil has two sides, Ihe primary side and the secondary side. It Is really two coil assemblies combined into one neat compact case. 051'l5f.C6 Fig. 31 Connect the (+) meter lead to the spark plug lead terminal and the negative (·) to the coil ground. The meter reading should be 4.250-5.750 ohms 2. Remove the two mounting bolts securing the coil to the powerhead and set lhe coil aside lor bench tes!ing. To3. Install: Install the two bolts securing the coil to lhe power head and lighten snugly. 4. Aftermaking sure the both sides of the connector is clean. reconnect the bullet conneclor making sure if's tight. 5. tnslall lhe spark plug wire Fig. 32 Functional wiring diagram of the Thunderbolt CD Ignition system. The boxes are stacked one on top of the other, so they must be separated to gain access to the inner box :r ,•.. IGNITION AND ELECTRICAL SYSTEMS 5-15 The internal construction of a typical ignition coil includes primary and secondary windings. It also uses the principle of magnetic induction with the magnetism generated bythe primary (lower -voltage) winding creating a magnetic field around the secondary winding, which has many more windings than the primary coil. The ignition module controls the rapid turning on and oH of electrical flow in the primary winding, thereby turning this magnetic field on and off. The rapid movement of this magnetic field pasl lQe secondary windings induces electrical current flow. The are greater the number of turns of wire in the secondary winding, the higher the voltage produced. As this secondary voltage leaves the center tower of the ignition coil, it travels along the spark-plug wire, which is heavily insulated and designed lo carry this high voltage If all is well, the high voltage will jump the gap on the spark plug between the center electrode and the ground electrode. On larger engines with surface-gap plugs, the high voltage current will jump from the center electrode to the side of the plug assembly itself. completing a circuit to ground via the engine block. Last but certainly not least, is the stop control. You need a means to shut your engine off and a good way is to stop I he spark plugs from working. Depending on your engine. this may be accomplished by a simple stop button or a key switch on larger engines. This disables !he whole ignition system. On newer engines, an emergency stop button with an overboard clip and lanyard attachment is standard. This system is wired directly inlo·lhe ignition module. It functions by creating a momenlary short circuit inside lhe CDI unit, grounding the current intended lor !he high-tension coils and thus shutting off the ignition long enough to stop the engine. Faulty stop circuits are frequently the cause of a no spark condition. 2.5-3.3 HP The components of this system include a flywheel and magnets, capacitor charging/t rigger coil, COl, secondary ignition coil, slop switch and spark plug. Four magnels are imbedded within the flywheel. These magnets are arranged in pairs in a North/South and South/North polarity position 180°apart. As the North/South magnets pass over the capacitor charging/trigger coil, located under the llywheel on the stator plate. a magnetic field is buill up within the capacitor trigger/coil windings, producing an AC voltage. This voltage is conducted to the CDI where it is rectified and stored in a capacitor within the CDI. As the opposite polarity magnets, South/North pass over the capacitor charging/lrigger coil, a triggering voltage (pulse) is generated and sent to the CDI. The bias/trigger circuit releases the stored voltage from the capacitor to the secondary ignition coil. The secondary ignition coil steps up the voltage through the internal primary and secondary windings to a voltage level where it can jump the gap at the spark plug. The Ignition coil fires the spark plug at both the top of the piston stroke and at lhe bottom of the stroke or every 180 degrees of crankshaft rotation. One !iring results in work-the other is a free ride. There are no mechanical devices for timing adjustments or timing advancement throughout the throttle range. When the slop switch on the tiller handle is actuated, the bias/trigger circuit within the CDI is shorted to ground. This prevents the capacitor within the CDI from discharging the stored vo!lage to !he secondary ignition coil and firing the spark plug. The powerhead is shut down. The manufacturer makes lhe following suggestion: If the powerhead will not idle to-say a good trolling speed but runs excessively fast with the throttle fully closed-the bias/trigger circuit within the COl is defective and the CDI must be replaced. 4-275 HP ** CAUTION On all powerheads equipped with a flywheel magneto, the rectifier will be damaged if the battery leads are disconnected from the battery while the powerhead is running or if the leads should accidentally be reversed. This is a safety feature designed by the manufacturer because the cost of replacing a rectifier is a fraction of the cost for a new switch box. This CD ignition system is an alternator driven capacitor discharge system. Major components include the flywheel, stator coil, trigger coil, switch box, ignition coils (one per cylinder) and of course the spark plugs (one per cylinder). The flywheel contains three sets of permanent magnets mounted on its inside surface. The outer rim contains two sets ol magnets and the center hub has one set. The stator is mounted under the flywheel and has both a low Speed (LS) and a HighSpeed (HS) capacitor-charging coil. As the flywheel rotates, the permanent magnets on the rim surface pass over the LS and HS capacilor charging coils which produce an AC voltage. The AC voltage is conducted to the switch box where it is rectified and stored in a capacitor. The trigger assembly is also mounted under the flywheel-in the center of the stator and contains the trigger coil. On a 4hp or 5hp powerhead, the trigger is mounted inside the "pan" under the flywheel. On all other powerheads with this type ol lgnition, the trigger is mounted on a stator plate around the crankshaft under the llywheel. As the inner magnets of the !!ywheel pass by the trigger coil, an AC pulse is produced. This pulse voltage is also conducted to the switch box where it turns on one ol two electronic switches or Silicon Controlled Rectifiers (SCR) in the switch box. A posiiive vollage pulse turns on the SCR switch for cylinder No. 1, a negative voltage pulse turns on the SCR for cylinder ..Q. 2. As each SCR switch closes, the stored capacitor voltage is discharged to the primary side of the ignition coil for the respective cylinder. The ignition coil steps up the vollage level to a value high enough to jump the spark plug gap and ignite the compressed air/fuel charge in the cylinder. Spark timing is advanced and retarded on the 6-25hp models by rotating the !rigger coil stator assembly. As the trigger coil stator assembly is rotated this changes the phase relationship between the trigger magnet poles and trigger coils, which will advance or delay the opening and closing of the SCR's in the switch box. advancing or retarding the ignition liming. When the stop switch is actuated, the voltage produced by the stator LS and HS coil is shorted directly to ground within the COl. This short circuit action prevents the ignition coils lrom firing the spark plugs and causes the powerhead to shut down. Troubleshooting the CDI System TROUBLESHOOTING WITH MINIMAL TEST EQUIPMENT .-The following conditions apply to all powerheads covered in this manual. Troubleshooting procedures are courtesy of our friends at COl Electronics (256-772-3829). • Intermittent Firing:-This problem can be very hard to isolate. A good inductive tachometer can be used to compare the RPM on all cylinders up through wide open lhrottte. A big diHerence on one or two cylinders indicates a problem. • Two or more cylinders misfiring:-It is recommended that both p01ver packs be replaced, unless the problem is caused by a bad trigger. • Engine continuously blows power packs:-When an engine starts blowing packs repeatedly, especially on the same cylinders, replace the ignition coils on those cylinders. The inductive kickback from a bad coil can destroy the packs, even if the coils check good with all known tests. A stator that tests good can also be sending spike voltages to the pack causing them to fail repeatedly. • Visually check the stator, trigger and flywheei:-Cracks,burned marks and bubbling on the stator or trigger indicate a severe problem. If the stator shows bubbling around the battery charge windings, more than likely you wi II have to replace !he rectifier/regulator in addition to the slator. Signs of rubbing on the flywheel usually indicate a bad upper or lower bearing. Check both the outer and trigger magnets for signs of cracking and to be sure that they are not loose. The !allowing conditions apply only to Mercury 6-Cylinder powerheads with AD! ignition: • No lire on 1,3,5 or 2,4,6:-Swap Red and Red/While wires, also Blue with blue/White wires. If the problem moves to lhe other sel of cylinders. the stator is likely at fault. Disconnect rectilier and retest. If the engine fires normally, replace the rectifier. If no change, we recommend replacement of the slator. If you replace the stator and the problem remains. try another flywheel, if possible. • No lire on one cylinder:-Since !his condition can be caused by the opposite switch box (pack), disconnect the White/Black jumper between the packs and retest. If the dead cylinder starts firing, replace the pack that was !iring all three cylinders. As a verification, swap the trigger and spark plug wire to the cylinder closest to the dead cylinder. If the problem moves to #3, replace the opposite power pack (switch box). If #1 is still dead, swap the green and green/While coil wires. If the problem moves to #3, replace the power pack (switch box). .-Remember to put the trigger wires in the correct order after you finish. • Always check the bias circuit:-Disconnect the jumper between the packs on the While/Black post. Check the resistance from the While/Black post on each pack to engine ground. Standard packs will read from 1300(H 5,000 ohms. Make sure thai the bias reading is the same on both packs. .-tithe bias is out of specification on one pack you must replace both packs to prevent future damage. This circuit effects ignition liming and could cause a powerhead failure. 5-16 IGNITION AND ELECTRICAL SYSTEMS TROUBLESHOOTING BATIERY CO IGNITIONS ** CAUTION Do not use a maintenance free battery with these types of ignitions as they tend !O overcharge and blow the packs. ,.A large portion of the problems with the battery CD units are caused by low battery voltage or bad ground connections or high battery volt· age. low Voltage symptoms are weak lire or weak erratic liring of cylln· ders. Misfiring after a lew minutes of running can be caused by excessive voltage at the pack. Battery reversal will usually destroy bat· tery, CD units and triggers. ** WARNING Check the voltage on the Red (or Purple) wire at the CD unit through the RPM range. At no time should the voltage exceed 15.5 Volts DC. The first item to check is that all battery and ground connections are solid. • Dead or No Fire Until You Release the Key Switch:-Oisconnect mercury switch and retest , if the engine fires. replace the mercury switch. Check the voltage on the Red and White ignition wires at the CD unit. If the voltage is less than 9% volts during cranking there is a problem in the battery wires or ignition switch circuit. These units require at least 9'12 volts to fire properly. Perform a peak voltage check between the White and Black wires (sometimes Black and Blue).Reading should be at least 2% at cranking. Connect a jumper wire directly from the battery positive (+) terminal to the White Ignition wire and retest. II the engine still fails to crank. recheck voltage as above. If low. replace battery and retry. ** CAUTION Do not connect the jumper wire to the White trigger terminal. In order to kill the engine if it cranks, the jumper wire has to be dis· connected and/or choke the engine. If there is still no lire, disconnect trigger wires and connect a CD tester. Align the rotor with a spark plug wire. Connect a spark gap tester to all spark plug wires and turn the ignition switch ON. II the CD unit fires to only one spark plug wire, check points wire (for breaks and shorts) or trigger. If any other spark plug wire fires besides the one the rotor is aligned with, the distributor cap and rotor should be replaced. li the CD unit fails to lire with this hookup, it is usually bad. Check the trigger using a trigger tester to see if it is good or bad. • Engine Cranks and Fires As long As The Starter Is Engaged:-This problem usually indicates a bad trigger. • Check the Ignition Coii:-An open, cracked or poorly grounded coil can burn out a battery CO. • Check the Peak Voltage on the Primary Input Wire to The Coii:The reading should be approximately 100 volts or more for OEM units and 200 volts aftermarket units. • Inline engines with internal exhaust plate:-lf engine speeds up when you remove one spark plug wire. the internal exhaust plate is more than likely warped. TROUBLESHOOTING ALTERNATOR DRIVEN IGNITIONS ,.Initial peak voltage readings should be taken with everything hooked up. • Disconnect the kill wire:-Connect a mu!timeter between the kill wires and engine ground. Turn lhe ignition switch ON and OFF several times. If at any lime, you see DC voltage on the kill wires, there is a problem with the harness or ignition switch. Battery voltage on the kill circuit will destroy most CD units. • Visually Inspect Stator for Cracks or Varnish leakage:-lf found, replace the stator. Burned marks or discolored areas on the battery charge windings indicate a possible problem with the rectilier. • Unit Will Not Fire: Disconnect kill wire at the pack:-Check lor broken or bare wires on the unit, stator and trigger. Check the peak voltage of the stator. (on 3and 6-Cylinder models read from each Red and Blue wire to engine ground. On 4-Cylinder engines, read between the two Red wires and between the two blue wires), with everything connected. The readings should be approximately 180 volts or more on the Blue wires and 30volts or more on the Red wires. Disconnect the rectifier. If the engine fires, replace the rectifier. • Engine Will Not Kiii:-Check kill circuit in the pack by using a jumper wire connected to the Black/Yellow terminal or wire coming out of the pack and shorting it lo ground. If this kills the engine. the kill circuit in the harness or on the boat is bad. possibly the ignition switch. • High Speed Miss:-Disconnect the rectilier and retest. It miss is gone, the rectifier is usually at fault. II the miss still exists, check peak vollage (between the Red wires on 4-Cylinder, or Red wires to engine ground on 3 & 6-Cylinder) ol the stator at high speed. ·,- use caution when doing this and do not exceed the rated voltage range of your meter. The readings should show a smooth climb in volt· age. If there is a sudden or fast drop in voltage right before the miss becomes apparent, the stator is usually at fault. If there is no indication of the problem, it could be a small water leak in one or two cylin· ders. • Coils Fire with Spark Plugs Out but Not ln:-Gheck for dragging starter or low battery causing stow cranking speed. Test peak voltage on Ihe stator and trigger. Disconnect rectifier, regulator and retest. If the problem goes away, replace the rectifier and/or regulator. • Engines Runs Rough on Top or Bottom Two Cylinders (4-Cylinder Engines):-Check peak voltage of the stator belween Blue wires and ground. Readings to ground should be fairly equal. If unequal, swap slator leads (Blue with Blue/White, Red with Red/White) and see if the problem moves with the slator leads. II it does. replace the stator. Check trigger resistance between 11 & 12. compare to resistance between 13and #4. The readings should be approximately 850-12,5091 ohms. For test purposes only, swap trigger leads 1 & 3,and 2 & 4. If the problem moves. replace the trigger. If i! does not move. swap coil primary wires. and replace the pack illhe problem remains on the same terminals. • No Fire on One Bank (Odd or Even Cylinders on lnline 6-Cylinder Engines):-Gheck peak voltage of the stator, checking from each red and blue wire to engine ground. The readings should be approximately 180 volts or more on the blue wires and 30or more on the red wires. If a OVA meter is notavailable,swap both sels of the stator wires between the packs. If the problem moves. replace the stator. II the problem stays on the same bank. swap physical location and all connections of the two packs. If the problem stays with one pack, replace the pack. ,-If the pack is bad, it is recommended that both packs be replaced. If the packs lose ground, internally or externally, the packs usually have severe damage to the bias circuit and need to be replaced as a set. Packs manufactured by COl Electronics (256-772-3829) will withstand loss of ground connection, normally with no damage to the bias cit· cuitry. In most cases you will just lose fire. • Intermittent Firing On One or More Cylinders:-Disconnect the White/Black wire between the packs on a 6-Cylinder and retest. If all cylinders now fire,replace both packs as there is a problem in the bias circuitry. On all others, check for low vollage from the slator and trigger. Disconnect the rectifier and retest. II the problem disappears. replace the rectifier. • All Cylinders Fire but the Engine Will Not Crank and Run: -On 3 and 6-Cylinder engines, disconnect While/Black wire and check the bias circuit (White/Black terminals) resistance lo engine ground. Readings should be approximately 15,000 ohms If the readings are correct on the packs, index the flywheel and check timing on all individual cylinders. lithe timing varies. replace the packs On 4Cylinder engines the bias circuit is internal, therefore the only way to verify proper operation of the bias, circuit is to index the flywheel and check timing on each cylinder. If the timing is off, replace the packs. Trigger (Charge) Coil TESTING The following tests perform a resistance check of both the capacitor charging and trigger coils. This test is performed with the components installed but disconnected at the wire lead bullet connectors. It is essential that the wires be disconnected in order to obtain an accurate reading and evaluation of the components. If the coils should test bad, before spending the money on new replacement coils, perform the test a second time alter the unit has been removed from the powerhead to verify the coil is bad. ' ·IGNITION AND ELECTRICAL SYSTEMS 5-17 ** WARNING Do not rotate the flywheel during these tests or damage to the multimeter will result. Resistance Tests • See Figure 33 1. Label and disconnect the trigger coil wires. 2. Connect the multimeter leads to the wires specilied in the •Ignition Testing Specifications· chart. 3. Notethe resistance reading. Resistance should be within specilications listed in the "Ignition Testing Specifications" chart. ,..Resistance readings are temperature sensitive. The specifications given are for components at 68"F (20•C). If temperature is higher or lower, resistance readings may be off slightly. 4. If resistance is not within specilication, remove the trigger coil and retest. If readings are similar, the trigger coil may be detective. 5. Disconnect the multimeter. 6. Connect the coil wires as previously labeled. Direct Voltage Adapter Tests • See Figures 34, 35, 36, 37 and 38 1. Remove a li the spark plugs. 2. Install a spark plug gap tool to each spark plug boot and attach the alligator clips to a good engine ground. 3. Disconnect the powerhead lrom its fuel supply. 4. Locatethe trigger/charge coil. 5. Therearetwo ways to connect a multimeter with peak reading adapter to the trigger/charge coil harness. Thefirst is to use a factory style wiring harness adapter. These adapters can be obtained from your Mercury dealer. The second way is to use piercing probes available from tool manufacturers. 051951'08 Fig. 33 Use the multimeter to check the trigger coil resistance. The trigger coil does not need to be removed to perform this test 05196POS Fig. 34 A COl Electronics peak reading voltage adapter (#511-9n3) plugged Into Fig. 35 Using a mullimeter and OVA a.ttachment to check the peak voltage on the trigger/charging circuit COl Stator Trigger (2fJ-25) 2 398-8778 174·8778K1 1991·95 1 4·8778KI(50.55.50) 1994-97 39U778 (75·90) 1994·97 174-8778K1 (75-90) 3 174-9710K1 4 ($p¢<1Jel) 4 a high quality multimeter Charge Coli Ohms High Speed - Trigger High Speed - 160V! CO Mo ule (S itch Box) Trigger Wire Testing Charge Coil Wire Testing B1oR W/Bto VI Grotr.d(B)to R WIBtoW RtoRIW 1'118 10\V RtoRIW W/BtoW Groond (B) 1 R W/ toW RI<>RIW WIBioBt BltoBINI YI/BtoB BrloB (!WI) 8r1o8 (8/W) 174•97l(JI.I .. 1900-00 {9-15emp) 6 t;oo. Br(B sleew) P(Y sleeve) 10 w ( sleeve) und (B)IDR and RJW 5-18 IGNITION AND ELECTRICAL SYSTEMS Charge Colt Charge Colt CD Modut. CDI Sllllor Trlgge< Trigger OVA (Swflch Box) Trigger WireTesting Charge Coli WireTesllng tn $1111ors-1hnd31M710 ...__ l>\'UieMfi"")'..-KJ 51Jioriii:ITrlggat'OadlnQI_Oit_"llhoo•..,.d...,;,.... 05195Ai'l Fig. 36 High quality piercing probes (1!511·9770), like those available from CDI E.lectronlcs (256·772·3829), allow you to perfonn dynamic Ignition testing without the use of factory wiring harness adapters Fig. 37 The tiny pins In the piercing probes contact the wires to read res is· tance or voltage . 6. Connect the mullimeter to the trigger coil wires listed in the "lgnllion Testlng Specifications• chart. 7. Use the slllrter motor 01 recoil starter to crank the ,.If il ls not possible to obtain a Clilnking speed high enough to properly test the trigger coli, the engine can be tested in the same manner while running. 8. Note lhe cranking voltage and compare it to the voltage listedin the "Ignition Testin Specifications· chart 9. If voltage Is below specillcation. lhe trigger/charge coil may be faulty. 10. If voltage Is above specification, the COl unit should be tested. 11. Disconnect the multime!er with peak reading adapter. REMOVAL & INSTALLATION 2.5-3.3 HP • See accompanying Illustrations 1. Remove the cowling. 2. Remove the three bolls securing the hand rewind starter to the power head. un ofl the hand rewind starter from the powerhead. Step 2 Fig. 38 ... but do not destroy the insula· lion on the wire '{ IGNITION AND ELECTRICAL SYSTEMS 5-19 Step 5 Step 8 Step 11 3. Loosen the three bolts securing the rope cup to the flywheel. A strap wrench or large pair ol channel lock pliers around the outside edge of the rope cup may be needed to hold the flywheel while loosening the rope cup bolts. 4. Remove the three bolts from the rope cup. Lilt on the rope cup and flywheel cover (if equipped) free ot the llywhee1. 5. Installa llywheet holder and hold the flywheel steady while removing the flywheel nut. 6. An alternate method may be used to remove the llywheel nuL Install a grade liveor stronger bolt into one of thellywheel puller bolt holes. Insert a pry bar between the boll and deep socket on the flywheel nut. Using the pry bar as a lever, remove the !lywheel nut from the llywheel. 7. Obtain a flywheel puller tool as illustrated. 8. Analternate method of preventing the flywheel from rotating, is to use a bolt and a pry bar as Illustrated . .-Never attempt to use a puller that pulls on the outside edge of the flywheel. This action will result In a bent, dist.orted or possibly even broken flywheel, a damaged flywheel must be replaced. 9. Installa llywheel puller. Attach the proper size wrench onto the end of the puller tool threaded shaft. Rotatethe wrenchin a cloclcwise direction, conlinue to tighten on the special tool and at the same time, shock the crankshaft with a genl!e to moderate tap with a hammer on the eod olthe puller. This shod< will assist in "breaking"theltywheettoose from the crankshall 10. When the flywheel has broken loose from the crankshaft taper fil remove !he llywtleel putter tool and lilt the ftywheel from the powerhead. 11. Remove the lour screws from lhe port side of the lower cowling cover and remove the cover from the powerhead. 12. Disconnect the lead from the capacitor charging{lrigger coil at the bullet connectoronthe port side of the powerhead. 13. Remove the screw and clamp on lop of the stator plate securing the lead to the capacitor charging trigger coil. Feed the wire up through the opening below the statorplate. Remove the two screws securing the capacitor charging trigger coil to thestator plate and lih off the free trigger coiL Screw (3 plcs) To install: Step 7 Step 12 03575P39 14. Feed the wire lead of the capacitor charging/trigger coil down through the opening below the stator plate. Position the charging/trigger coil onto the stator plate and secure wilh two screws. Connect the lead from the capacitor charging/trigger coil tothe lead trom thecor at the bullet connector on the port side of the powerhead. 15. Install the clamp onto the While lead ol the capacitor charging trigger coli at the stator plate and secure with the screw. Step 14 :r ..•.. 5-20 IGNITION AND ELECTRICAL SYSTEMS Step 16 16. Apply just a dab ol thick lubricant onto the curved surface ol the Woodrulf key to hold it in place while the flywheel is being installed. Press the Woodruff key into place in the crankshaft recess. Wipe away any excess lubricant to prevent the flywheel from "walking• during powerhead operation. 17. Check the flywt1eet magnets to ensure they are free of any metal particles. Double-check the taper in the flywheel hub and the taper on the crankshaft to verify they are clean and contain no oil. 18. Now, slide the flywheel down over the crankshaft with the keyway in the flywheel aligned with the Woodruff key in place on the crankshaft. Rotate the flywheel counterclockwise to be sure it does not contact any part of the stator plate or wiring. 19. Slide the washer onto the crankshaftand then thread the flywheel nut onto the crankshaft. Using a flywheel holder toot tighten the flywheel nut to 30 fl. lbs. (40.6Nm). Step 19 20. Positionthe flywheel cover (if equipped) and rope cup in place over the flywheel with the holes in the cover and cup aligned with the holes in the flywheel. Install and tighten the three bolts to 5.8 ft. lbs. (8 Nm). 21. lower the hand rewind starter onto the powerhead and align the mounting tabs on the starter with the powerhead. Tighten the three attaching bolts to 5.8 II. lbs. (8 Nm).22. Install the proper heat range spark plug into the powerhead. Tighten the spark plug to 20 II. lbs. (21.7 Nm). Install the top cowling onto the powerhead and secure it with the two snap latches. 23. Place the port side ot the lower cowling cover into position and align the holes in the cover with the powerhead. Secure the cover in place with the five mounting screws. Tighten the screws securely. 4-5 HP • See accompanying illustrations 1. Remove the cowling to expose the flywheel. 2. Disconnect the start in neutral only linkage This linkage must be disconnected before "pulling" the flywheel. 3. Remove the flywheel nul and washer (if equipped) from the end ol the crankshall. Aflywheel strap wrench may be required to hold the flywheel securely while the nut is loosened. Step 3 :r r•.. IGNITION AND ELECTRICAL SYSTEMS 5-21 Step 4 4. IIa strap wrench is not available.an alternate method is to use a bolt and pry bar to hold the flywheel. First. thread a5Aa in. bolt into one of the threaded flywheel holes. Position a pry bar between the boll and thesocket on the flywheel nut. Proceed to loosen and remove the flywheel nut. 5. Obtain the proper type flywheel puller. Never attempt to use a puller which pulls on theoutside edge of the flywheel or the flywheel may bedamaged. After the puller is installed.lighten the center screwonto the end of the crankshaft. Continue tightening the screw until the flywheel is released from the crankshaft. Remove the flywheel. 6. Remove the screw and wire clamp at the stator plate. 7. Disconnectthe coil leads I rom the CDI unit leads. 8. Remove the screws securing the capacitor charging coil and then remove the coil. To install: 9. Carefully route the charging coil leads along the statorplate and place the coil over the mounting bosses of the crankcase cover. 10. Apply a drop of thread-locking compound to the coil securing screws and torque them to 14 inch lbs. (1.6 Nm). 11. Secure the coil leads/sleeve, using the wireclamp and screw. Tighten the screw securely. 12. Connect the capacitor charging coil leads to the CD! unit leads. 13. Reinstall the flywheel assembly. Using a flywheel holder tool tighten the flywheel nut to 30 ft. lbs. (40.6 Nm). 14. Install the cowling. Step 5 6-25 HP • See Figure 39 1. Remove the cowling. 2. Removethe recoil assembly. 3. Remove the flywheel assembly. 4. Disconnect the stator and trigger coil wires. 5. Removethe retaining screw holding down the stator assembly. 6. Remove the trigger coil assembly from the powerhead. To install: 7. Install the trigger coil assembly onto the powerhead. 8. Install the stator assembly onto the powerhead above the trigger coil and lighten the retaining screws to 40 inch lbs. (4.5 Nm). 9. Clean and inspect the both the crankshaft and flywheel tapers for grease and damage. 10. Install the flywheel Woodruff key onto the crankshaft. 11. Install the flywheel assemblyand tighten the flywheel nut to 50ft. lbs. (67.8 Nm). 12. Reconnect the statorand trigger coil connectors at theswitch box. 13. Install the recoil assembly and tighten the retaining screws to 70 inch lbs. (7.9 Nm). 14. Install thecowling. 1 -Recoil Assembly 2 -Bolt (3)3 -Flywheel Nut 4 -Washer3j 5 •Flywheel 7 -Stator 6 -Screw (2)8 -Screw (Manual) 10 -Retainer (Trigger) Fig. 39 Exploded view drawing of the ignition system-+25hp 30 and 40 HP (2-Cylinder) • See Figures 40 and 41 1. Remove the cowling and flywheel cover. ()6195611 2. Hold the flywheel wilh a flywheel holder and remove the flywheel nut and washer. 3. Install the crankshaft protector cap (91-24161), then install the flywheel puller on the flywheel. 4. Hold theflywheel tooth with the wrench while tightening lhe bold down on the protector cap. Tighten the boll until lhe flywheel comes free. 5. Remove the flywheel. ,..Neither heat nor the use of a hammer should be used to aid in the removal of the flywheel. Damage to the electrical components underneath the flywheel may occur. 6. Disconnecl both the stator and trigger coil leads. 5-22 IGNITION AND ELECTRICAL SYSTEMS Oli95GI2 Fig. 40 Hold the flywheel with a flywheel holder and remove the flywheel nut and washer apply a small amount of thread-locking compound and tighten the retaining screws to 50 inch lbs. (5.6 Nm). 11. Clean and inspect the both the crankshaft and flywheel tapers lor grease and damage. 12. Install the llywheel Woodruft key onto the crankshaft. 13. Install the flywheel assembly and tighten the llywheel nut to 95ft. lbs. (129 Nm).14. Reconnect the stator and trigger coil connectors at the switch box. 41Hi0 HP (3-Cylinder) • See accompanying illustrations 1. Remove the flywheel cover from iiie engine. ** WARNING The engine could possibly start when you are turning the flywheel during removal and installation. Make sure to remove the spark plug leads from the spark plugs to prevent the engine from staring. 2. While holding the flywheel with a llywheel holder, remove the flywheel nut and washer. 3. Install the crankshaft protector cap (91-24161). then install a flywheel puller on the llywheel. 4. Hold the flywheel tooth with the wrench while tightening the bold down on the protector cap. Tighten the bolt until the flywheel comes free . .-Neither heat nor the use of a hammer should be used to aid in the removal of the flywheel. Damage to the electrical components underneath the flywheel may occur. 5. Remove the flywheel and flywheel key. 6. carefully inspect the ltywheel for cracks or defects. 7. Inspect the crankshall and flywheel tapers and key ways for wear and damage. 8. Check lor loose or damaged flywheel magnets (located in the outer rim and center hub). II necessary, replace the flywheel. 9. Remove the Yellow stator leads from the regulator/rectifier leads. 10. Disconnect all stator leads from the COl wiring harness. .-Removal of the ignition plate may be may be necessary to gain access to the stator leads. 7. Remove the stator retaining screws and remove the stator. 8. Remove the trigger coil assembly To install: 9. Install the trigger coil assembly onto the powerhead. 10. Next, install the stator assembly onto the powerhead above the trigger coil, a-Link Arm b-Trigger Step 13 Trigger Coil Step 14 11. Remove the screws and lilt the stator off the bearing cage. 12. Disconnect !he trigger coil leads from the CDI wiring harness. 13. Disconnect the link arm and remove the trigger. 14. Lift the trigger coil assembly off the bearing cage. To Install: 15. Install the trigger coil and connect the link arm. 16. Place the trigger on the bearing cage. 17. Route the lead wires unde.. the ignition plate and down to the CDI wiring harness. 18. Connect the corresponding trigger coil leads to the COl wiring harness. 19. Install the stator on the bearing cage. Apply a small amount of thread-locking compound and tighten the screws to 60 inch lbs. (6.8 Nm). 20. Connect the Yellow stator leads to the Yellow voltage regulator leads (electric start models). 21. Connect the remaining stator lead to the appropriate COl wiring hamess leadS. 22. Install the flywheel key into the crankshaft slot with the outer edge of the key parallel to the center-line of the crankshaft. Parallel.. OSI95G16 OSI95G17 Step 22 01195614 Step 2 IGNITION AND ELECTRICAL SYSTEMS 5-23 23. Align the slot in the in the flywheel center bore with the flywheel key and install the flywheel onto lhe crankshaft. 24. Install the washer and nut. 25. While holding the flywheel with a flywheel holder , torque the flywheel nut to 125 11. lbs. (169.5 Nm) 26. -·Replace lhe flywheel cover. 75-125 HP t See accompanying illustrations 1. Remove the flywheel cover from the engine. ** WARNING The engine could possibly start when you are turning the flywheel during removal and installation. Make sure to remove the spark plug leads from the spark plugs to prevent the engine from starIng. 2. While holding the flywheel with the flywheel holder ( 91--52344). remove the flywheel nut and washer. 3. Install the crankshaft protector cap ( 91-24161), then install a flywheel puller on the flywheel. 4. Hold the flywheel tooth with the wrench while tightening the bold down on the protector cap. Tighten the bolt until the flywheel comes free. .-Neither heat nor the use of a hammer should be used to aid in the removal of the flywheel. Damage to the electrical components underneath the flywheel may occur. 5. Remove the flywheel and flywheel key. 6. carefully inspect the flywheel for cracks or defects. 7. Inspect the crankshaft and llywheel tapers and key-ways for wear and damage. 8. Check for loose or damaged flywheel magnets (located in the outer rim and center hub). If necessary, replace the llywheel. 9. Remove the stator screw. 05195G18 Step 2 a •Sta-Strap b -Switch Box Bullet Connectors {Disconnect) 0519'.>G20 Step 12 10. Remove the starter motor. 11. Remove the wire ties on the wiring harness . 12. Disconnect the stator leads from the switch box on the 3-Cylinder models and remove the stator from the engine. 13. Disconnect the stator leads from the switch box on the 4-Cylinder models and remove the stator from the engine. 14. Disconnect the link arm. 15. Disconnect the trigger coil leads from the switch box. 16. Remove the trigger coil assembly. To install: 17. Install the trigger coif and link arm. 18. Connect the trigger leads to the switch box. 19. Install the sta-strap. .-There are two types of stators used on the 1994thru 1996 75 to 125hp engines. These stators can be identified by a large rim or small rim on the under side of the stator where the stator harness exits the stator. These stators must be installed as shown respectively or premature stator failure may occur as a result of stator interference with the engine block. a •Flywheel Pullerb · Flywheel ,. •.. 4 Cylinder Models a -Sta-Strap b -Stator Harness c -Sw•tGi 1 Box 05195621 05195G19 Step 4 Step 13 5-24 IGNITION AND ELECTRICAL SYSTEMS '{ Small Rim Stator a c Front of Engine a-Small Rim b · Exhaust Cover Bolt c •High/Low Speed Winding Module of Stator d •Stator Screws [Apply Loctite 222 to threads] (Torque screws to 60lb. ln. (6.8 N-m))e -Stator Hamess OS19SGZ2 Step 20 20. Install the small rim stator assembly aligned as illustrated to prevent premature stator wear. 21. Install the large rim stator assembly aligned as illustrated toprevent premalure stator wear.22. After installing the correct stator, apply a thread-locking compound and tighten the screws to 60 inch lbs. (6.8 Nm) 23. Connect lhe stator leads. 24. Install the flywheel key into the crankshaft slot with the outer edge of the key parallel to the center-line of the crankshaft. 25. Align the slot In the in the flywheel center bore with the flywheel key and install the flywheel onto the crankshalt. 26. Install the washer and nut 27. While holding the flywheel with a llywheel holder, torque the flywheel nut to 100 IL lbs. (136 Nm) 28. Replace the llywheel cover. Large Rim Stator tFront of Engine a •Large Rtm Stator b •Flywh.. Cover Stud c · High/low Speed Wi!1d•ng MOdule of Sea tor d •Stator Screws {Apply Locnte m to lhreadsJ ITorcue screws 10 60 !b. n (6.8 N·m)J e •Stator Harness IIS1ii!G23 Step 21 135-225 HP • See accompanying illustrations 1. Remove the llywheel cover lrom the engine. :;::;: WARNING The engine could possibly start when you are turning the flywheel during removal and Installation. Make sure to remove the spark plug leads from the spark plugs to prevent the engine from staring. 2. While holding the flywheel with a llywheel holder •remove the r!ywheel nut and washer. 3. Install the crankshall protedor cap (91-24161}, then install a tlywheel puller on the flywheel. 4. Hold the llywheel toolh with the wrench while tightening the bold down on the protector cap. Tighten the bolt until the llywheel comes tree. ..Neither heat nor the use ot a hammer should be used to aid In the removal ol the flywheel. Damage to the electrical components under· neath the flywheel may occur. 5. Remove the llywheet and llywheel key. 6. Carelully inspect the llywheel lor cracks or detects. 7. Inspectthe crankshaftand flywheel tapers and key-wayslor wear and damage. :r ,•.. IGNITION AND ELECTRICAL SYSTEMS 5-25 OS195G27 a ·Trigger b •Un.k Rod Swivel Step 12 Step 15 8. Check for loose or damaged flywheel magnets (located in the outer rim and center hub). II necessary, rsPiace the flywheel. 9. Remove the stator·screws. 10. Remove the wire ties on the wiring harness. 11. Remove the screws, which secures the stator assembly to the upper end cap. Lift oil the end cap and move it to the side. 12. Disconnect all the stator leads from the terminals and remove the stator assembly. 13. Remove the lock nut that secures the link rod swivel into the spark advance lever. Pull the link rod out of the lever. 14. Remove the t\'IO screws and lift the outer switchbox from the inner switchbox. Make sure not to loose the spacers. 15 Disconnect all the trigger leads from the terminals. Cut the sta-strap and remove the trigger plate assembly from the engine. 16. If the trigger assembly is faulty, remove and retain the link rod swivel from the trigger assembly. To install: 17. Install the trigger coil and link arm. Make sure lo keep a distance of 1Ylain. (17.5mm) between the pivot and the locknut on the ball joint 18. Place the trigger plate assembly in the upper end cap. Fasten the link rod swivel to the spark advance lever with the locknut. 19. Carefully route the wiring harness and reconnect the wires to their proper terminals. Wires with a Yellow identification sleeve must be connected to the outer switch box. 20. Clean the stator attaching screws and apply a thread-locking compound. Install the stator in position on the upper end cap and torque the screws to 50 inch lbs. (5.5 Nm). 21. Reconnect the stator leads to the vollage regulator/rectifier and switch boxes. Leads with the Yellow sleeve must be connected to the outer switchbox 22. Install the switchboxes to the engine with the screws and spacers. Make sure that both boxes are grounded to the engine thru the screws and spacers. ** CAUTION Switchboxes must be grounded to the engine before cranking the engine or the switch boxes will be terminally damaged. Step 19 a -Spali< Advance t.ever b ·Locknut c ·Trigger Hamcss C)i19..6 0519..4 3-.1ainthisl111t6ir\.(17.6mM)JOimei"Gion b ·Pivot c ·Lil'lkRod d ·Hex.. t! ·8a1Jo!nt Step 17 23. Install the flywheel key into the crankshaft slot with the outer edge ol the key parallel to the center-line ol the crankshaft. 24. Align the slot in the In the flywheel center bore with the flywheel key and install the flywheel onto the crankshaft 25. Install the washer and nut. 26. While holding the llywheel with a llywheel holder , torque the llywheel nut to 120ft. lbs. (163 Nm) 27. Replace the llywheel cover. Ignition Coil TESTING Spark Test • See Figure 42 A preliminary check of ignition coil function may be made by using a spark tester. Simply connect the spark tester between the ignition high tension lead and a good engine ground. Crank the powerhead and observe the spark tester. Spark should occur inside the glass enclosure. II i! does not. the ignition coil, or another ignition system component. may be faulty. Resistance Test ,.A mullimeter test can only detect certain faults in the ignition coil. Replace the ignition coil if the multimeter reading is not as specified. II the coil tests satisfactory and the coil is still suspected of being faulty, If the resistance is not within specification, the coil may be defective. 1. Retest the coil using a dedicated ignition coil tester or replace the coil with a known good unit to verify if the coil is bad. The primary and secondary coil resistance tests may be performed with the components installed on the powerhead. II chaffing or broken wiring is suspected, Fig. 42 Using a spark checker to check the ignition system spark ,'· 5-26 IGNITION AND ELECTRICAL SYSTEMS removalof the component is recommended to permit a complete inspection of all wiring leads. PRIMARY • See Figure 43 1. Disconnect the primary coil electrical lead. 2. Connect a multimeter to the coil primary lead and the other end to a good coi I ground. 3. Resistance should be approximately 0.02-G.04 ohms at 68°F (2o•c).4. If the resistance is not within specification, the coil may be defective. 5. Retest the coil using a dedicated ignition coif tester or replace the coil with a known good unit to verify if the coil is bad. {! 00195G32 Fig. 43 Connect the positive (+) meter lead to the coif and the negative (-) meter lead to the coil ground to test primary resistance. Connect the (+) meter lead to the spark plug lead terminal and the negative (-) to the coil ground to test secondary resistance SECONDARY • See Figure 43 1. Disconnect the secondary coil (high tension spark plug) lead. 2. Connect a mullimeter to the coil secondary tower and the other end to a good coil ground. 3. Resistance should be approximately BOQ-1000 ohmsat68°F (2Q•C). 