F250AFL250ASERVICE MANUAL6P2-28197-3H-11NOTICEThis manual has been prepared by Yamaha primarily for use by Yamaha dealers and their trainedmechanicswhenperformingmaintenanceproceduresandrepairstoYamahaequipment.Ithasbeen written to suit the needs of persons who have a basic understanding of the mechanical andelectricalconceptsandproceduresinherentinthework,forwithoutsuchknowledgeattemptedrepairs or service to the equipment could render it unsafe or unfit for use.BecauseYamahahasapolicyofcontinuouslyimprovingitsproducts,modelsmaydifferindetailfromthedescriptionsandillustrationsgiveninthispublication.Useonlythelatesteditionofthismanual.AuthorizedYamahadealersarenotifiedperiodicallyofmodificationsandsignificantchanges in specifications and procedures, and these are incorporated in successive editions of thismanual.Important information 1Particularly important information is distinguished in this manual by the following notations:TheSafetyAlertSymbolmeansATTENTION!BECOMEALERT!YOURSAFETYISINVOLVED! WARNINGFailure to follow WARNING instructions could result in severe injury or death to the machineoperator, a bystander, or a person inspecting or repairing the outboard motor.CAUTION:ACAUTIONindicatesspecialprecautionsthatmustbetakentoavoiddamagetotheout-board motor.NOTE:A NOTE provides key information to make procedures easier or clearer.F250A, FL250ASERVICE MANUAL2013 by Yamaha Motor Co., Ltd.3rd Edition, January 2013All rights reserved.Any reprinting or unauthorized use without the written permission of Yamaha Motor Co., Ltd. is expressly prohibited.Printed in the NetherlandsContentsGeneral information1GEN INFOSpecification2SPECPeriodic check and adjustment3CHK ADJFuel system4FUELPower unit5POWRLower unit6LOWRBracket unit7BRKTElectrical system8ELECTroubleshooting9TRBL SHTGIndex +GEN INFO6P23H11General informationHow to use this manual ................................................................................. 1-1Manual format............................................................................................ 1-1Symbol....................................................................................................... 1-2Abbreviation............................................................................................... 1-3Safety while working...................................................................................... 1-4Fire prevention........................................................................................... 1-4Ventilation.................................................................................................. 1-4Self-protection ........................................................................................... 1-4Part, lubricant, and sealant........................................................................ 1-4Good working practice............................................................................... 1-5Disassembly and assembly....................................................................... 1-5Identification................................................................................................... 1-6Model ......................................................................................................... 1-6Serial number ............................................................................................ 1-6Special service tool ....................................................................................... 1-7Feature and benefit ...................................................................................... 1-14ECM system............................................................................................ 1-14Electronic fuel injection control system.................................................... 1-22Ignition timing control system.................................................................. 1-25Knock control system.............................................................................. 1-27Variable camshaft timing control system................................................. 1-29Electronic throttle valve control system................................................... 1-33Engine speed control system.................................................................. 1-35Lower unit ................................................................................................ 1-38Propeller selection....................................................................................... 