4. If the resistance is not within specification. the coil may be defective. 5. Retest the coil using a dedicated ignition coil tester or replace the coil with a known good unit to verify if the coil is bad. Voltage Output Tests One of the most accurate ways of determining coil condition is to do a dynamic coil output voltage test. This test will show the actual coil output under varying conditionsand will not only determine if the coil defective, but will also alert the user to when coif is about to fail. Coil Voltage Output Testers are available from CDI Electronics (256-772-3829). 1. Remove the cowling. 2. Disconnect the spark plug high tension lead and connect thevollage oulput tester between the spark plug and the high tension lead. 3. Start (crank) the outboard and read the voltage front the tester. 4. Voltage shouldbe 18-20 Kv. 5. II vollage is not as specified, the coil may be defective. 6. Disconnect the tester and connect the spark plug high tension lead. 7. Install the cowling. REMOVAL & INSTALLATION 2.5-5 HP 1. Remove the engine cover. 2. Disconnect the CDI unit lead from the coil. 3. Disconnect the spark plug wire from the spark plug. 4. Disconnect the ground wires. 5. Remove the bolls and washers securing the ignition coil to the engine block and remove the ignition coil. To install: 6. Secure the coil to the engine block with the bolts and washers.Make sure to reconnect the ground wires. 7. Reconnect the CDI unit lead tothe ignition coil. 8. Connect the spark plug wire to the spark plug. 6-25 HP • See Figure 44 1. Remove the engine cover. 2. Disconnect the spark plug wires from the spark plugs. 3. Disconnect the coiltower boots and remove the spark plug wire from the ignition coil. 4. Disconnect the positive and negative lead wires at the ignition coil. Mark these wires tor proper installation during reassembly. 5. Unbolt and remove the coil assemblyfrom the engine block.Make sure to keep track of any spacers (and ground plates if equipped) needed for assembly. To install: 6. Installthe coil assembly onto the engine block. Make sure that all spacers or ground plates are in place. 7. Install the coil tower boots and spark plug wire. Make sureto make awateriight seal between the coil towers and the spark plug leads by using Quicksilver Insulating Compound or equivalent. 8. Aitach the positive and negative lead wires onto lhe correct terminals. Tighten the nutsto 35 inch lbs. (4 Nm), then coat the terminalsand nuts with Quicksilver Liquid Neoprene or equivalent. 30 and 40 HP (2-Cylinder) • See Figure 45 1. Disconnect lhe negative battery cable. 2. Remove the engine cover, 3. Disconnect the high-tension spark plug lead at the spark plug. 4. Unplug the wiring harness and unscrew the ground wire (if equipped). 5. Remove the retaining screws and remove the coil from the electrical plate. To install: 6. Installthe coil onto the electrical plate with the retaining screws. 7. Reconnect the wiring harness and lighten ground wire (if equipped). 8. Connect the high-tension spark plug lead to the spark plug. 9. Replace the engine cover. 10. Connect the battery negative cable. 40-60 HP (3-Cylinder) • See Figure 46 .-Always disconnect the batt.ery and spark plug high-tension lead before working on the ignition system. 05195630 Ffg. 44 Coil assembly-& to 25hp :r IGNITION AND ELECTRICAL SYSTEMS 5-27 a -Wire Harness Plug b · Screws a ·Posltive(•ll.t:.aOb ·Ncgalive (-} Lead e·High Tension Lead d ·CciiTOW918oot e-c..05195G3l Fig. 45 Coil assembly-30 and 40hp (2· Cylinder) Fig. 46 Coil assembly-41Hi0 HP (3-Cylinder) Fig. 47 Coil assembly-40 HP (4-Cylinder) t Remove the engine cover. 2. Disconnect the wiring harness connector. 3. Remove the screwilhat secure the coiIassembly to the ignition plate and remove the coil assembly. To install: 4. Position the coil on the ignition plate and install the retaining screws. Torque the screws to 60 inch lbs. (6.8 Nm).5. Connect the wiring harness. 6. Install the engine cover. 40 HP (4-Cylinder) • See Figure 47 1. Remove the engine cover. 2. Remove the bolts securing the electrical box access cover and removethe cover. 3. Disconnect the wires from the positive (+) and negative (-) terminals on the tautly ignition coil. 4. Removethespark plug boot oilthe spark plug. 5. Remove the spark plug high-tension lead/coil tower ooot assemoly from the ignition coil tower. 6. Remove and discard the faulty ignition coil. To install: 7. Installthe spark plug high-tension lead/coil tower boot assembly onto the new ignition coi I. 8. Position the ignition coil into the electrical box. 9. Reconnect the positive (+) and negative (·) meter leads to the terminals with two nuts. Torque the nuts to 30 inch lbs. (3.4 Nm). 10. Reconnect the spark plug boot to the spark plug. 11. Reinstall the electrical access cover and tighten the securing bolts. 12. Install the engine cover. 76-115 HP 1. Remove the engine cover. 2. Disconnect the battery cables. 3. Remove the spark plug high-tension lead from the spark plug. 4. Remove the primary wires from the coil terminals. Mark the wires for proper placement during assembly. 5. Remove the retaining bolls and remove the laulty coil from the engine. To install: 6. Align the coil on the engine and install the retaining bolts. Tighten to 20 inch lbs. (2.3 Nm).7. Install the primary wires and nuts onto thecorrect terminal. Tighten the nuts to 30 inch lbs. (3.4 Nm) and coat the terminals and nuts with Quicksilver Liquid Neoprene. 8. Install the spark plug high-tension wire on to the coil tower. Make sure that there is a watertight seat between the wire and coil tower by using Quicksilver Insulating Compound or equivalent. 9. Reconnect the oaHery cables. 10. Replace the engine cover. 135-225 HP 1. Remove the bolts securing !he ignition coil/relay cover and remove the cover. 2. Remove the spark plug high-tension leads from the faulty coil. 3. Disconnect the primarywires from thecoil terminals. 4. Remove the screws and nuts and lift the coil cover along with the coils from the engine Remove the defective coil from the cover. To install: 5. Install the coil into the coil cover and install it back on the engine with the retaining screws and nuts. 6. Reconnect the switch box wire to the positive (+) coilterminal and the Black ground wire to the negative(·) coil terminal. 7. Pull the boot backand insert the spark plug lead into the coil. Make sure that there is a watertight seal between the wire and coil tower by using Quicksilver lnsu· lating Compound or equivalent. OpliMax • See Figures 48 and 49 1. Disconnect the coil harness andsparkplug leads. 2. Loosen the electrical mounting plate to access the rear locknuts. 3. Remove the module attaching boils and remove the ignition module. To install: 4. Attach the module to the electrical mounting plate. 5. Reconnect the spark plug lead and coil wiring harness. Capacitor Discharge Module (Switch Box) TESTING Diode Test (2.5·3.3 HP Only) • See Figures 50 and 51 1. Connect a multimeter between the White and Orange module leads. 2. Continuity should exist with the leads connected in one direction and should not exist with the leads reversed .. 3. If the diode does nol lunctionas specified, the module may befaulty. b. Spacer-place on bolls between cois c. lgniOOn coils d.Sporl< Jll"'l'"ad e. Electrical mounlng !)tate I. Blacket Fig. 48 1gnition coil components and location-115 to 150hp .... 5-28 IGNITION AND ELECTRICAL SYSTEMS a ·Electrical Mounting Plate b ·Screw c ·Washer d · Rullbe< Grommet e ·Boltst ·l..tion Coils g -Screw h •Spar!< Plug Leadi · Plug Boot j Fig. 49 Ignition coil components and location-200 to 225hp Direct Voltage Output 1. Remove all the spark plugs. 2. Install a spark plug gap tool to each spark plug boot and attach thealligator clips to a good engine ground. 3. Disconnectthe powerhead from its fuel supply 4. locate the CD module (switch box). 5. There are two ways to connecta mullimeter with peak reading adapter to the module harness. The first isto use afactory style wiring harness adapter. These adapters can be obtained from your Mercury dealer. The second way isto usepiercing probes available fromaftermarket tool manufacturers. 6. Connect themultimeteratthewires connected to the ignition coil Positive (+) and Negative (-) terminals. 7. Use thestarter motor or recoil starter to crank the engine. .-u it is not possible to obtain a cranking speed high enough to properly test the switch box, the engine can be tested in the same manner while running. 8. Voltage should be at feast 100V +. 9. If vollage is within specification and there isa no spark orweak spark condition, the ignition coif may be faulty. 10. If voltage is below specification. testthe ignition coil. 11. If the ignition coil is functioning properly, replace the CO module (switch box) and retest. 12. Disconnect the multimeter with peak reading adapter. Stop Circuit 1. Remove all the spark plugs. 2. Install a spark plug gap tool to each spark plug boot and attach the alligator clips to a good engineground. 3. Disconnect the powerhead from its fuel supply. 4. locate the wire leading from the co module (switch box) to the stop switch. 5. There are two ways to connect a rnultimeterwith peak reading adapter to the module harness. The first is to use a factory style wiring harness adapter. These adapters can be obtained from your Mercury dealer. The second way is to use piercing probes available from aftermarket tool manufacturers. 6. Connect the multimeter between the White charge/lrigger coil wire and ground. 7. Use the starter motor or recoil starter to crank lhe engine. Note the cranking voltage. 8. If cranking voltage is below 120 volts,disconnect the White wire and retest. If voltage increases above 200 volts,the CO module (switch box) is faulty and should be replaced. 9. If cranking voltage is above 320volts, and there Isno change in voltage when you disconnect the White wire, CD module (switch box) is faulty and should be replaced. 10. Disconnect the multimeter with peak reading adapter. Switch Box Bias .-switch box bias tests must be performed using a conventional multimeter. If the outboard is equipped with an idle speed stabilizer or spark advance, disconnect these prior to testing. 1. Remove all the spark plugs. 2. Install a spark plug gap tool to each spark plug boot and attach the alligator clips to a good engine ground. 3. Disconnect the powerhead from its fuel supply. 4. locate the bias wire (usually Black/While). 5. Connect the mullimeter between the bias wire and ground. 6. Use the starter motor orrecoil starter to crank the engine. Note lhe crankingvoltage. 7. Switch box biasvoltage should be between 2-106volts DC at cranking speed. 8. If cranking voltage is below specification, one or both of the switch boxes may be faulty. 9. Ifswitch box voltage is within specification and the outboard still runs poorly, check the trigger/charge coil. If the trigger/charge coil is functioning properly, replace the switch boxes and retest. .-Frequently, switch box bias failure can be attributed to poor grounding between the switch boxes. 10. Disconnect the multimeter. REMOVAL & INSTALLATION 2...3.3 HP • See Figure 52 1. Remove the top cowling.2. Remove the PORT side lower cowling. a· WHITE Lead •-891t f ..Capacitot DischargeModute 061951'09 06195P12 Fig. 51 . . . and zero continuity-COM (Diode Test) 2.5 and 3.3hp OSI95G38 Fig. 52 CD module location-2.5 to 3.3hp IGNITION AND ELECTRICAL SYSTEMS 5-29 ' ,_ 05195G39 Fig. 53 CD module locatio.. to 25hp ..195Gl1 Fig. 54 CD module-3D and 40hp (2-Cylinder) 3. Disconnect the bullet connectors at the CD module (switch box). It is a good idea to label the wiring connectors before disassembly. This will aid in assembly. Also make sure to disconnect the ground lead from the secondary ignition coil retaining bolt. 4. Remove the bolt securing the CD module (switch box) to the engine block. To install: 5. Secure the CD module (switch box) to the engine block with the retaining boll. 6. Fasten the ground lead to the block with the secondary ignition coil retaining boiL 7. Reconnect the bullet connectors in the correct order. 8. Reinstall the PORT side lower engine cowling. 9. Reinstall the top cowling. 4 and 5 HP 1. Remove the top cowling. 2. Disconnect the bullet connectors at the CD module (switch box). II is a good idea to label the wiring connectors before disassembly. This will aid in assembly. 3. Disconnect the ground lead from the secondary ignition coil retaining bolt. 4. Slide the CDmodule (switch box) out of the rubber brackets and remove it. To install: 5. Slidethe CDmodule (switch box) back into the rubber brackets. 6. Reconnect the bullet connectors in the correct order. 7. Fasten the ground lead to the block with the secondary Ignition coil retaining boll. 8. Reinstall the top cowling. 6-25 HP • See Figure 53 1. Removethetop cowling. 2. Disconnect the bullet connectors atlhe CDmodule (switch box). II is a good idea to label the wiring connectors before disassembly. This will aid in assembly. 3. Disconnect the ground lead wire. 4. Removethe retaining screws and lift off the CD module (switch box) and remove it from the engine. To install: 5. Align the CDmodule (switch box) onto the engine block and install the retaining screws, tightening them firmly. 6. Reconnect the bullet connectors in the correct order. 7. Fastenthe ground lead wire. 8. Reinstall the top cowling. 30 and 40 HP (2-Cyllnder) • See Figure 54 1. Disconnect the negative battery cable. 2. Remove the engine cover. 3. Disconnect the high-tension spark plug lead at the spark plug. 4. Unplug the CD module (switch box) wiring harness and unscrew the ground wire (if equipped). 5. Removethe retaining screws and remove the CDmodule (switch box) from the electrical plate. To install: 6. Install the CD module (switch box) onto the electrical plate with the retaining screws. 7. Reconnect the CD module (switch box) wiring harness and tighten ground wire {if equipped). 8. Connectthe high-tension spark plug lead lo the spark plug. 9. Replace the engine cover. 10. Connect the battery negative cable. 3G-125 HP 1. Remove the top cowl. 2. Remove the retaining bolls from the electrical box access cover and remove the cover. 3. Disconnect the leads from the switchbox. ,..Mark each lead as to its proper location. This greatly aids in reassembly later. 4. Remove the bolls from the switchbox and remove the switchbox. To install: 5. Secure the switchbox to the electrical component box with the retaining bolts and ground leads. 6. Torqure the bolts to 40 inch lbs. (45 Nm). 7. Reconnect the leads to the switchbox terminals. Make sure all the leads are installed in their proper places. 8. Torque the nuts to 30 inch lbs. (3.4 Nm). 9. Reinstall the electrical box access cover and secure it with the retaining bolts. 10. Install thetop cowl. 135 to 275 HP • See Figure 55 The switchboxes are grounded to the engine through the mounting screws, spacers and ground wires {if so equipped). 1. Make sure the ignition switch is off and disconnect the battery cables. 2. Remove the screws and lift the switchboxes offthe engine, Make sure notlo loose the metal spacers. 3. Remove the rubber cover on each wire terminal and remove the terminal nuts. Disconnectthe wire leads and remove lhe switchboxes. ,..Mark each lead as to Its proper location. This greatly aids in reassembly later. To install: 4. Reconnect the leads to the correct terminals in the switchbox. The wires with the Yellow idenlilicalion sleeves must be connected to the outer switch box. Connect a ground lead (if equipped) to each switchbox. 5. Apply a thread-locking compound to the switchbox mounting screws. Install the swilchboxes onto the powerhead using the screws and spacers. ,..Be certain the switchboxes are properly grounded to the powerhead or damage to the switchboxes will occur when cranking or running the engine. ..191G-l3 Fig. 55 CD module retaining screw and spacer locations 5-30 IGNITION AND ELECTRICAL SYSTEMS CHARGING CIRCUIT Description and Operation The battery stores electricity and acts as a sponge for the whole system. It mops up -generated current until it's fully charged and it releases energy on demand. The flywheel ,holds the permanent magnets that create the moving magnetic field. If your engine has good spark. you can take it tor granted that the magnets are in working order because the ignition and charging systems share the same magnets. The stator windings are the stationary coils of wire the flywheel magnets rotate around. They produce the electrical charge. Simply put, the more windings in your stator, the greater the potential output in amps your charging system will have. The reciifier consists ofa series ol diodes or one-way electrical valves. It rectifies or corrects lhe alternaling current (AC) produced within the windings lo charge the direct current (DC) battery. the disadvantages ol a current-generating system using permanent magnets and stator windings, which is that the current produced within the windings is alternating current (AC). You can't use AC to charge batteries. They accept only direct current (DC). So the rectifier is designed to convert AC current to a usable form of DC current simply called rectified AC. On midsize and large outboard engines, there may be a voltage regulator, either combined with the rectilier or standing alone. The regulator automatically reduces the output ol generated current as the battery becomes tully charged. The voltage regulator controls the alternators field voltageby grounding one end ot the field windings very rapidly. The frequency varies according lo current demand the more the field is grounded, the more voltage and current the alternator produces. Voltage is maintained at about 13.5-15 volts. During high engine speeds and low current demands, the regulator will adjust the voltage of the alternator field to lower the alternator output voltage. Conversely, when the engine is idling and the current demands may be high, the regulator will increase field voltage, Increasing the output of the alternator. The rectifier is primarily used for charging the battery circuit on electric start models with the 9-amp stator alternator. The unit is a solid state seated unit containing a series of diodes. This means that the unit is non-repairable and must be replaced if found to be defective. Troubleshooting the Charging System The charging system should be inspected il: • The charging system warning light is illuminated • The voltmeter on the instrument panel indicates improper charging (either high or low)voltage • The battery is overcharged (electrolyte level is low and/or boiling out) • The battery isundercharged (insufficient power to crank the starter) The starting point for all charging system problems begins with the inspection ol the battery, related wiring and charging system components. The battery must be in good condition and fully charged before system testing. Do a visual check of the battery, wiring and fuses. Are there any new additions to the wiring? An excellent clue might be, everything was working ok until ! added that live well pump. With a comment like this you would know where to check first. ,.Check battery condition thoroughly. II is the #1 culprit in charging system failures. The regulator/rectifier assembly is the brains of the charging system. The regulator controls current flow in the charging system. II battery voltage is below about 14.6 volts the regulator sends the available current to the battery. If the battery is fully charged (about 14.5 to 15 volts) the regulator diverts the current/amps to ground. Do not expect the regulator to send current to a fully charged battery. Check the battery fora possible draw with the key off. This draw may be the cumulative effect of several radio and/or clock memories. II these accessories are wired to the battery then a complaint of charging system failure may really be excessive draw. Draw in excess ol 25 milliamps should arouse your suspicions. ,.Do not forget to check through the !uses. It can be embarrassing to overlook a blown fuse. Youmust pull the battery voltage down below 12.5 voltsto test charging system output. Running the power trim and tilt will reduce the battery voltage. Once the battery's good condition is verified and it has been reduced to below 12.5 volts you can test further. Install an ammeter to check actual amperage output. Verify that the system is delivering sufficient amperage. Too much amperage and a battery that goes dry very quickly indicates that the rectifier/regulator should be replaced. II the system does not put out enough amperage, then lest the lighting coi I. Isolate the coil and test for correct resistance and short to ground. During these test procedures the regulator/rectifier has not been bench checked. Usually it is advisable to avoid troubleshooting the regulator/rectifier directly. The procedures listed so far have focused on checking around the rectifier/regulator. II you verify that all other systems stator are good then what is lett in the system to cause lhe verified problem? The process of elimination has declared the rectifier/regulator bad. Stator (Alternator) TESTING Except OptiMax • See Figures 56 and 57 1. The stator may be tested without removing the flywheel. by merely disconnecting the Yellow leads and using a muttimeter to check the resistance. 2. Check resistance between the two Yellow stator wires. 3. Resistance should be as specified in the "Stator Alternator Resistance Specification' chart. 4. If the slator is installed on the powerhead, check continuity between each Yellow stator wire and ground. 5. II the stator is not installed on the powerhead, check continuity between each Yellow stator wire and the Black ground wire. 03517P02 Fig. 56 Once the flywheel is removed, major ignition components are exposed for service Stator Alternator Resistance SAmp MMua! Start 14Ail'9 18An'l,) 9-16Amp9.0.mp 16·18Amp 16 Amp ReQula!OGf14 Fig. 59 Insert the bent end of the tool through the end cover and ground Terminal F 2. Start the engine and allow it to reach operating temperature. 3. Advance the engine rpm to 2000 rpm. 4. Insert the fabricated special tool through the end cover and ground Terminal F. 5. Normal output is 52-60 amps @2000 rpm at the alternator. 6. If alternator output is normal, replace the regulator. 7. lithe output is low, a disassembly of the alternator is necessary to inspect and test individual alternator components. REMOVAL & INSTALLATION ,. The stator is located under the flywheel. To gain access to the stator the flywheel must be removed. 6-25 HP • See Figure 60 1. Disconnect the battery leads from the battery terminals. Remove the lront cowling cover and the wrap-around cowling, il one is used. Remove the top cowling, Remove the nut on the crankshaft in the center of the flywheel. A flywheel holder will be required to prevent the flywheel lrom rotating while the nut is loosened. 2. Obtain the proper flywheel puller to "pull" the flywheel. Never use a puller which pulls on the outside edge of the flywheel or the flywheel may be damaged. Alter the puller is installed, tighten the center screw onto the end of the crankshaft Continue tightening the screw until the nywheel is released from the crankshaft Remove the IIY'A'fleet puller. Uft the flywheel free of the crankshaft. The Woodruff key in the flywheel may remain In place but take care the crankshaft is not jarred and the key falls free and is lost. 3. Disconnect the Yellow and Gray wires le..ding from the allernator to the terminal block on the rectifier. Reroove the retaining bolls from the alternator and lilt the alternator from the powerhead. To Install: 4. Place the allernator in position on the powerhead. Coat the threads ol the alternator attaching bolts with blue Loctite" or equivalent. Secure the alternator with the attaching bolts through the alternator into the powerhead. 5. Insert the Woodruff key into the flywheel recess with just a bit of grease to hold it in place. Check to be sure the inside taper of the flywheel and the taper on the crankshaft are clean of dirt or oil, to prevent the flywheel from attempting to "walk" on the crankshaft during operation. Slide the flywheel down over the crankshaft with the keyway in the fiYivheel aligned with the Woodruff key in the crankshaft. Rotate the fl}'lvheel clockwise and check to be sure the flywheel does not contact any powerhead part or any ot the wiring. Thread the flywheel nul onto the end of the crankshaft and then tighten it to specification. 5-32 IGNITION AND ELECTRICAL SYSTEMS Flg. 60 The alternator can be removed without disturbing the trigger coil 30 to 125 HP • See accompanying illustrations 1. Disconnect the ball.ery leads from the battery terminals. Unlatch and swing open or lilt oft the powerhead cowling, lift up and remove the cowling halves I rom the powerhead. 2.. Remove the spark plug from all cytinoorsto prevenl the po1.read from starting. 3. Refl'lO\Ie the three bolts securiJY;J the flywheel cover or hand rewind starterif so equipped. Remove the nut on the cranks hall in the cenler o! the flywheel. A lly· wheel holding tool (91-52344) will be required to prevent the flywheel trom turning in order to loosen the nul 4. Install crankshall protector cap (9124161) over the end ol the crankshalt. Thread flywheel puller (91-73687AI) as far into the llywheel as possible. Never use a puller which pulls on the outside edge ol lhe flywheel or the flywheel may be dam­aged. Hold the outer portion of the flywheel puller tool stationary and turn the centerboltuntil the flywheel is free of the crankshafl lifl lhe flywheel lrom tile crankshaft. lilt the ftywheel lrom the crankshaft and remove the cranll lead to either aL W lead. COnn N ATIVE (·) test lead to thick RED lead. Connaco NE TIV (·) 1..1 lead 10 ehherYELL W leod. Connect NECA TIVE(·) l&st lead to <8$8 OtoSSible faulty components. 5-38 IGNITION AND ELECTRICAL SYSTEMS Obtain a mullimeter and set the meter switches for "Continuity Testing·. Perform the steps as listed in the "Rectifier Troubleshooting Test". REMOVAL & INSTALLATION • See Figures 68 and 69 In most cases the rectifier is easily removed, because it is housed under the electrical access cover on the starboard side of the powerhead. Before removing the rectifier, be sure to disconnect the battery leads at the battery first. Remove the Yellow stator leads, red positive lead and Gray tachometer lead if equipped. Remove the two mounting screws securing the rectifier to. the powerhead and lift off the rectifier. ** CAUTION Never attempt to check the polarity of the battery leads by sparking the terminals against the battery posts. Such action will burn out the rectifier. A burned-out rectifier in most cases is caused by improper procedures at the battery or when handling the battery leads as outlined in the following short list. 1. The baitery fea.s of the electrical control harness are connected to Lhe wrong terminals at the battery. 2. The battery leads were disconnected from the battery terminals while the powerhead was running. 3. An open circuit resulting from a broken wire, loose connection. corroded switch contact or a loose harness connector at the powerhead. To install: 4. Place the rectifier in position on the powerhead and secure it with two screws. Tighten the screws to 30 inch lbs. (3.3Nm). 5. Connect the two Yellow leads from the stator to the alternator terminals on the rectifier. If the powerhead is equipped with a tachometer-connect the Gray wire from the tachometer to one of the Yellow wire terminals on the rectilier. 6. Connect the positive lead from the starter solenoid to the positive (+) terminal on the rectifier. Aller all connections are completed, coat all terminals with Mercury liquid neoprene (92-25711) or equivalent, to prevent corrosion on the terminals. Battery The ballery is one of the most important parts of the electrical system. In addition to providing electrical power to start the engine, it also provides power lor operation of the running lights, radio and electrical accessories. Because of itsjob and the consequences {failure to perform in an emergency), the best advice is to purchase a well-known brand, with an extended warranty period, from a reputable dealer. The usual warranty covers a pro-rated replacement policy, which means the purchaser is entitled to consideration for the time left on the warranty period if the battery should prove defective before the end of the warranty. Many manufacturers have specifications on the size and type of battery to use for their engines. If in doubt as to how large the boat requires. make a liberal estimate and then purchase the one with the next higher amp rating. Outboards equipped with an onboard computer, should be equipped with a battery of at least 100 to 105 amp/hour capacity. · Negative brush OOS57P11 BATTERY CONSTRUCTION • See Figure 70 A battery consists of a number of positive and negative plates immersed in a solution of diluted sulfuric acid. The plates contain dissimilar active materials and are kept apart by separators. The plates are grouped into elements. Plate straps on lop of each element connect all of the positive plates and an of the negative plates into groups. The battery is divided into celfs holding a number of the elements apart from the others. The entire arrangement is contained within a hard plastic case. The top is a one-piece cover and contains the filler eaps for each cell. The terminal posts protrude through the top where the battery connections for the boat are made. Each of the celfs is connected to its neighbor in a positive-to-negative manner with a heavy strap called the cell connector. MARINE BATTERIES • See Figure 71 Because marine batteries are required to perform under much more rigorous conditions than automotive batteries, they are constructed differently than those used in automobiles or trucks. Therefore. a marine battery should always be the No. 1 unit for the boat and other types of batteries used only in an emergency. Marine batteries have a much heavier exterior case to withstand the violent pounding and shocks imposed on it as the boat moves through rough water and in extremely tight turns. The plates are thicker and each plate is securely anchored within the battery case to ensure extended life. The caps are spill proof to prevent acid from spilling into the bilge when the boat heels to one side in a tight turn or is moving through rough water. Because of these features, the marine battery will recoverfrom a low charge condition and give satisfactory service over a much longer period of time than any type intended for automotive use. ** WARNING Never use a Maintenance-free battery with an outboard engine that is not voltage regulated. The charging system will continue to charge as long as the engine is running and it is possible that the electrolyte could boil out if periodic checks of the cell electrolyte level are not done. BATTERY RATINGS • See Figure 72 Three different methods are used to measure and indicate battery electrical capacity:• Amp/hour rating • Cold cranking performance • Reserve capacity The amp/hour rating of a battery refers to the battery's ability !o provide a set amount of amps for a given amount of time under test conditions at a constant temperature. Therefore, if ihe battery is capable of supplying 4 amps of current for 20 consecutive hours, the battery is rated as an 80amp/hour battery. The amp/hour rating is useful for some service operations. such as slow charging or battery testing. Fig. 68 View of a typical voltage rectifier with terminal identification, as mentioned in the text Fig. 69 Removing the cover exposing much of the powerhead electrical connections and showing typical location of the rectifier Fig. 70 Typical 12 volt battery cell arrangement IGNITION AND ELECTRICAL SYSTEMS 5-39 Fig.71 Cut-away look at a typical marine battery % ----o· • Fig.72 Comparison of battery efficiency and engine demands at var0>! 951'28 Fig.73 A good example of a secured, well protected and ventilated battery area BATTERY CHARGERS • See Figure 74 POWER (WATTS) AVAILABLE POWER (WATTS) REQUIRED 100% .. 165% .. 83e ENERGIZERS RATED AT61% o•Fe ···· - 45% 8 ious temperatures Cold cranking performance is measured by cooling a fully charged battery to o•F ( -17.C) and then testing it for 30 seconds to determine the maximum current flow. In this manner the cold cranking amp rating is the number of amps available to be drawn from the battery before the voltage drops below 7.2 volts. The illustration depicts the amount of power in watts available from a battery at dilferent temperatures and the amount of power in watts required of the engine at the same temperature. It becomes quite obvious-the colder the climate, the more necessary for the battery to be tully charged. Reserve capacity of a battery is considered the length of lime, in minutes. at so•F (27•C), a 25amp current can be maintained before the voltage drops below 10.5 volts. This test is intended to provide an approximation of how long the engine, including electrical accessories, could operate satisfactorily if the stator assembly or lighting coif did not produce sulficienl current. A typical rating is 100 minutes. ,..If possible, the newbattery should have a power rating equal to or higher than the unit it is replacing. ,'-BATTERY LOCATION • See Figure 73 Every battery installed in a boat must be secured in a well protected, ventilated area. If the battery area lacks adequate ventilation. hydrogen gas. which is given off during charging, is very explosive. This is especially true if the gas is concentrated and confined. Before using any battery charger, consul! the manufacture r' s instructions lor its use. Battery chargers are electrical devices Ihat change Alternating Current (AC) to a lowervoltage of Direct Current (DC) that can be used to charge a marine battery. There are two types ot battery chargers-manual and automatic. A manual battery charger must be physically disconnected when the battery has come to a full charge. If not, lhe battery can be overcharged and possibly fail. Excess charging current at the end of the charging cycle will heat the electrolyte,resulting in loss of water and active material, substantially reducing battery fife. ,..As arule,onmanual chargers, when the ammeter onthe charger registers half the rated amperage of the charger, the battery is fully charged. This can vary and it is recommended to useahydrometer to accurately measure state of charge . Automatic battery chargers have an important advantage--they can be left connected (for instance, overnight) without the possibilily of overcharging the battery. Automatic chargers are equipped with a sensing device to allow the battery charge to taper off tonear zero as the battery becomes tully charged. When charging a low or completely discharged ballery, the meter will read close to full rated output. If only partially discharged, the initial reading may be fess than lull rated output,as the charger responds to the condition of the battery. As the battery continues to charge, Fig.74 Automaticchargers, such as the Battery Tende,. from Del Iran, are equipped with a sensing device to allow the battery charge totaper off to nearzeroas the battery becomes fully charged 5-40 IGNITION AND ELECTRICAL SYSTEMS the sensing device monitors the state of charge and reduces the charging rate. As the rate of charge tapers to zero amps. the charger will continue to supply a few milliamps of current-just enough to maintain a charged condition. BATTERY CABLES Battery cables don't go bad very often but like anything else, they can wear out II the cables on your boat are cracked, frayed or broken, they should be replaced. When working on any electrical component, it is always a good idea to disconnect the negative(-) battery cable. This will prevent potential damage to many sensitive electrical components Always replace the battery cables with one of the same length or you will increase STARTER CIRCUIT Description and Operation • See Figure 75 In the early days, all outboard engines were started by simply pulling on a rope wound around the lly..heel. As time passed and owners were reluctant to use muscle power, it was necessary to replace the rope starter with some form ol power cranking system.Today, many small engines are still started by pulling on a rope but others have a powered starler motor installed. The system utilized to replace the rope method was an electricstarter motor cou· pled with a mechanical gear mesh between the starter motor and the powerhead flywheel. similar to the method used to crank an automobile engine. As the name implies, the sole purpose of the starter motor circuit is to control operation of the starter motor to crank the powerhead until the engine is operating. The circuit includes a relay or magnetic switch to connect or disconnect the motor !rom the battery. The operator controls the switch with a key switch. A neutral safely switch is installed into the circuit to permit operation of the starter motor only II the shill control lever is in neutral. This switch is a safety device to prevent accidental engine start when the engine is in gear. The starter motor is a series wound electric motor which draws a heavy current from the battery. It Is designed lo be used only for short periods of time to crank the enginetor starting. To prevent overheating the motor. cranking should not be continued for more than 30-seconds without allowing the motor to cool lor at least three minutes. Actually, this time can be spent in making preliminary checks to determine why the engine fails to start. Power is transmitted from the starter motor to the powerhead flywheel through a Bendixdrive. This drive has a pinion gear mounted on screw threads. When the motor is operated, the pinion gear moves upward and meshes with the teeth on the llywheel ring gear. When the powerhead starts, the pinion gear is driven laster than the shan and as a result, it screws out of mesh with the flywheel. A rubber cushion is built into the Bendix drive to absorb the shock when the pinion meshes with the flywheel ring gear. The parts olthe drive must be properly assembled lor efficient operation. II the screw shall assembly Is reversed, It will strike the splines and the rubber cushion will not absorb the shock. The sound of the motor during cranking is a good indication of whether the startermotor is operating properly or not. Naturally, temperature conditions will 88528G5'l Fig. 75 A typical starting system converts electrical energy into mechanical energy to turn the engine. The components are: battery, to provide electricity to operate the starter, ignition switch, to control the energizing of the starter relay or relay, starter relay or relay, to make and break the circuit between the battery and starter, starter, to convert electrical energy into mechanical energy to rotate the engine, starter drive gear, to transmit the starter rotation to the engine flywheel resistance and possibly cause hard starling. Smear the battery posts with a light film of dielectric grease or a battery terminal protectant spray once you've installed the new cables. II you replace the cables one at a time, you won't mix them up. ,..Any time you disconnect the battery ca.bles, it is recommended that you disconnect the negative (-) battery cable first. This will prevent you from accidentally grounding the positive (+) terminal when disconnect· ing it, thereby preventing damage to the electrical system. Before you disconnect the cable(s), first turn the ignition to the OFF position. This will prevent a draw on the battery which could cause arcing. When the battery cable(s)are reconnected (negative cable last), be sure to check all electrical acces· sories are all working correctly. affect the speed at which the starter motor is able to crank the engine. The speed of cranking a cold engine will be much slower than when cranking a warm engine. An experienced operator will learn to recognize the favorable sounds of the power head crankingunder various conditions. The job of the starter motorrelay is to complete the cfrcuit between the baltery and starter motor. It does this by closing the starter circuit electromagnetically, when activated by lhe key switch. This is a completely sealed switch, which meets SAE standards lor marine applications. Do not substitute an automotive-type relay tor this application. It is not sealed and gasoline fumes can be ignited upon starting the powerhead. The relay consists of a coil winding, plunger, return spring, contact disc and lour externally mounted terminals. The relay is installed inseries withthepositive battery cables mounted to the two larger terminals. The smaller terminals connect to the neutral switch and ground. Toactivate the relay, the shift lever is placed in neutral. closing the neutral switch. Electricity coming through the ignition switch goes into the relay coil winding which createsa magnetic field. The electricity then goes on to ground in the powerhead. The magnetic lield surrounds the plunger In the relay, which draws the disc contact into the two larger terminals. Upon contact of the terminals, the heavy amperage circuitto the starter motor Is closed and activates the starter motor. When the key switch is released, the magnetic field is no longer supported and the magnetic field collapses. The return springworking on the plunger opens the disc contact, opening thecircuit to the starter. When the armature plate is out or position or the shill lever is moved into forwardor reverse gear, the neutral switch is placed in the open position and the starter control circuit cannot be activated. This prevents the powerhead Iromstarting while in gear. Troubleshooting the Starting System It the starter motor spins but !ails to crank the engine, the cause is usually a corroded or gummy Bendix drive. The drive should be removed, cleaned and given an inspection. 1. Before wasting too much lime troubleshooting the starter motor circuli,the following checks should be made. Many times, the problem will be corrected. • Battery fully charged. • Shirt control lever in neutral. • Main 20-amp fuse located at thebaseofthe fuse cover is good (not blown). • Allelectricalconnections clean and light. • Wiringin good condition, insulation not wornor frayed. 2. Starter motor cranks slowly or not at all. • Faulty wiring connection • Short-circuited lead wire • Shift control not engaging neutral (not activating neutral startswitch) • Detective neutral start switch • Starter motor notproperly grounded Faulty contact point inside ignition switch • Bad connections on negative battery cable to ground (atbattery side and engine side) • Bad connections on posilive battery cable to magnetic switch terminal • Opencircuit in the coil of the magnetic switch (relay) • Bad or run-down battery • Excessively worn down starter motor brushes • Burnt commutatorinstartermotor • Brush spring tension slack • Short circuit in starter motor armature 3. Starter motor keeps running. • Melted contact plate inside the magnetic switch • Poor ignilion switch return action 4. Starter motor picks up speed, put pinion will not mesh with ring gear. IGNITION AND ELECTRICAL SYSTEMS 5-41 • Worn down teeth on clutch pinion • Worn down teeth on flywheel ring gear 5. Two more areas may cause the powerhead to crank slowly even though the starter motor circuit is in excellent condition • A tight or frozen powerhead • Water in the lower unit. Starter Motor REMOVAL & INSTALLATION 8-25 HP • See Figure 76 1. Before beginning any work on the starter motor, disconnect the positive(+) lead from the battery terminal. 