1-39Propeller size........................................................................................... 1-39Selection.................................................................................................. 1-396P23H11123456789Predelivery check ........................................................................................ 1-40Checking the fuel system ........................................................................ 1-40Checking the engine oil level ................................................................... 1-40Checking the gear oil level ...................................................................... 1-40Checking the battery................................................................................ 1-40Checking the outboard motor mounting height........................................ 1-41Checking the remote control cable.......................................................... 1-41Checking the steering system................................................................. 1-42Checking the gear shift and throttle operation......................................... 1-42Checking the PTT system....................................................................... 1-42Checking the engine start switch and engine stop lanyard switch .......... 1-42Checking the cooling water pilot hole...................................................... 1-43Test run ................................................................................................... 1-43Break-in ................................................................................................... 1-43After test run............................................................................................ 1-43GEN INFOGeneral information1-1 6P23H11How to use this manual 1Manual formatThe format of this manual has been designed to make service procedures clear and easy to under-stand. Use the information below as a guide for effective and quality service. Parts are shown and detailed in an exploded diagram and are listed in the component list (see 1in the figure below for an example page). The component list consists of part names and quantities, as well as bolt and screw dimensions(see 2 in the figure below). Symbols are used to indicate important aspects of a procedure, such as the grade of lubricant andlubrication point (see 3 in the figure below). Tightening torque specifications are provided in the exploded diagrams (see 4 in the figure belowfor an example), and in the related detailed instructions. Some torque specifications are listed instages as torque figures or angles in degrees. Separateproceduresandillustrationsareusedtoexplainthedetailsofremoval,checking,andinstallation where necessary (see 5 in the figure below for an example page).NOTE:For troubleshooting procedures, see Chapter 9, Troubleshooting.LOWRLower unit6-5 62Y5A11Lower unitNo. Part name Qty Remarks1 Lower unit 12 Plastic tie 1 Not reusable3 Hose 14 Check screw 15 Gasket 2 Not reusable6 Dowel pin 27 Bolt 4 M10 40 mm8 Drain screw 19 Grommet 110 Bolt 1 M1045 mm11 Bolt 1 M8 60 mm12 Thrust washer 113 Propeller 114 Washer 115 Washer 116 Cotter pin 1 Not reusable17 Propeller nut 118 Trim tab 1LOWRLower unit6-19 62Y5A11Removing the drive shaft1. Removethedriveshaftassemblyandpinion,andthenpullouttheforwardgear.Disassembling the drive shaft1. Installthepinionnut1,tightenitfingertight,andthenremovethedriveshaftbearing 2 using a press.CAUTION: Donotpressthedriveshaftthreadsadirectly. Donotreusethebearing,alwaysreplace it with a new one.Disassembling the forward gear1. Remove the taper roller bearing from theforward gear using a press.CAUTION:Donotreusethebearing,alwaysreplaceit with a new one.2. Remove the needle bearing from the for-ward gear.CAUTION:Donotreusethebearing,alwaysreplaceit with a new one.Bearing inner race attachment 3:90890-06639Bearing separator 1: 90890-06534Stopper guide plate 2: 90890-06501Stopper guide stand 3:90890-06538Bearing puller 4: 90890-06535Bearing puller claw 1 5:90890-06536S62Y6740KDrive shaft holder 4 1: 90890-06518Pinion nut holder 2:New: 90890-06715Current: 90890-06505S68S6360J12523416P23H11 1-2123456789SymbolThe symbols below are designed to indicate the content of a chapter.General informationSpecificationPeriodic check and adjustmentFuel systemPower unitLower unitBracket unitElectrical systemTroubleshootingGENINFOSPECCHKADJFUELPOWRLOWRBRKTELECTRBLSHTG +Symbols 1 to 6 indicate specific data.1 Special service tool2 Specified oil or fluid3 Specified engine speed4 Specified tightening torque5 Specified measurement6 Specified electrical value (resistance, voltage, electric current)Symbols 7 to C in an exploded diagram indicate the grade of lubricant and the lubrication point.7 Apply Yamaha 4-stroke motor oil8 Apply gear oil9 Apply water resistant grease (Yamaha grease A)0 Apply molybdenum disulfide greaseA Apply corrosion resistant grease (Yamaha grease D)B Apply low temperature resistant grease (Yamaha grease C)C Apply injector greaseSymbols D to I in an exploded diagram indicate the type of sealant or locking agent and the appli-cation point.D Apply Gasket Maker E Apply ThreeBond 1104JF Apply LOCTITE 271 (red)G Apply LOCTITE 242 (blue)H Apply LOCTITE 572I Apply silicon sealant1 2 3 4 5 6T R..7 8 9 0 A B CE GA M D C ID E F G H IGM1104J271LT242LT572LTSSHow to use this manualGEN INFOGeneral information1-3 6P23H11AbbreviationThe following abbreviations are used in this service manual.Abbreviation DescriptionAFT Aft endAPI American Petroleum InstituteBOW Bow endCCA Cold Cranking AmpereDES Dual Engine SystemECM Electronic Control ModuleEN European Norm (European standard)EX ExhaustIEC International Electrotechnical CommissionIN IntakePCV Pressure Control ValvePON Pump Octane Number = (RON + Motor Octane Number)/2PORT Port sidePTT Power Trim and TiltRON Research Octane NumberSAE Society of Automotive EngineersSTBD Starboard sideTDC Top Dead CenterTPS Throttle Position SensorUP UpsideYDIS Yamaha Diagnostic System6P23H11 1-4123456789Safety while working 1Topreventanaccidentorinjuryandtoensurequalityservice,followthesafetypro-cedures provided below.Fire preventionGasoline is highly flammable.Keepgasolineandallflammableproductsaway from heat, sparks, and open flames.VentilationGasoline vapor and exhaust gas are heavierthanairandextremelypoisonous.Ifinhaledinlargequantitiestheymaycauselossofconsciousness and death within a short time.When test running an engine indoors (e.g., inawatertank)besuretodosowhereade-quate ventilation can be maintained.Self-protectionProtect your eyes by wearing safety glassesor safety goggles during all operations involv-ing drilling and grinding, or when using an aircompressor. Protect your hands and feet by wearing pro-tective gloves and safety shoes when neces-sary.Part, lubricant, and sealantUseonlygenuineYamahaparts,lubricants,andsealantsorthoserecommendedbyYamaha, when servicing or repairing the out-board motor.Under normal conditions, the lubricants men-tionedinthismanualshouldnotharmorbehazardous to your skin. However, you shouldfollow these precautions to minimize any riskwhen working with lubricants.1. Maintain good standards of personal andindustrial hygiene.2. Changeandwashclothingassoonaspossible if soiled with lubricants.3. Avoidcontactwithskin.Donot,forexample,placeasoiledraginyourpocket.4. Washhandsandanyotherpartofthebody thoroughly with soap and hot wateraftercontactwitha lubricantorlubricantsoiled clothing has been made.5. Toprotectyourskin,applyaprotectivecreamtoyourhandsbeforeworkingonthe outboard motor.How to use this manual / Safety while workingGEN INFOGeneral information1-5 6P23H116. Keep a supply of clean, lint-free cloths forwiping up spills, etc.Good working practiceSpecial service toolUsetherecommendedspecialservicetoolstoprotectpartsfromdamage.Usetherighttool in the right mannerdo not improvise.Tightening torqueFollowthetighteningtorquespecificationsprovided throughout the manual. When tight-eningnuts,bolts,andscrews,tightenthelarge sizes first, and tighten fasteners startingin the center and moving outward.Non-reusable partAlways use new gaskets, seals, O-rings, cot-terpins,circlips,etc.,wheninstallingorassembling parts.Disassembly and assembly1. Use compressed air to remove dust anddirt during disassembly.2. Applyengineoiltothecontactsurfacesof moving parts before assembly.3. Installbearingswiththemanufactureidentificationmarkinthedirectionindi-catedintheinstallationprocedure.Inaddition, be sure to lubricate the bearingsliberally.4. Applyathincoatofwater-resistantgreasetothelipandperipheryofanoilseal before installation.5. Checkthatmovingpartsoperatenor-mally after assembly.6P23H11 1-6123456789Identification 1ModelThis manual covers the following model.Serial numberTheoutboardmotorserialnumberisstampedonalabelattachedtotheportclamp bracket.1 Model name2 Approved model code3 Transom height4 Serial numberApplicable modelF250AET, FL250AETModel nameApproved model codeStarting serial No.F250AET 6P2 1003034FL250AET 6P3 1000996Safety while working / IdentificationGEN INFOGeneral information1-7 6P23H11Special service tool 1Oil filter wrench90890-06830Leakage tester90890-06840Fuel pressure gauge adapter B90890-06942Fuel pressure gauge90890-06786Vacuum/pressure