2. Remove the cowling from the powerhead. 3. Disconnect the Yellow cable at the starter motor terminal or at the solenoid. 4. Remove the mounting bolts from the starter motor housing and remove the motor from the powerhead To install: 5. Install the starter motor to the powerhead and secure it in place with the two mounting bolts. Tighten the bolts securely. Connect the lead to the solenoid. Connect the leads to the battery terminals. 6. Reconnect the Yellow cable at the starter motor terminal or at the solenoid. 7. Install the cowling onto the powerhead. 8. Connect the positive(+) battery lead. Fig. 76Starter motor and mounting bolt location :r r'· 30-275 HP 1. Before beginning any work on the starter motor, disconnect the positive (+) lead from the battery terminal. 2. Unlatch and remove the cowling from the powerhead. 3. Disconnect the cable from the solenoid to the starter motor, at the starter motor terminal. 4. Disconnect the ground cable from the powerhead frame to the starter motor. 5. Remove the clamp bolts, clamps and starter motor from the powerhead. To install: 6. Align the starter motor onto the powerhead and install the clamps and bolts. 7. Connect the ground cable from the powerhead frame lo the starter motor. 8. Connect the cable from the solenoid lo the starter motor, at the starter motor terminal. 9. Install the engine cowling. 10. Attach the positive (+) battery cable to the battery. Starter Solenoid TESTING Resistance Test • See Figures 71 and 78 The following test MUST beconducted with the solenoid removed from the powerhead. 0365762<) Fig. 77 This solenoid acts as a switch between the battery and starter motor. If the unit is found to be defective, it must be replaced with a marine approved solenoid 00657G21 Fig. 78 A cutaway drawing of a starting motor solenoid with major parts identified 1. Connect one test lead of a multimeter to each of the large solenoid terminals. 2. Connect the positive(+) lead from a fully charged 12-volt battery to the small solenoid terminal marked S. 3. Momentarily make contact with the ground lead trom the battery to the small solenoid terminal marked I. Ifa loud "click" sound is heard and the multi meter indi· cates continuity, the solenoid is in serviceable condition. If. however a "click" sound is not heard and/or the muftimeter does not indicate continuity, the solenoid is defective and must be replaced and only with a marine solenoid. Solenoid Voltage Test 1. Connect the voltmeter between the common powerhead ground and the No. 1 point 2. Turn the ignition key switch to the start position. 3. Observe the vollmeter. If there is no reading, the starting motor solenoid is defective and must be replaced. If a reading is indicated and a click sound is heard, the solenoid is functioning properly. :f 5-42 IGNITION AND ELECTRICAL SYSTEMS IGNITION ANO ELECTRICAL WIRING DIAGRAMS The lollowing diagrams represent lhe most popular models wilh lhe mosl popular optional equlpm1!11L Engine Wiring Diagram-1990-92 2.5, 3 HP Engine Wiring Diagram-1993 2.5, 3.3 HP STOI'SWITQ.t SECONO.AAY COil Engine Wiring Diagram--4, 5 HP (Serial #OA809601 and above) 1 • c.p.ettor Charging Coli o .. Trigger Con c-SIOP8u1toft QSalc-n -V.•tHJt Hu.s Commander 2000 Side Mount Remote Control with Key/Choke Switch-6, 8, 9.9, 15 HP (Serial #OA1971 12-0D280999) BLK •BLACK PUR •PURPLE RED •REO VEL • YELLOW '" OFF" BLK/YEL· BLK "RUN" RED · PUR "START" RED· PUR · YEUREO PUSH (CHOKE)' RED •YEL/BLK 'Key switch must be positioned to "RUN" OR "START" and key pushed In to actuate choke, for this continuity test. Engine Wiring Diagram-6, 8, 9.9, 10, 15 HP Manual Start with BLACK Stator (Serial #OD281000 and above) and 1998 20, 25 HP Manual Start with Mechanical Advance a -Stator b -Trigger c -Switch Box d -Ignition Coil Top Cylinder e -tgni\ion Coil Bottom Cylinder f -Stop Switch g -Emergency Stop Switch ......®- BLK = BLACK BRN = BROWN GRY : GRAY GRN =GREEN REO= REO WHT = WHITE YEL = YELLOW OS19SWI1 Engine Wiring Diagram-6, 8, 9.9, 10, 15 HP Electric Start with Tiller Handle Start Button with BLACK Stator (Serial #OD281 000 and above) and 1998 20, 25 HP Mechanical Advance a -Stator b -Trigger c -Switch Box d -Ignition Coil Top Cylinder e -Ignition Coil Bottom Cylinder f -Alternator Stator g -Rectifier .... h -Starter Motor i -Staner Solenoid J -Neutral Start Switch k -Start Switch I -Stop Switch m -Emergency Stop Switch BLK •Black BRN = Brown GRY = Gray GRN = Green REO = Red WHT zWhile YEL = Yellow 05195WI2 r­rn 0 .. :lJ 0 )> r­(/)(/) (/) -< ..rn$:: c.n I.a::..c.n .., .. , .. .,... r L.. G) :z .. 0 :z )> :z 0 rn "' Engine Wiring Diagr1998 6, 8, 9.9, 10, 15 HP Electric with am- Remote Control and BLACK Stator (Serial #OD281 000 and above) and 1998 20, 25 HP with Mechanical Advance .. r f .1' BU< • BLACKBRH •BROWN GAY" GRAY GRN •GREEN RED •REDWHT WHrTE•VEL eYELLOW a ·Stator g ·Rediller b ·Trigger h -Staner Motor c •Swtch Box i I -Staner Solenoid d • Ignition Coil Top Cyllnder J -Fuse Holder(20 Ampere Fuso)e • Ignition Coil Bonom Cylinder k -Choke Solenoid f • Alternator Stator I ·Wiring Harness ..115WI3 Engine Wiring Diagram-6, 8, 9.9, 10, 15, 20 JET, Manual Start CJ'I I with RED Stator (Serial #OD28 1000 and above) and 1999-00 20, ol::la en 25 HP " I I a ·Sta torb ·rigT ger e -SwitchBox d • Ignition Coil Bottom Cylinder e • tgnltlon Coli Top Cylinder f •Emergency Stop Switch g • Stop Swlt.ch (j) z: -i 0 z: :l> z: 0 rn r­rn ('") ('")::0 r-(/) (/) (/) :l> -< ---t -i m.. BLK •BLACK BAN •BROWN GAY •GRAY GAN •GREEN RED" R.ED WHT" WHill: VEL aYELLOW OS115Y/14 . , .. , Engine Wiring Diagram-6, 8, 9.9, 10, 15 HP Marathon and Sea Pro with Manual Start and RED Stator (Serial #OD28 l 000 and above) and 1999-00 20, 25 HP Work Model a -Statorb -Trigger e -SwitchBoxd -Ignition Coil Bonom Cylinder e -Ignition Coli Top Cylinderf -Stop Switch g -Emergency Stop Switch h -Alternator Stator BLK • BLACK= BRN c BROWN GRY = GRAY GRN., GREEN RED " RED WHT " WHrTE VEL = YELLOW O)lti\Yl$ Engine Wiring Diagram-6, 8, 9.9, 10, 15 HP Electric Start with Tiller Handle Start Button and RED Stator (Serial #OD281000 and above) and 1999-00 20 and 25 HP .. a · Statorb ·Trigger c • Switch Box d • Ignition Coil Bonom Cylinder e • Ignition Coil Top Cylinder f -Emergency Stop Switchg -Push Bunon Stop Switch •• h • Rec:tlflerI · Alternator Stator J • Start Swrtch k -Start Switch I • Start Solenoid m • 12 VOC Battery n • Starter Motor :z :z )> :z CJ mIm("")---1:::0 -(""))> I(/)-<(/)---1m 0519!\1'15 :5:(/) CJ1 I,c::.......... :-' Engine Wiring Diagram-6, 8, 9.9, 10, 15 HP Electric with Remote Control and RED Stator and Electric Start with Tiller Handle Start Button and RED Stator (Serial #00281 000 and above) and 1990-00 a ·Stator b-Trigger c • Switch Box d -Ignition Colt Bottom Cylinder e •Ignition Coil Top Cylinder f • Choke Solenoid g • Remote Control Harness 20, 25 HP BLK : BLACK BRN : BROWN GRY : GRAY GRN = GREENRED : RED WHT = WHITE VEL. = YELLOWh ·Fuse Holder (20 Ampere Fuse) I -Rectifier j •Alternator Stator k -Starter Solenoid I •12 VDC Battery m -Starter Motor li619SW17 Commander Remote Control Electric Start-6, 8, 9.9, 10, 15 HP (Serial #00281 000 and above) ·.. .. , __ _ / ·· -.. / ' --.. ; / t / ;' ' a -Ignition/Choke Switch b -Emergency Stop Switch c -Neutral Start Switch d -Tachometer/Accessories Harness Connector " BLACKBROWNGRAYGREENREDWHITEYELLOW05195W18 c.n I.r::­ coG):z -I 0z)>:z CJrnr­rnCJ-I ::0 CJ)>r­(/) -< (/) -I rns:(/) .-Commander 2000 Remote Control Manual-6, 8, 9.9, 10, 15 HP (Serial #00281000 and above) /.. -"\/// )BLK:BLACK VEL=YELLOW // )// /(,-"'-....,_ ,,, I\ \ , I I'\ 1 , I 1,y I I II I/".."-I I I..-/ " , I I...y ......_ 1 I I' ....... I I/ ....,_ I/ / " \/....._, " I/ " I..._..._, "-, ....... .............. a -RUN -OFF Switchb • Emergency Stop Switch c • Stop Switch Harness "' "' '\'\ \'\ /\\ / Iv II II II II II II J....._, I /'-....._,'-.1// 05195iYt.. Commander 2000 Remote Control Electric Start-6, 8, 9.9, 10, 15 HP (Serial #00281 000 and above) BLK =BLACK BRN = BROWN GRY = GRAY GRN = GREEN RED aRED WHT = WHITE VEL = YELLOW a •Ignition/Choke Switchb · Emergency Stop Switch c -Neutral Start Switch -.. d -Tachometer/Accessories Harness Connectore -Wiring Harness Connector z .. z )> z 0 rn r-rn 0 .. :::::0 -0 )> r-(/) -< (/) .. rn:5: 051951'120 (/) CJ1 I .. CD 5-50 IGNITION AND ELECTRICAL SYSTEMS Commander 3000 Panel Mount Control-6, 8, 9.9, 10, 15 HP (Serial #OD281000 and above) a -Neutral Interlock Switch b -Emergency Stop Switch ......_ ___ ___ _ Neutral InterlockSwitch REO::REO VEL= YELLOW 051951'121 Engine Wiring Diagram Manual Start-18, 18XD, 20, 25, 25XD, 25 Marathon, 25 Sea Pro HP (Serial #641671 3-00044026) .--------------; I.. '"'AA".. ' I ISOLA10ft8t.OCK 1 _______, VOt.TAG£ I REGUL,6,TOA I I I II I ---------------____J IGNITION srAciOA B-OTTOM.. C\1... iSTYL£ I} 0519SW22 ' '· IGNITION AND ELECTRICAL SYSTEMS 5-51 Engine Wiring Diagram Electric Start with Tiller Handle Button-18, 18XD, 20, 25, 25XD, 25 Marathon, 25 Sea Pro HP (Serial #641671 3-00044026) .. ....... ..··....•;,!J'"•'o : 0 t:'..;L SIAIQM I .........,/'' ' ,j : .. ........ .. ll . :t...l.."'''t ••••''"t"• 1 .... M..l.. ..O<.AO< ... I =.: iSlTtE)JL-----GAEEH•'Mflll---J 05195\173 Engine Wiring Diagram-18, I8XD, 20, 25, 25XD, 25 Marathon, 25 Sea Pro HP Electric Start with Remote Control (Serial #641671 3-00044026) 6ULlC1 ..N..CTOA lA1101.'t ..------c. ..u...,,,-.,.,.._ ---..II II I I I II I I I tu.c.. I I I COflI 80ITOM: tsiY.tn I------- GMf"'·-1&---..J :r I 5-52 IGNITION AND ELECTRICAL SYSTEMS Engine Wiring Diagram-18, 18XD, 20, 25, 25XD, 25 Marathon, 25 Sea Pro HP Electric Start with Ti1ler Handle and Ignition Key/Choke Panel (Serial #6416713-00044026) CHOJ{f SOUNotD ! .. i .. .-.AAOSIOII' ...._: OOD D!i195W31 05195W25 .-.. \ ._, Engine Wiring Diagram-18, 18XD, 20, 25, 25XD, 25 Marathon, 25 Sea Pro HP Ignition Key/Choke Panel (Serial #641671 3-0G044026) WIRING- 8 ::; ..0;' • QIgnition Key/Choke P'ilnel Wiring Di:zCJrnr­rn(")-;:::0("))>r-(/)-<(/)-;rns:(/)c.n ICl1 .. ,-- Engine Wiring Diagram-1994 112-1997 20, 25 HP Electric Start with Ti11er Handle Button/Electronic Advance .. A .f , .. J/ .. a -Stat or b -Trigger c -Ignition Coil Top Cylinder d -Ignition Coil Bottom Cylinder e -Emergency Stop Switch t -Stop Switch g -Rec1ifier h -Switch Box i -Charging Coils j -Starter Motork -Starter Solenoid I -S1art Button m12 VDC Battery n -Neutral Start Switch BLI< : BLACK BRN : BROWN GRY : GRAY GRN : GREEN RED : RE.D WHT : WHITE VEL : YELLOW l);llf>tl

  • 9Sl':'l9 c.n I c.n .. G) :z ---i 0 :z )> :z 0 rn r­rn 0 ---i :::0 0 )> r-(/) -< (/) ---i rn$:(/) Engine Wiring Diagram-30, 40 HP Manual Start (Serial #OG380074 and Below BUt : Bloc:k B I.. U • Blue BRN •&townGRV aGlllfGRN :Gt­ORN •OrangePNK • PinlcPUR •PurJ>1eRED:l&l\ • T..WKT •WiwttVEL •Y.scn.UT a UghtDRK ::: Dark (j) 1 · Eng!neT--2·T"""!' and P>otaclon 1Jocuie (TPII)3 • T nggo<4 •&slOt5 •Tcr.!W\0191 """ 6 •N..,..a S.., Sw1ta\7 • ..Sioos.ntc:>8 .Slop Buacn9 -Hom10· ..OtsGnatgtt.lod.J:e (CDMJ .. :01;5'tl30 Engine Wiring Diagram-30, 40 HP Electric Start with Tiller Handle Ignition (Serial #OG380074 and below) I E"'JJ''1.; -..==----(TPI.Q <6 •Slar..o tCOMI ·· ..-15 sea 94.3r 16 """' 17 Slan a..- BUt •Blo z: CJ rn r­rn 0 -t :n 0 )> r-(/) -< (/) -t rn .. (/) c.nlilt.. u.. c.n :r r'·· 5-56 IGNITION AND ELECTRICAL SYSTEMS Engine Wiring Diagram-30, 40 HP Electric Start with Tiller Handle Ignition (Serial #00380075 and above) ..j it A .. ...... ftiii(Ao.h!Jiol : .,..,_ Engine Wiring Diagram Electric Start-30, 40 HP (Serial #00380075 and above) 116195\\'33 ,..... . Engine Wiring Diagram Electric Start-30, 40 HP (Serial #00380074 and below) 0 I·EnglnelSer.sor2 •Tonir,..andl'roledon Moddo(TPM) 3. 7Jigge< 4 •SUloo5 .6 •Slar!o< AOIOy7 •12\/IJC Ba""ry8 •20l't.. 12&go oe >iaJT11!5St3-Fuei Enrcnmen1 \tatv.. , .. c...Oowi"'!IO ( CXlt.t) 8LJ( =BladeB&.U = llluoBRH •fltoiNn.CRY •GroyCRN •GrHnOAH •()range ..K • PinkPUR a Purp!R RED ::..TAN :Tan WHT ..Whl:ie va. :: Yetlow ur -..OAK =D.ark JlliSWlt Instrument/Lanyard Stop Switch Wiring Diagram-30, 40 HP (Serial #00044027 and above) BLK =Sl ackBLU =Sl ue eom =&own GRY ; Gray GRN = Greffl ORU =Orange PNK • Pink PUR • Purple REO = RedTAN = TanWHT = WhiteVEL = YellowUT = Ug ttt DRK = Dark a ·lgmbOrl/Oloke .MtCh b ·l..a.rPf;;roStep SV•t::n c -Leaa Net U;eo OnOU.boaro tr:siaila.MJ r..s;c ·Retainer e •Tad'lomefGause (Opnona..g ·Temp era•.:eGa"ll" h • Remote CcnuolI -Power HarnessCot:neaorj -C,O....;;tect Wires To:;)el herWith Screwat'-d Hex Nut [2Places). ApplyCltJrcks:l'K.f ..Neoprene :o Ccnnec:>onsand Sloicie-SlrNNo O¥e< Eacn Conned""'.. ·lead to Ool>ooal VcsuaJ \'larnmg Kit D51!1!W:l5 0 :z: ):> :z: CJ rn r­rn ('")---;:::0 ('") ):> r­(/) -< (/)---; rn.. (/) en I en ....... · ·' . ,.. , Instrument/Lanyard Stop Switch Wiring Diagram Dual Outboard- 30, 40 HP (Serial #OG044027 and above) (Cont.) BL.I( = Black BUJ = Blue BRH •Brown GRY =Gra y GRH =Groen ORH:Orang e PNJ( =Pink PUR = PurpleREO • RedTAH -: Tan WKT =White VEL = Yottow UT =UglltDRK =Dllf1< PORT INSTALLATION a •IQnoti:>'Mil:h c •lead Nol Used onOulboaro lnstaaatroOs d · Relil!ll er e • Tach:Jrneter I . Trmlndlica!Ogeg -Temperature Gauge h • Remo1e COnttOI 1 -Syncnroruzer Gauge i ·Synavonaer 6oJ< C5"9SW37 Instrument/Lanyard Stop Switch Wiring Diagram Dual Outboard- 30, 40 HP (Seria.l #OG044027 and above) (Cont.) k ·laf' yardJO•odeI . "'("Hamol;sm-Power Tr.m Harness Connecklr ..,. STARBOARDINSTALLATIO N 1 ConnectWires Togelher -Min Screw and Hex l>'ut (4Piaces);Apply a..cksolverliquid Neoprene to..and Slide RUbbe! Sleeve aver Each Conti... o -Leao 1n VI$' JalWarning Kll c<;..'Wll!. I c.n ca CJ) :z -f 0 :z )> :z 0 rn I rn 0 -; 0 )> r­C/) -< (/) -f rn$: (/) . ' -' Engine Wiring Diagram-30 Jet with 16 Amp Black Stator (Serial #OC 159200 and above) BLK= BLACK BLU ..BLUE BRN: BROWN GRY,. CRAY GR.N =GIIEEN PUR:PURPLE RED= RED TA.N :TAN WKT: WHrTE YEL: YELLOW LIT BLU =UCKT BLUE 1. Stator 2 ·Trigger 3 •SUlrter• •SUlrter Solenoid 5 •Vnnan • RegulatoriAoetlllor 6 •!!anary7 •EngneHameaa 8 ·Te1T1p8111ture G.. S.r!der 9 •Wamong Modulo 10.o.e.tlut Sw\ICII 11·Ennel>moorot v.,. 12·20..Fuse 13-SW>Id18ox 14• lgllftior\ Cool IIC) z CJ rn r-­rn("")--;::0 (""))> r-- (/) -< .. rn!5: (/) Ul Ul CD ,-, Engine Wiring Diagram-30 Jet with Tiller Handle and 16 Amp Black Stator (Serial #OC 159200 and above) BLK=BLACK BLU= BLUE BRN= BROWN GRY: GRAY GRN= GREEN PUR: PURPLE REO: REO TAN :TAN WHT:WHITE YEL: YELLOW LIT BLU = LIGHT BLUE I ·Stator 2 -Trigger 3 •Stancr 4 •Start er SOlenoid 5 •B&MI'f 6 -Engine Harnes$ 7 -Neutral Start Swltch 8 -Temperatvro Gauge Sen z 0 mI m 0 -1 :::IJ 0 ):> I (/) -< (/) -1 m s:(/) , ' Engine Wiring Diagram-40 HP Electric Start with 9 Amp Black Stator (Serial #OC1 59200 and above) BLK = Bl8ck BLU = Blue BRN:o Brown GRY " Gl"lly GRN " Green ORN " Orange PNK " Pink PUR = Purple RED = Rad Tan = TanWHT " White VEL = YellowUT = Light DRK = Dar.k 051..m3 Engine Wiring Diagram..O HP Electric Start with 16 Amp Black Stator (Serial #OC 159200 and above) BLK : BLACK BLUa BLUE BRH =BROWN GRY =GRAY GRH :GREEN PUR : PURPLE RED:RED TAN:TAN WHT= WHITE YEL= YELLOW LITBLU = UGHT BLUE 1 • Slil!«2-Tngger3 -Swill:n &x• •V<>llage ..5 -Starter6-Sr.anerSolef'lOIC7-s. .... .,8-T ,IIottomCoWo 9 • To Ta11 Femah!!Connec-.or onRen-.o1e Conuol Hamess PLlg1o-T.,_,l\R GougeSetlder11-..Module 12-Ovem ... ,Module 18 1 9 .. / * / 8 / .te/, .. /" 910--;" I 13-Low.. SMith1.C;• Coil No I1..Coi1No.21&-eo• No 311·CodN'o.4 120Am .>e"' Fuse1Fus. Ennti'lmer JVat¥!! CSJ9S.\44 G) z: -I 0 z: )> z: 0 rTl r­rTl C) -I ::D C) )> r­(/) -< (/) -I rn .. (/) CJ'I IC') .,, Engine Wiring Diagram-40 HP Electric Start with 16 Amp Red Stator (Serial #OC159200 and above) BLK = Black BLU =Blue BRN = Brown GRY = Gray GRN = Gr.,.,n ORN = Orang.> PNK = Pink PUR = Purple REO = Red Tan = Tan WHT = White VEL = Yellow LIT : Light OAK =Dark a • 16 Ampore Sta.tor b • Stator Adaotor c • Voltage Regulator d • Swijch Box e -Ground Connection OS1!i$YI45 Engine Wiring Diagram-40 HP Electric Start, Tiller H..ndle with 16 Amp Black Stator (Serial #OC 159200 and above) BLK = BLACK BLU = BLUE BRN = BROWN GRY: GRAY GRN=GREEN PUR = PURPLE REO = RED TAN = TAN WHT= WHITE YEL = YELLOW UT BLU =L.IGHT BLUE 1 • Sta.tcr 2 ·Tri gger 3 •Sw\tehBox 4 · Voltage Rcguta,c>r 5 · Starter 6.. Starter Solcnoi z 0 rn r-rn ("') ___, ("') )> r-(/)-<(/) ___, rns:(/) ·1 : ., Engine Wiring Diagram-40 HP Electric Start, Tiller Handle with 16 Amp Red Stator (Serial #OC159200 and above) BLK = Black BLU = Blue BRN =Btown GRY = Gray GRN "Green ORN = Orange PNK "' Pink PUR = Purple RED = RedTan =Tan WHT = White VEL " YellowLIT ,. Light ORK = Oa.rk a •18 Ampere Stator b •Sla1.orAdat>tor c •Voftag.eRegulator d •SwitcnBox e •GroundConnection .. ;b' C519SVI..I Engine Wiring Diagram-40 HP Manual Start with Black Stator (Serial #OCI 59200 and above) BLK = Black BLU = Blue BAN = Brown GAY = Gray GAN = Green ORN : Orange PNK = Pink PUR = Purple RED = Red TAN = Tan WHT = White VEL = Yellow LIT:: Light OA.K = Dark ""' TE"MINAl &oat a '0STOPSW1TCH SWITCH TOBOTTOM COWl. OISI96W :z 0 rnr­rn 0 .. :::0 0 )>r­(/) -< (/) .. rn s: (/) c.n I0) w -.. Engine Wiring Diagram-40 HP Manual Start with Red Stator (Serial #OC 159200 and above) BLK = BIIICII BLU =Blue BRN = Brown GAY =Gtay GRN = Green ORN = OrangePNK =Pi nk PUR = Purple RED = RedTan =Ten WHT : While VEl : Yellow LIT = Light DRK = Dark a •Lighting Coil Stat.or b •BLUEMIHITE Lead -Not Used c. Plug d • Terminal Block e • Stator A..or I ·Switch Box g ·GrounoConnection ......___ a .._d/ e OS191W.9 Power Trim Wiring Diagrarn-30 Jet, 40 ( 4-Cylinder) BP (Serial #OC1 59200 and above) ....,.,..... BLK " Black BLU " Biue BAN " Br-n GAY • Gray GAN " Green OAN • Orange PNK,. Pink PUR oPurple RED " Red TAN " Ten WHT •White VEL • Yellow LIT aLight OAK"' Dark . ., ..=NJWo;Tl.. r--n --,.. l I: : TfUWt.I0T0'l I I I I, ______ OIQM MNtHU' (:(!Nt(i Olt9SW50 c.n I en .. G') z -i 0 z )> z 0 rn r­rn 0 -i :::0 0 )>r­(/) -<(/)-i rns:(/) :. , Commander 2000 Side Mount Remote Control Power Trimffilt Electric Start with Warning Hom Vliring Diagram-30 Jet, 40 (4-Cylinder) HP (Serial #OC1 59200 and above) BLK • Bl-.ck BLU o Blue BAN = Brown GAY = Gray GAN aG...,. OAN = 0 111n ge PNK " Pink PUR : Purple RED=Red TAN = Tan wm •White YEL • Yellow liT =L.ight OAK =Dllf1< a • 11'\lboni'Chol z0 m..mC)-I :::0-C)::t> .. (/)-< (/)-Ims:1.61 9511!>2 (/) C1'l IC7)C1'l ,-' Panel Mount Remote Control Wiring Diagram-30 Jet, 40 (4-Cylinder) HP (Serial #OC159200 and above) •••.w.,o-tlu.Mot.t Jl;tO.lPUII. BLK = Black BLU ..Blue BRN = Brown GRY = Gray GRN = Green ORN = Orange PNK = Pink PUR = Purple RED = Red TAN = Tan WHT = White VEL = Yellow LIT = Light DRK = Dark ,.._/ ./ ' / ' .... .-:::' .. /....? I ....._ , _,..... ' ,_"/' IIIf III e I II • II I /I io _,_ I I I/ ' --I I.. ---I II -----"> I I ,I --...... ;,.,.. ', I I I- .., '-., I I r, I 1' "" I 1'"" I\ \ I f\ I I \ t.............I II / //' __ .... 05195'1153 Remote Key Switch and Warning Horn-30 Jet, 40 (4-..ylinder) HP (Serial #OC 159200 and above) BLK = Black BLU = Blue BAN = Brown GRY = Gray GRN = Green ORN = Orange PNK = Pink PUR = Purple RED =Red TAN = Tan WHT = White VEL = Yellow LIT = Light OAK = Dark KEY SWITCH '.. 05195'1154 c.n I en en G) :z -I 0 z )> z 0 rn I rn 0 -I :0 0 )> I (/) -< (/) -I rns: (/) ·..\ Engine Wiring Diagram-1997 40 and 55 HP MH (Serial #OG53130 I and above) and 75 HP with CDM and Manual Start (1 -2-3 Firing Order) 1-t .. Y y X t I ---b £lE-"'"TAAC&t.. ""'r'E=----IlUC [-·->-·-·../ I••A.T8t....UNII,T /d ,.111.. PPl-<+-..... a -Trtggc1 b-Stator c • Tl!mpetalllte Swildl I •Lanya1d SICll>SWIIchV • Rev. Lfmiterh ·COMJ3 •d -Warning Hem I ·COMf2 e •Push-Bunon Slop SWIIdl I -COMII c 0111.WI6 Engine Wiring Diagram-40, 50, 60 HP EO (Serial #OG53 1301 and above) a-Trigger b • Sta1or e • Remote Control d •20 AmpFuse c-SlanerI -Fuel Enrichment Solenoid g •Oil levelSWllchh -Head Temp.Switch b c d/ / /9 h·-·..>-·-·.. / I -12 VBanoryI · Stan Solonold k•Vortogo Regula lor I -Rev. Llmher m-COMI3 n · COM 12o -COM 11 1 / lr.lt!l'.. 0:z)>:z D mr­m0-; 0)>r­(/)-<(/)-; m..(/) c.n I m ....... :-' •v .., Engine Wiring Diagram-40, 50 HP EHPTO (Serial #OG53 130 1 and above) a· Trigger b ·Stator c · Key Switch d • Warning Hom d e •Push Button Stop Switch f • lanyard Switch g •Remote Control h • 20Amp Fuse i · Cowl Mounted Trim Swlich j •Trim·Oown Relay k • Trim-Up Relay I ·Starter I e I kiiijUL,lA m..Fuel Enrichment Sotenold n ·TrimPumpo • Oil level Swiich p • Head Temperature Swlten q • 12 Volt Battery r • Neutral Start Switch s •Start Solenoid t • Voltage Regulator u · Rev. Umiter v ·COM 3 W·COM2 X·COM I ll;ISSWS7 Engine Wiring Diagram-40, 50, 60 HP EPTO (Serial #,OG53 1301 and above) ·-.. (]'·.. .. rxn • .--.;:Q=-1rfi /k ··..::::.. /I,_,-+>-•-1.. a· Trigger b · Stator c -Remote Control d •20 Amp Fuse e • Cowl Mounted Trim Switch r • Trim·Oown Retey Switch g •Trim-Up Relay Switch h •Staner I •Tnm Pump J •Fuel En::chment Solenoid k • Oil Level Switch I · Head Temp. Switch m •12V Battery n ·Stan Solenoid o • Voltage Reguialor p · Rev. Umiter q ·CDIIH3 r ·COM-2 s · COMI1 051S5Vi58 CJ1 I en co G) z -i 0 z :l> z CJ rn r­rn ("") -i:::0 ("") :l> r-(/) -< (/) -i rn $: (/) Engine Wiring Diagram-60 HP EHPTO (Serial #00531301 and above) a•Key Switch b • Warning Hom c •N eut ra lStart Switch d•T11lerHandle Trim Switch o • Push-ButtonStop Sw..ch I · Lanyard Slop Switch 9·Starter h •Trim-Up Relayf •Trlm·Down Relay f •Cowl Mounted Trim Switch k • 20 Amp Fuse I ·Trim Pump m· Fuel Enrichment Solenoid /0,_.......>-·-·..-..- n•Oil levelSwitch o •HeadTemp. Switch p •12V Batteryq • Start Solenoid r •Voltage Regulator s •Rev. Limiter t ·COMH3 u·COMH2 v ·COM Ht w·Trigger x ·Stator y •Remote Control /9 CSt95W$9 Engine Wiring Diagram-50, 60 HP Electric Start/Rectifier (Serial #0000750 and above) RECTIFIER MODELS a· Sunorb. Tnwor c•SWik.l"' BoxCl •Ignition Co11 Cylinder No. 1 o · lgni 1io n Coli Cylindet No. 2 t · Ignition Coil Cylinder No. 3 g ·Stll16r Motor h •Starter Sol•noid I · Rec.jfier I ·Fuse H.r 120 Arno Fuu)k.llatlO!y1 •Winng Hamt.u Connector m• Enrietvn.n1VAlve n ·Ttmpe.atureSwitch 0 •LOW OilWatnlng MOduli p ·Low OilS.Mor OSI961'161 G1 :z --I 0 :z ):> :z 0 rnr­rn ("'") --1 ::::0 ("'") ):> r-(1) -< (/) --1 rn s:(/) Ul en (C) 5-70 IGNITION AND ELECTRICAL SYSTEMS Power Tilt-40, 50, 55, 60 HP Electric Start with Warning Horn (Serial #0053 1301 and above) a -Ignition/Choke Switch c -Neutral Start SwiiC!l d -Tachomeler/Accessories Harness e -Wiring Harness Connector I •Warning Hom g • Trimlli.. Swilch h • Wire Retainer i -Control Handle I -Trim Harness Bushingk -Trim Harness Connector I •Lead to Trim Indicator Gauge Power Trim Wiring Diagram-50, 60 HP (Serial #D000750 and above) a-PowerTrim b -PowerTrim Relay c -Englne Sfaner Mot01 Soloooid d. Ree1ffio< e •Cowl .wnlOd Trim $-M((;h I •RtcJ {•) Battery Cabf• g • ;.,.. HOIOO< (20 ...., Fuse) "' •Engine w.nno tia.. Comeet!)r i •Rctmoto Cocrtrol w.nno Hamess Corftector GRN r __ __ , I l: Q : l I I l L -----.J BLK oBLACK BLU • BLUE BAN • BROWN GAY • GREY GRN • GREEN PUR • PURPLE REO • REO TAN • TAN WHT • WHITE YEL • YELLOW LIT oLIGHT 05195W64 BLK • BLACK BLU • BLUE BAN • BROWN GAY • GREY GRN • GREEN PUR • PURPLE RED • RED TAN • TAN WHT • WHITE VEL • YELLOW LIT • LIGHT 051951\"60 . '··..Engine Wiring Diagram-50, 60HP Electric Start/Regulator (Serial #D000750 and above) REGULATOR MODa.S ••Slalo ..p- ..OII - BLK • BLACK BLU • BLUE BRN • BROWN GRY • GREY GRN • GREEN PUR • PURPLE RED • RED TAN • TANWKT • WHITE VEL • YELLOWUT • UGKT !6 1 .. Engine Wiring Diagram-55HP Manual Start (Serial #D000750 and above) a· Sl.li!Otb • Toss« c -SWI.&cn BoxO· ..CaoiC..No.l• · lgnilionCcolo,w-No . 2I ·lgnilon Cooi ..No.3g -TemoerDJr• SWic:tln-o..m... w_.._• -Wamng HomI -s:... a.. -.. •t.anp."ttSlop S..O cn BLK • BLACK BLU • BLUE BRN • BROWN GRY • GREY GRN • GREEN PUR • PURPLE R.ED •RED TAN • TAN WKT • WHITE YEL • YELLOW UT • UGKT ..; ! ..f _L ... ,.,.)'{?'"" 011 .. G) :z -t 0 :z :t> :z 0 rn r­rn 0 --; 0 :t> r-(/) -< (/) --; rn s:(/) c.n I............ .-.. Engine Wiring Diagram-1987-93 70, 75, 75 Marathon, 75XD, 75 Sea Pro, 80, 90HP with Low OilWarning Module a.Stalo<'b ·Trigge r c .SWI!ctl Box d •Ignition Coi Cylinder No. I e •lgnrtionCoi Cylinder No. 2 I •l.on CoolCyvnder No. 3 g •MelCUI)I [nil} Slop..h -Sl:aJtf'rf\l..oto r1 •Slatt erSooenc.d : ; j ·VOltage.tl>I'IRIICii&tk •FuseHolder (20 Amp FUS41) I .BanefYm·WiringHarnessConnector " •EnrichmenaVlllYe o • TermirloolBlock BLK • BLACK BlU• BlUE BRN • BROWNGRY • GRAY GRN • GREENPUR • PURPL£ RED •RED TAN • TAN VIO •V1ot.£TWKT • WHITEVEl • YELLOW p •Temper.b"Ure SW!:Icn -Opeos [1 70'F ± e• (77"C ± 8'))aoses [190'F ± a• (aa>C =8')1 q •Low 011 WarningMcd.ole r ·Low Oil SeAleh-Opens [170'F =s· (77"C ± 8')1Closes (190'F = 8' (88'C ± 8')! q-Tes!IIU!o n r 'Low Oilsensor ;61S5'h'56 c.n I .....,N G) :z: .. 0 z ::t> z 0 rn r­rn(")--1:::0 (") ::t> r-(/) -::: (/) --1 rns: (/) ,-.. Engine Wiring Diagram-1987-93 70, 75, 75 Marathon, 75XD, 75 Sea Pro, 80, 90 HP with Voltage Regulator/Rectifier a·Starorb • TriggeaaBlocto q ·T.1Ure SW!tch -Clperls (170'F = 8' (77-C ± 8")) Closes (190'F ± a• (88"C = 8'))r ·LowOIWarrW!Q -s -Low OilSenscr 1lSI!6"0/68 G) :z --1 0 :z :t> z: CJ rn r­rn CJ --1 ::D CJ :t> r-(/) -< (/) --1 rn .. (/) c.n I ...... w ,-' Engine Wiring Diagram-1988-93 100, 115 HP with Small Voltage Regulator/Rectifier BLK • BLACK BLU • BLUE BAN • BROWNGRY • GRAY GRN • GREEN PUR • PURPLERED • RED TAN • TAN VEL • YELLOW a-Stator b ·Trigger c ·Switch Box Ik q I · Sla..etSolenoid d •lgn..lon Coil CyRnder No. t a•Ignition Coil Cylinder No.2 f • Ignition Coil Cylinder No.3 g •Ignition Coil Cyflnder No.4 h •Mercury Swkcn k •Vollage Regulalor/Rectitier I •20 Amp Fuse m· Batteryn-Fuel Enrichment Valve o · TerminaJ Block p • OvemeatSen sor q •Wamlng Modulo 1 •Starter Motor r • Low OR Sen sor (Float) OSI9SIY&.l Power Trim System Wiring Diagram-1987-93 70, 'J5, 75 Marathon, 75XD, 75 Sea Pro, 80, 90 HP with Commander 2000 Remote Control '" BLK • BLACK BLU • BLUE GRN • GREEN RED • RED WHT • WHITE GRN or,_J ___ , I I I I 1 a I I I f I I a •Power Trim Pump Motor b •Trim Solenoid ·up· c •Trim Solenoid "DOWN" d • Engine Starter Motor Solenoid e · Red (•) Battery Cable I -Fuse Holder (20 Amp Fuse) 9 •Engino Wiring Harness Comector h.. Remote Control Wiring Harness Connector OS19SI'I70 c.n I....... .. G):z -I 0:z )> :z 0rnr­rn 0-I :D 0)> r-C/) -< (/) -I rn ..(/) ,·.. PowerTrim System Wiring Diagram-1987-93 70, 75, 75 Marathon, 75XD, 75 Sea Pro, 80, 90 HP with Commander Remote Control a •Power Tnm Pump Ua!O< b · TrimSGienatd "UP" c-TnmSclenOd •oowN"d •Engine Starter r.Aooo r .. BLJ( • BLACK BLU 8 BLUE GRN •G.. PUR • PURPLE RED • RED WHT •wtiTE e ·FuseHolder (20 .. Fuse) I ·Red(•)Banetrol CSI!&\71 PowerTrim System Wiring Diagram-1 988-93 100, 115 HP with Commander 2000 Remote Control :: e •·-Tnm ..Motolb •T!Wn Solenoid V I"" c • TnmSolenood"DOWN" •• Red(+) Bane •RemoteConl10I 'lllfnng HamessComec:tor C6 195'1m G) :z -I 0 :z )> :z 0 rn r­rn ("") -I ::0 ("") )> r-(/) -< (/) --1 rns: (/) CJI I CJI :-' Engine Wiring Diagram-] 994-95 65 JET (1-2-3 Firing Order) BLK = BLACK BLU = BLUE BRN = BROWN GRY = GRAY GRN:GREEN PUR = PURPLE REO : REO TAN:TAN VlO= VIOLET WHT: WHITE YEL: YELLOW a · Slater b •Tnggor c • Slarter o • Staner Sotenold e ·20 Amp ere F.u se1 · t2 Vob Batteryg Engine Harnessh low Oil SensorI •••Warning Module .. J •TemperaMc SWitch k • Enm:hment Valve I • Voltage Regulator m· RPM L!m1ter n · Switch Box o • Ignition Coilif3 Cylinder p •Ignition Coil:n Cylinder q •lgnttlon Co1l #1 Cylinder r • Terminal Block 061951'173 Engine Wiring Diagram-1 996 65 JETHP (1-2-3 Firing Order) BLK= BLACK BLU = BLUE BRN= BROWN GRY =GRAY GRN=GREEN PUR : PURPLE REO : REO TAN = TAN VIO=VIOLET WHT:WHITE YEL:YELLOW a· Stator b • Tngg er c · Starter d · Statler Solenoid e • 20 Ampere Fuse f • 12 Volt Battery g •Engine Harnessh •Low Oft Sensor I •Warning Module 6..b n j •Temperature Switcn k •Enrlct.men! Valve I •Voltage Regulator/Rectifier m· RPM Llmner n · Switch Box o ·Ignition Coil.tl3 Cyrtnder p •lgnitton Coli#'2 Cylinder q •Igni ti on Coil #1 Cylinder r •Terminal Block 115l95W74 CJ1 I -..J en G) z: -I 0 z: ):> z: 0 rn r­m ('") -I :::0 ('") ):> r­(/) -< (/) -I m .. (/) Engine Wiring Diagram-1 994-95 75, 90HP (1-3-2 Firing Order) BLK : BLACK BLU = BLUE BRN: BROWN GAY : GRAY GRN =GREEN PUR = PURPLE RED = RED TAN=TAN VIO=VIOLET WHT= WHITE YEL:YELLOW a· Sta1or b • Tflggerc • Slarter d • Slarter Solenoid e • 20 Ampere Fuse f • 12 Voh Bauory 9 ·Engine Harness h • Low Oil Switch I • Waming Module ; ..-, J • Temperature Switch .. •Termillal Block I · Enrichmeni Valve m-Voltage Regulator/Rectifier n -Swftch Box o • Ignition Cot! #3 Cylind er p • Ignition Coil#2 Cylinder q • Ignition Cotl #1 Cylinder OS19SW75 Engine Wiring Diagram-1996 75, 90HP (1-2-3 Firing Order) BLKc BLACK BLU=BLUE BRN: BROWN GAY = GRAY GRN:GREEN PUR = PURPLE RED=RED TAN= TAN VIO=VIOLET WHT:WHtTE YELcYELLOW a. Stator b · Trigger c · S!Jlrier d • Slarter Solenoid e • 20 Ampere Fvse r . 12 Voh Banery 9 · Engine Harnessh • Low Ofl Swiich1 • Warning Module i . J ·iemperature Switch k • Terminal Block I ·E nrichmenl Valve m·Vollage Reguta1or/Rec1iher n • Sw1tch Box o -lgnillon Coill/3 CyiJnder p • lgnilton Coit/12 Cylinder q • Ignition Coil.1'1 Cylinder --i z: 0 rn I rn C)--i ::::xJ-C))> I (/) -< (/) --i rn s:(/) OSI9SW76 CJ'I I...._......_.. ,· ' Engine Wiring Diagram-1994-95 75 HP (1 -2-3 Firing Order) BLK= BLACK BLU= BLUE BRN= BROWN GAY = GRAY GRN =GREEN PUR = PURPLE RED = REO TAN =TAN V10= VlO LET YffiT,.YffiiTE YEL= YELLOW a·Statorb • Tnggerc · Swi!ch Box<1 • lgni1ion Cod Cylinder #1 e -lgn.ion Coil Cyfrnder#2I -lgmtion Coil Cyllllder #3 d b il: k j ... r+ i _,, g g -EmergencyStoo SWitch hStop& ttonJ • Wami'>g Hom j -Temoorature Sv.-rtch l< -RPMUrniter QST.M'h7J Engine Wiring Diagram-1996 75 HP (l-2-3 Firing Order) BLK=BLACK BLU :BLUE BAA=BROWN GRY : GRAY GRN =GREEN PUR: PURPLE RED= RED TAN :TAN VIO= VIOLET WKT =WHITE YEL: YELLOW a·Statorb • Tngger c -S"11ch Boxd • Ignition C01l Cylinder #I e -Ignition Co.. Cylinder 1"2I -lg!\ition Coli CylinderrJ ... "" c• k •, li --' 'h _, .. g -Emergency Stop Switch h -StopBu!ton I • Warning Hom 1 -Temnerature SWttch i< -RPMI.J :z 0 m r­m 0 --I :::0 0 )> r­(/) -< (/) --I ms: (/) Engine Wiring Diagram -1994-96 80 JET, 100, 11 5, 125 HP BLK: BLACK BlU.. BLUE BRN= BROWN GRY =GRAY GRN= GREEN PUR =PURPlE RED = RED TAN u TANV10 =VIOLET WNT:WHITE YELsYELLOW a ·StaiD-T c ·Stonerd • S:aner Soler-. e. 12VoltBanery' ·eng.,. Harness g •Vlamlng Moca1e n ·.._ OilsensorI •Tem;>e!er J •qp-.AUT'1Qfm-qoalon Cot ,.C}tnOor.. ••CnCot =3 .. o.Jgt-->eneot nC)lnoero • 1cer q .S...lCh ao.' ..a.oa. ..;99/m Engine Wiring Diagram-1997 65 JET w1tb CDM (1 -2-3 Firing Order) BLK=BLAC! z 0 rn I rn 0 --;::0-0 ::t> I (/) -< (/) --; rns: (/) c.n I .......CD .. , Engine Wiring Diagram -1997 75, 90HP with CDM (1-2-3 Firing Order) BLK: BLACK BLU= BLUE BRN= BROWH GRY •GRAY GRH= GREEH PUR :PURPLE RED=REDTAH :T AH VIO:VIOL.ET WHT :wtiiTE YEL z YB.l.OW c d .. b t I -; } : .. .....,. .. J J lp ' 1\JJ, ,. .. , = L=..I f! ! • I I II I ; . . .. I . ,I • ' I I II ' j . . ..-··..• lo -... I I ---g -----. I ':t ' --4--h. . •• •. . k r-•.. ..... ..-'> · -, · ·· --' I I • ... ---I : ' . .._ .;::::::>-.. -JI I ....., ; _ '5o. . -1 II ------<: a. Tr!gg 81b • Sta!or c·Remote Control a • 20AmpereFuse e •StanerI •StanerSOJenoo:l g -12 Vo..Batt"'Y h • Fuel EMChment Solenoocl I • Head Temperature :.. · m .. ·------=t-. -I 1 • Oil WaJJW>Q Modulek •Ool Le-.te! SwllehI · Engine81cx:k ro-EJeaJ;cai PJa:e n·CDM-"3 C·CDM#2 I>·CDM#1 q · lll>llage Aegula!or OSJ!i>Aal Engine Wiring Diagrarn-1997 80JET, 100, 115, 125 HP with COM ..:....: ..GII Y2 GIIA Y J c d eGRH=GAEEN f @PUR =PURPLE D 1 m;j . I, --·-·r" 0 --p a·Triggerb·Staler c •Remo!e Coolrof o ·TrimSwi!dl• • To Remote Tnm SWrtc:nf • Ocmn Relay9 · Up Relayh· Sl.arte.r• ·Trim PumpI ·SlanerSo!encodk • 12 V<'! 8a:tetyI •F<* Er,flehmentSooenood .· --. -.!l._.,s --.. r m·Tempe.-.mreSffltd: .n • OJWarnitlg Module ;o • RPMlmi:er Moclul& p · Oll.evel Swil<:h q · Engft Bbckr •E!ectnca1?tare s ·C0..., •4 t •COMI:l u·CO...,::Z v ·COM 11 w •VoltageReguia:or 161 16?1.>2 Ul I 00 C) G) :z .. 0 :z :x> :z 0 rn r­rn ("") .. ::IJ ("") :x> r-(/)-<(/) ..rn ..(/) .. .-' . ' .. , Engine Wiring Diagram-1991-92 135, 150, 175 HP with 16 AMP Stator ..O AMP. ron TO COWL MOUNT£0T1l TSWITCH 12VBAnE 05195WB3 Engine Wiring Diagram-1991-92 135, 150, 175, 200 HP with 40 AMP Stator COIL N0 2 0..! N NO, 3COfl NO. 6 •200ModEH (SIN OC291560..000172•U) EQuipped with lc!la StabiliLer. .o .. CON1'ROL BOXCONNECTOR FUSETO COWL MOUNTED TILT SWITCH 12 05195W84 G) z -1 0 z :t> z 0 m r­m 0 -1 :.0 0 :t>r-(/)-<(/)-1 m$.::(/) c.n I co ..... .-... ' . . , Engine Witing Diagram-1991-92 135, 150, 175 HP with 40 AMP Stator ' . .,. I lEAMINALBLOCK § ;y' TRIMo4 0 AMP.REGULATOR q,,. 12 vBAnE Y 110195\'ISS Engine Wiring Diagram-1 991-92 XR4, Magnum IL (Serial #C254932and above) SHin .. ftESISToMODUlECOil. HO. 6 • EqtJipped with Idle Stabftizcr '·• 40 AMP.RECULATOR .. o.. CONT OL BOX ....INSTtL CONN£C'TOA " " !l " !:01951'/S6 Ul I= NG) z-I 0z):> zCJ mIm('"') -1:0('"') ):> I(/)-<(/) -I ms:(/) .. ... ..,··..Engine Wiring Diagram-1991-92 XR4, Magnum II with Idle Stabilizer (Serial #C254932 and above) .. Q"..:0:.. COIL JrWO. e · Equ.pped w•th ldleSta.biliz.. CA.. .. :; oa.ocx COfiTaot .ax 10·" . 40 "<.t 12 (51!l5\'l'l!7 Engine Wiring Diagram-XR4, Magnum II {Serial #C247591-C25493 1) ....) ' Q! R£mt001IIOOUl.E :1' 001.. NO 5•E:Qutpped'-whh fdle Stabili::..r/AOval'lCe Module 7 . .. ' ...... 7 •, • 2 40 ...... G) z-i 0z:t> zCJrnr­rn 0-i :0 0)>r-C/) -< (/) -irns:(/)U'l I00 w ·NOTE; 175EFI Models(S/N 00001•14 on up) areoqulppedwilh Spark A. ., n ' ' ,,., I "j '-, \.,. ··r \ ----I PUMP AND MOTOR l 1 II I .. .. I IH 1 I..= I I"" !:: , I ./J ' -.. . I "''-! ...... ..(/.. BOTTOM COWL TilT SWITCH ffil.. Engine Wiring Diagram-1992-00 135, 150 HP SLK:BlACK SLU=BI..UEBRN: BROWN CAY: CRAY GRN: GREENPUR: PURPLE RED:RED TA.N:TAN VIO : VIOLETWHT: WHITE YEL: YEU.OW 24 1 ·•O..Stal!X2 •S!aner3-W>alM• ·OiiTanl< Caps-..eStobiiz er6Rc:utionaJSensor7 •Ennc:tvnen<\lalYo& •Thfrpota.n> GaugeSender9 .Con:rol Box !I\Slr\JmMI (CcMec:oc<10.Engin& lfamessII· !2VBa111!ry12sSolenoid ·..Ou1e< S'MXh Box 9 I 11 14·T-elodt15-Watsr T-=""&MlCh 16-\lcl&age ..17·Col• 118-Cailo 319-Cailt52D-Ccill 6 21-CoiU 22-Coi. 2 ..-SWil z: CJ rn I rn C) -I ::::0 C) )::> I (/) -< (/) -I rn .. (/) c.n I Q) c.n , .. Engine Wiring Diagram-1992-QO XR6, Magnum ill, 175 HP BLK : BLACK SLU:BUIE SRHcBftO WNGRYaGRA YGIIN =GREENPURe PURPlER£D ;R ED TAN aTAN VIO:VI OLET WKT:WHITE YEL. cYELLOW ...... ' 1 •.01\mpeft! SlaiOr2.s:a.w3·..4 •OiiTenlo: C... S·ldlot .. 6--7- ..8 · T._..,..Goougo 5onder9 •Coood Box.._.,.,.,.Conneca>tlO.EogN Hom11 ·1ZVB£1ory12·s-.Solonoicl 1a..t Sw'll:hBox 1··-IS.W_T..._.....,.. _,r,.....,_.. ! / 25 19 9 11 1o 17·Coil fl1&-Coilf 3Ill-CoifS 20-CoU6 21-Coi•. 22·CCU2 23·,,_SM:::hBox 24·Tri$1ge< 25·zr,.:snl ll- 27·20Atrpe:e Fuse 1111l5'Alll Engine Wiring Diagram-1992-QO 200 HP · BLK2 BLAC« BLU ; BLUE BRH: BROWN GR Y:GltA Y GRH:GR EEN PUR:P.. RED:RED TAN ..TAN VIO=VIOLET WHT=WHITEYEL..YELLow I ·.O ..SlDw 2.Slatlor3·............4-Oii T-Cops ·ldleSiobiizO< 6· -7 ·-a. Tomperu.n Gaugt 9 •CcnlroiBox lnsl:\lnOinlCcnneaor10.eng;..Hamtssll· 12VOI! BDooy 12·-13-0 z 0 rn .... rn ("")-I:0 ("") )::> .... (/) -< (/) -I n15: (/) Engine Wiring Diagram-1992-00 200 HP Carbureted (Serial #00077248-0D 1227 46) 1 •40A/npel8Sta!or 2 • Stanet 3 .W8ming Module • ·OiiCap 5 Motion Sensor6 •FuelEnrichmenl Valve 7 • Ten..,..,atu,.GaugeSender 8 ·Starter Solenald 9 • 20Ampent Fuse 10.Engine Harness 11-Battery12Von.g,& Regulator 5 11 -1 2 ., 13-WalllfTemperawre Swilch 14-Outer s Bolt 15-115 Col 16-13 Col 17-11 Col 18 -f6Coi 19-« Col 20-112Coi21· Inner Swllctl Box 22·Advance Module• 23-Trigger•Refer 1D Service Bullet in 91·35 051!llll!l5 Engine Wiring Diagram-1992-00 150, 175, 200, 225 HP Pro Max, Super Magnum 8LK =8L.Aa( RED"' RED BLUzBLU£ TAN :TAH BRH = BIIOWN VIO "'VIOLET GRY zGRAY wt1T"WKrE GRN:GIIE£N VEL=YELL OW PUR zPURPLE231--..-2·..3- ·s-S- litT.._.....,6 -Secwno: ..Urlot 7 ·F....,..,.,.. .._ 9-121!:111-.y10---.-11·-Senot"og..-12-W.. ..MIIor 13-__ _ 14-kJ... ... 17·2D..Fuse(il>Trim-...q18-a.--eo. l g..ft--«sa.ilr::!\ b. T -21-Siuo<22-0il-c.p23-TO....2 ...,.,_...... _ 2s-Coit I..Col02Z7-Colo3 2&-Coil,... :5-Coiles :z: )> :z: CJrnr-rn0-f :::0-0)> r-(/) -< (/) -frn..(/) IS.&.gone ,_ c:.1""""1 10 ..(2) »Col•s CSt!llil'l6 (,J'I Ico...... ,., Engine Wiring Diagram-1 992-00 200 HP EFI, 200 HP Pro Max, Super Magnum with Detonation Module 1 •OelOnafio!"' Son&Of" 2 .. Detonation Modulo3 • WotorTompo"'"""Switch 4 • Wamlt\g Modukl 5 • Stltter Solenoid6 •Starter Molor 1 . Aif Tempemtute Sensor 8 • ElectronicConlrol Urit 9 • Fue!Pvmp 10. 1nje:;tors 13-W.101 Senelng Warriing Mo6ule 14· Waler S.pora..ng Flltor 1 s-Throttle Pos.i,ion Sensor16-IdleSt&bltizor17-Engine HomenConnotlor 8U(., BLACK BLU= BLUE BANe BROWNGRYc GRAY GAN=GAEEN PUA=PUAPLEAED=REOTAN=TAN VlO=VlOLETWHT:WHITEYEL=YELLOW 18• VO!IIIgO RA!guUII'1: 22·Triij90r2•·o;t TonkCap2$-Tempera ureS.ns.or 28-Coill 1 21· Col 11 22'SI-Coill432· To lempenUure Gauge 06\95\'lll Engine Wiring Diagram-1 992-00 105, 140 JET BU<= BLACK BLU = BLUE BRN: BROWN GRY: GRAY GRN: GREEN PUR cPURPLE RED=REOTAN = TAN VlO =VIOLETWHT= WHITE YEL= YELLOW 1 -Stator 2.Tri99or 3 · Starter 4 • Wa 111g Modulo 5 •lclle Slabillzer 6 • Low Oil Sensor 7 -Rotational Sen$01' 8 • Enrichment Valve 9 • Temperaturo Gauge Sondet 1o-Engine Hamoss 11-SalUII'f12· 20 Amporo Fus& ·..· ..• > •• "\ g 11l. :t 10 'S=' 13· S atler Solenoid 14-Voltage Regulator 15· Water Tempen>tu z0mr­m0-i ::0 0)> r­(/) -< (/) -i ms:(/) . . ,.. , Power Trim Wiring Diagram with Solenoids./'/,..<", .,, ..._ 1 1I ' II I b '-I .), ' ' __ , ' ' , I ....o.. '-, '\. I oc ....f I I 5:.. r r e "" :.:! I I .... I I "' :: , I I f"' ,, ...:::.... -........................" .... .. r! .. \g a ·Stan Solenoid b •Tach . Connectorc • Key Switch Assembly d ·Trim Switch e •20 Ampere Fuse I · Trim Sender g • BottomCowl Swhch h • Pump and Motor i ••UP Solenoid j•• DOWN Solenoid 0519; W99 Power Trim Wiring Diagram with Relays a"-.. b................-...wn I ' , , I ,.•.li ' ', 0 ' ' ... 1,1 /" I! t/ m """" -.j,-fl ,,'-....... '-..j ,, .. a Tach. Connectorb • Key Switch Assembly c • Trim Switch d -Trim Sender e •Start Solenoid I ·To Sa.ttery g • To Alternatorh • Trim Pump and Motor I • • DOWN Solenoid j•• UP Solenoid k • Bottom Cowl Switch / I. • 20 Ampere Fuse m•Engine Hamess n • Remote Control Harness -I "'-... f "-... g :z: 0rnr-rn 0-I::0 -0):>r--<(/)-Irns:(/)c.n I(X)Ol19;WI.. c.o ..... . -.. , Engine Wiring Diagram-V250, V275 HP 15 Amp Stator BLK • BLACK BLU • BLUE BAN • BROWN GAY • GRAY GRN • GREEN PUR • PURPLE RED • RED TAN• TAN VIO • VIOLET WHT • WHITE VEL• YELLOW S!',.Al.. C6t9Svna Engine Wiring Diagram-V250, V275 HP 40 Amp Stator 051SSW1C c.n I c.c = G') z: .. 0 z: J> z: CJ m r­m 0 .. :rJ 0 J> ... (/) -< (/) .. m s: (/) IGNITION AND ELECTRICAL SYSTEMS Power Trim Wiring Diagram with Fuse Side Mount Control Wiring Diagram wtAES TO Et10t'fE 051!1:>W10 5-91 :· r 5-92 IGNITION AND ELECTRICAL SYSTEMS BLK = BLACK BLU= BLUE · · BAN = BROWN GRY= GRAY GRN : GREEN PUR = PURPLE RED = RED TAN =TAN VIO = VIOLET WHT= WHITE VEL= YELLOW 1 •Staner 2 •Ignition Stator 3 ·Flywheel 4 -Crank Position Sensor 5 •60 Ampere Alternator 6 •Low Oil Sensor 7 -Throttle Position Sensor 8 -Overheat Sensor 9 • Fuel Enrichment Valve 10· Termmal Block 11 ·20 Ampere Fuse 12· Cowl Trim Sw1tch Engine Wiring Diagram-1994 225 HP 13-To Trim Solenoids 14-To Remote Control Har11ess 15-E11gine Harness Plug 16-12 Volt Battery 17-Staner Solenoid 18· Electronic Control Module {ECM) 19-Shift Interrupt Switch 20-Starboard Ignition Modules •1.3.5 21-Pon Ignition Modules · 2.4.6 22· Ignition Stator 05195\Vlf I· Stator 2• Crank PoSition Sensor 3 •ThrottlePosition Sensor 4 • LOW Oil$witch S • 60 Ampere Alternator 6 • Temperatute Sensor 7 •Sta.er8-Sllln ln ertiJptSwitch9 • II Fuel lnjee or 10-#2 Fuel Injector 1t-lf3 Fuel InjeCor 12·#4 Fuel tnjector 13-115 Fuel ln]eCtOI 14·16 Fuel InjeCtor IS. Fuel Pump -.. 17· Oetonetion Module Hamoss(Not Us ed ) 18-Kr><>ek Sensor Hamess (Not Use<.) !? . '.. , Engine Wiring Diagram-1995 3.0L 225HP Carbureted / 3 2 .. , 4 7 ' + 20-CowiTrimSwitch ;= , 23-Starter Solenoid .. 26·AirTemperatureSensor . ....--E..!E . .. i 30-Ignition ECM ' ! 31· EFI (Fuel) ECM ! I 32· 16COM , 33-14 COM ' I · 1·'11 S4-#2COMBLI( = BIKk BLU • Blue BRN = Brown GRY • Gray GRN':; GrHn ORN e Orange PNK = Pink PUR = Purple RED = Red TAN a Tan WHT = Whlto VEL=-Yellow LT = Ligilt OAK:... Derk 2 I 33 ' :: I j-=­..--........... .=t,i 32 I .. ,,·H· L I' -1:1. L__ 30 ;;;:;;:; 28 . '-I ; w . , I ,--1i...._; 27 • .. "!&f 1 <=tf ··. ,j 4-26 1 ..2 'II ..; ,---..]J /9 i -.. / 10 ]IJ Ill,I,.i 14 17+ 16+.. 18 .. Ci) z-f 0z:l> zCJ mr­m0-f ::::0 0:l>(/) -< (/) -f m .. (/) c.n I 05t9SW!G C,0 w =er ;;2::r Ill.' ktVI'n. -w 22 \i -M.llftU . ' ..··. Engine Wiring Diagram-1995 225 HP EFI / 3 $> • 19 .. .. 4 .. . '[.1--' I..I . /7 / ' " 1 • Sta tor 2 • Crank Position Sensor 3 -ThrotUe Posltlon Sensor4 •Low Oil Switch(225 Cart) Only) 5 • 60 Ampere Alternator 6 -Temperature Sensor 7 ·Starter 8 • Shift Interrupt Switch 9• Fuel Enrichment Valve 1(). Starter Solenoid 11· UP Trim Solenoid 12· DOWN Trim Solenoid 1Cowl Trim Switch 14-Trim Motor 15-20 Ampere Fuse 16· #1 Capacitor Discharge Module 17·#3 Capae"or Discharge Module 18· .. Capac"or Discharge Module 19-Electronic Control Module20-12 Capacitor Discharge Module 21·#4 Capacitor Discharge Module 22·#6 Capacitor Discharge Modulo BLK e Bleck BLU =Blue BAN : lkown GI\Y • GrayGRN = Gr"" ORN a OrangePNK = Pink PUR s Pu..o REO = Red TAN =Ton WHT = White YEL = Yellow LT = LightOAK • Oork 05t95WIH CJ1 I CD .a:. G) :z -4 0 :z )> :z 0 m r­m ("")-4::::0 ("") )> r-(/) -< (/) -4 ms:: (/) ,.... . 0' .,, Engine Wiring Diagram-1 996-97 3oOL 225 HP Carbureted ij '· t t21 20 18 H !! 17 8 / 9 10 1 ° Stator 2 oCrank Position Sensor 3 -Throttle Position Sensor 4 ° Low Oil Switch (225 Carb Only) 5 ·60 Ampere Alternator 6 -Ground 7 ° Temperature Sensor 8 -Starter 9 -Shift Interrupt Switch 10-Fuel Enrichment Valve 11-Starter Solenoid 12· UP Trim Solenoid 13· DOWN Trim Solenoid 14· Ground 15° Cow! Trim SwitCh 16· Trim Motor 17· To 12 Volt Battery 18· Dlagnoslfc Harness 19-20 Ampere Fuse 2Qo Terminal Block 21· Ground 22· #S COM 23· #3COM 24· Grounds 25· #1 COM 26· lgnillon ECU 27·116COM 28-#4COM 29° #2COM 30-Grounds 31· "Ground BLK = Slack BLU = Blue BAN ..llrown GAY = Gn.y GRN = Green ORN = O ren gePNK •PinkPUR = Purple RED = Red TAN = Tan WHT = WnlteVEL .. Yellow LT .. LightOAK =Dark 05195WIJ G) z: .. 0 z: )> z: 0 rn r­rn 0 .. ::0 0 )> r­(/) -< (/) .. rn s: (/) CJ1 c.o CJ1 1 • 51a tor 2 • Cra nk Position Sensor 3..Th rott le Position Sensor 4 •Low 011 Switch 5 · 60 Ampere Atternator 6.. Temperature Sensor 7 -Starutr8 • Shift I nt errup t Switch 9 • #1 Fuoil..ector 10.112 Fuel lnjoctor 11·/13 Fuel Injector 12-114 Fuel injector 13-#5 Fuel Inje tor 14·16 Fuol lnjector 1$-Fuel Pump 16-Map Sensor 17·water Sensor 18· Air Temperature Sensor 19-To Remote Trim SwitchCowl Trim Swich 21· Remote Cont!OI Harness 22·DOWN Trim Solenoid 23-UP Trim Solonoid 24· St!rter Solenoid 20Am p ere F\JSO 29· Terminal Block 30-#5COM 31·#3COM 32·#1 COM 34· EFI (Fuel) ECM lgnHion ECM 36-16COM 37· #4COM 38-#2 COM Bll< : Sleek BLU : Blue BAN = Brown GRY .. Grey GRN = Green ORN • OrengePNI< z Pink PUR : Purple RED : Red TAN a: Ten WHT : While VEL = Yellow LT = Light DRK r Dark ··' . ' .. , Engine Wiring Diagram-1996-97 225, 250 HP EFI 2 /3/ v ..... .... 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Fue11f\tct>:KI? 4 • Oirtalniecsot 11 5 •OlrK1 1r1;ec.or 12te10f.f'3 7 • Olre.. l'leoe.ot#4 8 • Oiroct lnjK1c»#5 t• Direct ltl,leetor1$ 10.011Pc;.p1t·MAPSttl$ot12·T.P.S.•t {IMet) t3-T.P.$. n (Olliff} . -' 24-A.CC . atld Ttm Pump 20An!p&1 Fll$6 l,.,;tJon. Coils el'ld o:I-P.o.rnp 20 Amc>01e. Fuse 2f. Futl.. 1'2 (Ovls.de S.pa.taklt) 17·Fue!f1umo,11 (lrc1dGVip:w..r11101) 2&-12VtAI &ahery .» 'Tb Rem01tCo.ntrol Trim Men 31-nemO'IeComdChKkEtlgne t.IQ:N 34WmrlnFwl'-'"" 35-0vet-He.a!'-"! 1'11 3&-t.owOtltJgl'll37· ltfnperature Gaug.. 36-Beet .. C011o1..Modt.A• 3t-Mart PtwtttRtWr 4Q. Tritn ()Q..m l:telay 41· Tllm Up Rofloy U·Cov.tMQuntKTrlrnStlt 54 -'.... Engine Wiring Diagram-2000 1 15, 135, 150 HP Optimax DFI ..• ) ' ' " I · , 11 ' '! ! 1 . . n ____,., ...__15 --.. ..-...... 38 11 I. }J .. ,_=..-22 Jf Jf Jf J1 / t Jf IIi ::::::W;ld-" 53 sz s1 so 49 -· ..-2 4 ' -45 -... ---.. ··-· ..'If: B.. 1718190519;W1M IU)co -(j) :z :z )> :z 0rnr-rn 0--f :::0-0(/)--frn..(/) __, , .. , J-,...... )·....M;)4 Ofta ..,. .,s.tbtaii\IICW4t ' . 0Acll¥c* 137•Dil.ct--#A 6•Dtlte!..IS t ·DlftCI.,...,._II to-011,-,llf"IP tt•IAP.s.tlt::w..I· MAPS.r.t0t ., . ...,..,.,..s.IMWH't&.S-.S..=t'! ,.._,...,..o.s..,..'20-o.w-,.._, ru.o.ratw•.tlf 2t•..hMot » · ,... ... ..s..,., , .J-IOA.... ZC· ..Plofl'l'9O!:ul10 ..·.liM2S.lgn.II:JD ec. .... o......_ 20 M'IOI.!W Fv,.ft.. Sltlb"'''Citut20......,.,fli!M..1· Fl;.lf"/Air I..C.C.lOArpefe F"\IM;:=-:;.c;:::JOMIC*»ti\'OiliAII .. Y :J"·..Sclltt\Ooa'»-..•Ciau;e»o,_CIUoN,..o,., .....l911)S. W.. ... FiiMi Uplt ·..e.-S7 ·....r" ..COIII'Icttot 38-5..»To..T,.....,. dD-Co-. 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BUt : I!IIICIIBlU • 81111BRN •B•ow;nGAY • CrtyGNt. c'"" GlUt. o..n ..,. • h\tl ..... .......R£0 so t1WGl.tJt • T-.: WHT •\TI'IiikYEt a,.....,Lt. •U,.OK. •O.lo 52 Engine Wiring Diagrarn-1997 200 HP DFI ... 18 19I I 20 z __, -2 1 Qz :l> z CJ rn Irn 0 __, 0 :l> I -<(/) 0$1i51'11N rns:(/) c;n U) U) ll• M.a.PSena.ot l2-TP.$. 11(1f"'W) 1S.T.P.S.i2(011ttl') 14•CIW\Il Positi'on S.nsor 15-#olr T.m!*tturcSeas01 t..W....rSen;or 17•Shlft$;o.Mel'l ,8--Low-Ql Swileh 1t-aC)1illder Htod TtmperatureS..{Sta.rd Side) ,,. b •C)flnderHeedTtl'll9t r.a!Ufe S'MIICI't (Pon ..) 20·Di.I..Terrnina1Ct>llnlc1or 30-TORtmoM ConWITrim S\OIIteh 31·A..C-16= 38"' .-.=-::: -"?<> ' •1;i; 1 : 313r2. . 45 1 I "'44 EJ 115195W1P c.n I....&. = = Ci) :z --i 0 :z :l> :z 0 rn r­rn 0 --i :::0 0 :l>r-C/) -< (/) --i rn s: (/) 1 •Oiteet lnteelor II 2 •Ditect l....,,or n 3 •o..ct,,...or'-! • ·Ditta .."' •Olract .,.,..., 45 •Olrecllnjector f6 7 ·Oil Pump 8 •M pSene,or 9 •moctc Press\.lre-Sen or 1o •Smancran Gauge Homesa 11 •ThtodlePasotion Sensor (TPS) 12 ·CrnkPasWonSM&or13 · Low Oil S""ICII 14 •Shln Swoldl 15 -Air Temperature Sensor 11 •Wat•r Sensor 17 •&..bowel Head Temp-lUre Swikn 18·ilog:laiiJoal;irlo$llC Terminal Conneaor1S •eor.-Temper ture Sw•ldl : .. , Engine Wiring Diagram-2000 200, 225 HP Analog DFI 0®®0®® ® ..,......,,. Q) ® ® @ .. .. ""fr ooq:f ...'HI arttf!.. ... 4¥.' .. d ..! li ...... u.. 11 II ii :.! i c •J •! .. · ··· -·· i @ en ,..toIW '" •••...-.. @ <» tu a [iJ::: ===-11m .,. ,. 21 · Stalte r •.....-.l'!L \n'tl_......,.._ l•tDztll•t•JtfJ1 1U•1 '711-•JJt .. 14 20 • Port HOtel Temperature Switch 23 •60AmpereAitemaiOr ..r,o,....,. , • • @ t!.f'-'t • 4 CS... 2" •SttrterSOlenoid n• : : "". '""" 25 ·Nain: PowtrAeJay , ........_ : 26 -ECM 0<\vtr!Oil PumpCi,..., :ZOAml*t F\l5a @ F .. """..o$1:> 28 t ..... @ 30 •Acc8SS 0ty fJowef .... Cn 31 -Cllacl< Eng ine Ught :=: 32 -low 0.1Ug1!1 ' .... . 33 -w..,-an F"'el Light *-0 , . _,. 34 •0\.ier..HealUghl II 'f'fNII 35 . ToTempemuroGaugo R '' emoloCof>Ual 37 ·fue1Pumpl2(0ulsld&Vopo z0mIm0 .. ::0 0)> I(/)-<(/).. m .. (/) c.n I......=...... '{ 5-102 IGNITION AND ELECTRICAL SYSTEMS t1:Cl3·coa..lrlNN00N000I..bOco. ..,0 @$v .. !.......i..:bl)1=1·r:;..11)·...... OIL INJECTION SYSTEM 6-2 DESCRIPTION AND OPERATION 6-2 MERCURY OIL INJECTION 6-2 OPTIMAX OIL INJECTION 6-2 TROUBLESHOOTING THE OIL INJECTION SYSTEM 6-3 BLEEDING THE OIL INJECTION SYSTEM 6-3 PROCEDURE 6-3 OIL TANK 6-4 REMOVAL & INSTALLATION 6-4 CLEANING & INSPECTION 6-6 OIL PUMP 6-6 REMOVAL & INSTALLATION 6-6 OIL LINES 6-7 OIL LINE CAUTIONS 6-7 OIL PUMP DISCHARGE RATE 6-7 TESTING 6-7 .. OIL PUMP CONTROL ROD 6-7 ADJUSTMENT 6-7 COOLING SYSTEM 6·8 DESCRIPTION AND OPERATION 6-8 OPTIMAX 6-8 TROUBLESHOOTING THE COOLING SYSTEM 6-9 WATER PUMP 6-9 REMOVAL & INSTALLATION 6-9 CLEANING & INSPECTION 6-20 THERMOSTAT 6-20 REMOVAL & INSTALLATION 6-20 CLEANING & INSPECTION 6-22 TESTING 6-22 WARNING SYSTEMS 6-22 DESCRIPTION AND OPERATION 6-22 OIL QUANTITY INDICATOR 6-22 OVERHEAT TEMPERATURE WARNING 6-23 TROUBLESHOOTING THE WARNING SYSTEMS 6-24 WATER TEMPERATURE SENSOR 6-24 REMOVAL & INSTALLATION 6-24 TESTING 6-26 OIL GAUGE 6-26 TESTING 6-26 OIL LEVEL SWITCH 6-26 TESTING 6-26 REMOVAL & INSTALLATION 6-26 OPTIMAX WARNING SYSTEMS 6·27 DESCRIPTION AND OPERATION 6-27 1998-99 MODEL YEARS 6-27 GUARDIAN PROTECTION SYSTEM 2000 6-27 TROUBLESHOOTING THE WARNING SYSTEMS 6-28 SPECIFICATIONS CHART OIL PUMP DISCHARGE RATE 6-7 6-2 LUBRICATION AND COOLING Oil INJECTION SYSTEM Description and Operation Over the years, manufacturers have tried various ways of mixing oil with the fuel on £-stroke outboard engines. This was not only to make refueling easier, but to also provide more accurate fuel/oil ratios over the entire engine operational range. An outboard's requirement for a fuel/oil mix does not stay constant. Mixture requirement varies depending on engine RPM and load. A mixture that is too rich in oil results in excess exhaust smoke. Pre-mixing the engine lubrication oil with gasoline before use is by far the simplest method. Unfortunately, it's also the messiest and the greatest polluter of the environment. Nothing complicated here, just add the correct amount of oil to a certain volume of fuel in your tank, and the job is done. One important consideration often overlooked is the grade of 2-stroke oil used. Current standards call lor TCW-3, but check with your manufacturer for their recommendation. TCW-3 has a far superior additives that reduce many common outboardengine problems such as sticking rings and carbon build-up in the combustion chamber. It's also important to know what ratio of fuel tooil your engine manufacturer recommends. In reoent years, many manufacturers have reduced the ratio from 50:1 to 100:1. This means 100.parts of gasoline to 1 part of oil or half as much oil as before. The order in which you do things counts, too. Remember to put the correct amount of oil in the tank before adding the gasoline. so the gasoline will mix with the new oil as you fill the tank. The second popular type ot lubrication for 2-strokes is a mechanical oil pump sys­tems. Most outboard manufacturers use a mechanically driven oil pump mounted on the engine block. The oil pump is connected to the throhle by way of a linkage arm. The theory of operation here is that the crankshaft drives a gear in the pump, creating oil pressure. As the throttle lever is advanced to increase engine speed, the linkage arm also moves, opening a valve that allows more oil to flow into the oil pump. There are two schools of thought on the matter of where to inject the oil and this is where the significant dillerenoe lies between the mechanical oil-pump systems. Some manufacturers inject the oil into a port in the carburetor-intake system behind the carburetor throhle plate. This means !hal only pure fuel passes through the carburetor. The oil blends with the incoming fuel/air mixture immediately after it !eaves the carburetor throat. just before the mix enters the crankcase through the reed-valve plates. Other manufacturers inject the oil from the mechanical pump into a port in the engine mounted fuel pump, v.tlere it ismixed with the fuel before it enters the carburetor. All outboard engines since the late 60's are equipped with a system that's designed to recycle excess oil aocumulating in the crankcase. Oil that's injected into the engine is not completely consumed as it enters the combustion chamber with the air/fuel mix. This oil puddles inside the crankcase. To remove this excess oil, manufacturers have devised a simple system of small fittings screwed directly into the side of the powerhead block assembly at key points. These fittings have hoses connected to the car buretor intake system, so the excess oil from the crankcase can be mixed with the incoming air/fuel mixture. MERCURY OIL INJECTION The constant ration oil injection pump on the 40-60hp models is driven by a gear on the crankshaft and delivers a constant 50:1 fuel/oil mixture to each cylinder. The pump injects oil into the fuel stream ahead of the fuel pump. A 2-psi (13.8 kPa) check valve is installed in the fuel line between the fuel line connector and the oil pump discharge line. The check valve is used to prevent gasoline from entering the pump discharge line. The variable ratio oil pump on the 4D-275hp models is mounted on the powerhead and is driven by a gear and shalt arrangement off the crankshaft. Therefore, as soon as the crankshaft begins lo rotate, even during the cranking process, the pump also rotates and begins to deliver oil to lhe fuel/oil mixer. The pump will meter the injection oil for a fuel/oil ratio of approximately 50:1 at wide open throttle, with the mixture ratio changing to 100:1 at idle speed. OPTIMAX OIL INJECTION t See Figures 1 and 2 Oil in this engine is not mixed with the fuel before entering the combustion chamber. Oil is stored inside the remote oil tank in the boat Crankcase pressure forces the oil from the remote oil into the engine mounted oil reservoir. The engine oil reservoir leeds oil tothe oil pump. The oil pump is ECM driven and controls the oil distribution to the crankcase and air compressor. The oil pump has seven oil discharge ports. Six ol lhe oil discharge ports inject oil into the crankcase through hoses, with one hose foreach cylinder. The last oil discharge port sends oil to the air compres1 -Remote Oil Tank 2-Engine Oi Tank 3·on S<.w.y Hose to ""' Oi P\Jmp •·011 Pt.rnp 5·Oil Supply HoGes lOthe Cylinde!S (6) 6-011 Supply -to the I>Jr Compressor7-Air Compressor 8•Cheek valve 11 -Magnetic Float 12 -Air Pressure 13 •CrankCase Pressure w!CJn& Way Check Valve 0519!G33 Fig. 1 Oil injection system schematic-115 to 150hp 1 ... Air ComprcsSOf 2 •Engine Oil Reset\loir 3 ·Inlet Fitting 4 -Oil Aetum C..eck Valve $ -Oil Inlet Cooru!Ctioo 6 ·Crankcase Pressure line Connector7 -C..eckValves 8 -Oil Pump 9 -FHter 1Xi196G34 Fig. 2 Oil injection system schematlc-200 to 225hp sor for lubrication. Unused oil from the air compressor returns to the plenum and is ingested through the crankcase. The ECM is programmed lo automatically increase the oil supply to the engine during the initial engine break-in period. The oil ratio is doubled during the first 120 minutes of operation whenever the engine speed exceeds 2500 rpm and is under load; b..low 2500 rpm the oil pump provides oil al lhe normal ratio. After the engine break-in period, the oil ratio will return to normal: 30D-400:1 al idleand 60:1 at wide open throttle (depending on throttle load). ,..on some light boat applications after break-in is completed and the engine is being run at cruising speed (between 4000-5000 rpm) the fuel to oil ratio may be as high as 40:1 . This results lrom a reduced throttle opening with a corresponding reduction in fuel consumption. The oil pump on the OptiMax models is electrically operated by the ECM and controls oil distribution to the crankcase and air compressor. The oil pump has seven discharge ports. Six of the discharge ports inject oil into the crankcase through hoses, one hose for each cylinder. The fast discharge port discharges oil to the air compressor for lubrication. Troubleshooting the Oil Injection System Like other systems on i-2-stroke engine. the oil injection system emphasizes simplicity. On pre-mix engines. when enough oil accumulated in the crankcase it passed into the combustion chamber where it burned along with the fuel. Since oil is a fuel just like gasoline. it bums as well. Unlike gasoline, oil doesn't burn as elficienlly and may produce blue smoke that is seen coming out of the exhaust If lhe engine was cold, such as during initial start-up, oil has an even harder lime igniting resulting in excessive amounts of smoke. Other problems. such oil remaining in the combustion chamber, tend to foul spark plugs and cause the engine to misfire at idle. Most of these problems have been alleviated by the introduction ol automatic oil injection systems. ,..One of the most common problems with oil injection systems is the use of poor quality injection oil. Poor quality oil tends to gel in the system, clogging fines and filters. It is normal for a 2-stroke engine to emit some blue smoke from the exhaust. The blue color or the smoke comes from the burning 2-stroke oil. An excessive amount of blue smoke indicates too much oil being injected into the engine. On most engines, this is usually caused by an incorrectly adjusted injection control rod. If the exhaust smoke is white, this is a sign of water entering the combustion chamber. Water may enter as condensation or more seriously may enter through a defective head gasket or cracked head. Usually white smoke lrom condensation will disappear quickly as the engine warms. If the exhaust smoke is black. this is a sign of an excessively rich fuel mixture or incorrect spark plugs. The black color of the smoke comes from the fuel burning. Bleeding the Oil Injection System PROCEDURE • See Figures 3 and 4 30-275 HP OIL PUMP INLET HOSE 1. With the engine shut off, hold an absorbent cloth below the oil injection pump and be prepared to catch the oil as it oozes from the bleed screw. 2. Loosen the bleed screw three, maybe lour full turns, and allow the air trapped in the system to exit the inlet hose. ,..This procedure also allows the oil pump to fill with oil. 3. When a steady stream of oil is observed with no sign of air. lighten the bleed screw securely. OIL PUMP OUTLET HOSE 1. On all engines except the V-6 models, purge air from the outlet hose by running the engine (on a 50:1 fuel/oil mixture) at idle speed until no more air bubbles are present in lhe outlet hose. 2. On V-6 models, if any air bubbles persist, they can be purged out of the hose by removing the link rod and rotating the pump arm full clockwise while operating the engine at 1 OOD-1500 rpm. LUBRICATION AND COOLING 6-3 l· Bleed Sctew 2-lnlet Hose3-Outlet HOSil OS191i001 Fig. 3 Typical oil pump assembly including the bleed screw and hose locations 4· Pump a.rm OS196G02 Fig. 4 Typical V-6 powerhead oil pump assembly including the bleed screw and link rod locations 3. If necessary, gently pinch the fuel line between the remote fuel line connector and the oil injeclion pump T' filling. This will cause the fuel pump to provide a partial vacuum which will aid in the removal of any trapped air in lhe system. 4. Afterthis procedure. reinstall the link rod. OptiMax ,..If a new powerhead is being installed or the oil hoses or pump have been removed, It Is recommended that all air be purged from the oil pump and hoses. This can be accomplished by using a gearcase leakage tester (FT-8950). Connect the leakage tester to the inlet t-liHing on the onboanl oil reservoir. While clamping off the Inlet hose, manually pressurize the reservoir to 10 psi. Using the DDT, activate the oil pump prime sequence. Maintain the 10 psi pressure throughout the auto prime sequence. when the auto prime is completed, remove the leakage tester and refill the onboard oil reservoir. Priming the oil pump (filling the pump and hoses) is required on new or rebuill engines and any time maintenance is performed on the oiling system. There are three methods for priming the oil pump: SHIFT SWITCH ACTIVATION PRIME This method does three things: .. Fills the oil pump, oil supply hose feeding pump and oil hoses going to the crankcase and air compressor .. Activates the break-In oil ratio .. Initiates a new 120 minute engine break-in cycle DIGITAL DIAGNOSTIC TERMINAL (DDT)-RESET BREAK-IN This method is the same as the above method, except the run history and tauII history are erased from the ECM. DIGITAL DIAGNOSTIC TERMINAL (DDT)-OIL PUMP PRIME This method fills the oil pump, oil supply hose feeding lhe pump and the oil hoses going to the crankcase and air compressor. ' '· 6-4 LUBRICATION AND COOLING Use the DOT to activate the Auto Prime function. The oil pump should discharge 3.44-3.99 ounces (102-118 ml) during the auto prime period. 1. To check the oil pump output: • Verify the on board oil reservoir is full • Release any pressure (loosen cap) from the remote oil tank in the boat • With the engine running,use the DOT to activate the Auto Prime • Using a graduated container, record the amount of oil discharged• Retighten the cap on the remote oil lank Oil Tank REMOVAL & INSTALLATION ** WARNING Proper oil line routing and connections are essential for correct oil injection system operation. The line connections to the powerhead and oil pump look the same but may contain check valves of differing calibrations. Oil lines must be installed between the pump and powerhead corre..tfy and connected to the proper fittings on the intake manifold in order for the system to operate properly. 38-60 HP t See Figures 5, 6 and 7 1. Disconnect the battery cables at the battery. 2. Remove the engine cowling. 3. Remove the starter/oil tank bracket (if necessary). 4. Disconnect the oil hose and low oil sensor wires at the bullet connectors. 5. Remove the low oil sensor from the oil lank. ** CAUTION The sensor is fragile. Always handle it with care. 6. Remove the oil tank assembly from the powerhead. To install: 7. Install the oil sensor into the lank and lighten the screw securely. 8. Connect the oil level sensor wires at the bullet connectors. 9. Connect the oil line to the pump. 1-Screw2-Oil Level Sensor Fig. 5 Exploded view illustration of the 3D-40hp oil tank assembly . • . a>196G03 ..-2 1.0iltank 2. Cap assy. 4. Pushnut6. Vent B. Grommet9. Boot 0-5 10 10.Boot ..11. Switch 13. Washer 14. Hose Fig. 6 . . . and the 55-60hp engine mounted oil tank :;::;: WARNING 11 «.196001 Any time the oil tank hose is disconnected, the oil injection pump must be purged (bled) of any trapped air. Failure to bleed the system could lead to powerhead seizure due to lack of adequate lubrication. 10. Install the oil tank onto the powerhead. 11. Tighten the oil tank retaining bolls securely tothe powerhead 12. Install the engine cowling. 13. Connect the battery cables. 75-125 HP t See Figure 7 1. Disconnect the battery cables. 2. Remove the engine cowling. 3. Disconnect the oil reservoir outlet hose from the fitting and let the reservoir drain into a suitable container. 4. Disconnect the low oil level sensor at the bullet connectors. These connectors are located at the bottom of the oil reservoir. 5. Remove the starter motor upper bracket and remove the oil reservoir screws from the bracket. 6. Remove the lower screws securing the oil reservoir and remove the reservoir from the powerhead. '{ ,•. To Install: 7. Install the oil reservoir onto the powerhead and align !he mounting holes. 8. Secure the oil reservoir with the mounting screws. 9. Coooect the low oil level sensor wires al the bullet connectors.10: Connect the oil reseswir outlet hose. :;:::: WARNING Any time the oil tank hose is disconnected, the oil injection pump must be purged (bled) of any trapped air. Failure to bleed the system could lead to powerhead seizure due t.o lack of adequate lubrication. 11. Refill the oil reservoir. Do not over fill the reservoir. Add only enough oil to bring the oil level up lo the bottom of the filler neck. ,..The oil tank capacity for 3·cyllnder models is 3.2 quarts (3.0 liters) and 4-cyllnder models Is 5.13 quarts (4.9 liters) 135-275 HP ENGINE MOUNTED OIL RESERVOIR • See Figures 8 and 9 1. Disconnect the reservoir oil hoses at the oil pump. II the reservoir still has some oil in 11, plug the hoses to prevent oil from leaking oul 2. Disconnect the tow oil level sensor wires or remove the fill cap with the wires still attached. 3. Remove the three bolts securing the oil reservoir to the powerhead and then remove the oil reservoir. LUBRICATION AND COOLING 6-5 To Install: 4. Apply a threadlocking compound, such as loctile • 222, or equivalent, to the threads or the mounung bolts and then secure the on reservoirto the powerhead. TIQhten the bolls to 25 inch lbs. (2.8 Nm) onthe 135-200hp models or 150 inch lbs. (16.9 Nm) on the 250 and 275hp models. 5. Install the input hose to thelop of the oil reservoir and secure it with a tie-wrap. :;::;: WARNING Any time the oil tank hose Is disconnected, the oil injection pump must be purged (bled) of any trapped ajr. Failure to bleed the sys· tem could lead to powerhead seizure due to lack of adequate lubrl· calion. 6. Connectthe oil level sensor leads to the bullet connectors or install the filler cap. 7. Fill the reservoir tank.Be careful to not overfill the tank. REMOTE OIL TANK • See Figures 9, 10 and 11 The remote oil tank should be installed inan area in the boat where there Is access lor reli fling the tank. The lank should be restrained to keep II from moving around. causing possible damage. An acceptable means ol restraining the tank would be the use ol eye bolls and an elastic restraining strap across lhe center or the tank. Taking care that any metal hooks do not puncture the lank. Keep In mind, when lnslaJIIng the lank in tight areas. that this lank will be under pressure while lhe engine is operating and will expand slightly. Therefore. the restraints used with the tank should be left Wllh a small amount of slack lo enable the tank expand. 036!141'65 Fig. 7 The tank Is provided with an oil level indicator which is visible through a window In the cowling a3/3>1PC9 Fig.8 Atypical oil reservoir installation Fig. 9Remote oil tank for the oil injection system ready for installation In the stern of the boat on top of the powerhead providing gravity flow to the oil pump 05196606 Fig. 10 Adding oil to a typical remote oil tank installation in the stern of a boat under a seat against the transom Fig. 11 Two different types of oil injection hose connections, the quick-disconnect type and one-piece type 6-6 LUBRICATION AND COOLING Oil hosesrouted through the engine well must be able to reach the hose fittings on the enginethrough itstunrange of movement and not bind. stretch or kink. Any lose of injector oil could cause serious damage to the powerhead. CLEANING & INSPECTION One of the most common problems with oil injection systems is the use of poor quality injection oil. This poor quality oil tends to gel in the system, clogging oil lines and fillers. If this is found to be the case with your system, or ifthe powerhead has been sitting in storagetor a length of time, it is wise to remove the oil tank and clean it with solvent. While it is removed,takethe opportunity to inspect it tor damage and replace it as necessary.The oil tank is the only source of oil for the powerhead. If it should leak. the powerhead will eventually run out of Injection oil, with catastrophic and very costly results. Remember,thereare no parts stores when you are miles out at sea. Oil Pump REMOVAL & INSTALLATION :;::;: WARNING Proper oil line routing and connections are essential for correct oil injection system operation. The line connections to the powerhead and oil pump look the same but may contain check valves of differing calibrations. Oil lines must be installed between the pump and powerhead correctly and connected to the proper fittings on the intake manifold in order for the system to operate properly. The only purpose for disassembling oil injection pump is to locale a problem in oil delivery. For example, If the pump is frozen due to debris or rust, the pump can bedisassembled and cleaned. Constant ratio (46-60 HP) • See Figures 12, 13 and 14 1. Disconnect the oil inlet and dischargehose from the pump. 2. Remove the pump mounting screws. 3. Remove the pump assembly from the powerhead. ,..Ifthe pump d.riven gear remains in the engine block,use a pair of needle nose pliers to remove it. 4. Remove the 0-rings and inspect them forcuts, pinching or any damage. To install: 5. Throughlylubricatethe driven geaTshaft with needle bearing assembly lube. 6. Insert the driven gear into the bearing assembly. Make sure that the gear is properly engaged on the pump shaft. 7. Coat the 0-rings with needle bearing assembly lube and install them onto the pump assembly. 8. Install the pump assembly into the powerhead. Apply a threadlocking compound, such as Loctile• 271, or equivalent, to the threads of the pump mounting screws. Install the screws and tighten to45 inch lbs .. (5.1 Nm). 9. Connectthe oil inlet and discharge hoses to the pump and clamp them securely to the pump using new lie-wraps. Variable Ratio (46-275 HP) • See accompanying illustrations 1. Pry theoil injection link rodfree of the ball joint on the injection pump lever. Takecare not to alter thelength of this rod. 2. Position a suitable container as far as possible under the oil pump to receive oil drained from the tank 3. Snip the Sta-strap at the inlet lilting. Squeeze theoil supply line fromthe tankto the pump, to restrict the now of oil while pulling it free of the lilting. 4. Allow the contents of the tank to drain into the container. 5. Pun the oil line free ofthe other oil pumpfitting. 6. Removethe two bolls securing the pump to the powerhead and lilt the pump clear. ' '· 0519000 05196606 05196G09 Fig. 12 Oil pump location on the powerhead Fig. 13 Side view of the ratio oil pump Fig. 14 The oil pump isdriven off the crankshaft 03134PD1 Step 1 Step 2 Step 6 Step 7 To install: 7. Check to be sure the shaft of the oil pump will index into the slot at the center of the crankshaft driven shaft. If the two are no longer aligned, rotate the pump shall to match the slot in lhe driven shall Install the oil pump with the pump shall indexed into the slot on the driven shalt Secure the pump to the powerhead with the two attaching bolts. Tighten the bofls securely. 8. Connect the line from the tank to the lower pump fitting. Connect the line from the fuel pump to the upper pump fitting. 9. Snap the oil injection link rod back onto the ball joint on the pump lever. 10. Adjust the return spring tension on the lever shaft to permit the correct amount of friction for the lever to stay in place when the rod is moved. 11. Fill and bleed the oil injection system. OptiMax • See Figure 15 The manufacturer has made no provisions for rebuilding this pump. Spare parts are not available. II any part is found to be defective and no longer fit for service the pump must be replaced. Save the 0-rings, even if they are defective. The old ring will be essential when purchasing a new ring to ensure the proper type and size ls obtained. 1. Disconnect the wiring harness from the pump. 2. Mark the hoses for correct location and disconnect the oil hoses. 3. Remove the bolls securing the pump to the powerhead and remove the pump assembly. To install: 4. Install the pump assembly onto the powerhead tighten the bolls. 5. Reconnect the oil hoses in the correct locations. 6. Connect the wiring harness. 7. Refill the oil system. Refer to the oil pump priming procedures to prime the oil pump. Oil lines OIL LINE CAUTIONS • Do not bend ortwistthe oil lines when installing. • When installing clips, posilion the tabstoward the inside and make sure they are not in contact with other parts. LUBRICATION AND COOLING 6-7 1·C<>Il 2•Piston Assembly S•01DischargePo.. (4 shcwm) 6•7 Inlet Check Valva · Plunger Fig. 15 Electrically operated OptiMax oil injection pump assembly • Check the oll lines, when installed in position, do not come in contact with rods and levers during engine operation. • Secure all valves and sensors using their original fasteners. • lnstafl hose protectors in their original posilions. • Extreme caution should be taken not to scratch or damage oil Jines. • Do not excessively compress an oil line when installing clamps. • Always use lactory type clamps when installing fuel lines. Never use screw type clamps. • When installing the oil tank, ensure oil lines will not be pinched between the tank and the powerhead Oil Pump Discharge Rate TESTING 1. Connect a remote luel source to the powerhead with a 50:1 oil and luel pre-mix. 2. Install a flush device to the lower unit or place the outboard in a lest tank. 3. Remove the cowling and disconnect the oil pump output line (clear hose) !rom the fuel line "Tee" lilting. Plug the fuel line to prevent any luel leakage while the outboard is operating. 4. Disconnect the !ink rod from the oil pump lever. Set the oil pump lever as indicated in the flow specifications below. 5. Place Ihe oil pump output hose into a graduated container, 0 to 25Dcc or equivalent. Start the powerhead and operate it at the rpm and for the length of lime speciiied. li the oil injection pump output is less than specified, the pump will need to be replaced. O'I P o· hISC ar R t aeModel Min. Flow Max Flow 15min 1 -175 HP 2 5HP 3min tl>196CC1 Oil Pump Control Rod ADJUSTMENT See the "Maintenance and Tune-Up" section for oil pump linkage adjustment. 6-8 LUBRICATION AND COOLING COOLING SYSTEM Description and Operation Water cooling is the most popular method in use to cool outboard powerheads. A ·raw-water" type Pump delivers seawaer to the powerhead, circulating it through the .tcylinder head(s). the thermostat, the exhaust housing, and back down through the outboard. The water runs down the exhaust cavity and away, either through an exhaust tube or through the propeller hub. Routine maintenance of the cooling system is quite important, as expensive damage can occur if it overheats. The cooling system is so important, that many outboards covered in this manual Incorporate overheat alarm systems and speed limiters, in case the engine's operating temperature exceeds predetermined limits. Poor operating habits can play havoc with the cooling system. For instance, run ..ing the engine with the water pickup out of water can destroy the water pump Impeller In a matter of seconds. Running in shallow water, kicking up debris that is drawn through the pump, can not only damage the pump itself, but send the debris throughout the entire system, causing water restrictions that create overheating. The water pumps used on most outboards are a displacement type water pump. Water pressure is increased by the change in volume between the impeller and the pump case. .. On most outboards, the water pump is mounted on top of the tower unit. A driveshaft key engages a flat on the driveshaft and a notch in the impeller hub. As the driveshaft rotates. the impetrer rotates with it. A thermostat is used to control the flow of engine water, to provide last engine warm-up and to regulate water temperatures. An element in the thermostat expands when heated and contracts when cooled. The element is connected through a piston to a valve. When the element is heated. pressure is exerted against a rubber diaphragm, which forces the valve to open. As the element is cooled, the contraction allows a spring to close the valve. Thus. the valve remains closed while the water Is cold, limiting circulation of water. . As the engine warms, the element expands and the thermostat valve opens, permitling water to flow through the powerhead. This opening and closing of the thermostat perm1ts enough water to enter the powerhead to keep the engine within operating limits. OPTIMAX • See Figures 16 and 17 Cooling water enters the cooling system through the lower unit water inlets. The water pump assembly forces water through the water tube and exhaust adapter plate passages filling the powerhead central water chamber (located behind the exhaust cavity). Water enters the exhaust cover cavity through 2 holes near the top of the exhaust cover On the 200-225hp models there are 6holes-3 on each side and 1 slot (top) that connect the central chamber to the exhaust cover cavity. Water exits the exhaust cover cavity through 4 slots (2 on each side) filling the water passages around the cylinders. Water flows around each bank of cylinders to the lop of the cylinder block. On the 200-225hp models, water flow is directed around each cylinder steeve by 6water dams. Water flow exiting the cylinder block is-controlled by the thermostats (1 in each cylinder head) and the poppet valve (on the 115-150hp models that is located at the bottom starboard side of the powerhead and on the 200-225hp models is located in the exhaust adapter plate). At tow rpm (below 1500 rpm). the thermostats control water flow depending upon engine temperature. When the thermostats are open, water passes through the cylinder heads and exits to the drive shaft housing. At higher rpm (above 1500 rpm), the poppet valve will control the water flow. On the 115-150hp models, water that passes through the poppet valve enters the water passages in the adapter plates. Water passes through the adapter plates into the driveshaft housing. On the 200-225hp models, water that passes through the poppet valve enters the water passages in the exhaust tube to help cool the exhaust tube Water will exit the exhaust tube through 2 slots at the top of the exhaust relief holes area (helping keep the holes clear of carbon and salt buildup) and through 2 holes at the lower rear of the exhaust tube into the driveshaft housing. Water dumped into the driveshalt housing bui Ids up a wall of water around the exhaust tube. This performs two functions: • It helps to silence the exhaust • Prevents air from being drawn into the water pump Water exits the engine in 3 locations: • On the 115-150hp models, excess water fromthe wall of water exitsaround anodes on the gear housing. On the 200-225hp models, the water exits through the bottom art area of the driveshalt housing • Water that passes through the air compressor exitsthrough the tell tale hole • On the 115-150hp models, water exits through two Vein. (3.175 mm) holes in the lower adapter plate into the exhaust. On the 200-225hp models, water exits through a strainer screen in the exhaust adapter plate into the exhaust tube mixing with the exhaust gases. To allow complete water passage filling and to prevent steam pockets, all of the cooling passages are interconnected. Small passages are incorporated to allow the cooling system to drain. Model Year2000 Water Flow Diagram Cylinder Block and Adaptor Plate \ • AIICotr.ptoHSOr Orfv• Shaft Housing 2•o,t'MOt..COYor....(JftOII\"""fa:.aJISlr.­ llci\ IY.III'I\IIfypa"olllttd<-»'111'19 3 •Th.lmCt'.ttt(2') 143'F (51,?'"C•-•INI.I<*.td..n;tnct .... ..:Mde 4• S:r•Mr:kc;«. ICt'·ii .!)OI'•ndblttail.,...tUrtl.lll¢1-l81rieled. ..•nor"'ii0¥6ftltatnlr. l.. ...boJ.aJ( s •Exi\IIWI.OMcltrA.)tt-...ot""*Mcri $·..1V.JM-Carttfc:tsw.ldltlftWMI'I..Rif"M NCI«.p!!pplll "ltt¥tit..opon.c!IIII'WAPM,..t.. ' '· ..tiCLtetel!PfOP«CipW.IMg ....UI'fl (Micdd'J•I¥1 warun..'lalld:t,1 • w.ttt OloCIOIItomA!tiCorn;ns.-..b llltl•blt..on -S ·PI:dFwlll*I-Ril!ICOOiototulirtloP'Orlfi.iti RJII. 9 · W..OI,t'npH.::es£ll"*-«..(2aJdl) IIBA{3.115 .M,I -llllol"'are..N,...rp..w.ernoll_,.,tJH4'19Coll'lior S*!P.n.l ........ lbo4Jmllll.. 10·Wi':.C iibo 1l·..k\ltfrtttt.lt....l\lsfl. 12·WA..1olWJ!a-11W-t....O..i.\cbl:, -..ot pumpruydta.wa".li!,....eng n.w1 0¥W!t1Htecl.n&. 1:)-EJ'c.s.t"'..._'" lrom.;aJ ClwaltlrlfO'I•ndeld'.lh15lbi.Jdlef .. , ... ..W..Itth:at.!eS.."UIIIlt 0519.. Fig. 16 OptiMax water flow diagram 115-150hp Model Year 2.000 Water Flow Diagram CyHnder Block and Adaptor Plate Fig. 17 OpliMax water tlow diagram 20G-225hp Troubleshooting the Cooling System • See Figure 18 Poor operating habits can play havoc with the cooling system. For instance, running the engine with the water pickup out of water can destroy the water pump impeller in a matter ot seconds. Running in shallow water. kicking up debris that is drawn through the pump, can not only damage the pump itself, but send the debris throughout the entire system, causing water restrictions that create overheating. Symptoms of overheating are numerous and include: • A "pinging·· noise coming from the engine, commonly known as detonation • Loss of power • A burning smell coming from the engine• Paint discoloration on the powerhead in the area of the spark plugs and cylinder heads .. It these symptoms occur, immediately seek and correct the cause. If u· the engine has overheated to the point where paint has discolored, it may be too late to save the powerhead. Powerheads in this state usually require at least partial overhaul. I So what are major causes of overheating? Well the most prevalent cause is lack of maintenance. Other causes which are directly atlributable to lack of maintenance or poor operating habits are: Fig. 18 A new water pump impeller (left), alongside an impeller unlit for further service. Lack of water will render an impeller useless in just a few seconds. LUBRICATION AND COOLING 1 •AtCocnptt$$0t 1 • 3 •TbeMk>S&ab (2) 1.. Cy..d&J Head C¢v6r-A..!rom tteild lor .!laUD· tion.normalfyp:wtdhtacJ..f(4i•C)-ifsu:td0$«1, engin!J MI91'(;1 0..9PC2 Step16 To install: 10. Position the water pump tlase on a press. Coat the outer diameter of the oil seals with Blue Loctite "· or equivalent. Use a suitable mandrel and press the smaller diameter of the oil seal into the pump base with the lip of the seal towards the impeller side. Use a suitable mandrel and press the larger diameter oil seal into the pump base with the lip of lhe seal towards the driveshalt bearing side. Clean any excess Loctite 8 from the oil seals. Install a new 0-ring into the groove in the driveshalt bearing side of the pump tlase. Lubricate the 0-ring and the oil seals with Multi-purpose Lubricant, or equivalent. 11. Remove the lower unit-to-water pump base gasket from the lower unit. Take care not to damage the gasket. Install this gasket over the water pump base 0-ring. 12. Install the pump tlase into the lower unit. Check to be sure the pump base is seated firmly against the lower unit. 13. Install the following items in the order given: The pump tlase-to-face plate gasket. the face plate, and then the face plate-to-pump cover gasket. The gaskets and the face plate are indexed by dowel pin location and MUST be installed properly. 14. Coat the impeller drive pin area of the driveshaft, the flat area on the shaft justabove the face plate, with Multi-purpose Lubricant. Position the impeller drive pin on the driveshaft. Slide a new impeller down over the driveshaft and drive pin. the lower unit is opened. Remove and save the impeller drive pin from the flat area of the driveshalt. 6. Lift upward on the face plate and remove it and the gasket from the mounting studs. Clean any gasket material from the face plate and from the pump base. 7. Remove the water pump base by first padding the surface around the pump base. 8. Using a pair of screwdrivers, pry upward and evenly on both ends of the water pump base. Once the water pump tlase is loose, slide the pump base up and r '· off the end of the driveshalt. 9. Remove the 0-ring and oil seals from the tlase plate assembly. II the oil seals are unfit for further service, the manufacturer recommends the pump base be replaced. The base is available in kit form and will include new seals. II the kit is not available, proceed to remove the seals as follows: remove lhe oil seals from the pump base by prying or driving them away from the impeller side of the pump base. Remove the 0-ring from the groove in the pump base. Clean any gasket materiai from the upper and lower surfaces of the pump base. ,..Use athin blade screwdriver and check to be sure the impeller drive pin has not moved partially oflthe flat on the driveshaft. If the drive pin movesoff the flat, the impeller would be forced against the pump insert afterinstallation and causepremature impeller wear. The drive pin should be free to moveupward approximately Y1s in.(1.59mm). 15. Obtaining good quality sealing products is well worth the extra cost to prolong satisfactory service of lhe lower unit. 16. Apply a thin coating of Multi-purpose Lubricant onto the inside diameter of the water pump cover. Slide the assembled water pump cover down over the driveshafl and water pump studs. Rotate the driveshaft clockwise and at the same lime push down on the pump cover to ease entry of the impeller into the cover. 17. Install the water pump cover retainer washers. nuts, and bolls. Tighten the boll and nuts evenly to the torque value as follows: • Nuts: Y.-28 30 inch lbs. (3. 4Nm) • Nuts: o/1s·24 40 inch lbs. (4.5Nm) • Boll:1/4·20 20 inch lbs. (2.3Nm) :r 0-ring 03.9PCS Step19 ,..DO NOT overtighten the bolt or nuts on plastic water pump covers. Overtightening could cause the cover to crack during operation. 18. Install the centrifugal slinger over the driveshaft and down against the pump cover. 19. For units equipped with a flush plug: Position the gaskel onto the flush plug, and then install the plug into the lower unit. LUBRICATION AND COOLING 6-17 50-200HP t See accompanying illustrations ,..A high volume pump is used on the 5D-200hp lower units. 1. High volume pumps can be easily identified by comparing their appearance to this exploded view illustration. 2. Slide lhe sealing ring from the top of the water pump. Remove the four bolts, Step1 Step2 6 'f-fI I * I QI I[j):I.. I I High volumewater pump O:ili09C02 6-18 LUBRICATION AND COOLING Step6 :r ' •. Step7 washers, and isolators securing the pump cover to the pump base. If necessary, use two screwdrivers, one on each side, and pry the pump up and free of the outer plate. Remove and discard the gasket. The water lube grommet, if still in serviceable condition may remain in place on the water pump cover. The impeller may remain on the driveshafl or may slick in the pump cover. 3. If the impeller remained on the driveshafl, slide the impeller up and free of the driveshaft. If the impeller is stubborn, it may be necessary to use a punch and hammer to drive the impeller upward and oil the driveshaft. II a punch and hammer will not move the impeller, the only answer is to use a chisel and split the impeller. A new impeller should always be installed when the lower unil is opened. Remove and save the impeller drive pin from theflat areaof the driveshalt. 4. lift the outer plate and gasket up and free ot the pump base. Clean all old gasket material from the plate and the pump base. 5. IIworking on a 50hp or 60hp model (since 1990),pry up the water pump base from thelop of the lower unit-refer to the exploded drawing. For all other models, Remove the bolts and washers securing the water pump base to the lower unit. 6. Usetwo screwdrivers and prythe water pump basefrom the lower unit. Remove and discard the gasket under the base. 7. Inspect the condition of the two oil seals housed in the water pump base. Check the oil seals for correct installation. On this type water pump, the seals must be installed back-to-back. One prevents Jubricanl from escaping the lower unit and the other prevents water from entering. Ifeither seal is no longer til for service, pry both seals out with a screwdriver, one at atime. To install: 8. II the two oil seals were not removed during disassembly, skip this step and proceed directly to the next step. II the two oil seals were removed during disassembly, proceed as follows: • Obtain Oil Sear Driver(C-91-13949).loctite 6 271,or equivalent, and Quicksilver Needle Bearing Assembly lubricant (C-92-42649A·1),or appropriate substitutes. • Apply Loclite "to the outer circumference and pack the lip of thetwo oil sealsto be installed with lubricant. Slide the first seal, with the seal lip facingawayfrom the tool, onto the longer shoulder side of the installation tool. SUpport the water pump base on in arbor press and press in the seal until theshoulder of the tool bottoms against the pump base. If working withoutthe special tool, carefully and squarely tap in the seal until the seal seats inside the base. 9. Slidethe second seal, with the sear lip facing toward the tool, onto the shorter shoulder side of the installation tool. Install this second seal in the same manner as the first. 10. Place anew gasket in place on the lower unit. Slide the water pump base downover the driveshafl. Tap the base down lightly to seat it over the gasket. Apply loctite"· or equivalent. to the threads of the six retaining bolts. Install and tighten the bolts and washers to atorque value of 60 inch lbs. (6.8Nm). 11. Slide the gasket and then the outer plate down the driveshaft. 12. Coat the impeller drive pin area of the driveshaftwith Water Resistant Multi· purpose lubricant. Position the impeller drive pin on the driveshaft. Slide anew impeller down the driveshaft to index over the drive pin. ,.If at all possible, always install anew water pump impeller. If the old Impeller must be installed, always install the impeller In the samepositionto allow the vanes to rotate In the samedirectionas the original installation. Installing the impeller in such amanner to causethe vanes to rotate in the opposite direction will only result in premature impeller failure. 13. Applyathincoating of water resistant multi-purpose lubricant to the inside diameter of lhe water pump cover. Apply loclite® 271or equivalent to lhe threads of • the four securing bolls. Slide the cover down the driveshafl. Rotate the shall clockwise and at the same lime push down on the pump cover to ease entry of the impeller into the cover. J / Step4 Outer pla!e Water base Step5 14. Install the water pump cover retaining bolls, washer, and isolators. Tighten the bolls to a torque valve of 60 inch lbs. (6.8Nm). 15. Slide the sealing ring down the driveshalt onto the top of the water pump cover. 16. Apply a coaling of water resistant multi-purpose lubricant around the inside diameter of the water tube grommet as an aid in later assembly to the water tube. 225-275 HP • See accompanying illustrations 1. Ufl out the water tube guide and seal from the pump cover. 2. Remove the four retaining bolts, washers and nylon bushings securing the pump cover to the lower unit. 3. Use two screwdrivers-one on each side-and pry the pump cover off the studs. If the cover is "frozen" to the pump. it may be necessary to tap on the cover, with a soft head mallet, to break it loose from the plate. 4. If the seal in the cover is dama_ged, or unfit for further service, the recommendation is to replace the pump cover. A kit is available from the local dealer and will include a new seal-installed. If the cover kit is not available, remove the seal using a hammer and punch. Drive the pump cover seal out of the cover. from the impeller side. Tap the new seal into place using a deep socket the same size as the seal. 5. Slide the impeller .. and free of the driveshafl. lf the impeller is stubborn, it may be necessary to use a punch and hammer to drive the impeller upward and off the shaft. If corrosion has developed on the driveshaft. use a piece 300 grit paper and remove the corrosion to make the task of removing the impeller much easier. ..In an extreme situation, it may be necessary to split the impeller with a chisel and hammer. Splitting the impeller is not really as bad as it sounds, because a new impeller should always be installed when the lower unit is opened. Be extra careful not to damage the driveshaft or key in the impeller. 6. After the impeller has been removed, lift out the impeller drive (WoodrufQ key from the driveshafl. Step 13 sealWaterpump body Oil0-ring 1 /seal....0 03739618 LUBRICATION AND COOLING 6-19 7. Lift up on the impeller plate and slide the plate free of the driveshaft. 8. Clean all gasket material from both sides of the plate. 9. Remove the seal carrier from the driveshaft by inserting two pump cover bolls partially into the seal carrier-one on each side. 10. Using a pair of screwdrivers under the heads of the bolts, pry the seal carrier up and out of the pocket in the housing. 11. Remove the seal and 0-ring from the carrier. To install: 12. If the two oil seals were not removed during disassembling, skip this step and proceed directly to the next step. If the two seals in the carrier for 225hp model or one seal in the carrier for the 275hp model were removed, install the new seal(s). 13. On the 275hp model, Apply a coalirigof Loctite • 271, or equivalent. to the outside diameter of the seal. b. Place the seal onto the carrier with the lip ol the seal lacina UP. c. Using a deep socket or mandrel the same diameter as the seal, tap the seal flush with the top of the carrier. d. Lubricate the 0-ring with bearing assembly lubricant and Install the 0-ring around the seal carrier. e. Slide the seal carrier down the driveshaft and into the lower unit housing. Be sure the seal carrier is flush with the driveshafl bearing retaining nut. Apply a small amount of silicone sealant to the ends of the divider plate and install the plate into the housing. 14. On the 225hp model, Place the first seal, with the seal lip lacing up into the bore of the carrier. a. Press the seal into the carrier with a mandrel or deep socket. b. Place the second seal into the carrier with lhe lip of the seal facing down, (seals should be back-to-back). Step 14 Coupling -....g 0-ring ....9. housrng I: IIG•••·· -Q I Face C . Iarner .... 0-ring --..o Oil _...... seal -..® 03'139Gl9 6-20 LUBRICATION AND COOLING Water , base ..i1' . Step 15 Step 16 Water pump Step 17 Thermostat S1ep 20 c. Press the seal into the carrier with a mandrel or deep socket until it con tacts the other seal. d. Lubricate the 0-ring with bearing assembly lubricant and install the 0-ring around the carrier. e. Slide the carrier down the driveshaft and into the lower unit housing. Be sure the carrier is flush with the driveshalt bearing retaining nul. f. Install the Iiller block into the housing behind the driveshat\. 15. Place a new gasket in place on the lower unit. Slide the water pump base down over the driveshaft. Tap the base down lightly to seal it over the gasket. 16. Slide the gasket and then the outer plate down the driveshalt. 17. Coat the impeller drive pin area ol the driveshalt with water resistant multipurpose lubricant. 18. Position the impeller drive pin on the nat spot on the driveshaft. The lubricant will hold the pin in place. 19. Slide a new impeller down lhe driveshalt and over the drive pin. ,.II at all possible, always install a new water pump impeller. If the old impeller must be Installed, install the impeller in the same position to allow the vanes to rotate in the same direction as the original installation. II the impeller is installed causing the vanes to rotate in the opposite direction, premature impeller failure of the impeller will surety occur. 20. Apply a thin coating of water resistant multi-purpose lubricant to the inside diameter ol the water pump cover. Apply Loctite '* 271. or equivalent, to the threads of the four securing bolls. 21. Slide the cover down the driveshalt. Rotate the shalt clockwise and at the same time push down on the pump cover to ease entry of the impeller into the cover. 22. Install the water pump cover retaining bolts, washer, and isolators. Tighten the bolts to a torque value of 60 inch lbs. (6.8Nm). 23. Slide the sealing ring down the driveshalt onto the top of the water pump cover. 24. Apply a coaling of water resistant multi-purpose lubricant around the inside diameter of the water tube grommet as an aid in later assembly to the water tube. CLEANING & INSPECTION Clean all water pump parts with solvenl, and then dry them with compressed air. Inspect the water pump cover and base for cracks and distortion. If possible, always install a new water pump impeller while the lower unit is disassembled. A new impeller will ensure extended satisfactory service and give "peace ol mind" to the owner. If the old impeller must be returned to service, never install it in reverse to the original direction of rotation. Installation in reverse will cause premature impeller failure. Inspect the ends of the impeller blades lor cracks, tears, and wear. Check for a glazed or melted appearance, caused from operating without sulficient water. If any question exists, as previously stated, install a new impeller il at all possible. REMOVAL & INSTALLATION • See Figures 19 thru 27 1. Locate the thermostat cover. 2. Remove the retaining bolts or screws. 3. Carelully remove the thermostat cover. 4. If the cover does not want to come loose, tap it gently with a plastic hammer. 5. Remove the thermostat cover. 6. Remove the thermostat gasket. 7. Remove the thermostat fiOm the housing. To install: 8. Throughly clean the gasket mating surlaces. 9. Alter thoroughly inspecting, cleaning and testing the thermostat, install a new gasket and then install the thermostat. 10. Install the housing cover and tighten the bolts snugly. fig. 19 Thermostat and housing assembly-6 to 15hp model :r Manual Model LUBRICATION AND COOLING .. ThotmOWI(c-G.uMrf 8 C.rrior (6196618 1 Bollr- 2 Tl'lenr.Cowt-·8l7ZStV1 3 Thttmc&t-.t eo.--OasJ36T.rA.res.MO:r 4·Wt.nw.gHI)tfl 7 •Remct:rt Controtlie!'MM 2·WamTA9Mc!Wit 3 •Torml!'laJ Oiod< 5·lgnitlonS'I.lkn 6•EngineKllmcss Fig. 30 Typical warning horn wiring diagram 8-L.owOJS..w 05156G31 Fig. 31 Typical low oil quantity sending unit in the reservoir :r reservoir oil tank cap. When the float descends to a predetermined level, a signa tis sent directly to the Warning Module mounted on the powerhead. The warning module completes the circuli and tile horn ln the remote control shift box sounds. In most cases there is sufficient running time-approximately 30 to 35 minutes at full throttle-tor the operator to return to shore and service Ule main oil tank in the boat. f'.s mentioned earlier, all models equipped with oil Injection are also equipped with a Warning Module or ECU warning system. Test Button Model (If equipped) When the ignition key Is placed in Ule run position and the Test button. on the oil tank is depressed-the warning horn will sound with a continuous "Beep" tone. This test verifies both the overheat and low oil quantity warning circuits are functioning properly. There is only one tone sound for both the overheat and low oil quantity warnings on these models. Warning Module • See Figure 32 When the ignition key ls placed in tile RUN position, the warning module begins a self test mode. Two dilferen...tones are used to warn the operator of a powerhead problem. The first warning fane is a brief steady "l:leep· verilying the overheat warning system is functioning. The next tone, is a series of short "Beep-Beep .. tones verifying the low oil quantity circuit is functioning properly. An oil tank gauge kit for the remote oil tank mounted in the boat is available from the Mercury/Mariner dealer as an accessory. The kit comes complete with a control panel gauge, remote oil tank sender unit, and necessary wiring. This gauge unit provides the operator a visual indication of oil quantity in the main tank. Fig. 32 Typical oil pump, fuel pump, and warning module installed on a V6 powerhead. Oil Quantity Gauge The oil quantity gauge operates on the variable resistance to ground principle. A moveable II oat arm on the sending unit rises and falls as the oil quantity changes. A variable resistor or rheostat is connected to the opposite end of the lloat arm. When the oil level decreases-resistance is Increased-allowing less current to flow through the gauge. Since the reduced current passes through the gauge, a bi-metal strip in the gauge coots proportionately and moves the needle toward a higher mark on the gauge face. Resistance is lowest when the oil tank is full. f'.s the oil quantity begins to drop, the resistance increases, causing more current to pass through the gauge. The bi-metal strip begins to heat-up and moves the needle towards a lower gauge indication. OVERHEAT TEMPERATURE WARNING The powerheads are equipped with an Overheat Temperature Sensor mounted in the cylinder cover. II the temperature should exceed a set temperature during powerhead operation, the overheat temperature sensor in the water jacket cover will close. When sensor closes, the circuit to the horn or warning module is completed and the LUBRICATION AND COOLING 6-23 horn in the remote shift box will sound-with conlinuous steady "Beep" tone to warn the operator of the overheat condition. Water Temperature Sensor 3D-40 (2-CYL/NOER) Uses the Timing Protection Module (TPM) to provide control of overheating and low-oil conditions. Warning is provided through the activation of a continuous tone warning horn lor either condition. An over-heat condition occurs when the engine temperature rises above 182-198°F (75-1WC). TheTPM will intermittently interrupt the ;giiilion voltage to the capacitor discharge modules (CDM) to reduce lhe maximum rpm to approximately 2500. The rpm will be limited and the warning horn will activate until the engine temperature drops below 162-178°F (64-90°C}. 40 HP (4-CYL/NOER), 5D-60 HP (3·CYLINOER) When the ignition key is initially turned on, the warning module will briefly provide a self-test of its engine overheat warning system. This will be a steady BEEP tone. If the powerhead temperature should exceed 300°F (65°C). the overheat temperature sensor in the water jacket cover will signal the IVl!rning module to activate the warning horn. 7D-115 HP When the ignilion key is initially turned on. the warning module will briefly provide a self-test ol lts engine overheat warning system. This will be a steady BEEP tone. 135-200 HP AND 275 HP If the temperature exceeds approximately 190"F (SJOC) the overheat temperature sensor in the water jacket of the cylinder head will close, completing a circuit to the warning module. The warning module will activate tile horn in the remote shift box. This warning horn will sound a continuous steady "Beep· tone to warn the operator of the overheat condition. 225 HP • See Figure 33 The temperature sensor is activated if the powerhead temperature exceeds 200°F (93.3°C}. The temperature sensor signal is relayed to the electronic control unit (ECU). If an overheat condition should develop, the ECU will perform two functions. First, it will activate the warning horn In tile remote shift box alerting the operator ol the condition. Secondly, it will retard powerhead timing, restricting powerhead speed Fig. 33 An optional temperature gauge sending unit may be mounted in the starboard head, below the No. 1 spark plug. .. ... .. . . 6-24 LUBRICATION AND COOLING to a maximum of 3,000 rpm. Once the powerhead temperature drops below 190°F (87°C}, the ECU will shut off the warning horn and restore lull timing functions for normal powerhead operation. Temperature Gauge -Temperature warning systems utilized on many of today's outboards no longer require the use of a temP.erature gauge lor the operator to monitor. The following is a brief description of atemperature gauge system. The temperature gauge must have a 12-volt power and ground wire connected to the gauge. A sensing wire from the gauge should be connected to the temperature sending unit on the powerhead. When the ignition key switch is set to the run position,the bi-metallic resistor in the sending unit will have little or no resistance. As the powerhead begins to warm to normal operating temperature, the resistance increases causing the needle on the gauge to move. As powerhead temperature increases. the more resistance and consequently more gauge needle movement TESTING 1. To test the temperature gauge perform the following: • Set the key switch to the RUN position and then disconnect the sensor wire at the sending unit • Make contact with the sensor wire to a good powerhead ground. The gauge should move full scale. • If the gauge i\ioves-replace the sending unit,if no movement is observed__.,;heck for 12-volts at the gauge unit and the ground connections. • Repair defective wire connections or replace the gauge. 2. To test the temperature warning light • When the ignition key is turned on, the light assembly is supplied with 12volts and grounded through the sending unit mounted on the powerhead. When the temperature switct\ makes contact-because the water temperature has reached an unsafe figure-the circuit to ground is completed and the lamp should light. • Set the ignition switch torun. Disconnect the wire at the sending unit, and make contact with the wire to a good powerhead ground. The lamp on the control panel should light. If the lamp does not light. check for a burnedout bulb or a break somewhere in the wiring to the light. Troubleshooting the Warning Systems Thermomelt Sticks • See Figure 34 Thermomelt sticks are an easy method of determining if the powerhead is operating at the proper temperature. Thermomelt sticks are not expensive and are available at most local marine dealers. 1. Start the powerhead with the propeller in the water and operate it for about five minutes at roughly 3000 rpm, allowing it to warm to normal operating temperature. Fig. 34 A thermomelt stick is a quick, simple, inexpensive, and fairly accurate method of determining the operating temperature of the powerhead. ** CAUTION Water must circulate through the lower unit to the powerhead any time the unit Is operating to prevent damage to the water pump in the lower unit. Just five seconds without water will damage the water pump. 2. The 140 degree stick should melt when it makes contact with the lower thermostat housing or on the top cylinder. If it does not melt, the thermostat is stuck in the open position and the powerhead temperature is too low. 3. Make contact with the 170 degre.._stick to the same spot on the tower thermosial housing or on the top cylinder. The stick should NOT melt. If it does melt, the thermostat is stuck in the closed position or the water pump Is not operating properly because the powerhead is operating too hal If the power head is not equipped with a thermostat,the problem may be solved by reverse llushing to clean out lhe cooling system and/or servicing the water pump. See the service procedures lor the thermostat and water pump. Water Temperature Sensor REMOVAL & INSTALLATION 30-40 HP (2-Cylinder) • See Figure 35 1. Disconnect the sensor wires at the bullet connectors. 2. Remove the retaining bolts and lin out the sending unit. To install: 3. Clean the sending unil and all mating surfaces. Make sure that no corrosion or foreign objects are fouling the tip of the sending uniL 4. Install the sending unit in the cylinder head. 5. Tighten the retaining screws snugly. Do not overtighten. 40 HP (4-Cylinder) • See Figure 36 1. Dis connect the temperature switch at the bullet connector. 2. Remove the temperature switch lrom the cylinder block cover. To install: 3. Clean the tip ol the temperature switch and reinstall il back into the cylinder block cover. 4. Tighten the switch snugly. Do not overtighten the switch. 40-60 HP (3-Cylinder) • See Figures 37 and 38 1. Disconnect the temperature switch at the bullet connector.2. Remove the retaining screw and remove the temperature switch from the cylinder head. 051!lSG27 Fig. 35 Location drawing of both the new and old style temperature sending units LUBRICATION AND COOLING 6-25 1 -Plug(Remove for Installation of Water Pressure or Water Temperature Gauge Kit) 2 Temperature Switch IX>IS6G26 Fig.36 Location of the water temperature switch and optional temperature or pressure gauge plug 05196628 Fig.37 4HOhp model water circulation To install: 3. Clean the tip of the temperature switch and 0-ring seal and reinstall il back into the cylinder block cover. 4. Tighten the switch snugly. Do not overtighten. 71H75 HP • See Figure 39 1. Disconnect the temperature switch at the bullet connector. 2. Remove the screw and retainer and remove the temperature sensor from the cylinder head. ..Afterremoving the screw and retainer from the overheat sensor, insertinga small flat-tip screwdriver between the sensor and the cylin :r , '· 1 -Temperature Switch 0!>19..19 Fig.38 The temperature switch is located in the outer side of cylinder head as shown 1-Screw2-Retainer 3-Overheat Sensor 05195G31 Fig.39 The temperature switch is located in the outer side of cylinder head as shown I ,_ 6-26 LUBRICATION AND COOLING der block will break the adhesion of the 0-ring seal to the block and aid in the removal of the sensor. To install: 3. Clean the tip of the temperature switch and 0-ring seal and reinstall it back into the cylinder block cover. ·4. Tighlen the switch snugly. Do not overtighten. TESTING 31}-60 HP • See Figure 40 1. During normal engine operation. the temperature switch is open. The switch will close when the temperature reaches 182-198°F (84-92°C). The switch will reset back to an open circuit at 162-178"F (73-81°C}. 2. Place the switch end into water with a thermometer and heal the water to 182-198°F (84-92°C). 3. Take the switch out and perform an ohms test to check when the switch resels. 4. If the switch does not meet specification. it wi II need to be replaced. 71}-115 HP 1. During normal engine operation, the temperature switch is closed. The switch will open when the temperature reaches 162-178•F (69-85°C). The switch will reset back to an closed circuit at 182-198°F (80-96°C}. 2. Place the switch end into water with a thermometer and heat the water to 182-198°F (8D-96.C) 3. Take the switch oul and as it cools, perlorm an ohms test to check when the switch resets. 4. If the switch does not meet specification, it will need to be replaced. 135-225 HP 1. During normal engine operation, the temperature switch is open. The switch will close when the temperature reaches 232-248°F (102-129°C). 2. Place the switch end into water with a thermometer and heat the water to 232-248°F (102-129°C). 3. Take the switch out and as it cools, perform an ohms test to check when the switch resets. 4. If the switch does not meelspecification, it will need to be replaced Oil Gauge TESTING 1. Set the key switch to the RUN position. 2. Disconnect the sensor wire at the remote oil tank sending unit 3. Make contact with the sensor wire to a good powerhead ground. The gauge should move towards empty. 4. If the gauge moves, replace the sending unit. 5. If no movement is observed. check for 12-volts DC atthe gauge terminal embossed "I" and for a good ground connection at terminal "G". 6. Repair the damaged wire connections or replace the detective oil quantity gauge. Oil Level Switch TESTING 1. Disconnect both low oil sensor leads lrom the terminal connections. 2. Connectan ohmmeter between both leads. 0519EG30 Fig. 40 Performing an ohms test on the temperature switch 3. There should be NO continuity through the sensor. 4. If continuity exists, the sensor is faulty and must be replaced. REMOVAL & INSTALLATION 1. On the 40hp models with conslant-ralio oil injection, lilt the oil reservoir enough to access the bottom ol the oil reservoir. 2. Remove the screw securing the low-oil sensor to the bottom of the reservoir and remove the sensor. 3. On the 50-60hp models with constant-ratio oil injection, disconnect the oil sensor wires at their bullet connectors. 4. Disconnect the oil outlet hose and remove the oil reservoir I rom the engine. 5. Remove the low-oil sensor from the bottom of the reservoir. 6. On the 75-125hp models equipped with variable-ratio oil injection, disconnect the low-oil sensor wires at their bullet connectors located at the bottom ol the oil reservoir. 7. Disconnect and plug any oil lines at the oil reservoir fitting. 8. Remove the starter motor upper mounting bracket and the screws securing the reservoir upper support brackel 9. Remove the reservoir lower support screw and remove the oil reservoir. 10. Remove the low-oil sensor lrom the bottom of the oil reservoir. 11. On the 135-275hp V-6 models equipped with variable-ratio oil injection, the engine mounted reservoir is equipped with a float-type low-oil sensor built into the oil reservoir fill cap. 12. Disconnecl lhe oil level sensor wires at their bullet connectors and remove the cap and sensor assembly. To install: 13. On the 135-275hp models, connect the oil level sensor wires and replace the oil reservoir cap and sensor assembly. 14. On the 75-125hp models, install the oil level sensor into the bottom ol the oil reservoir and secure it with the retaining screw. 15. Install the oil reservoir lower support screw and oil reservoir on the powerhead. 16. Install the starter motor upper mounting bracket and secure the oil reservoir to the upper support bracket. 17. Reconnectthe oil level sensor wires at their bullet connectors. 18. Connect the oil lines to the oil reservoir fitting .. 19. On the 4D-60hp models, install the oil level sensor assembly into the botlam ollhe oil reservoir and secure it. 20. Install the oil reservoir onto the powerhead and secure it in place. 21. Connect lhe oil lines. 22. Connect the low-oil sensor wires at their bullet connectors. ..OPTIMAX WARNING SYSTEMS Description and Operation 1991h99 MODEL YEARS The outboard warning system incorporates a warning light gauge and warning horn. The warning horn is located inside the remote control or is part of the ignition key switch wiring harness. When the key switch is turned to the ON position. the warning lights and horn will turn on lor a moment as a system test to let the operator know the system is operational. low Oil level The system is activated when the oil in the engine mounted oil reservoir drops below 50 fl. oz. (1.5 liters). You will still have an oil reserve remaining lor 50 minutes of full speed operation. .-The engine mounted oil reservoir along with the remote oil tank will need to be refilled. The OIL light on the gauge will come on and the warning horn sounds a series of four short tones. If you continue to operate the engine, the light will stay on and the horn will sound four short tones every two minutes. The engine needs to be shut down to reset the warning system. No Oil Flow To The Electric Oil Pump The system is activated when the !low of oil to the oil pump is blocked. No lubricating oil is being supplied to the engine. Stop the engine as soon as possible or severe engine damage will occur. The OIL light and the CHECK ENGINE light will come on and the warning horn will begin sounding. The warning system will automatically reduce and limit the engine speed to 3000rpm. The engine has to shut down to reset the warning system. Engine Overheat The syslem is activated when lhe engine temperature is loo hot. The TEMP light will come on and the warning horn will begin sounding. lhe warning system will automatically limit the engine speed to 3000rpm. After the engine has cooled, shift the outboard into neutral to reset the warning system. Ignition Coil, Sensor or Injector Not Functioning The system is activated if an ignition coil, sensor or injector is not working properly. The CHECK ENGINE light will come on. Throttle Sensor Not Functioning The system is activated ifthe lhrottle sensors are not working properly. The CHECK ENGINE light will come on and the warning horn will begin sounding Water Separating Fuel Filler Full of Water The water level detection warning is activated when water in the water separating fuel filter reaches the full level. The water can be drained from the filter. The WATER DETECTION light will come on and the warning horn will begin sounding aseries of four beeps. As the engine continues to be operated, the light will stay on and the horn will sound every two minutes. Engine Over-Speed Protection The system is activated when engine speed exceeds the maximum allowable rpm. anytime the engine over-speed system is activated, the warning horn begins to sound continuously. The system will automatically reduce the engine speed to within the allowable limits. .-Engine speed should never reach the maximum limit to activate the warning system unless the propeller is ventilating, an incorrect propeller Is being used or the propeller itself is faulty. LUBRICATION AND COOLING 6-27 GUARDIAN PROTECTION SYSTEM-2000 The Guardian Protection system monitors critical engine functions and will reduce engine power accordingly in an attempt to keep the engine running within safe operating parameters. :::::: WARNING The Guardian System cannot guarantee that powerhead damage will not occur when adverse operating conditions are encountered_ The Guardian System is designed to (1) warn the operator that the engine is operating under adverse conditions and (2) reduce power by limiting maximum rpm in an attempt to avoid or reduce the possibility of engine damage_ Smartcraft Warning System t See Figure 41 The SmartCratt warning system incorporates the display screens and warning horn and the Guardian Protection System. The warning horn is located inside the remote control or is part of the ignition key switch wiring harness. 3050 RPM,a. Display screens b. Engine guardian sys c. Flashing alarm signal Fig_ 41 SmartCraft warning system gauge display Alarm Warnings When a problem is detected, lhe warning horn sounds and the name of the alarm appears in the display on the gauge face. Ifthe problem can cause immediate engine damage, the horn will sound continuously and the Engine Guardian System will respond to the problem bylimiting engine power. Immediately reduce throttle speed to idle and refer to the warning messages covered in the chart. Ifthe problem will not cause immediate engine damage, the horn will sound but not continuously The alarm message will stay displayed until the mode butlOn is pressed. If there are multiple alarms, these wfll cycle on the display at five second intervals. If the mode button is pressed to a different screen, the flashing alarm signal "AL" will appear in the upper right hand comer to indicate thatthere is still a problem Guardian Protection System Monitors the critical sensors on the engine for any early indications of problems. The system will respond to a problem by reducing engine power in order to maintain a safe operating condition. The display screen will show the percentage of power loss. GUARDIAN SYSTEM ACTIVATION • Engine overheat Engine power level can be reduced to any percentage down to idle speed. if an overheat condition persists • Air compressor overheat Engine power level can be reduced to any percentage down to idle speed. if an overheat condition persists • Block water pressure low: Engine power level can be reduced to any percentage down to a fast idle speed. if condition persists 6-28 LUBRICATION AND COOLING • Troubleshooting the Warning Systems Throttle position sensor failure: If the throttle position sensor tails or becomes disconnected. power will be limited to a maximum of approximately 4500 rpm. when the TPS is in the fail mode. the ECM will use the MAP sensor for a reference to determine luel calibration • Temperature sensor (cylinder head and air compressor) failure: If a temperature sensor should fail or become disconnected, power will be reduced 25 percent. • Battery voltage (too high or too low): Battery voltage greater than 16.5 volts or less than 10.5 volts will result in engine output power being reduced. The higher or lower the voltage is outside of these parameters, the greater the percentage of power reduction. In an extreme case, power could be reduced to idle speed. • Oil pump failure:If the oil pump faits or an open circuit occurs between the pump and the ECM, engine power will be reduced to idle speed. The DDT is used to troubleshoot the OptiMax series of engines. Attach the diagnostic cable to the ECM diagnostic connector and plug in the soltware cartridge. You will then be able to monitor sensors and ECM values including status switches. The ECM program can help diagnose intermittent engine problems. It will also record the state of the engine sensors and switches for a period of time and then can be played back to review the recorded information. Troubleshooting without the DDT is limited to checking the resistance on some ol the sensors. Typical failures do not usually include the ECM. Connectors, set-up and mechanical wear are usually at fault. Since this system share sensors with elller systems on the outboard, sensor testing and service is covered in both the "Fuel System· and "Ignition and Electrical" chapters. ;r ENGINE MECHANICAL 7-2 THE TWO-STROKE CYCLE 7-2 POWER HEAD 7-2 REMOVAL & INSTALLATION 7-2 REED VALVE 7-13 2.5-3.3 HP 7-14 REMOVAL & INSTALLATION 7-14 4-5 HP 7-14 REMOVAL & INSTALLATION 7-14 6-15 HP 7-15 REMOVAL & INSTALLATION 7-15 2Q-25 HP 7-15 REMOVAL & INSTALLATION 7-15 30 AND 40 HP (2-CYLINDER) 7-15 REMOVAL & INSTALLATION 7-15 40 HP (4-CYLINDER) 7-16 REMOVAL & INSTALLATION 7-16 40 HP (3-CYLINDER), 50 AND 60HP 7-16 REMOVAL & INSTALLATION 7-17 75-125 HP 7-17 REMOVAL & INSTALLATION 7-17 135-250 HP 7-17 REMOVAL & INSTALLATION 7-17 135-225 DFI OPTIMAX 7-18 REMOVAL & INSTALLATION 7-18 275 HP 7-18 REMOVAL & INSTALLATION 7-19 POWERHEAD RECONDITIONING 7-19 DETERMINING POWERHEAD CONDITION 7-19 BUY OR REBUILD? 7-19 POWERHEAD OVERHAUL TIPS 7-20 TOOLS 7-20 CAUTIONS 7-20 CLEANING 7-20 REPAIRING DAMAGED THREADS 7-21 POWERHEAD PREPARATION 7-21 CYLINDER BLOCK AND HEAD 7-22 GENERAL INFORMATION 7-22 INSPECTION 7-23 CYLINDER BORES 7-23 GENERAL INFORMATION 7-23 INSPECTION 7-23 REFINISHING 7-24 PISTONS 7-24 GENERAL INFORMATION 7-24 INSPECTION 7-24 PISTON PINS 7-25 GENERAL INFORMATION 7-25 INSPECTION 7-25 PISTON RINGS 7-26 GENERAL INFORMATION 7-26 INSPECTION 7-27 CONNECTING RODS 7-27 GENERAL INFORMATION 7-27 INSPECTION 7-27 CRANKSHAFT 7-28 GENERAL INFORMATION 7-28 INSPECTION 7-29 BEARINGS 7-29 GENERAL INFORMATION 7-29 INSPECTION 7-30 POWERHEAD EXPLODED VIEWS 7-30 TORQUE SEQUENCE DIAGRAMS 7-36 SPECIFICATIONS CHARTS ENGINE TORQUE SPECIFICATIONS 7-39 ENGINE REBUILDING SPECIFICATIONS 7-41 ,'• 7-2 POWERHEAD ENGINE MECHANICAL The Two-Stroke Cycle The two-stroke engine can produce substantial power for itssize and weight. But why is a two-stroke so much smaller and lighter than a tour-stroke? Well, there is no valvetrain. Camshafts, valves and pushrods can really add weight to an engine. A two-stroke engine doesn't use valves to control the air and fuel mixture entering and exiling the engine. There are holes. called ports, cut into the cylinder which allow for entry and exit of the fuel mixture. The two-stroke engine also fires on every second stroke of the piston, which is the primary reason why so much more power is produced than a four-stroke. Since two-stroke engines discharge approximately one fourth of their fuel unburned, they have come under close scrutiny by environmentalists. Many states have tightened their grip on two-strokes and most manufacturers are hard at work developing new efficient models that can meet the tough emissions standards. Check out your state's regulations before you buy any two-stroke outboard. The two-stroke engine is able to function because of two very simple physical laws. The first, gases will IIow from an area or high pressure to an area or lower pressure. A tire blowout is an example of this principle. The high-pressure air escapes rapidly if the lube isjlunctured. Second, if a gas is compressed into a smaller area. the pressure increases and il a gas expands into a larger area, the pressure is decreased. If these two laws are kept in mind. the operation of the two-stroke engine will be easier understood. 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 opened and closed 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. the pistons of mosttwo-stroke engines have a deflector-type top. This design of the piston lop serves two purposes very effectively. First, it creates turbulence when the incoming charge of fuel enters the combustion chamber. This turbulence results in more complete burning of the fuel than il the piston top were flal. Second. it forces the exhaust gases from the cylinder more rapidly. Beginning with the piston approaching top dead center on the compression stroke, the intake and exhaust ports are closed bythe piston. the reed valve is open, the spark plug fires, the compressed air/fuel mixture is ignited and the power stroke begins. The reed valve was open because as the piston moved upward, the crankcase volume increased, which reduced the crankcase pressure to less \han lhe outside atmosphere.As the piston moves downward on the power stroke, the combustion chamber is filled with burning gases. 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 increases, closing the reed valves against their seats. The crankcase then becomes a sealed chamber. The air/fuel mixture is compressed ready for delivery to the combustion chamber. As the piston continues to move downward. the intake port is uncovered. A fresh air/fuel mixture rushes through the intake port into the combustion chamber striking the top of the piston where it is deflected along the cylinder 1vaiL 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 lhe crankcase 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 full cycle has been completed. The exact time of spark plug firing depends on engine speed. Al low speed the spark is retarded, fires later than when the piston is at or beyond lop dead center. Engine liming is built into the unit at the factory. At high speed, the spark is advanced, fires earlier than when the piston is at top dead center. On all but the smallest horsepower outboards the timing can be changed adjusted to meet advance and retard specifications. Because of the design of the two-stroke engine, lubrication of the piston and cylinder walls must be delivered by the fuel passing through lhe engine. Since gasoline doesn't make a good lubricant, oil must be added to the fuel and air mixture. The trick here is to add just enough oil to the fuel to provide lubrication. If too much oil is added to the fuel, the spark plug can become "louted" because or the excessive oil within the combustion chamber. IIthere is not enough oil present with the air/fuel mixture, the piston can "seize" within the cylinder. What usually happens in this case is the piston and cylinder become scored and scratched, from tack of lubrication. In extreme cases. the piston will turn to liquid and eventually disintegrate within the cylinder. -Most two-stroke engines require that the fuel and oil be mixed before being poured into the fuel tank. This is known as "pre-mixing" the fuel. This can become a real hassle. You must be certain that the ratio is correct Too little oil in the fuel could causethe piston to seize to the cylinder, causing major engine damage and completely ruining your weekend. Most modern two-stroke engines have an oil injection system that automatically mixes the proper amount or oil with the fuel as it enters the engine. Powerhead REMOVAL & INSTALLATION When removing any powerhead, it is a good idea to make a sketch or take an instant picture of the location, routing and positioning of electrical harnesses. brackets and component locations lor installation reference. The following procedures assume that the outboard has been removed from the boat and placed on a suitable work stand. ti the powerhead is being removed with the outboard still mounted on the boat and the powerhead is equipped with an electric starter, disconnect first the negative, then the positive battery cables to prevent accidental starting. On some powerheads it will be necessary to remove attached components if the powerhead is to be overhauled. Reier to the specific sections covering these components for removal and Installation information. ,.Sometimes when attempting to remove the powerhead it won't come loose from the adapter. The gasket may be holding the powerhead. Rock the powerhead back and forth or give it a gentile nudge with a pry bar. II the gasket breaks loose and the powerhead still will not come loose, then the drivesh.aft Is seized to the crankshaft at the splines. 2.5-5 HP • See accompanying illustrations 1. On the 2.5-3.3 hp models, unsnap and lower lhe spark plug access cover. 2. Separate the cowling halves free of the powerhead and set them aside. 3. Pull the spark plug lead free or the spark plug. Use a pulling and twisting motion on the molded cap portion. Never pull on the wire or on the connector inside. the cap or boot may be separated or damaged. 4. Remove the spark plug. Take care not to till the socket as the plug is removed or the insulator may be cracked. 5. Remove the hand rewind starter. 6. Rotate the fuel shut-off valve to the off position. 7. Remove the clamp securing the fuel line to the carburetor or fuel pump and remove the nuts, washers and spacers securing the fuel tank to the powerhead. Lift the fuel tank free of the powerhead. 8. On the 2.5-3.3 hp models, remove the screws securing the throttle and choke knobs to each lever. Remove the screws securing the cover plate to the front of the carburetor. Slide the front plate forward, off the choke and throllle levers. Set the lronl plate to one side of the carburetor. 9. On the 4-5 hp models. loosen lhe screw securing the lhrollle wire to the throttle arm of the carburetor and then pull the wire through and free or the throttle arm. Disconnect the choke link rod at the carburetor by unsnapping the nylon clip from the link rod and rotating the nylon dip. Putt the link rod free of the carburetor choke shall. 10. Remove the screws securing the baffle cover to the front of the carburetor. POWER HEAD 7-3 Step2 :r Step 14 Step10 Step13 11. Remove the through bolts on the front of the carburetor and !iffthe carburetor free of the powerhead. 12. On the 2.5-3.3 hp models, disconnect the stop switch wire lead from the , '· carburetor front plate and then separate the wire lead going to the CD modu!e at the quick disconnect bullet connector. The front plate of the carburetor is now free. loosen the screw on the clamp securing the carburetor. Pull the carburetor away from the powerhead. 13. On the 2.5-5 hp models, obtain a strap wrench or equivalent tool. Hold the rope cup steady with the strap wrench and "break" the rtywheel nut loose, then remove the nut with the proper size socket. The nul has standard right hand threads. 14. Continue holding lhe rope cup with the strap wrench and remove the bolts securing the rope cup. 15. Obtain a universal puller and set-up the puller over the crankshaft. Use the holes from which the rope cup bolls were removed to secure the puller. Never attempt to use a puller which pulls on the outside edge of the flywheel or the flywheel 7-4 POWER HEAD Step 25 Step 28 Step 29 Step 30 may be damaged. After the puller is installed and ready, tighten the center screw onto the end of the crankshaft. Continue tightening the screw until the flywheel is released from the crankshaft. 16. After the flywheel is released, remove the puller and till the flywheel free of the crankshalt. A "pull" may be felt as the flywheel is lifted due to the permanent magnets installed on the inside rim of the flywheel. ,..Handle the flywheel c:arefully because any sudden shock (such as dropping the flywheel,) will lessen the strength of the magnets. A weak magnet will seriously affect the ignition circuit. lift out the Woodruff key from the keyway in the crankshaft. 17. On the 2.5 and 3hp models equipped with a magneto point ignition, disconnect the wire lead lrom the stator assembly to the secondary ignition coil on the side of the powerhead. Remove the boltssecuring the secondary ignition coil to the powerhead. 18. Remove !he screws securing the stator assembly. Lift the stator plate and at the same time feed the disconnected wire lead to the coil through the opening !n the cylinder block cover. 19. On 2.5-3.3 hp models equipped with CDI ignitions. disconnect all the wire bullet connectors on the side of the powerhead. Remove the bolts securing the secondary ignition coil and CD module to the powerhead. 20. Lift the CD module and secondary coil free of the powerhead. 21. Remove the screws securing the capacitor charging/trigger coil and the wire lead to the stator. Lift off the capacitor charging/trigger coil and at the same time, feed the wire lead through the opening in the cylinder block cover. 22. On the 4 and 5 hp models, disconnect the blade terminal from the secondary ignition coil. Now, remove the bolts securing the coil to the powerhead and lilt off the ignition coil. Disconnect ali the wire bullet connectors on the side of the powerhead. Pull the rubber bracket securing the CD module back and then lift the module from the rubber bracket. 23. Remove the screws securing lhe capacitor charging coil and the wire lead to ..Step 36 Step 37 tile stator. Ufl oil the capacitor charging coil and at lhe sametime. feed lhe wire lead through the opening in the cylinder block cover. 24. Remove lhe screws securing the trigger coil and wire lead. lift out lhe trigger coil and at the same time, feed the wire lead through the opening in the cylinder block cover. 25. On the 2.5-5 hp models. remove the bolls securing the powerhead to lhe driveshaft housing. 26. Carelully pry the powerhead free ol lhe drlveshaft housing. Itmay be necessary lo lap on \he joinl with a soft nead mallello break the powerhead loose. lift the powe(head straight up and clear ofthe driveshaft. .-11 the unit is several years old or If It has bean operated in salt water or has not had proper maintenance or shelter or any number of other factors, then separating the powerhead from the drlvesflaft housing may not be a simple task. An air hammer may be required on the studs to shake the corrosion loose; heat may be applied to the casting to expand it slightly; or otherdevices employed In order to remove the powerllead. One very serious condition would be the driveshall "frozen· with the crankshaft. In this case. a circular plug-type hole must be drilled and a torch used to cut lhe driveshaft. Let's assume the powerhead will come tree on the lirst attempt. To install: 27. Secure the lower unit in a holding fixture, vise equipped with soH jaws or any othersuitable restraining method, as an assist to Installing the powerhead and all !he supporting components. 28. Slide a new gasket down the driveshaH Into position on the driveshaft housIng. Now, lov."er the powerhead onto lhe driveshaH housing with the external splines on the lower end ol the cmnkshall indexing with the internalsplines ol the driveshafl 29. Install and lighten the bolts securing the powerhead to the driveshaft housIng. 30. Oo lhe 2.5 and 3.0hp with magneto ignition, hold the stator plate assembly over the powerhead. Feedthe wire from the stator plale through the opening in the base or the cylinder block cover. Now. lower the stator plate down over the crankshaft and into place. Secure the stator plate with Phillips head screws. POWER HEAD 7-5 Step 39 31. Install the secondary coil. on the pert side ot\he power head with the attaching bolts. Connect the Black/White wire leads from the staler and secondary coil together. 32. On 2.5, 3.0 and 3.3hp with COl, hold the capacitor charging/lrigger coil over the powerhead. Feed thewire !rom the capacitor chargingJtrigger coil through the opening in the base ol the cylinder block cover. Now. lower the capacitor charging/trigger coil down over the crankshall and into place. Secure the capacitor charging/trigger coil and wire lead clamp with Phillips head screws. 33. Install the secondary ignition coil and CO module onto the side ol lhe powerhead and secure ll with the bolls. Be sure lo slide the Black/While lead from the secondary ignition coil and the Black lead from theCD module with the large eyelets . onto lhe mounting bolt for the ignition coil. Connect the Orange lead to the Orange lead at the bullet connector and then the While lead to the White lead at \he bullet COMeciOr.34. On 4 and 5hp, Insert the trigger coil wire lead \hrougl\ the opening In the crankcase cover. Feed the wire leads through while lowering the trigger coli down into the crankcase cover recess. Secure \he trigger coil with Phillips screws, be sure to secure the trigger coli ground lead tenninal under one of the Phillips head screws. 35. lower the capacitor charging coil wire leads down through the opening In the crankcase cover. Guide the wire leads while lowering the capacitor charging coli down into the crankcase cover. Secure the capacitor charging coil and wire lead clamp with Phillips head screws. 36. Insert the CD module info the rubber bracket on the port side ol the powerhead. 37. Install \he secondary ignilion coil onto the port side ol the power head and secure it with the bolts. Be sure toslide the Black leads. one from the CO module and one from lhe stop button, onto one of the mounting boltslor the Ignition coil. 38. Connect the wire leads asfollows: Brown toBrown, Black/Red to Black/Red. Whiteto White, RedJWhite to Red/White and Black/Yellow toSecondary coil terminal. 39. Place the Woodruff lrey into the groove ol the crankshafl Slide \he flywheel down the crankshaft with the groove in lhe llywheel indexed over the key on the crankshaft. Rolale the llywheel clockwise and check tobe sure the llywheel does not make contact with any part of the ignition and/or components around the llywheel. 7-6 POWER HEAD Step 48 40. Install the flywheel nut and tighten lhe nut to the torque value listed in the . AppendiX. Use the same method of holding the llywheel as used lor disassembling. 41. Install the rope cup and secure i! in place with the attaching bolts. Use a strap wrench or similar tool to prevent the rope cup from rotating while the bolts are being tightened. 42. On 2.5, 3.0 and 3.3hp, slide the carburetor onto the intake manifold and ,. secure it in place with the clamp. '· 43. Position the carburetor front cover plate over the throttle and choke levers and secure the cover plate with screws. Place the lhrottle knob and choke knob onto the ends of the levers and secure with screws. 44. Connect the Black/White wire lead from the cover plate to the Brown wire lead lrom the CD module or the Black/White lead from the stator il the model has points. 45. On 4 and 5hp, place the carburetor and a new carburetor gasket against the crankcase cover. Insert the bolts and washers through the baffle bracket, carburetor Step 49 and into the crankcase cover. Tighten the bolts lirmly. Secure the baffle cover to the bracketwith screws. 46. Connect the throttle cable and choke linkages. 47. Place the fuel tank in position over !he powerhead and then secure it with the spacers, flat washers,locking washers and nuts. 48. Connect the fuel line directly to the carburetor bowl fitting or fuel pump inlet fitting on the side of the carburetor. Turn the fuel shut-off valve to the ON position. 49. Install the hand rewind starter onto the powerhead and secure in place with attaching bolts. 50. Thread a new spark plug into the powerhead and tighten it to the torque value listed in the Appendix. 51. Connect the spark plug high tension lead onto the spark plug. 52. Snap the spark plug access cover into place. 6-25 HP • See accompanying illustrations 1. Remove the engine cover. 2. Disconnect the spark plug leads and remove the spark plugs. , Step 10 3. Remove the hand rey.rind starter assembly 4. Remove the flywheel and stator assembly. 5. Remove the ignition coil and switch box. 6. Remove the carburetor. 7. Disconnect the tattle-tale hose (if equipped) from the fitting at the bottom of the cowling. Disconnect the shift rods and remove the bolts securing the throttle shift control platform to the powerhead. 8. Remove the throttle and shift linkage. 9. On the bottom side of the lower cowling, remove the bolls and nuts securing the powerhead to the driveshaft housing. 10. Ull the powerhead straight up from the driveshaft housing to prevent tearing the gasket. 11. Place the powerhead onto a workbench in an upright position for disassembly. •If the crankshaft and driveshalt splines bind together and do not sepa· rate smoothly when the powerhead is being lilted, it is possible the driveshaft pulled up/out of the gear housing and has disengaged the water pump Impeller key. 12. Measure the height of the driveshaft to determine if the driveshalt has pulled up/out of the gear housing as follows: Place a straight edge across the driveshaft housing where the powerhead was previously mounted. Measure the distance between the straight edge and the top of the driveshaft, as shown. Next, push down on the driveshaft until the driveshafl bottoms out in the gear housing. II the driveshalt moves downward more than % in. (6.35mm). it will be necessary to remove the gear housing and reinstall the water pump impeller key. 13. Disconnect the battery cables (if equipped). 14. Remove the nand rewind starter assembly. 15. Disconnect the spark plug leads and remove the spark plugs. 16. Disconnect the fuel hoses and remove the carburetor. 17. Remove the flywheel. stator assembly, trigger plate, swilchbox and the igni· lion coils. 18. Place the shift linkage in the neutral position. 19. Loosen the jam nuts that hold the control cables to the anchor bracket and remove the cables from around the p·ulley of the primary gear. 20. Disconnect the lower cable from the throttle/shift gear. Then, rotate the tiller handle twist grip all the way clockwise and disconnect the upper cable from the throttle/shift gear. 21. Remove the set screw holding the shill shalt coupler to the shift shaft. Slide the coupler oil the shaft. 22. Remove the 6 bolts securing the powerhead to the driveshaft housing and remove the powerhead from the driveshall housing. To Install: 23. Observe if the bottom cowling is separated from the driveshaft housing. If it is separated. install a new gasket between the cowling and the housing. 24. Position a new gasket over the powerhead studs and into place on the powerhead base. 25. Apply a thin coaling of Multipurpose Lubricant or equivalent, to the driveshalt splines. 26. Install the powerhead to ttle bottom cowling and driveshalt housing. II necessary, rotate the flywheel slightly to allow the coupler splines to index with the driveshaft splines and allow the powerhead to become fully seated. 27. Secure the powerhead to the bottom cowling and driveshaft housing with bolls and nuts on studs. POWERHEAD 7-7 Step 31 28. Apply Loclite* No. 35 thread sealing compound or equivalent to the threads of the bolls and studs. 29. Tighten the mounting bolts and nuts evenly, alternately and in stages to 200 inch lbs. (22.6Nm). 30. Tighten all bolts and nuts to%the torque value. ltlen repeat the sequence tightening to% the torque value. Finally, on the third and last sequence. tighten to the full torque value. 31. Connect the shift shaft coupler to the powerhead. 30 and 40 HP (2-Cylinder) 1. Disconnect the spark plug leads and remove the spark plugs. 2. On electric start models, disconnect the battery cables and remove them from the powerhead. 3. On manual start models. disconnect the s..lety lanyard switch, stop button assembly and the warning horn at the bullet connectors. 4. On electric start models, disconnect the remote control harness at the main wiring harness connector. Disconnect any additional remote control harness leads from the bullet connectors. II the unit is equipped with tilt and trim, disconnect the lower cowl switch leads at the bullet connectors. 5. Disconnect the neutral safety switch leads. 6. On the manual start models. disconnect the primer bulb lines from the intake manifold and carburetor fittings. 7. Remove the hand rewind starter assembly (if equipped). 8. On electric start models, remove the flywheel cover. 9. Disconnect the tell-tale water disctlarge hose from the fitting on the power· head. 10. On Hiler handle equipped models, remove the throttle cables. 7-8 POWER HEAD 11. On remote control equipped models, remove the throttle and shift cables. 12. Disconnect the fuel supply line from the lower cowl. 13. Remove the fasteners securing the trim cover to the driveshaft housing. 14. Remove the 6 screws securing the powerhead to the driveshafl housing. 15. Remove the plastic cap from the center of the flywheel and install the lifting e (91-90455) into the flywheel a minimum oiS turns. ey_ ,-At this point double check for any cables, hoses, wires or linkages that will inteifere with the removal of the powerhead. 16. Move the powerhead back and forth to break the gasket seal between the powerhead and driveshaft housing. When the seal breaks loose, lift the powerhead off the driveshafi and driveshaft housing using a suitable lifting hoist. 17. Remove the powerhead to a clean work area and placed in a suitable holding fixture secured in a vice. To install: 18. Throughly clean all old gasket material from the driveshaft housing and powerhead mating surfaces. 19. Lubricate the splines on the driveshaft with Quicksilver Special Lubricant No. 101 or equivalent Wipe off any excess lubricant from the top of the driveshaft. 20. Place a new gasket onto the driveshaft housing. 21. Install the powerhead on the driveshaft housing. You may have to rotate the crankshaft to index thJ!. crankshaft and driveshaft splines. 22. Apply Ouicksllver Perfect Seal or equivalent to the powerhead mounting screws. Install and tighten evenly to 29 ft. lbs. (39.3Nm). 23. Install !he trim cover over the driveshaft housing. Tighten the fasteners securely. 24. Reconnect the tell-tale hose at the powerhead fitting. 25. Install !he fuel supply line connector to the lower cowling. 26. On tiller handle equipped models, reinstall and adjust the throttle cable. 27. On remote control equipped models, reinstall the throttle and shaft cables. 28. Install the hand rewind starter (if equipped). 29. Install the flywheel cover. 30. On manual start models, connect the primer bulb lines to the intake manifold and carburetor fittings. 31. 32. On manual start models, connect the safety lanyard switch, stop button Connect the neutral safety switch lead connectors. switch and warning horn to the engine wiring harness. 33. On remote control equipped models, connect the remote control harness to the main wiring harness connector. Make sure to reconnect any remaining remote control harness leads. 34.35. On electric start equipped models, connect the battery cables. Install the spark plugs and reconnect the spark plug leads. 40-oo HP (3-Cylinder) • See accompanying illustrations 1. Disconnect the engine battery cables from the battery terminals. 2. Disconnect the engine fuel line from the fuel tank. 3. Remove the front engine cowling cover. ,, . : 4. Remove the port and starboard halves of the engine cowling. 5. Separate the electrical extension harness connectors. 6. Disconnect the remote control cables from the powerhead. 7. Stop and carefully observe the wiring and hose connections before proceeding. Because there are so many different powerheads and the arrangement is slightly different on each, it is not possible to illustrate each and every one. Even if they were shown, the reader would not be able to identity the powerhead being serviced. Therefore, Take time to make notes and tag the wire leads and hoses. You may elect to follow the practice of many professional mechanics by taking a series of photographs of the powerhead, one from the top and a couple from the sides showing the wiring and arrangement of parts. 8. On the 50 and 60 hp models, disconnect both leads from the battery. 9. Disconnect the first Black cable from the lower lerminat on Ihe cranking motor. 10. Disconnect the second large Black cable from the upper terminal on the cranking motor. 11. Make sure to identify Ihe Black cables connected to the starting motor on the 50 and 60 hp powerheads. One of the bracket securing bolts also secures the oil tank to the powerhead. 12. Remove the bolls securing the cranking motor bracket, the third large Black cable and the oil injection tank to the powerhead. 13. Remove the bracket and cranking motor from the powerhead. 14. Disconnect the high tension leads from the spark plugs. Always use a pulling and twisting motion as a precaution against damaging the connection. 15. Remove the spark plugs. 16. Remove the bolts securing the cover to the electrical box. The ignition switch box, ignition coil, fuse, starter solenoid and rectifier/regulator are all mounted inside the electrical box. All these electrical components will be removed as an assembly when the box is removed. 17. Disconnect the White/Black, Purple, Brown and White leads between the electrical box and the stator and trigger assembly. 18. Disconnect the wiring harness connector. 19. Locate the low oil warning module secured to the inside of the lower powerhead cover and disconnect the following leads: Tan, Purple, light Blue leads and a Black ground eyelet lead. 20. Remove the bolts securing the module to the cover and remove lhe module. 21. Remove the securing hardware and lift out the electrical box with all electrical components undisturbed. 22. Disconnect the Blue/While, Green/While and Red/Black leads a! the trim switch located on the side of the lower power head cover. 23. Remove the screws securing the cover to the air box. 24. Remove the long bolts securing the carburetors to the intake manifold. The carburetors are held together as an assembly by the forward straps, throttle and choke linkage and fuel tines. 25. Disconnect the fuel supply line and the primer line, if equipped. 26. Disconnect the fuel line between the enrichener valve and the fitting on the fuel bowl of the top carburetor and the tine between the valve and the fitting at the base of the oil pump. 27. lilt off the carburetors, as an assembly, with linkage and fuel lines between the carburetors still intact. Step 7 Step 11 03560012 Step 27 .• 28. Disconnect the leads from 1he low oil sensor, located at the base ofthe oil lank. at !heir quick disconnect fittings. II lhe oil tank contains oil, make arrangements to plug lhe oil line once il ls pulled free of the fitting, to prevent oil from spilling into lhe lower POWerheadcove.. Snip lhe tie wrap from the oil supply line, from tile tank. at lt:eoil injection pump.EaseIhe line free ol the frtting on lhe pump and lift outlhe oil tank. 29. Disconnect lhe oil outlet line bel\\--een the pump and the 2 psi check valve next tofileluel pump. Remove lhe attaching bolls and remove the oil pump from the powerhead.30. Snip the lie wraps a10und the inlet, outlet and pulse lines at the fuel pump. Remove the Phillips head screws securing the pump to the powerhead. Lift off lhe pump. 31. Remove lhe lop bolt securing the barrel retainer over lhe control cable barrels. Swing the retainer down to clear bolh barrels. 32. Remove the Jocknuls and washers securing the tllroftle and shill cable ends to the throttle lever and shift actuator stud. Slide the cables and barrels away from the barrel receptacles cast into lhe block and lilt both cables clear. 33. Make a final check to make sure no other leads or attachments will impede the removal ol the powerhead. 34. Remove the bolts securing the lower powerhead cover to lhe intermediate housing and remove the cover. 35. Next. remove the bolls securing the powemead to the i11termediate housing. 36. Remove the wing ..uts securing the plastic flywheel cover to the power- head. 37. Remove I he plastic cap from the end of the crankshaft. 38. Thread a lilling eye onto the end of the crankshaft as far as .. will go. 39. Using a suitable hoist, lilt lhe powerhead assemllly clear of the intermediate housing. 40. After lifting olf the powerhead, remove all traces ott hebase gasket. 41. Mounl lhe powerhead onto some type of stand, to facilitate easy access to all parts. Never allempt to mount the powerhead in a stand secured in a vise. Such an atlempl will only lead to damage of the powerhead and possible personal injury. 42. Remove the lift•ng eye from the crankshaft. To install: 43. Thread a lifting eye onto the end of the crankshaft as far as il will go. For safety, check lo be sure lhe lining eye is praperly installed. 44. Using a suitable holst, lift the powerhead. Place a new gaske! around the powerflead studs and into position on the base of the intermediate housing. 45. Lubricate lhe driveshaflsplines with multipurpose lubricant Wipe on any excess lubricant from the lop of the driveshafl. 46. Slowly lower the powerhead down onlo the intermediate housing. It may be necessary to rotate lhe flywheel slightly to Index the crankshaft splines with the drivesnan splines . Step 3 Step 7 POWER HEAD 7-9 47. Once the splines index. lower lhe powerhead fully into place on the intermediate housing. 48. Secure the powerhead to the intermediate housing with the bolts. Tighten the bolls In stages to 28 h. lbs. (38Nm). 49. Install !he lower cover around the intermediate housing and secure the cover in place with the bolts. Tighten lhe bolls to 80 inch lbs. (9Nm}.50. Disconnect the holst from tile lifting eye and then remove the eye I rom the crankshaft. Install tile plas!Jt cap onto lhe end of lhe cranksha!L Install the flywheel cover and secure it In place with nat washers and wingnuts. 51. Reconnect tile tell-tale hose a\ the powerttead fitting. 52. Install the fuel supply line connector to he lower cowiing.53. Reinstall the throttle and shaft cabtes:54. Install the ltywheel cover. 55. Connect the remote control harness to the main wiring harness connector. Make sure to reconnect any remaining remote control harness leads. 56. Connect the baltery cables. 57. Install the spark plugs and reconnect the spark plug leads. 40 HP (4-Cylinder) • See accompanying Illustrations 1. Disconnecl lhe batlery leads at the battefY. 2. Disconnect lhe fuel line at the powerhead fuel connector. 3. Remove lhe top cowling from the powerhead. 4. Disconnect the spark plug leads and remove the spark plugs. 5. Disconnect the remote control electrical con11ector at the powerhead. 6. Remove lhe positive lead from lhe cranking motor. Remove negative fead, clamps and bolls securing the cranking motor to powerhead. 7. Stop and lake lhe time now lo carefully observe the wiring and hose coMecllons before proceeding. 8. Stop and carefully observe lhe wiring and hose connections belo;e proceeding. Because there are so many diiJerent powerheads and tilearrangement is slightly different on each, it is not possible to illustrate each and ev&fY one. Even if they were shown. the reader would not be able lo identify the powerhead being serviced. Therefore, Taketime to make notes and tag the wire leads and hoses. You may elect to follow tile practice of many professional mechanics by taking a series of pholographs of the powerhead. one from the top and a couple from lhe sides showing tile wiring and arrangement of parts. 9. Remove the boll securing the fuel connector to the lower cowflng. Disconnect the hose from the tattle-tale fitting at the rear of lhe powerhead at the IO\\'l!r cowling. Remove the bolt securing the Black lead ground strap next to tile tattle-tale hose fitting. Step 8 7-10 POWERHEAD 10. Disconnect the inlet oil hose at the oil pump coming from the oil tank. Be sure to plug the end of the hose if there is any oil remaining in the tank, otherwise the oil will leak out of the tank. 11. Remove the bolts securing the flywheel cover to the powerhead. Lift off the cover and oil tank as an assembly. 12. Removethe bolts securing the trim cover below the lower cowling, Slide the coVer downward and aft until clear of the powerhead. 13. Remove the plastic cap from the flywheel and thread a lifting eye (91-75132) or equivalent into the flywheel. Turnthe lifting eye as tar as it will go but a minimum of five turns is required lor sale lilting. 14. Attach a hoist capable of lifting 500 lbs. or more to the lifting eye. 15. Remove the nuts from the studs securing -the powerhead to I he driveshalt housing. 16. Using a suitable hoist, lift the powerhead up and free of the driveshalt housing. _..II the unit is several years old or if it has been operated in salt water orhas not had proper maintenance or shelter or any number of other factors, then separating the powerhead from the driveshaft housing may not be asimple task. _..An air hammer may be required onthe studs to shake the corrosion loose; heat may h..ve to be applied to the casting to expand it slightly; or other devices employed in order to remove the powerhead. One very serious condition would be the driveshaft "frozen· with the crankshaft. In this case, a circular plug-type hole must be drilled and a torch used to cutthe driveshaft. To install: 17. Check to be sure old gasket material has been removed from the exhaust housing extension plate and the powerhead. These mating surfaces must beclean. Position a newgasket in place. 18. Thread a lifting eye ontothe end of the crankshaft as far as it will go. Use a suitable hoist and lower the powerhead onto theexhausthousing plate with the studs on the powerhead aligned with the holes in the exhaust housing. Use care to prevent the studs from damaging the gasket As the powerhead is slowly lowered. it will probably be necessary to rotate the flywheel slightly to allow the splines of the driveshaft to indexwith the crankshaft. 19. Thread the nuts onto the powerhead studs. Tighten the nuts alternately and evenly to 150 inch lbs. (16.9Nm). _...The nuts must be tightened to the required torque value In progressive stages. Tighten to %torque value, then% torque value and finally to the full torque value. 20. Remove the liftingeyefromthe crankshaft. 70-125 HP • See Figure 1 1. Disconnect the engine battery cables from the battery terminals. 2. Disconnect the engine fuel line !rom the fuel tank. 3. Remove the front engine cowling cover. 4. Remove the portand starboard halves of the engine cowling. 5. Separate the electrical extension harness connectors. 6. Disconnectthe remote control cables from the powerhead. 7. Stop and carefully observe the wiring and hose connections before proceeding. Because there are so many different powerheads and the arrangement is slightly different on each. it is not possible to illustrate each and every one. Even if they were shown, the reader would nol be able to identify the powerhead being serviced. Therefore, Take time to make notes and tag !he wire leads and hoses. You may elect to followthe practice of many professional mechanics by laking a series ol photographs ol the powerhead, one from the top and a couple from the sides showing the wiring and arrangementof parts. :r , 00658Pilll Step12 Step13 8. Disconnect both leads from the battery. 9. Disconnect the first Black cable from the lower terminal on the cranking motor. 10. Disconnect the second large Black cable from the upper terminal on the cranking motor. 11. Remove the bolts securingthe cranking motor bracket. the third large Black cable and Ihe oil injectiontank to the power head. 12. Remove the bracket and cranking motor fromthe powerhead. 13. Disconnect the high tension leads from the spark plugs. Always use a pulling and twisting motion as a precaution against damaging the connection. 14. Remove the spark plugs. 15. Remove the bolts securing the cover to the electrical box. The ignition switchbox, ignition coil, fuse. starter solenoid and rectifier/regulator are all mounted inside the electrical box. All these electrical components will be removed as an assembly when the box is removed. 16. Disconnect the White/Black. Purple, Brown and White leads between the electrical box and the stator and trigger assembly. 17. Disconnectthewiring harness connector. 18. Locate the low oil warningmodule secured to the inside of the lower powerhead cover and disconnect the following leads: Tan, Purple, light Blue leads and a Black ground eyelet lead. 19. Remove the bolts securing the module to the cover and remove the module. 20. Remove the securinghardware and lift out the electrical box with all electrical components undisturbed. Step19 :r •. Fig. 1 Make sure to identify the fuel system and throttle control components on the portside of the engine-7D-125hp 21. Disconnect the Blue/White. Green/White and Red/Black leads at the trim switch located on the side ol the lower powerhead cover. 22. Remove the screws securingthe cover to the air box. 23. Removethe long bolts securing the carburetors to the intake manilold. The carburetors are held together asan assembly by the forward straps, throttle and choke linkageand fuel lines. 24. Disconnect the fuel supply line and the primerline, il equipped. 25. Disconnect the fuel line belween the enrichener valve and the lilting on the fuelbowl of the topcarburetor and the linebetween thevalve and lhe fitting at lhe base of lhe oil pump. 26. Liltoffall carburetors. asan assembly, with linkage and fuel lines between the carburetors slill intact 27. Disconnect lhe light Blue leads from lhe low oil sensor, located at the base ol the oiltank, at their quick disconnect fittings. If the oil tank conlains oil, make arrangemenls Ia plug the oil line once itis pulled free ol lhe filling, to prevent oil from spillinginto the lower powerhead cover. Snipthe tie wrap from the oil supply line, from the tank, at theoil injeclion pump. Ease the line free of lhelilting on the pump and lilt oul the oil lank. 28. Disconnecl lhe oil outlet line between the pump and the 2 psicheck valve next Ia the fuel pump. Remove I he attaching bolls and remove lhe oil pump from lhe powerhead. 29. Snip the liewraps around lhe inlet. oullel and pulse lines al lhe fuel pump. Remove the Ptlillips head screws securingthe pump to the powerhead. lit\ oft the pump. 30. Remove lhe lop bolt securing the barrelretainer over the control cable barrels. SWing the retainer down to clear both barrels. 31. Remove the locknuts and washers securing the throttle and shift cable ends Iathethrottle lever and shift actuator stud. Slide the cables and barrels away from the barrel receplacles cast into the block and lift both cables clear. 32. Make a linal check to make sure no other leads or attachments will impede the removal ollhe powerhead. POWER HEAD 7-1 1 33. Remove the bolts securing the lowerpowerhead cover to the intermediale housing and removelhe cover. 34. Next. remove the bolts securing the powerhead to the inlermediale housing. 35. Remove the wing nuts securing the plastic flywheel cover to lhe powerhead. 36. Remove the plaslic cap from the end ollhe crankshaft. 37. Thread a lifting eyeonlo the end of the crankshaft as far as ilwill go. 38. Using a suilable hoist, lilt the powerhead assembly clear of the intermediate housing. 39. Allerlifting ofl the powerhead, remove all traces of the base gasket. 40. Moun! the powerhead onto sometype of sland, to facilitateeasy access toall parts. Never attempt to mount the powerhead in a stand sec..redin a vise . . such an atlempt will only lead to damage olthe powertlead and possible personal lnrury. 41. Remove lhe lifting eye from the crankshaft. 42. SniptheSta-strap from the tallle-tale hose at theaftcowling support bracket. 43. Remove the bolts securing the bracket to the powerhead. 44. Remove the bolts securing lhe ignition plale cover to the powerhead. 45. Disconnect thelarge Black lead from the cranking motor and the large Red lead lrom the cranking motor solenoid. 46. Unplug the power Irim fuse mounted on the cranking motor. 47. Loosen but do not remove the Phillips head screws on the clampsecuring the main harness to the powerhead. Slide the harness from its relaining clamp.48. Disconneclthethrollle cable from thethrottle lever. Disconnect the shift cable and theshill arm from the shiftbracket. Remove the bolts and the bracket from lhepowerhead. 49. Remove the bolts securing the powerhead to the intermediate housing. 50. Disconnect the oilinlet hose from the oil pumpand plug lhe line quickly to prevent oil from draining from lhe oil reservoir. 51. Remove lhe attaching hardware and lift the reservoir free of the powerhead. 52. Remove the wing nuts securing the plastic llywheel cover to the powerhead. 53. Remove the plastic cap lrom the end of the crankshaft. 54. Thread a lifting eye on the end ofthecrankshaft as far as it will go. Using a suilable hoist. lift the powerhead assembly clear of lhe intermediate hous· in g. 55. After lifting oHthe powerhead. remove all traces of the base gasket.56. Disconnectthe high tension leads lrom the spark plugs.Always use a pulling and twisling motion as a precaution against damaging the connection. 57. Remove the spark plugs.58. Mountthepowerhead onto sometype ofstand. to facilitate easy access to all parts. Never attempt Iamountthe powerhead in a stand secured ina vise. Such an attempt will only lead to damage of the powerhead and possible personal injury. Removethe lilting eye fromthe crankshaft. To install: 59. Thread a lilting eye onto theend of lhe crankshaft as far as it will go. For safely, check Ia be sure the lifting eye is properly installed. 60. Using a suitable hoist, lift the powerhead. Place a new gasketaround the powerhead studs and Jnlo position on the base of the intermediate housing. 61. Lubricate thedriveshaft splines with multipurpose lubricant. 62. Slowly lower the powerhead down onto the intermediale housing. It may be necessary to rotale the flywheel slightlyto index I he crankshaft splines with the driveshaft splines. 63. Once the splines index. lower the powerhead fully into place on the intermediate housing. 64. Install the lower cover around the intermediatehousing and secure the cover in place with the bolls. Tighlen the bolts to 80 inch lbs. (9Nm). 65. Disconnectthe hoist from the lifting eye and then remove lhe eye from the crankshaft. Install the plastic cap onto theend of the crankshaft. Install the llywheel cover and secure it in placewithllatwashers and wingnuls. 66. Secure lhe powerhead to lhe intermediate housing with the flat washers and locknuls. Tighten the locknuls instages Ia the specilied torque value. 67. On the75 and 90 hp models, 165 inch lbs. (19Nm}. Onthe 100, 115 & 125 hp models, 44 lt. lbs. (60Nm) 68. Disconnect the hoistIrom the lilting eye and then remove the eye Irom the crankshaft. 135-275 HP t See accompanying illustrations 1. Disconnect lhe battery cables from the baltery terminals. 2. Disconnect the fuel supply line from the fuel tank. 3. Unlatch and remove the topcowling or remove the front cover and swing the portand starboard cowling halves open. Lift the cowlings free of the rear support pins and set them aside. 7-12 POWER HEAD 4. Ifthemodel is equipped with a remote controlharnessretainer across the lower front cowfing, remove the screws and lift cot the retainer. Disconnectthe remote control cable harness from the sideof the powerhead. •Carefully observe the wiring and hose connections before proceeding. Because there are so many different outboards and the arrangement Is slightly different oneach, ills not possible to illustrate all of them. Even If they were shown, the reader would not be able to identify the outboard being serviced. Therefore, take time to make notes and tag the wiring and hoses. You may elect to follow the practice of many professional mechanics by taking aseriesof photographs of the powerhead, onefrom the top and a couple from the sides showing the wiring and hose arrangements along with other parts. 5. Disconnectthefollowing color coded wire leads fromthe plug-in connectors onthe starboard side of the poW8(head: Trim Indicator lead-Brown/While; TnmUp lead-Biue,/While; Trim Down lead-Green/White; Overheat Sensor lead-Tan: and 6. Disconnect the Blue, Green andBlack trimharness leadsfromthe up solenoid and the down solenoid,locatedonthe aft surface of the powerhead. Release the leads fromthe J-Ciip on the el 271. Install the screws and tighten securely. 7. The reed stop is not adjustable but can be checked. Replace the reed stop if the measurement Is not within the specification listed in the "Engine Rebuilding Specilications· chart. B. Reinstall the crankcase cover. 4-5 HP The reed valves are mounted to the crankease cover. Powerhead disassembly Is required to service the reeds. REMOVAL & INSTALLATION Reedval..e Reedvallle J·open closed OOS78GOI Fig. 2 Reed valves allow the air/fuel mixture from the carburetor to enter the crankcase, but not exit. They are in essence, one way check valves • See Figures 3 and4 1. Remove the crankcase cover. ' ·-2. Remove the screws securing the reed stop and reed petals to the crankcase cover. 3. Remove the reed stop and reed petals. Discard the reed petals. Toinstall: 4. Clean and inspect the crankcase cover and reed slop. Check lor indentation (wear) on the face of the seat area in the crankcase cover. II thereeds have worn indentations in the seat, the cylinder block and crankcase cover must bereplaced. 5. Install a new reed petal assembly into the crankcase cover. Place the reed stop over the reed petals. 035nl>12 Fig.3 Check the reed stop opening by measuring from the inside edge of the reed slop to the surface of the closed reed petal- 2.5-5hp Fig.4 Reeds mounted on the crankcase cover-2.!t-5hp • See Figures 3 and4 1. Remove the crankcase cover. 2. Remove the screws securing the reed stop and reed petals to the crankcase cover. 3. Remove the reed stop and reed petals. Discard the reed petals. 4. Thoroughly clean the reed block assembly in clean sotvent. 5. Check lor excessive wear (indentations), cracks orgrooves in the seal area of the reed block. Replace the reed block i! any damage is noted. 6. Check the reed petals for cracks, chips or evidence of fatigue. Replace the reed petals or reed block assembly il any damage is noted. To install: 7. Install a new reed petal assembly into the crankcase cover. Place the reed slop over the reed petals. 8. Coat the threads of the reed valve screws with Loctile"' 271 . Install the screws and lighten securely. 9. Check the reed stop opening by measuring between the reed slop and the top of the closed reed. Carefully bend the reed stop to obtain the dimension specified in the "Engine Rebuilding Specifications" chart. ,..On 4 hp models, one reed stop is flat and holds that reed petal closed making it inoperative. 10. Reinstall the crankcase cover. 6-15 HP Two sets of reed petals are mounted to a single reed block assembly. Each set of petals teeds one cylinder. A rubber seal separates the petals. The reed block is the intake manifoldand the carburetor bolls directly tothe reed block. The reed block is serviceable and the rubber seal replaceable on models so equipped. The reed block ort1997-QO models is nubber coated and is serviced as an assembly. The rubber seal is not replaceable on 1997-oo models. The rubber coaled reed block will retrofit to earlier models. REMOVAL & INSTALLATION • See Figures 5 and 6 1. Remove the carburetor 2. Remove the bolts securing the reed block to the powerhead. 3. Carefully remove the reed block assembly from the powerhead. ,..Do not scratch, warp or gouge the reed block or crankcase cover. Damaging these components will result in vacuum leaks . 4. Remove all gasket material from the reed block and crankcase cover. 5. As required, remove and discard the rubber seal lrom the center ol lhe reed block assembly. 6. Thoroughly clean the reed block assembly in clean solvent. 7. Check for excessive wear (indentations), cracks or grooves in the seal area of the reed block. Replace the reed blockif any damage is noted. 8. Check the reed petals for cracks, chips or evidence of latigue. Replace the reed petals or reed block assembly if anydamage is noted. To install: ..-Installing a new rubber seal in the center of the reed block assembly, as reqUired. Use needle bearingassembly grease to hold the rubber sealin position. 10. Using a new gasket, install the reed block over the carburetor mounting studs and seat it against the crankcase cover. If arubber seal is used, make sure it does not slip out ofposition. 11. Install the screws and tighten evenly to 60 inch lbs. (7 Nm). 12. Check the maximum reed opening between the petals and the reed block mating surface. Replace the reeds or reed block assembly il lhe reeds are stuck to the block or stand open more than the maximum limit specified in the "Engine Rebuild- POWER HEAD 7-15 top ol lhe closed reed. Carefully bend the reed slop to obtain the dimension specified inthe "Engine Rebuilding Specifications• chart. 14. Install the carburetor. 20-25 HP Two sets ol reed petals are mounted to a single reed block assembly.Each set of petals leeds one cylinder. A rubber seal separates the petals. An intake manifold (carburetor adapter) bolls between the carburetor and reed block. ,.. These models do not have serviceable reed valves. The rubber center seal is not removable. The reed block is-replaced as an assembly if any defect is noted. REMOVAL & INSTALLATION • See Figures 5 and 6 1. Remove the carburetor. 2. Remove the bolts securing the intake manifold and reed block to the power head. 3. Carelully remove the intake manifold and reed block assembly !rom the powerhead. Do not scratch, warp or gouge the reed block. intake manifold or crankcase cover. Separate the reed block from the intake manifold. Remove all gasket material from the reed block. intake manifold and crankcase cover. 4. Thoroughly clean the reed block assembly inclean solvent. 5. Check for excessive wear (indentations).cracks or grooves inlhe seal area of the reed block. Replace the reed block if any damage is noted. 6. Check the reed petals for cracks, chips or evidence of fatigue. Replace the reed block assembly ifany damage is noted To install: 7. Using new gaskets, install the reed block and intake manilold over the carburetor mounting studs and seat them against the crankcasecover. 8. Install the screws andtighten evenly to 80 inch lbs. (9 Nm) on 1994-QO models and70 inch lbs. (8 Nm) on all others. 9. Check the maximum reed opening between the petals and the reed block mating surface. Replace the reed block assembly if the reeds are stuck to the block or stand open more than the maximum limit specilied in the "Engine Rebuilding Specifications" chart. 10. Install the carburetor. 30 and 40 HP (2-Cylinder) Two sets of reed valves are mounted to a reed plate on late models (serial # OG380075 and later) and directly to the intake manifold on early models. A reed stop is used on 30 hp models only. The reed valves are replaceable onearly model powerheads only. On late model powerheads, the reed valves are serviced with the reed plate assembly. REMOVAL & INSTALLATION • See Figures 7 and 8 1. Remove the carburetor. ;r ingSpecifications" chart. 2. Remove the bolls securing the intake manifold and/or reed block to the powerhead. 13. Check the reed stop openingby measuring between the reed slop and the OS191G02 Fig. 5 Checking the maximum reed opening between the petals and the reed block mating surtace-6-25hp r Reed stop opening ..191G03 Fig. 6 Check the reed stop opening by measuring between the reed stop and the top of the closed reed-6-25hp 05197004 Fig. 7 Early model powerheads use reed petals that are mounted to iniake manifold • . • 7-16 POWER HEAD ... 3. Carefully remove the intake manifold and reed block assembly from the powerhead. Do not scratch, warp or gouge the reed block, intake manifold or crankcase cover. Separate the reed block from the intake manifold. Remove all gasket material from the reed block, intake manifold and crankcase cover. 4. Thoroughly clean the reed block assembly in clean solvent. 5. Check lor excessive wear (indentations), cracks or grooves in the seat area of lhe reed block. Replace the reed block if any damage is noted. 6. Check the reed petals for cracks. chips or evidence of fatigue. Replace the reed block assembly if any damage is noted. ,..Do not remove the reed petals from the intake manifold or reed plate unless they are going to be replaced. To install: 7. Using new gaskets, install the reed block and/or intake manifold over the ca.rburetor mounting studs and seal them against the crankcase cover. 8. Install the screws and tighten evenly to 17 ft. lbs. (22 Nm) in a circular paltern, starting in the center and working outward. 9. Check the maximum reed opening between the petals and the reed block mating surface. Replace the reed block assembly if the reeds are stuck to the block or standopen more thanthe maximum limit specified in the "Engine Rebuilding Specilications" chart. 10. On models so equipped, check the reed slop opening by measuring between the reed stop and the top of the closed reed. Carelulfy bend the reedstop to obtain the dimension specified in the "Engine Rebuilding Specifications· chart. 11. To replace the reed petals, proceed as follows: a. On models with replaceable reed petals, bend the lock washer lock tabs awayfrom the scrP.''I heads. Remove the screws attaching the reed petals, retaining washer or reeo stop to the intake manifold. Discard the lock tab washer. b. Apply Loctite® 271 to the threads of the screws. Position the new reed petals, retainingwashers or reed stops and new lock lab washers on the intake manifold. Make sure all components are aligned with the alignment pins in the intake manifold. c. Tighten the screws to 60 inch lb. (7 Nm) and check the alignment of the screwhead to the lock tab washer. II necessary, continue to tighten up to a maximum oil 00 inch lbs. (11 Nm) to align the screw head with the lock tab washer. Bend the lock tab of each washer up against each screw head. 12. Install the carburetor. 40 HP (4-Cylinder) REMOVAL & INSTALLATION Fig. 9Check the maximum reed opening between the petals and the reed block mating surface-40hp (4-Cylinder) 03558(;35 Fig. 10Check the reed stop opening by measuring between the reed stop and the top of the closed reed -40hp ( 4-Cylinder) ,..Locating pins have been subjected to overheating (melted) will not properly position the reed petals and reed stops. This can adversely affect the starting, idle and overall engine operation. As necessary, replace the reed block. 4. Assemble the reed block halves and secure with the appropriate fasteners. 5. Check for excessive wear (indentations), cracks or grooves in the seat area of the reed block. Replace the reed block ifany damage is noted. 6. Check the reed petals for cracks, chips or evidence of fatigue. Replace the reed block assembly if any damage is noted. 7. Check the reed block labyrinth seal area (inside diameter) lor excessive wear. Replace the reed blocks as necessary. 8. Check the maximum reed opening between the petals and the reed block mating surlace. Replace the reeds or reed block assembly if the reeds are stuck tothe block or stand open morethan the maximum limit specified in the ·Engine Rebuild· ing Specifications·chart. 9. Check the reed stop opening by measuring between the reed stop and the top or the closed reed. Ca.refully bend the reed stop to obtain the dimension specified in the 'Engine Rebuilding Specifications· chart. 10. To replace the reeds, proceed as follows: a. Remove the reed retaining screw from each reed block half. then remove the reed stops and reed petals. Discard the reed petals. b. Reassemble the reed valve assembly by installing new reeds and the original reed stops onto the reed block locating pins. Apply Loctitee 271 to the retaining screws and tighten to 30 Inch lbs. (3 Nm). Recheck maximum reed opening and reed slop opening. 40 HP (3-Cylinder), 50 and 60 HP Asingle reed plate and single Intake manifold is used on 40-60 hp. The40 hp (3Cylinder) uses a reed stop on each reed plate. ** CAUTION Do not allow the internal bleed (recirculation) system check valves to tall out or become misplaced while the intake manifold is removed. 1. Intake manifold 2. Reed plate assembly 05197G05 Fig. 8 . . •whil.f late model powerheads use reed petals mounted to a reed block assembly • See Figures 9 and 10 1. These models use 2 reed block assemblies mounted to the crankshaft. The reed blocks also serve as crankshaft labyrinth seals. Disassembly ot the powerhead is necessary to remove the reed blocks. 2. Clean the reed block assemblies thoroughly in clean solvent 3. Check the condition of the locating pins in the reed block halves. 03668634 , REMOVAL & INSTALLATION • See Figure 11 1. Remove the carburetors. 2. .Remove the screws securing the intake manifold and reed plate to the powerhead. 3. Carefully remove the intake manifold and reed plate from the powerhead. Do not scratch. warp or gouge the reed plate, infake manifold or crankcase cover. 4. Separate the reed plate from the intake manifold. Remove all gasket material from the reed plate, intake manifold and crankcase cover. 5. Thoroughly clean the reed block assembly in clean solvent. 6. Check lor excessive wear (indentations), cracks or grooves in the seat area of the reed block. Replace the reed block if any damage is noted. 7. Check the reed petals for cracks, chips or evidence of fatigue. Replace the reed block assembly if any damage is noted. .-oo not remove the reed petals from the reed plate unless replacement is necessary. Always replace reed petals in complete sets. Never turn a reed over for reuse or attempt to straighten a damaged reed. To install: 8. Check the maximum reed opening between the petals and the reed block mating sur ace. Replace the reeds or reed block assembly ifthe reeds are stuck to the block or stand open more than the maximum limit specified in the "Engine Rebuilding Specifications" chart. 9. Check the reed stop opening by measuring between the reed stop and the top of the closed reed. Carefully bend the reed stop to obtain the dimension specified in the "Engine Rebuilding Specifications· chart. 10. To replace the reed petals, proceed as follows: a. Bend the lockwasher lock tabs away from the screw heads. Remove the screws attaching the reed petals, reed stop or retaining washer to the reed plate. Discard the lock lab washers. b. Apply Loctite4!> 271 to the threads or the screws. Position the new reed peta!s, the original reed stops or retaining washers and new lock tab washers on the intake manifold. Make sure all components are aligned with the alignment pins in the intake manifold. c. Tighten the screws to 60 inch fbs. (7 Nm) and check the alignment of the screw head to the lock tab washer. If necessary, continue to lighten to a maximum of 100 inch lbs. (11 Nm) to align the screw head with the lock tab washer. d. Bend the lock tab washer of each washer against each screw head. .-Make sure the gaskets are correctly orientated. The gaskets only fit correctly in one direction. 11. Using new gaskets, install the reed plate and intake manifold to the powerhead. Install the retaining screws finger tight. 12. Tighten the screws evenly to 18 ft. lbs. (24 Nm) in the correct sequence. 13. Install the carburetors. 0365SGJ6 Fig. 11 Check the maximum reed opening between the petals and the reed block mating surface-40hp (3-Cylinder), 5Q-125hp POWERHEAD 7-17 75-125 HP Multiple reed plates and intake manifolds are used on these powerheads. .-oo not allow the internal bleed (recirculation) system check valves to fall out or become misplaced while the intake manifolds are removed. REMOVAL & INSTALLATION • See Figure 11 1. Remove the carburetors. 2. Remove the screws securing the intake manifolds and reed plates to the powerhead. 3. As necessary,disconnect the fuel primer valve line from the balance tubes at the fuel primer valve. 4. Carefully remove the intake manifolds and reed plates from the powerhead . Do not scratch, warp or gouge the reed plate, intake manifold or crankcase cover. Separate the reed plates from !he intake manifolds. Remove all gasket material from the reed plates, intake manifolds and crankcase cover. 5. Thoroughly clean the reed block assembly in clean solvent. 6. Check for excessive wear (indentations}, cracks or grooves in the seat area of the reed block. Replace the reed block if any damage is noted. 7. Check the reed petals for cracks, chips or evidence or Replace the reed plates if any damage is noted. ,-oo not remove the reed petals from the reed plate unless replacement is necessary. Always replace reed petals In complete sets. Never turn a reed over for reuse or attempt to straighten a damaged reed. To Install: 8. Using new gaskets, install the reed plates and intake manifolds to the powerhead. Install the retaining screws finger tight. 9. Checkthe maximum reed opening between the petals and the reed block mating surface. Replace the reeds or reed block assembly if the reeds are stuck to the block or stand open more than the maximum limit specified in the "Engine Rebuilding Specifications"chart. 10. To replace the reed petals, proceed as follows: a. Bend the lockwasher lock tabs away from the screw heads. Remove the screws attaching the reed petals, reed stop or retaining washer to the reed plate. Discard the lock tab washers. b. Apply Loctitet> 271 to the threads of the screws. Position the new reed petals. the original reed stops or retaining washers and new lock tab washers on the intake manifold. Make sure all componentsare aligned with the alignment pins in the intake manifold. c. Tighten the screws to 80 inch lbs. (9Nm} and check the alignment or the screw head to the lock lab washer. If necessary, continue to tighten to a maximum of 100 inch lbs. (11 Nm) to align the screw head with the lock tab washer. d. Bend the lock tab washer of each washer against each screw head. 11. Tighten the intake manifold screws evenly to 18 ft. lbs. (24 Nm) in a crossing pattern (75-90 hp} or a circular pattern starting with the 2 middlescrews in each manifold (100-125 hp). As necessary, reconnect the fuel primer valve hose from the balance tubes to the fuel primer valve. Secure the connection using a new tie-strap clamp. 12. Install the carburetors. 135-250 HP The 135-250 hp(Carbureted and EFI) use a one-piece intake manifold with 6 reed valve blocks. Up to 1995serviceable reed blocks with tapered reed petals were used. Since 1996, all models have been equipped with rubber coated reed blocks and square-tipped reeds. Rubber coated reed blocks are only serviced as assemblies. REMOVAL & INSTALLATION • See Figures 12, 13 and 14 1. On carbureted models, remove the carburetors. On EFI models, remove the intake manifold. .-There are 20 screws on the intake manifold. Only 8 screws actually secure the Intake manifold to the crankcase cover. If you are unsure which screws to remove, simply remove all 20 screws. 2. Remove the screws securing the intake manifold assembly to the powerhead. 3. Matchmark all bleed lines and note their position and routing for ;nstallation reference. .. , 7-1 8 POWER HEAD 00738039 Fig. 12 Reed block housing bolt tightening sequence-135-200hp with vertical reeds .. Fig. 13 Reed block housing bolt tightening sequence-135-200hp with horizontal reeds t\l7311G•I Fig. 14 Reed block housing bolt tightening sequence-225hp with horizontal reeds 4. Disconnect all bleed lines from the Intakemanifold. 5. Carefully temove the Intake manifold assembly from the powerhead. Do not scratch, warp or goug.. theintake manifold or crankcase cover.6. If notalready removed, remove the screws securing the reed boxes Ia the Intake manifold. Separate the reed boxes from the intakemanifold. To Install: 7. Removeall gasketmaterial from lhe reed boxes. intake manifold and crankcase cover. 8. Clean\he gaslle\surtaces of\he reedboxes thoroughly. Wash the reed boxes, Intake manifold. reed mounting blocks andspacer plates(as equipped)in cleansolvent9. Inspectthe Intakemanifold,reed mounting blocks and spacer plates(as equipped) lor distortion, cranks. blocked passages and fittings. 10. Check the reedboxes fordistortion, cracks, deep grooves oranyotherdam­agethat may cause leakage.Replaceas necessary. 11. Check tor excessive y,-ear (indentations).cracks or grooves in the seat area of the reed boxes.Replace the reedbox assembly ilany damage is noted. Onrubber coated reed blocks, check for rubber delamination from the reed box casting. Replace anyreed box showing rubbar delamination. 12. Check the reedpetals forcracks, chrps or evidence ol fatigue.Replace the reed petals or reedboxassembly it any damage is noted. 13. Checkthe stand-open gap between the reed petals and the reed platemating surface. Replace the reed petals or reed box assembly il any are pretoaded (slick lightly tolhe reed plate) or stand open more than specified . 14. To replacethe reed petals on models wilh serviceable reeds, remove the screws attaching the reed petals andreed clamp plates to the reed box. Discard the reed petals. 15. To reinstall, apply Loctltet' 271 to the threads of the screws. Position the new reed petals and the reed retaining plates 16. Using a new gasket, install the reed boxes to the intake manifold. Install the 12 retaining screws (2 each reed box) linger-tight. 17. Verily that the gasket is properly positioned and that all holes align correctly. Tighten the 12 reed box retaining screws evenly to80-90 inch lbs. (9-10Nm). 18. Position the intake manifold against the crankcase cover and install the 8 relainingscrews.Tig..len the retaining screws evenly to 105 inch lbs.(12 Nm). 19. Reconnect allbleed lines to their original positions. 20. Installthe carburetors and/or induction manifold. 135-225 DFI Optimax The 135-225 OFf Oplimax intake manifolds are unique in thallhe electric oil pumpismounted directly to !he intakemanifold and an addilionalspacer (lubrica­tion) plate andgasketare used. The oilpump moves oilthrough the reed plate's machine11 channels to each cylinde(s reedbox area Whe[J removing the intake manifold, remember to disconnect the oil pump electrical connection and externaloil sup­ply and air compressor lubrication lines. REMOVAL & INSTALLATION 1. Remove lhe Induction manifold. 2. Disconnect and cap the air compressor lubrication line the oil supplyline and anybleed !lnesthat areInthe way. 3. Disconnect the oil pump harness from the oil pump. 4. Removethe screws securing theoilpump bracket to the powerhead. 5. Remove the screws securing the Intake manifold assembly to the powerhead. 6. Carefully removelheintake manilold assembly from thepowerhead. Do not scratch, warp or gouge the intake manifold or crankcase cover. ,..Internal recirculation valves are usedon this engine. The valves fit Into machined grooves onthe mating surface of the crankcase cover to Intake manifold. The valves areinstalled in rubber carriers. Do not lose ormisplace the check valves and carriers. 7. Remove the screws securing the oil pump to the intakemanifold. Remove the oilpump from the Intake manifold. 8. Remove the screws securing the reedboxes lothe space plate and Intake manilold Separate lhe reedboxes from lhe spacer piate.Separate the spacerplate from the Intake mamfold. Removeallgasket material fromthe reedboxes, spacer plate, oil pump, Intake manilold and crankcase cover.9. Clean and Inspectthe reed boxes and intake manifold. The reedboxes are nol serviceable. If any defectsare noted, replace the suspect reed box. Make sure all machinedpassages inthe inlakemanilold are dean. 10. Clean the gasllet surfaces of the reed boxes thoroughly.Wash the reed boxes, intakemanifold,need mounting blocks and spacer plates (as equipped) in cleansotvenl 11. Inspectthe intakemanifold. reed mounting blocks and spacer plates (as equipped) for distortion, cranks. blocked passages and fittings. 12. Check the reed boxes lor distortion, cracks, deep grooves orany otherdamage that may cause leakage. Replace as necessary. 13. Check for excessive wear (indentations), cracks or grooves in the seat area of the reed boxes.Replace the reed box assembly if any damage is noted. Onrubber coated reed blocks, check lor rubber delamination from the reed box casting. Replace anyreed box showing rubberdelamination. 14. Check the reed petals for cracks. chips or evidence of fatigue. Replace the reed petals or reed box assembly ifanydamage is noted. 15. Check the maximum reed opening gap between the reed petals and the reed plate mating surface. Replace the reed petals or reed box assembly II any are preloaded (sUck lightly to lhe reed plate) or stand open more than specilied .16. Usingnew gaskets. install the reed boxes to the spacer plateand Intake manifold. Coat the threads ol the reed box retainingscrewswllh loctite.'. 271. Install the retainingscrewsfinger tight. 17. Verily that the gaskets and spacer plate areproperlypositioned and that an holes are aligned. lighten the reed box retainingscrews evenly to 90 inchfbs. (10 Nm). 18. Using a new gasket, instillthe oilpumpand oil pumpbracket tothe intake manifoldassembly. Install and tighten the screws securely. 19. Position the intakemanifold assembly against the crankcase coverand Install the retainingscsews. lightenthe retainingscrewsevenly to 100 inchlbs. (11 Nm). 20. Install the screwssecuring\he oilpump bracket to thepowl!lhead. Tighten thescrews securely. 21. Reconnect theoilpumpelectrical connector. oil supply line and air compres­sorlubricalion line. Secure the line connedions with newlie straps.22. Install the inductionmanifold. 23. PtJrge the electric oil pump. 275 HP The275hp models are unique In that they use a separate intakemanilold for each - cylinder. The intake manllolds and gaskets are different from port io starboard. Each intake manllold contains 2 reed valve block assemblies. The reed valve blocks are onlyserviced as assemblies. POWER HEAD 7-19 REMOVAL & INSTALLATION , , t See Figure 15 1. Remove the carburetors. 2.•Remove the screws securing the fuel primer valve bracket to the lower intake manifolds. lay the fuel primer valve and bracket to one side. 3. Note the position and routing of the balance hoses and fuel primer lines to and from each in take manifold. Disconnect and cap the balance hoses. bleed lines and fuel primer lines !rom the intake manifolds. 4. Remove the screws securing each intake manifold assembly to the powerhead. Note the position ol lhe control cable support bracket mounted to the bottom of the port lower intake manifold. 5. Carefully remove each intake manifold assembly from the powerhead. Do not scratch, warp or gouge any intake manifold or the crankcase cover. 6. Remove the lower screws securing the reed mounting block to each intake manifold. 7. Remove the upper reed box screws securing the reed mounting block and upper reed block to each intake manifold. Separate each manifold assembly's reed mounting block upper reed box and inlake manifold from each other. 8. Remove the screws securing the lower reed box to each reed mounting block. Separate each lower ..eed box I rom each reed mounting block. 9. Remove all gasket material from the reed boxes, reed mounting blocks. intake manifolds and crankcase cover. To install: 10. Clean and inspect the reed boxes and in take manifolds. The reed boxes are not serviceable. II any defects are noted, replace the suspect reed box. Make sure all machined passages and fittings in the intake manifold are clean. 11. Clean the gasket surfaces ot the reed boxes thoroughly. Wash the reed boxes, intake manifold, reed mounting blocks and spacer plates (as equipped) in clean solvent. 12. Inspect the inlake manifold, reed mounling blocks and spacer plates (as equipped) for distortion. cranks. blocked passages and fittings. 13. Check the reed boxes for distortion. cracks. deep grooves or any other damage that may cause leakage. Replace as necessary. 14. Check lor excessive wear (indentations), cracks or grooves in the seat area of the reed boxes. Replace the reed box assembly if any damage is noted. On rubber coated reed blocks, check tor wbber delamination from the reed box casting. Replace any reed box showing rubber delamination. 15. Check the reed petals for cracks, chips or evidence of fatigue. Replace the reed petals or reed box assembly if any damage is noted. 16. Check the maximum reed open gap between the reed petals and the reed plate mating surface. Replace the reed pelals or reed box assembly if any are preloaded (slick tightly to the reed plate) or stand open more than specified . 17. Check the reed stop opening by measuring from the inside edge of the reed stop to the surface of the closed reed petal. A drill bit of the specified dimension should just fit between the widest gap of the reed slop and the reed petal. Replace the reed box assembly it I he measurement is not within specification . 18. To replace the reed petals on models with serviceable reeds, proceed as follows: a. Remove the screws attaching the reed petals and reed clamp plates to the reed box. Discard the reed petals. POWERHEAD RECONDITIONING Determining Powerhead Condition Anything that generales heat and/or friclion will eventually burn or wear out (for example, a fight bulb generates heat. therefore its life span is limited). With this in mind, a running powerhead generates tremendous amounts of both; friction is encountered by the moving and rotating parts inside the powerhead and heal is created by friction and combustion of the fuel. However, the powerhead has systems designed to help reduce the effects of heat and friction and provide added longevity. The oil injection system combines oil with the fuel to reduce the amount of friction encountered by the moving parts inside the powerhead. while the cooling system reduces heat created by friction and combustion. If either system is not maintained, a break-down will be inevitable. Therefore, you can see how regular maintenance can affect the service lite of your powerhead. There are a number of methods for evaluating the condition of your powerhead. A secondary compression test can reveal the condition ol your pistons, piston rings, cylinder bores and head gaskel(s). A primary compression test can determine the condition of all engine seals and gaskets. Because the 2-stroke powerhead is a pump, the crankcase must be sealed against pressure created on the down stroke of the piston and vacuum created when the piston moves toward top dead center. If there are air leaks into the crankcase. insulficient fuel will be brought into the b. Apply Loctitee 271 to the threads of the screws. Position the new reed petals and the reed retaining plates 19. Using new gaskets, install the lower reed boxes to the reed mounting blocks. Coat the threads of the reed box retaining screws with loctile8 271. Install and evenly lighten the screws to 60 inch Ills. (7 Nm). 20. Using new gaskets install the reed mounting blocks to the intake manifolds. Coat the threads of the reed block lower retaining screws with loctite"' 271. 1nstall the screws finger-tight. 21. Using new gaskets install the upper reed boxes to the reed mounting block and intake manifold assemblies. Coat the threads of the reed box retaining screws with loctile"' 271. Install the screws linger-tight. 22. Check the alignment of the reed boxes. reed mounting blocks and intake manifolds. Make sure all holes are aligned. Tighten the upper screws and lower screws on each intake manifold assembly evenly to 60 inch lbs. (7 Nm). 23. Install the intake manifold assemblies to the crankcase cover. Coat the threads of the retaining screws with Loctile& 271 . Install the retaining screws (4 each intake manifold) finger-tight. 24. Verily that the intake manifolds are correctly positioned and that control cable bracket is installed on the bottom of the lower port manifold. Tighten each manifold's 4 retaining screws evenly to 150 inch lbs. (17 Nm). 25. Reconnect the balance hose. bleed lines and fuel primer lines to the intake manifolds.26. Position the fuel primer valve bracket on the lower port intake manifolds. Coat the threads of the retaining screws with loctite• 271. Install and tighten the screws to 60 inch lbs. (7 Nm). 27. Install the carburetors. 28. Reconnect the negative battery cable. crankcase and into the cylinder for normal combustion. Information on compression testing can be found In the "Maintenance and Tune-up· section. Buy or_Rebuild? • See Figures 16 and 17 Now that you have determined that your powerhead is worn out, you must make some decisions. The question of whether or not a powerhead is worth rebuilding is largely a subjective matter and one of personal worth. Is the powerhead a popular one or is it an obsolete model? Are parts available? Is the outboard it's being put into worth keeping? Would it be less expensive to buy a new powerhead. have your powerhead rebuilt by a pro, rebuild it yoursell or buy a used powerhead? Or would it be simpler and less expensive to buy another outboard? If you have considered all these matters and more and have still decided to rebuild the powerhead. then It is time to decide how you will rebuild it. ,. The editors at Seloc• feel that most powerhead machining should be performed by a professional machine shop. Don't think of it as wasting money, rather, as insurance that the job has been done right the first Reed stop 03138G42 Fig. 15 The 275hp models are unique in that they use a separate intake manifold for each cylinder r' · 7-20 POWER HEAD Fig.16 The question of whether or not a powerhead is worth rebuilding is largely a subjective matter and one of personal worth. This powerhead is not worth much in Its present condition 050031'1)1 Fig. 17 A burned piston like this one will Fig. 18 Much of the assembly work (crankshaft, bearings, pistons, connecting rods and other components) is well within the scope of the average do-it-yourself mechanic's tools and abilities be replaced during an overhaul. The condition which caused the hole in the top of the piston must be identified and corrected or the same thing will happen again lime. There are mA"ny expensive and specialized tools required to perform such tasks as boring and honing apowerhead. Even inspecting the partsrequires expensive micrometers and gauges to properly measure wearand clearances. Also, amachine shop candeliver to you clean and ready to assemble parts, saving you time and aggravation. Your maximumsavings will come from performing the removal, disassembly, assemblyand installation of the powerhead and purchasing or renting onlythe tools required to perform the above tasks. Depending on the particularcircumstances, you may save 40 to60 percent of the cost doing these yourself. Acomplete rebuild or overhaul of a powerhead involves replacing or reconditioning all of the moving parts(pistons, rods, crankshaft, etc.} withnew or remanufactured ones and machining the non-moving wearingsurfaces of the block and heads. Unfortunately, this may not be cost effective. For instance, your crankshaft may have been damaged or worn but it can be machined for a minimal fee. So, as you can see. you can replace everything inside the powerhead but, it is wiser to replace only those parts which are really needed and, ifpossible, repair the more expensive ones. Powerhead Overhaul Tips • See Figure 18 Mostpowerhead overhaul procedures are fairly standard. In addition to specific parts replacement procedures and specifications for your individual powerhead, this section isalso a guide toacceptable rebuilding procedures. Examples of standard rebuilding practice are given and should be used along with specific details concerning your particular powerhead. Competent and accurate machine shopservices will ensure maximum performance, reliability and powerhead Iif e. In most instances it is more profitable forthe do-it-yourself mechanic to remove,clean and inspect the component. buy the necessary partsand deliver these to a shop foractual machine work. Much of the assemllly work (crankshaft, bearings, pistons, connecting rods and other components) iswell within the scope of thedo-it-yoursell mechanic's tools and abilities. You will have to decide for yourself the depth of involvement you desire in a powerhead repair or rebuild. TOOLS The tools required lor a powerhead overhaul or parts replacement will dependon the depth of your involvement. With a few exceptions, they wilt be the tools found in an average do ityourselfer's tool kit More in-depth work will require some or all of thefollowing: • Adial indicator (reading in thousandths) mounted on auniversalbase • Micrometers and telescopegauges • Jaw and screw-type pullers • Scraper • Ring groove cleaner • Piston ring expanderand compressor• Ridge reamer • Cylinder hone or glazebreaker • Plastigage3 • Powerhead stand The use of most of these tools is illustrated in this section. Many can be rented lor a one-time use from a local parts store or tool supply house. Occasionally, the use ol special tools is necessary. See the information on Special Tools and the Safety Notice in thefront ol this book before substituting another tool. CAUTIONS Aluminum is extremely popular lor use in powerheads, due to its low weight. Observe the following precautions when handling aluminum parts: • Neverhot lank aluminum parts, the caustic hot lank solution will eat the aluminum • Remove allaluminum parts (identification tag, etc.) from powerhead parts prior to hot tanking • Always coal threads lightlywith oil or anti-seizecompounds before installation, to prevent seizure • Never overtighten !lofts or sparkplugsespecially in aluminum threads When assembling the powerhead, any parts that will be exposed to frictional contact must be prelulled to provide lubrication at initial start-up. Any product specifically formulated lor this purpose can be used. When semi-permanent(locked but removable) installation of bolts ornuts is desired.threads should be cleaned and coated with Loctite., or another similar, commercial non-hardening sealant. CLEANING Before the powerhead and its components are inspected, they must be thoroughly cleaned.You will needto remove any varnish, oil sludge and/or carbon deposits from all of the components to insure an accurate inspection. A crack in the block or cylinder head can easilybecome overlooked if hidden oy a layerof sludge or carbon. Most of thecleaning process can be carried out with common hand toolsand readily available solvents or solutions. Carbon deposits can bechipped away using a hammer and a hard wooden chisel. Old gasket material and varnishorsludge can usually be removed using a scraper and/or cleaning solvent Extremely stubborn deposits mayrequire the useof apower drill with awire brush. Always followany safety recommendations given by the manufacturer ollhetool and/or solvent You should always wear eye protection during any cleaning process involving scraping, chipping orspraying of solvents. ,..If using awire brush, useextremecarearound any critical machined surfaces (such as the gasket surfaces, bearing saddles, cylinder bores, etc.). Use of a wire brush is not recommended onany aluminum components. An alternative lo the mess and hassleof cteaning the parts yourself is to drop them off at a local machine shop. They will, more than likely, have the necessary equipment to properly clean all ol the parts for a nominal lee. ** CAUTION Always wear eye protection during any cleaning proces.s involving scraping, chipping or spraying ofsolvents. , ,_ Remove any plugs or pressed-in bearings and carefully wash and degrease all of the powerhead components including the fasteners and bolts. Small parts should be placed in a metal basket and allowed to soak. Use pipe cleaner type brushes and clean all passageways in the components. Use a ring expander to remove the rings from the pistons. Clean the piston ring grooves with a ring groove cleaner or a piece ol broken ring. Scrape the carbOn oil ol the top of the piston. You should never use a wire brush on the pistons. After preparing all of the piston assemblies in this manner, wash and degrease them again. REPAIRING DAMAGED THREADS • See Figures 19, 20, 21, 22 and 23 Several methods of repairing damaged threads are available. Heli-Coil"', Keenserts• and Microdot0 are among the most widely used. All involve basically the same principle, drilling out stripped threads, tapping the hole and installing a prewound insert, making welding, plugging and oversize fasteners unnecessary. Two types of thread repair inserts are usually supplied: a standard type for most inch coarse, inch line. metric course and metric line thread sizes and a spark lug type to fit most spark plug port sizes. Consult the individual tool manufacturer's catalog to determine exact applications. Typical thread repair kits will contain a selection of prewound threaded inserts, a t.. (corresponding to the outside diameter threads of the insert) and an installation tobl. Spark plug inserts usually differ because they require a tap equipped with pilot threads and a combined reamer/tap section. Most manufacturers also supply blister-packed thread repair inserts separately in addition to a master kit containing a variety of taps and inserts plus installation tools. Before attempting to repair a threaded hole. remove any snapped, broken or damaged bolts or studs. Penetrating oil can be used to free frozen threads. The offending BOLT SCREW I . THREADED INSERT - DAMAGED THREADS POWER HEAD 7-21 item can usually be removed with locking pliers or using a screw/stud extractor. After the hole is clear, the thread can be repaired, as shown in the series of accompanying illustrations and in the kit manufacturer's instructions. Powerhead Preparation • See Figure 24 To properly rebuild a powerhead, you must first remove it from the outboard, then disassemble and inspect it. Ideally you should place your powerhead on a stand. This attords you the best access to the components. Follow the manufacturer's directions lor using the stand with your particular iiowerllead. Now that you have the powerhead on a stand, it's time to strip It of all but the necessary components. Before you start disassembling the powerhead, you may want to take a moment todraw some pictures, fabricate some labels or get some containers to mark and hold the various components and lhe bolts and/or studs which fasten them. Modern day powerheads use a lot of little brackets and clips which hold wiring harnesses and such and these holders are often mounted on studs and/or bolls that can be easily mixed up. The manufacturer spent a lot of time and money designing your outboard and they wouldn't have wasted any of it by haphazardly placing brackets, clips or fasteners. II irs present when you disassemble it, put it back when you assemble it, you will regret not remembering that little bracket which holds a wire harness out of the path of a rotating part. You should begin by unbolting any accessories attached to the powerhead. Remove any covers remaining on the powerhead. The idea is to reduce the powerhead to the bare necessities (cylinder head(s), cylinder block, crankshaft, pistons and connecting rods), plus any other 'in block' components. 1CCS30!0 1CCSJ039 Fig. 19 Damaged bolt hole threads can be replaced with thread repair inserts Fig. 20Standard thread repair insert (lett) and a spark plug thread insert TCCSJI>\1 Fig. 21 Drill out the damaged threads with the specified size bit. Be sure to drill completely through the hole or to the bottom of a blind hole 1CCS1042 Fig. 22 Using the kit, tap the hole to receive the thread insert. Keep the tap well oiled and back it out frequently to avoid clogging the threads TCCS304.1 Fig. 23 Screw the insert onto the installer tool until the tang engages the slot. Thread the Insert into the hole until it is Y.-%tum below the top surface, then remove the tool and break of the tang using a punch 0373SP08 Fig. 24 Large powerheads will require the installation of a lifting eye and the use of an engine hoist to remove them from the outboard 7-22 POWERHEAD Cylinder Block and Head GENERAL INFORMATION t.See Figures 25 thru 35 . The cylinder-block is made of aluminum and may have cast-in iron cylinder liners. It !s the mat or part of the powerhead and care must be given tothis part when service work IS pertormed. Mishandling orimproper service procedures pertormed on thisassembly may make scrap_outofan otherwise good casting. The cylinderassembly casting and other maJOr castmgs on the outboard are expensive and need tobe cared for accordingly. There are three parts to the cylinder assembly, the cylinder block, the crankcase half and on some powerheads and separate the cylinderhead. The cylinder block and crankcasehalf are married together and line bored to receive the crankshaft bearings, reed blocks and on some powerheads sealing rings. Alter this operation they are treatedas one casting. .. Remember that anything done to the mating surfaces during service work will change the inner bore diameter for the main bearings, reed blocks and sealing rings and possibly prevent the block and crankcase mating surfaces from sealing. The only service work allowed on the mating surface is a lapping operation to remove nicks from the service. Carefully guard this surface when otherservice work is being performed. The different sealing materials used to seal the mating surfaces are sealing strips, sealing compound and Loctilee. Sincethe 2-strokepowerhead operates like a pump with one inlet and one outlet for each cylinder,special sealing features mustbe designed into the cylinder assemblyto seal each individual cylinder in a_!]lulli-cylinder powerhead. Each inlet manifold must !Je completelysealed both for vacuum and pressure. One way of doing this .. . 1nternally IS wrth a labynnlh seal, wh1ch IS located between two adjacent cylinders next to the crankshaft. It may be of aluminum or brass, formed in the assembly and machined with small circular grooves running very close toa machined area on the crankshaft. The tolerance is so close that fuel residue puddling in the seal effectively 0500.. Fig.27 . . . and cylinder head make up the major components of the cylinder assembly lll57lll'31 Fig. 30 On smaller powerheads, neoprene seals are installed to seal the ends of the cylinder block assembly around the crankshaft Fig.33 . . are installed at both the ' '· Fig. 25 The cylinder block . . crankcase half . 050011'31 050G7P16 Fig.29 The cylinder block and crankcase Fig. 28 In this cylinder, an exhaust port half are machined to fit together perfectly. can be seen above the level of the piston. The inlet port is on the opposite side of They provide a cradle lor the spinning the cylinder wall, below the piston crankshaft End cap llll':!8P44 lll73111'41 Fig. 31 On larger powerheads, end caps which use seals . . . :r ,.'· POWER HEAD 7-23 Lower end cap 037381'38 Fig. 35 Sealing rings are also installed 050071'63 Fig. 36 Every time the cylinder head Is removed, the cylinder head and cylinder block deck should be checked for warping using a straight edge and a feeler gauge 03T.l!I'S1 Fig. 34 . . . and lower ends of the cylinder block assembly . . . into grooves in the crankshaft. When the crankshaft is installed, the sealing rings mate up to and seal against the web In the cylinder block crankcase halves completes the seal belweeiJthe cylinder block and crankcase halves against the crankshaft. Crankcase pressures are therefore retained to each individual cylinder. No repair of the labyrinth seal is made. If damage has occurred to the seal, the main bearings have allowed the crankshaft to run out and rub. Another method of internal sealing belween the crankcases is with seal rings. These rings are installed in grooves in the crankshaft. When the crankshaft is installed, the sealing rings mate up to and seal against the web in the cylinder block crankcase halves and crankshaft. Sealing rings of different thickness are available for service work. The side tolerance is close. so puddled fuel residue wi II eflectively complete the seal between crankcases and crankshaft. To seal the ends of the cylinder assembly around the crankshaft, 0-rings are installed around the end caps and neoprene seals are installed inside the cap and seal against the crankshaft INSPECTION t See Figures 36, 37 and 38 Everytime the cylinder head is removed, the cylinder head and cylinder block deck should be checked for warping. Do this with a straight edge or a surface block. If the cylinder head or cylinder block deck are warped, the surface should be machined flat by a competent machine shop. Minor warpage may be cured by using emery paper in aligure eighl motion on a surface block until the surface is true. Inspect the cylinder head and cylinder block for cracks and damage to the bolt holes caused by galvanic corrosion. On models which do not use a cylinder head, check the cylinder dome for holes or cracks caused by overheating and pre-ignition. The spark plug threads may also be damaged by overtorquing the spark plug. Quite often the small bolts around the cylinder block sealing area are seized by corrosion. If white powder is evident around the bolts, stop. Galvanic corrosion is probably seizing the shank of the bolt and possibly the threads as well. Putting a wrench on them may just !wist the head oil, creating one big mess. Know the strength of the bolt and stop before it breaks. If it does break, don't reach for an easy out, it won't work. A good way to service 'these seiied bolts is with localized heat (from a heat gun, not a Iorch) and a good penetrating oil. Heat the aluminum casting, not the bolt. This releases the bolt from the corrosive grip by creating clearance between the bolt, the corrosion and the aluminum casting. Be careful because too much heal will melt the casting. Many bolts can be released in this way, preventing drilling out the total bolt and heli-Coiling the hole or lapping the hole for an oversize boll. To help prevent bolts from seizing due to corrosion, coat threads with a good anti-seize compound. Cylinder Bores GENERAL INFORMATION The purpose ol the cylinder bore is to help lock in combustion gases, provide a guided path lor the piston to travel within, provide a lubricated surface for the piston rings to seal against and transfer heat to the cooling system. These functions are carried out through all engine speeds. To function properly the cylinder has to have a true machined surface and must have the proper finish installed on it to retain lubricant. INSPECTION t See Figures 39 and 40 The roundness of the cylinder diameter and the straightness of the cylinder wall should be inspected carefully. Micrometer readings should be taken at several points to determine the cylinder condition. Start at the bottom using an outside micrometer or dial bore gauge. By starling at the bottom, below the area of ring travel, cylinder bore diameter can be determined and a determination can be made if the powerhead is standard or has been bored oversize. Take the second measurement straight up from the first in the area of the ports and note that the cylinder is larger here. This is the area where the rings ride and It has worn slightly. Take the third measurement within a half inch of the top of lhe cylinder, straight up from where the second measurement was taken. These three measurements should be repeated with the measuring instrument turned 90° clockwise. Fig. 37 When inspecting components for warping, check in multiple directions 050DIP87 Fig. 38 To help prevent bolts from seizing due to corrosion, coat threads with a good antiseize compound. Fig. 39 The roundness of the cylinder diameter and the straightness ol the cylin· der wall should be inspected using a dial bore gauge 7-24 POWER HEAD Fig. 40 Readings should be taken at sev· Fig. 41 A hole placed in the side of the Fig. 42 The piston has machined grooves eral points to determine the cylinder con· piston, commonly referred to as the piston in which the rings are installed. They are dition. Start at the bottom and work your boss, is used to mount the piston to the carried along with the piston as II travels way to the top piston pin up and down the cylinder wall After the readings are taken, you will have enough information to access the cylln· der condition. This wi.. tell you If the rings can simply be replaced or li the cylinder will need to be overbored. Whlle measuring the cylinder, you should also be noting If there is a cross-hatched patlern on lhe cylinder walls. Also note any scuffing or deep scratches. REFJNJSHJNG II the cylinder is out or round, worn beyond specification. scored or deeply scratched. reboring will be necessary. II the cylinder is within specilicallon, it can be deglazed with a llex hone and new rings installed. ,-some cylinders are chrome plated and require special service proce· dures. Consult a qualified machine shop when dealing with chrome plated cylinders. Almost all engine block refinishing must be performed by a machine shop. li the cylinders are not to be rebored, then the cylinder glaze can be removed wlth a ball hone_ When removing cylinder glaze wilh a ball hone, use a lighl or penetrallng type oil to lubricate the hone. Do not allow the honeto run dry as this may cause exces­srve scoring or the cylinder boresand wear on the hone. II new pistons are required. they will need to be installed to theconnecting rods. Thisshould be performed by a machineshopas the pistons must be installed in the correct relationship tothe rod or engine damage can occur. When degtazing, il ls important to retain the tactory surface ot the cylinder wall. The cross-hatched patter on the cylinder wall Is used to retain oil and seal the rings. As the piston rings move up and down the wall, a glaze develops. The hone Is used to remove this glaze and reestablish the basket weave pattern. The paMern and the tinish is has a satin look and makes an excellent surface for good retention ol 2stroke oil on the cylinder wall. There is nothing magic about the crosshatch angle but there should beone similar to what the ractory used. (approximately 20-40"). Too steep an angle or too flat a pattern is not acceptable and asit is not good for ring sealing. Since the hone reverses as it is being pushed down and pulled up the cylinder wall, many different angles are created. Multiple criss-Crossing angles rue thesecret l01 longevity ol the cylinder and the rings. The pattern allows 2-stroke oil to llmv under thepiston ringbearing surface and prevents ametal-lo·metal contact between the cylinder wall and piston ring. The satin finish Is necessary to prevent early break-in scuffing and to seat the ring correctly. Mer the cylinder hone operation has been completed. one very Important job remains. The grit that was developed In the machining process must be thoroughly cleaned up. Grit lett in the powerhead will find its way into the bearings and piston rings and become embedded Into the piston skirts, ellectivety grinding away at t..ese precision parts. Relate this to emery paper applied to a piece or steel or steel agarnst a grinding stone. The effect is removal ol material !rom the steel. Grit left in Ihe pow· erhead will damage internal components in a very short time. Wiping down the cylinder bores with an oil or solvent soaked rag does not remove grilCleaning must be thorough so that all abrasive grit material has been removed !rom lhe cylinder s. It is Important to usea scrub brush and plenly of soapy wale.. Remember that aluminllm is not safe with all cleaning compounds. so use a mild dish washing detergent thai is designed to remove grease. After the cylinder is thought to be clean. use a White paper towel to test the cylinder. Rub the paper towel up and down on the cylinder and took lor the presence of gray color on the towel. The gray color is gril Re-scrub the cylinder until il ls perfectly clean and passes the paper towel test. When the cytlnder passes the test. immediately coat It with 2·stroke oil to prevent rust from forming. •Rust forms very quickly on clean, oil free metal. Immediately coat all clean metal with 2·stroke oil to prevent the formation of rust. Pistons GENERAL INFORMATION • See Figures 41, 42, 43 and 44 Piston rue the moveable end ol a cylinder. The cylinder bore provides a guided path tor the piston allowing a small clearance between the piston skirt and cylinder wall. This clearance allows lor piston expansion and controls piston rock within the cylinder. . . •Modem piston design Is such that the head of the prston d1rects incommg fuel toward the top of the cylinder and outgoing exhaust to the exhaust port in the cylinder wall. This design Is called adeflector type piston head. The dellector dome deflects the incoming fuel upward to the spark plug end of the cylinder. partially cooling the cylinder and spark plug tip. It also purges the spent gases from the cylinder. In essence, the Incomingfuel charge ischasing out the exhaust gases trom thecylinder. Not all piston designs are ol the dellectOI head type. Other pistons have a small convex crown on the piston head. In this case. port design aids in direcllng the incoming tuel upward. The piston head bears the brunt ol the combustion Ioree and heal Most ol the heat is transferred !rom the piston head through the rings to the cylinder wall and then on lo lhe cooling system. The piston design can be round, cam ground or barrel shaped. The cam ground design allows tor expansion of the piston in a controlled manner. As the piston heats up, expansion take place and the piston moves out along the piston pin becoming more round as it warms up. Barrel shaped pistons rock very slightly In Ihe bore which helps to keep the rings tree. The piston has machined ring grooves in which the rings are installed. They. are carried along with the piston as it travels up and down the cylinder wall. There IS one smallpin in each ring groove to prevent the ring from rotating. The piston skirt is the bearing ruea for thrust and rides on the cylinderwaUoilfilm. The side thrust ol the piston is dependent upon piston pin location. li the pin is in the center of.lhe piston. then there will be more thrust. If the pin is oHsel a few thousandths of an rnch from lhe center of lhe piston. there will be less lhrusl A used piston will have one side of the piston skirt show more signs or wear than the opposite side. The side showing wear is the major thrust side. Thrust is caused by the pendulum action of the rod following the crankshaft rota· lion. which pulls the rod out lrom under the piston. The combustion pressure therelore pushes and thrusts Ihe piston skirt against the cylinder wall. Some heat Is also transferred at this point. The other skirt receives only minor pressure. Some pistons. have small grooves circling the skirts to retain oil in the critical area between the sk1rt and the cylinder wall. INSPECTION • See Figures 45 and 46 The piston needs to be inspected for damage. Check the head lor erosion caused - by excessive heat. lean mixtures and out ol specification timing/synchronization. Examine the ring land area to see if it is Hat and not rounded over. Also toOk lor burned through areas caused by preignition. Check the skirt tor scoring caused by a :r '· POWER HEAD 7-25 Fig. 43 There is one small pin in each ring groove to prevent the ring from rotating 05007G2W Fig. 44 Piston diameter should be measured at a specific position on the piston which the manufacturer will specify Fig. 45 This piston is severely scored from lack of lubrication and should not be reused break through of the oil film. excessive cylinder wall temperatures, incorrect timing/synchronization or inadequate lubrication. To measure the piston dtameter, place an outside micrometer on the piston skirt at the specified location. All pistons in a given powerhead should read the same. Check the specifications for placement of the micrometer when measuring pistons. Generally there Is a specific place on the piston. This is especially true of barrel shaped pistons that are larger in the middle than they are at lhe top and bottom. If the piston looks reasonably good after cleaning, take a close look at the ring lands. Wear may develop on the bottom of the ring lands. This wear is usually uneven. causing the ring to push on the higher areas and loads the ring unevenly when inertia is the greatest. Such uneven support ol the ring will cause ring breakage and the piston will need to be replaced. When installing a new ring in the groove, measure the ring side clearance against specification. Also check the see il the ring pins are there and that they have not loosened. Measure the skirt to see il the piston is collapsed. Fig. 46 Pistons should be installed with the arrow facing the exhaust port Piston Pins GENERAL INFORMATION • See Figures 47, 48 and 49 A hole placed in the side of the piston. commonly referred to as the piston boss, is used to mount the piston to the piston pin. The combustion pressure is transferred to the piston pin and connecting rod bearing, then on to the crankshaft where it is converted to rotary motion. The pin is fihed to the piston bosses. The piston pin is the inner bearing race for the bearing mounted in the small end of the connecting rod. This transfers the combustion pressures into the connecting rod and allows the rod to swing with a pendulum-like action. Piston pins are secured into both piston bosses. All have retainers and in addition some use a press fit to secure the pin. There are some models which use a slip Iii. These may require special installation techniques. Another type or pin fitting is loose on one side and tight on the other. This type aids in removal of the pin without collapsing the piston. With this design, always press on the pin from the loose boss side. The piston is marked on the inside of the piston skirt with the word "loose· to identify the loose boss. Always press with the loose side up and press the pin all the way through and out. When installing, press with the loose side up. In all pressing operations, set the piston in a cradle block to support the piston. Some pistons require heating to expand \he piston bosses so the pin can be pressed out without collapsing the piston. Other pistons just have a slip fit. INSPECTION • See Figures 50 thru 55 Check the piston pin retainer grooves for evidence of the retainers moving as they may have been distorted. Always replace the retainers once they have been removed. If there is evidence of wear in any of these areas, the piston should be replaced. Inspect piston pin for wear in the bearing area. Rust marks caused by water will leave a needle bearing imprint. Chatter marks on the pin indicate that the piston pin l&ll7P45 Fig.47 The holes in the bottom of this pis· ton pin bore provide oiling to the piston pin . . . Fig. 48 A similar hole in the connecting rod also oils the pin 050Q7P37 Fig. 49This piston uses a floating pin design. Once the retainers are removed, the pin should slide out easily 7-26 POWER HEAD :r ,'· Fig. 52 . . . and also at the point where the pin aligns with the connecting rod bore pins ... needle bearings i!i00i1'39 Fig.55 The small end bore in the connecting rod must be perfectly round to prevent bearing troubles should be replaced. If these marks are not too heavy, they may possibly be cleaned with emery paper lor loose needle bearings or crocus cloth lor caged bearings. IIthe piston pin checks out visually, measure its outside diameter and compare that measurement with the inside diameter of the piston pin bore. Proper clearance is vital to providing enough lubrication. Piston Rings GENERAL INFORMATION • See Figure 56 The piston ring seals the piston to the cylinder bore, just as other seals are used on the crankshaft and lower unit. To perform correctly, the rings must confollTI to !he cylinder wall and maintain adequate pressure to insure their sealing action at required operating speeds and temperatures. There are different designs used throughout the outboard industry. A given manufacturer will select a ring design that meets the operating requirements of the powerhead. This may be a standard ring, a pressure back (Keystone) ring or a combination of rings. The functions ol the piston ring include sealing the combustion gases so they cannot pass between the piston and the cylinder wall into the crankcase upsetting the pulse and maintaining an oil film in conjunction wilh the cylinder wall finish throughout the ring travel area. The rings also transfer heat picked up by the piston during combustion. This heat is transferred into the cylinder wall and thus to the cooling system. There are either two or three rings per piston, which perform these functions. •An oil control ring is not used on 2-stroke engines. All piston rings used are of the compression type. This means that they are for sealing the clearance between piston and cylinder wall. They are not allowed to rotate on the piston as automotive piston rings do. They are prevented from rotating by a Fig. 56 The piston ring seals the piston to the cylinder bore 0500/P/1 05007P83 Fig. 50 Measuring the piston pin bore Fig. 51 Measuring the piston pin outside inside diameter. This reading will be com diameter with an outside micrometer at the point where the pin aligns with the pared with the piston pin outside diameter piston pin bore . . . to determine pin-to-bore clearance 050071'38 Fig. 53 Some powerheads use a caged bearing design used to support piston Fig. 54 .. . while others use individual pin in the piston ring groove. If the ring was allowed to turn, a ring end could snap into the cylinder port and become broken. The ring ends are specially machined to compensate for the pin. As the rings warm up in a running powerhead they expand, thereby requiring a specific end gap between the ring ends for expansion. This ring gap decreases upon warm-up, effectively limiting blowing gases (from the combustion process) from going into the crankcase. The rings ride in a piston ring groove with minimal side clearance, which gives them support as !hey move up and down the cylinder wall. With this support, combustion gas pressure and oil eHeclively seal the piston ring against the ring land and the cylinder wall. As long as the oil mix is correct and temperatures remain where they should, the rings will provide service for many hours or operation. :r '· INSPECTION • See Figures 57 thru 62 One of the first indications of ring trouble is the toss of compression and performance. When compression has been lost or lowered because of the ring not sealing, the ring is either broken or stuck with carbon. gum or varnish. Improper oil mixing and stale gasoline provide the carbon, gum and varnish which cause the rings to stick. Low octane fuel, improperly adjusted timing/synchronization and lean fuel mixtures can damage the ring land, causing the ring to stick or break .-Running the outboard out of the water for even a few seconds can have damaging effects on the rings, pistons, cylinder walls and water pump. To determine if the rings fit the cylinder and piston, two measurements are taken: ring gap and ring side clearance. To determine these measurements, the ring is pushed into the cylinder bore using the piston skirt. so it will be square. Position each ring, one at a time, at the bottom of the cylinder (the smallest diameter) and using a feeler gauge, measure the expansion space between the ring ends. This is known as the ring gap measurement. Compare this measurement against the specifications. If the measurement is too small, the ring must be filed to increase the gap. If it is too large, either the bol'e is too large or the ring is not correct for the powerhead. After ring end gap has been determined. position each ring in the piston ring groove and using a feeler gauge. measure between the ring and the piston ring land. Compare this measurement against the specifications. If the measurement is too small, the ring groove may be compressed. Inspect the ring groove and ring land condition. If it is too large the ring may not correct tor the powerhead. Connecting Rods GENERAL INFORMATION The connecting rod transfers the combustion pressure from the piston pin to the crankshaft. changing the vertical motion into rotary motion. In doing so, the connect0l0011'62 POWER HEAD 7-27 ing rod swings back and forth on the piston pin like a pendulum while it is traveling up and down. It goes down by combustion pressure and goes up by flywheel momentum and/or other power strokes on a multi-cylinder powerhead. The connecting rod can be of aluminum on smaller horsepower fishing outboards or of steel on larger horsepower models. Most connecting rod designs use a steel liner with needle bearings in the !arge end and a pressed-in needle bearing in the small end. The steel rod is a bearing race at both the large and small ends of the rod. It is hardened to withstand the rolling pressures applied from the loose or caged needle bearings. Unlike many connecting rod designs. these rods do not use two piece caps. The connecting rod big end is one piece. This requires the crankshaft to be pressed together to form a rotating assembly With the connecting rods. The connecting rods are mist lubricated. Some of the rods have a trough design in the shank area. Oil holes may be drilled into the bearing area at both ends of this trough. Oil mist that falls out of the fuel will settle into the rod trough and collect. As the rod moves in and out, the oil is sloshed back and forth in the trough and out the oil holes into the rod or piston pin bearings. This provides sufficient lubrication for these bearings. When the rod is equipped with oi I holes, the oil holes have to be placed in the upward position toward the tapered end of the crankshaft when reassembled. INSPECTION t See Figures 63, 64, 65 and 66 Damage to the connecting rod can be caused by rack of lubrication and will result in galling of the bearing and eventual seizing to the crankshaft. Over speeding of the powerhead may also cause the upper shank area of the rod to stretch and break near the piston pin. Steel rods are inspected in the bearing areas, much like you would inspect a roller bearing. Look lor scoring, pit marks, chatter marks. rust and color change. A Blue color indicates overheating of the bearing surface. Minor rust marks or scoring may be cleaned up using crocus cloth for caged needle bearings or emery paper for loose needle bearings. A piece of round stock, cut with a slot in one end to accept a small piece of emery paper and mounted in a drill motor, can be used to clean up the rod ends. 0l001P42 Fig. 57 To determine ring gap, use a feeler gauge to measure the expansion space between the ring ends_ with the ring installed in the cylinder Fig. 58 Some rings are square . Fig. 59 . . . while other rings have a notched shape 0l007G38 Fig. 60 One way to Install piston rings is to place the ring in the groove and work it around the piston using a spiral motion until the ring is properly seated . . . Fig. 61 . . but the best way to install piston rings is to use a ring expander Fig. 62 Decarbon the piston rings using a ring groove cleaner or a broken piece of piston ring 7-28 POWER HEAD ,·OSOOI610 Slde view Com1e1 End view Correct Riclge OlSS6I't1 Fig.64 Damage to the connecting rod can be caused by lack of lubrication and will result In galling of the bearing and even· tual seizing to the crankshaft IXlmG34 fig. 66 Rod caps can only be Installed In one direction. The caps have been correctly Installed If no ridge can be fell Cl51ft6 The rod also needs to be checked lo see II il ls benl or has a lwlsl ln it. To do !his, remove the pislofl and place the rod on a surface plate or a piece olllat glass (automotive widow). Using a flash tight behind the rod and lookinglrom in front of the rod, check for any light which can beseen under the rod enos. II tighl can be seen shiningunder the rod ends, the rod is bent and it must oe replaced. Youcan also use a.002 feeler gauge. See ifitwill star! underthe machined aiea olthe rod. li lt will.the rod is benl Examinethe rod bolts and studs for damage and replace the nuts where used. Always reins!all the rod back on the same journal from whtch it was removed. The needlebearings. rod bearing surlace and crankshal\journal are all mated to eachother once the powerhead has been run. Fig. 67 Crankshaft assembly-V-type powerhead ..When installing the connecting rod, the long sloping side must be Installed toward the exhaust side of the cylinder assembly and if there Is a hole in the connecting rod, position the oil hole upward. Some piston designs are marked with the word "UP". This side should be placed toward the tapered end ol the crankshaft. Crankshaft GENERAL INFORMATION • See Figures 67, 68, and 69 The crankshaH is used to convert vertical motion received from the mounted connecting rod into rotary motion, which turns the driveshatl. lt mounts lhe flywheel, which imparls a momentum to smooth out pulses belween power strokes. It also provides sealing surfaces for the upper and lower seals and provides a surface for Fig. 68 Crankshaft assembly-single cylinder powerhead fig. 63On connecting rods without rod caps, check for side clearance between the crankshaft journals using a dial indicator as illustrated. For connecting rods with caps, use a feeler gauge between the con necting rod and the crankshaft journal Ag. 65 Minor rust marks or scoring may be cleaned up using crocus cloth for caged needle bearings or emery paper for loose needle bearings POWER HEAD 7-29 ,. '· 1 111213 Crank pin bearing 1415 Circlip 16 Piston pin bearing Lower crankshaft wheel 17 P1ston pin Lower crankshaft 18 Piston Oil seal 19 Piston ring 10 Lower oil seal gasket 20 Oil seal 05001G3G Fig. 69 Exploded view.of a crankshaft assembly with major compoBearings GENERAL INFORMATION • See Figure 72 Needle bearings are used to carry the load which is applied to the piston and rod. tion between the crankshaft and the connecting rod. They roll with little effort and at times have been referred to as anti-friction bearings, as they reduce friction by reducing the surface area that is in contact with the crankshaft and the connecting rod. These needle bearings are of two types, loose and caged. When loose bearings are 0501l1P46050D7P82Fig. 70 Crankshaft seals should always be lubricated prior to installation Fig. 71 Most crankshafts use two types of seals, an 0-ring and sealing ring Fig. 72 Typical caged bearing assembly the flywheel, the powerhead timing will be oil. Shim Lower oil seal housing 2 Crankshaft assy 3 Crank pin Upper crankshaft 45 Upper crankshaft wheel Connecting rod Bearing 6 7 Oil seal 8 9 This load is developed in the combustion process and the bearings reduce the fric used. there can be upwards to 32 loose bearings floating between the rod journal of nents identified the crankshal! and the connecting rod. These bearings are aided in rolling by the the labyrinth seal to hold oil against and a groove in which sealing rings are installed to seal pressures into each crankcase. Mounted main bearings control the axial movement of the crankshaft as it accomplishes these functions. The crankshaft bearing journals are case hardened to be able to withstand the stresses applied by the floating needle bearings used for connecting rod and main bearings. In essence. the crankshaft journals are the inner bearing races for the needle bearings. INSPECTION • See Figures 70 and 71 Pressure from the power stoke applied to the crankshaft rod journal by the needle bearings has a tendency to wear !he journal on one side. During crankshaft inspection, the journals should also be measured with a micrometer to determine if they are round and straight. They should also be inspected for scoring, pitting, rust marks, chatter marks and discoloration caused by heat. Check the sealing surfaces for grooves worn in by the upper and lower crankshaft seals. Take a look at the splined area which receives the driveshaft. Inspect the side of the splines for wear. This wear can be caused tiflack of lubrication or improper lubricant applied during a seasonal service. An exhaust housing/lower unit that has received a sudden impact can be warped and this can also cause spline damage in the crankshaft The crankshaft cannot be repaired because of the case hardening and the possibility of changing the metallurgical properties of the material during the welding and machine operation. Also. there are no oversized bearings available. Repairs are limited to cleaning up the journal surface with 320emery paper when loose needle bearings are run on the journal. Where caged roller bearings are run. the journal may be polished with crocus cloth. The tapered end of the crankshaft has a spline or a keyway and key which times the flywheel to the crankshaft. Inspect the spline or key and keyway for damage. The crankshaft taper should be clean and free of scoring, rust and lubrication. The taper must match the flywheel hub. If someone has hit the flywheel with a heavy hammer or has used an improper puller to remove the flywheel, the flywheel and hub may be warped. Place the flywheel on the tapered end of the crankshaft and check the fit. II there is any rocking indication a distorted hub, replace the flywheel. Always use a puller which pulls from the bolt pattern or threaded inner hub of the flywheel. Never use a puller on the outside of the flywheel. Thetaper is used to lock the flywheel hub to the crankshaft. When mounting the flywheel to the crankshaft the taper on the crankshaft an in the flywheel hub must be cleaned with a fast evaporating solvent. No lubrication on the crankshaft !aper or flywheel hub should be done. The flywheel nut must be torqued to specification to obtain a press fit between the flywheel hub and the crankshaft taper. If the nul is not brought to specifications. the flywheel may spin on the crankshaft causing major damage. The flywheel key is for alignment purposes and sets the flywheel's relative position to the cranksha«. Check the key for partial shearing on the side. If there is any Indication of shearing. replace the key. Also check the keyway in the flywheel and crankshaft for damage. IIthere is damage which will allow incorrect positioning of 7-30 POWER HEAD movement of the crank pin journal and the connecting rod pendulum action. The surface installed on the journal and rod encourages needle rotation because of its relative roughness. If the journal and rodsurface was polished with crocus cloth, the loose needle bearings would have the tendency to scoot, wearing both surfaces. So, journals and rods which uses the loose needle bearings are cleaned up sing 320 grit em9ry paper. Caged needle bearings used a reduced number of needles and the needles are kept separated and are encouraged to roll by the cage. The cage also controls end movement of the bearings. Because of the cage, the journal and rod surfaces can be smoother, so these surfaces are polished with crocus cloth. Main bearings are used to mount and control the axial movement of the crankshall. They are either ball, needle or split race needle bearings. The split race needle bearings are held together with a ring and are sandwiched between the crankcase and cylinder assembly. The split race bearings are commonly used as center main bearings, as this is the only type of bearing that can be easily installed in this location. The ball bearings may be mounted as top or bottom mains on the crankshaft The bearing is made up of three parts-the inner race, needle and the outer race. In most industrial applications, the outer or inner race of a needle bearing assembly is held in a fixed position by a housing or shaft. The connecting rod needle bearings in the outboard powerhead have the same basic parts but diller in thai both inner and outer races are in motion. The outer race-the connecting rod-is swinging like a clock pendulum. The inner rgce-lhe crankshafl-is rotating and the needle bearing Is floating between the two rat:es. INSPECTION Whenthe powerhead is disassembled and inspection of the parts is made, then by necessity along with examining the needle bearings, the crankshaft main bearing journal. rod journal and connecting rod bearing surfaces are also examined. The surfaces of all three ofthese parts can give a tremendous amountof information and the examination will determine if the parts are reusable. Surfaces shouldbeexamined for scoring, pitting, chatter marks, rust marks. spalling and discoloration from overheating of the bearing surfaces. Minor scoring or pitting and rust marks may be cleaned up and the surfaces brought back to a sat is :r factory condition. This is done using crocus cloth for caged needle bearings and 320 grit emery paper for loose needle bearings. This is not a metal removing process, rather just a clean up of the surfaces. Needle bearings are used as main bearings and are inspected for the same condi· lions as listed above. There are no oversized bearings available for rod ormain bearings. Because of the hardness of the crankshaft (a bearing race). it should not be turned or welded up in order to bring it back to standard size. The welding process may stress the metallurgical properties of thecrankshaft, developing cracks. The caged rod bearings and split race main bearings are inspected for the same condition as loose needle bearings. plus the cage Is examined for wear, cracks and breaks. Ball bearings are usedlor top and bottom main bearings in some powerheads. These may be pressed onto the crankshaft or pressed into the end cap. To examine lhese bearings, wash, dry, oil and check them on the crankshaft or in the bearing cap. Turn the bearing by hand and feel if there is any roughness or catching. Try to wobble the bearing by grasping the outer race, (inner race) checking for looseness of the bearing. Replace the bearing if any of these conditions are found. If the bearing is pressed off (out) the bearing will probably be damaged and should be replaced. If new or used bearings are contaminated with grit or dirt particles at the time of installation, abrasion will naturally lollow. Many bearing failures are due to lhe introduction of foreign material into the internal parts of the bearing duringassembly. Misalignment ol the rod cap .. torque of the rod bolts and lack of proper lubrication also cause failures. Bearing failure is usually detected by a gradual rise in operating noise. excessive looseness (axial) in the bearing and shaft deflection. Keep the work area clean and use needle bearing grease or multipurpose grease to hold the bearings in place. Thisgrease will dissipate quickly as the luel mixture comes in contact with it. Do not usea wheel bearing or chassis grease as this will cause damage to thebearings. Oil the ball bearings with 2-stroke oil upon installation. Remember to keep them clean. Powerhead Exploded Views • See Figures 73 thru 93 03578GOO 0357&304 Fig. 73 Exploded view of the cylinder block and crankcase cover Fig. 74 Exploded view of the cylinder block and crankcase cover with major parts idenlified-2.5, 3 and 3.3 hp with major parts idenlified--4 and 5 hp , '· Fig. 75 Exploded view of the cylinder block and crankcase cover with major parts identllied-s, 8, 9.9 and 15 hp Fig. 76 Exploded view of the crankshaft with major parts Identified -s, 8, 9.9 and 15 hp POWER HEAD 7-31 Fi g. 77 Exploded view of the cylinder block and crankcase cover with major parts ldentllled-20 and 25 hp ,...:.. :-.............. .. Oil'----J ..seal Ring gerd.*'.. Loci< ringScrew (4) (electric4) Flywheel ""(woodruff)-r ,; I ¢. PISton .. bearing• · 0 (27eachR ller piston) (2) pinSeal cap.. (2) Wear ThrOst race sleeve washert2) IConnectingrod (2) OW8Gil Fig. 78 Exploded view of the crankshaft with major parts ldenll· lled-20 and 25 hp ,'· 7-32 POWER HEAD 0:!658603 Fi g. 79 Exploded view of the cylinder block and crankcase assembly (top) and the end caps and exhaust cover (boltom}--4D hp (4-Cylinder) Fig. 80 Exploded view of the crankshaft, pistons and connecting rods"--'40 hp (4-Cylinder) Cylil'ld&rblock \ seal-e; pin lowt.t ....... ll'\t-a5Ct). maniklld Fig. 81 Exploded view of the crankcase-50 and 60 hp ....0 /C·Iod<or Oil... ., ROdbearing .. I Rolferbearinges...bfy ..GI4 Fig. 82 Exploded view of the crankshal1, pistons and connecting rods-50 and 60 hp POWER HEAD 7-33 Fig. 83 Exploded view of the crankcase-75 and 90 hp warn.nv module Exhaust """"' 03668C17 Fig. 85 Exploded view of the crankcase-100, 115 and 125 hp Oil pump dri,.geor ..../Key ma1n b&rtring 80 03668G18 Fig. 86 Exploded view of the crankshaft, pistons and connecting rods-100, 115 and 125 hp '· 0366EG15 Fig. 84 Exploded view of the crankshaft, pistons and connecting rods-75 and 90 hp >f ..7- 34 POWER HEAD Fig. 87 Exploded view of the crankcase-135-200 hp PiS1on lockring P•ston "--c ..Connectin;pod --.. Neede ,._-bearings (29perpiston) ..J..-- r I I Lo:.ating washer {12J)Ics) 03735619 037JilC20 Fig. 88 Exploded view of the crankshaft, pistons and connecting rods (Serial No. 00050182 and higher do not have a sealing ring installed immediately above the lower roller bearing)-135-200 hp Fig. 89 Exploded view of the crankcase-225 hp 0313fl:i22 Fig. 90 Exploded view of the crankshaft, pistons and connecting rods-225 hp :r tc '· Crankcase block Fig. 91 Exploded view of the crankcase-275 hp o-Retaitllng1ingdrlvegt-at ..Seal Se:at.. 00738G2. Fig. 92 Exploded view of the crankshaft, pistons and connecting rods-275 hp POWER HEAD 03738623 Exhaoo1 manifo6d 0373SG25 7-35 Fig. 93 Exploded view of the exhaust manifold and cylinder head assemblies-275 hp :r 7-36 POWERHEAD Torque Sequence Diagrams • See Figures 94 thru 118 Fig. 94 Apply a Y1e in. thick continuous bead of Locme• sealant between the cyliryler block and crankcase cover as lllustrated--40 hp ( 4-Cylinder) Fig. 95 Crankcase cover bolt torque sequence--40 hp ( 4-Cylinder) ..111310 Fig. 96 Cylinder block cover boll torque sequence--40 hp ( 4-Cylinder) 03G511G24 Fig. 99 Crankcase cover boll torque sequence. Tighten the large bolts first in sequence and then the small bolts in sequence-51Hi0 hp 03658621 Fig. 97 Apply a Y1e in. thick continuous bead of Loctlle8 sealant between the cylinder block and crankcase cover as illustrated-56-90 hp Fig. 100 Exhaust cover boll torque sequence-56-90 hp Fig. 98 Crankcase cover bolt torque sequence-50-60 hp Fig. 101 Cylinder cover bolt torque sequence-50-90 hp POWER HEAD 7-37 ?f '· OlS58G30 Fig. 102 Intake manil..ld bolt torque sequence-56-60 hp 036511G25 Fig. 105 Crankcase cover bolt torque sequence. Tighten the large bolts first in sequence and then the small bolts in sequence-100-125 hp 036S&l32 Fig. 108 Intake manifold bolt torque sequence-100-125 hp OO!SSG31 Fig. 103 Intake manifold boll torque sequence-75-90 hp Fig. 106 Exhaust cover bolt torque sequence--100-125 hp 03738G3$ Fig. 109 % in. crankcase cover boll torque sequence-135-200 hp Fig. 104 Apply a1J16in. thick continuous bead ol Loclile8 sealant between the cylinder block and crankcase cover as illustrated-100-125 hp 031JSGJ6 Fig. 110 SAs in. crankcase cover bolt torque sequence-135-200 hp 03651!629 Fig. 107 Cylinder cover bolt torque sequence--100-125 hp 7-38 POWERHEAD I 0373aG57 Fig. 111 Crankcise cover bolt torque sequence-225 hp Ag. 114 Exhaust cover bolt torque sequence-15D-200 hp (153 cubic inch) 03738GJ7 Fig. 112 Crankcase cover bolt torque sequence-256-275 hp 12 0 100 ou8 0 0 7 4 0 0 5 1 0 0 2 5 0 0 69 00 0 015 14 15 03738G45 Fig. 115 Exhaust cover bolt torque sequence-225-275 hp Fig. 117 Cylinder cover bolt torque sequence-225 hp 037JSG43 Fig. 113 Exhaust cover bolt torque sequence-135-200 hp 03139646 Fig. 116 Cylinder cover bolt torque sequence-135-200 hp Component/Model....!OnY:Il2nrnl«rnn,.., ..bolls 2.$,3.3"'3.4-SIIp&. a. s . s . 15"' 20.251950.6019--..- 6,&,U.1519 20,.25"' 40"' 135-200"'C)Worl-' to.. 22.3.3"'3. ... 519 e. a, u. 15"' IJS.aiOt., (1990-83) 13&225 19 (1094-00) 6, 8, U, I5)1) 20. 25 ... 30,40..,50. 55 •.eo50. s.s. eo 11p (>'le lip (11411. .. nbel>) 15, 90, 100 , 115. 125 lip IJ5.27511p Engine Torque Specifications Stand11rd {ft. lb$.J 3.06.0 132113171lnt.s.eotiCISIIin.lls 2Sin ...TSnbs.60 ...... 11eo40 30 (+60 1 8.315IIti!Onlbs.273030 Metric (Nm) •1&35"2 81.6IOU,,2.82Uu54.240JIU21.1203140J407 ..Q:j Componen1lMoclel2.5, 3.J.IIp 3.'.5 11pa.a.u,1S11p 20,2511p30,«<,50.60 lip75, tl(lllp .. l>albJ .. 90 ..pI.,.. ba1ts1100. 115. 125"' 8,6,0...151920.ZS .30,ol.!lllp 75.90. 100. 115, 125 lip 135-200 lip...,_ bells) 1JIHOOI'Cl(Yt&.il,.. 135. 150. 175.200 "' ..end cap136.150, 175, 20011p P<-«Jdcapbols 2:2! lip Cl• t.2S rrmbc!!s)22SIIp(10s. l.5rrm .. 21SIIpl't(Gel r..t 3,4,5"' U.U.15.20.25"'30,«119S0.22SIIp 2S0.2751'ClU,U,15"' ?O ,ZSIIp 30 ,-4DIIp..22SI'Cll.S, lHp 3.C.St.,·e.a.o...1st.,20.2519XI-12Sf'Cl13&25011p Engine Torque Specifications !Standard (fl. lba.J Met1lc 50i-l.lls 5.6 110m. bs. 10.3 1l6 22.$ 30 ..7 ,, z• 25 )I 185 25 1&.5 25!U 100 11\.bs. 11.2 1l6 25 38 ·su 15 20.3 tsonbs. 15.9 8011.bs. u 21 31.. 30 40.. 7 30 fl).7 .tiO 52.2 50 87.8 75 IOU 120 1112.7 100 135.0 eo ... t. E5 11.3 t1 '22.5 18 CJ......I (.r.) (C) _, Engine Torque Specifications Standatd (ft. lbs.) 30,40 "' 100i>.lb5. 70-\25 "' 18.5 20,25"' 150i>.lb5. 30-«) "' 50 75-125 "' 70 1..200"' 75 225 "' 100 175"' 10 2..5, 3.3"' 3.4.5"' 10i>.lb5. a.a.u, 1s"' 120nlb&. 20.2St., 17 30,40"' 13.550.60"' 28 75, llO"' 14100, 115"' (19IJO.i:ll 20 IW.115"'(1.. 44 131>225"' 20 250.ll5"' 30 3 ,4, 5 "' 12.5 U.U.15"' G ..-25 "' 10 »275"' 55 Silrlor_ID...._a.. "' (as..1Dmodol) 17 30,40 "' 15 50.55,60"' 18 75-115"' \U \25-225 "' f1.5 250.ll5"' 12.5 Wlllllpu111 .. 2.5, 3, 3.3 ,4,5 "' 10i\.b. 6.8.5.8, 151\1 40in.lb& . 20.25"' 2SR.t>s. 50-125"' 50ir\.lb&. Metric (Hm) \YaW p.l11) "'*' 11.3 .201)"' 2U 225-27 5"' Wllllrpu111 - 3. 4, 5"' 87.8 e. a. u. 15"' ..-i 101.7 Wat. pu111bady 138 30,40"' au 71>125 "' 2.5, 3.3"' 8 3,4,5"' 13.G 6-225 "' 22.6 :n s"' 18 38 lfllndlftind-.......t 18.6 2.5-25"' 311.5 '51.1 TFIIISfwpert 8nd intab! "'""' -ll ...a.u. 1s"' 40.7 20. 25"' lnloU nnifllld 511.125"' 8 13.6 c.tueta-Dpb-- 74.6 1.."' 20.3 24IU 2U 17 4.5 u 6.8 ..1m:tn Engine Torque Specifications StAndard (ft. Ill$.) 35 in. tl5. 6011\.bo. 10R.Ib&. .o;,a. . 30i\.lbs. 60IR.Ib&. 20 14 20 17 10ft.bo. 150in.lb& . ..in.tis. 18 Metric (Nm) 3.i u a 4.5 3.4 6.8 21.1 1&.7 21.1 23 8 u 3.A 24 12 1)5ffl.. .......I .. C) \J 0.. rn'IJ:r: rn )> 0 · '' . . , Engine Rebuilding Specifications 2.5, 3, 3.3 HP Maximum Standard Metric: ..Riddllecb 0.022 ...056 0.&-1.5 C)tndlr ben (i) 1.15 (7.05 C)tndlrben-Q) 1.152 (7,0(PisiDn ...cytindlr c:lenllce 0 .002...005 0.06-0.15 PisiDn ..IIIII1111P 0 .006-0 . 01.2 0.1$4.33 PisiDn ..lidlc:lenllce O.oool4 . 10 0 . 01.. .05.,_inlrn reed tql opening 0.23$-0.2(( I.G-e.2 (i) ........-z.: 1.869 on.(d ....endLD. 0.811 7 22.7S ..tl>dblgendLD. 1 . 198 30.38 ..""'.. 0.002 0.051 C)Modotlt 002027...1/ld below: The cylinder beret .weQlrune ll1d eannol .. rebcnd atlllcionl!y hontd. Checkotdl tyllnde! f01 "" 0111 -of...., ,.., 'egg sillpelt. 12> Oo\ modtlt 00202750 ll1d tllove; lht cyfinder block is M4rc:osil and lht cylnclers can bortbcrtd lo 0.030 ln. ovlrllze .chlcl< uch cylinder boraro-anout-olo.Wnd 'ess slllll*f' cylinder. amax lnllll ol 0 .003 n. (0 . 078nm) Is llloMd. 06197C07 051G700i -o0..rn::0 ::::r: rn :r> 0 .......I .... ., Engine Rebuilding Specifications -30, 40 (2-cylinder) HP Maximum Component Standard Metric (mm) ToprnaOI bong jac.NI I.J75 34.93moin btMil1g jcMmol 1.216 30.!9 8olbn bllbeft1g jcMINI 1.181 2U9Cannoeling!lidjacmel 1 .181 29.9e Connec:ting!lid 1111111 ond I. D . 0... 24.31 Connec:ting red big 001d I.D . 1... 38.07Connec:ting !lidaJ9wnent 0.002 0.051CyllncW..CD 2.893 78C)foder 0111 cl rOII'Id 0.003 0 . 08Baro.. Cos!IIUICykldor ... 0.003 o.oeC)tndor lnilll honii.D 2.193 76 Piston *'-11 sllh .. uaa 15.9 Piston IDcylndlrdolrwlc:e O.oo:l-0 ,004 0.076-0.101 Piston lt'Q 001d !liP 0.010-4.018 .:IS-.46l.tW'rMm roodopri1g 0.02 0.508 Reedrlop 30 ... 0.0!1 2.28640 ... e o.o __ .. ..., 3.Cylndw cisllrion 0,003 0.08 CJCyllndw ben type Cast ion Cylinder . 0.003 0.08 1980-1997 2.950 74.83 .015 il. (0.381 nm)CMnize 2..5 75,31.030 ln. (0.762 nm) oversile 2.880 75.st 05191CO!l 189&-2000 2.8118 75.1!85 ,015 in. (0 ,38 1nm)ov.We 3.0G3 76.276 ,030 ln. (0.762 nm) oversize 3.018 78.651Plslon ring end 111P 0.01...018 .254-.451M..reed .. 0.02 0.5Reed&!cp 4011' 0.08 U86 50,55,60 If> Ncn-Adjustallil ReedlhicW. 0,01 0.254 051S7C I1 051..7C\O Engine Rebuilding Speclfications-75, 90, 100, 115, 125 HP Component CrWikshlftl\llGIA Cyflldlrben 1890-1993 .OIS in. !0.3.!11 nwn)-. .030 in. j0.762nwn)CH.-slle IlOOO .015 in .j0 . 381 rrm) ow...a e .030 ln. j0.762rrm)rttl asmc 1 Engine Rebuilding Specifications-QptiMax 200 and 225 HPStandardComponent St8nd.ard (ln.) Metric CnntshallMCIUt O.D02 0.0508 CytilcW ben 3.6265 92.1131 .015in. (0.38111'f11 ) -*:t 3.641 5 924941.030 in. (0.762rm1)wtnize 3.6565 92.6751 ..bcret,'pt ..Cast ton Cyindlr cbbko. 0.003 0.076 Pision..(J) 3.821S3 6205 SU861-SI .9607 .015in. (0.3.!1111'f11 ) CNW'Siu 3.636S-3.635S 92.3671..17 .030 in. (0.762 11'f11 ) ownlzt 3.6S \S3... 92.7481-12.7227 R*Sialld.. 0.020 0.50Cytlcler ..eaicn 110-135psi 753.3-92 4. 5kPa (J) Twa0 700n (17.7&"""' mdp.oton.A. !10<119-"""'pst>n pn; It mine-pston pinllii:Jon:goQ A _. btO.COUIOOIS n less 4.,... s-olfpst>n (..... Engine Rebuilding Specifications-OptiMax 115, 135, 150 HPStandardCompoHnt Standard (ln.) Mett le (mm) OrishlllMOUI 0.006 0. 152 Cyindwbcre 3.501 euzs .0 15 it (0.381 11111} -*:e 3.515 eo.. Cyindw bare tJpt Cast ton Cylinderislon' A.90degofts mptnDOpon;!!. nn'MIIp!SIOI> p....llwMnston A .. bo 0 001 -ll 0015 01. less 4 .. II _,.oil patorl (.....- ISI'irTI! 1)51.... -oC) .. rn :0 ::r: rn ::t> 0 ...._,.I .. w 7-44 POWERHEAD Engine Rebuilding Specifications-250 and 275 HP Standard Component Standard (in.) Metric (mm) Cmod side clearance 0.003-0.009 0.07-0.22Cylinder bore 3.74 95.00 Cylinder bore type