pump gauge set90890-06756Compression gauge90890-03160Compression gauge extension90890-06563Test harness (3 pins)90890-06869Flywheel holder90890-06522Flywheel puller90890-065216P23H11 1-8123456789Sheave holder90890-01701Valve spring compressor90890-04019Valve spring compressor attachment90890-06320Valve guide remover/installer90890-06801Valve guide installer90890-06810Valve guide reamer90890-06804Valve seat cutter holder90890-06316Valve seat cutter90890-06324, 90890-06325, 90890-06326, 90890-06816, 90890-06817Bearing inner race attachment90890-06640, 90890-06659, 90890-06661Driver rod L390890-06652Special service toolGEN INFOGeneral information1-9 6P23H11Needle bearing attachment90890-06607, 90890-06610, 90890-06611, 90890-06613, 90890-06653, 90890-06654Piston ring compressor90890-05158Bearing housing puller claw L90890-06502Stopper guide plate90890-06501Center bolt90890-06504Bearing separator90890-06534Stopper guide stand90890-06538Bearing puller assembly90890-06535Slide hammer90890-06531Bearing outer race puller assembly90890-065236P23H11 1-10123456789Outer race puller claw A90890-06532Driver rod SS90890-06604Bearing depth plate90890-06603Ball bearing attachment90890-06656, 90890-06657Driver rod LS90890-06606Bearing outer race attachment90890-06622, 90890-06628, 90890-06658Drive shaft holder 690890-06520Pinion nut holder90890-06715Ball bearing attachment90890-06655Driver rod LL90890-06605Special service toolGEN INFOGeneral information1-11 6P23H11Shift rod push arm90890-06052Pinion height gauge90890-06710Digital caliper90890-06704Shimming plate90890-06701Backlash indicator90890-06706Magnet base plate90890-07003Dial gauge set90890-01252Magnet base B90890-06844Puller head90890-06514Ring nut wrench90890-065786P23H11 1-12123456789PTT oil pressure gauge assembly90890-06580Cylinder-end screw wrench90890-06568PTT piston vice attachment90890-06572Tilt rod wrench90890-06569Digital circuit tester90890-03174Peak voltage adapter B90890-03172Ignition tester90890-06754Test harness (2 pins)90890-06867Test harness (1 pin)90890-06888Yamaha diagnostic system60V-85300-02-00Special service toolGEN INFOGeneral information1-13 6P23H11Yamaha diagnostic system60V-WS853-03Diagnostic flash indicator B90890-068656P23H11 1-14123456789Feature and benefit 1ECM systemIn the engine of the F250/FL250, the ECM controls the fuel injection volume, ignition timing, intakevalveopeningandclosingtiming,andtheelectronicthrottlevalveopeningangleaswellastheengine speed when the engine overheats and when the engine oil pressure is low. Reliable starting,stabilized trolling, excellent acceleration, maximum output, low fuel consumption, and low emissionsareachievedbymaintainingtheoptimumair-fuelrationandignitiontimingundervariousengineconditions.Electronic control module system diagramS6P21110:::High-pressure fuel pumpVapor separator tankLow- pressure fuel pumpOil control valve (PORT)Cam position sensor (PORT IN)Cam position sensor (PORT EX)ControlsignalCam position sensor (STBD IN)Oil control valve (STBD)Variable camshaft timing controlFuel injection controlIgnition timing controlAirFuelVapor gasFilterCanisterCheck valveFuelflowVapor gas flowFuel filter with water separatorVapor shut-off valveAir flowElectronic throttle valve assemblyTPS and Electronic throttle valve motorAccelerator position sensorElectronic throttle valve controlBatteryECMCrank position sensorIntake air pressure sensorOil pressure sensorEngine temperature sensorIntake air temperature sensorKnock sensorShift cut switchNeutral switchFuel injectorSpecial service tool / Feature and benefitGEN INFOGeneral information1-15 6P23H11ECM component1 Crank position sensor2 Oil control valve (PORT)3 Cam position sensor (PORT IN)4 Oil control valve (STBD)5 Cam position sensor (PORT EX)6 ECM7 Cam position sensor (STBD IN)8 Knock sensor9 Fuel injector0 Vapor separator tankA High-pressure fuel pumpB Check valveC Low-pressure fuel pumpD FilterE Intake air temperature sensorF Engine temperature sensor357E681F24CDB90AS6P211116P23H11 1-161234567891 Vapor shut-off valve2 TPS 13 TPS 24 Electronic throttle valve assembly5 Intake air pressure sensor6 Canister7 Fuel filter with water separator8 Neutral switch9 Shift cut switch0 Oil pressure sensorA Accelerator position sensor 1B Accelerator position sensor 2BA5023817469S6P21112Feature and benefitGEN INFOGeneral information1-17 6P23H11Sensor functionSensor FunctionCrank position sensor Detects the engine speed. Controls the ignition timing, fuel injection volume, engine speed, engine knock, variable camshaft timing, and electronic throttle valve opening angle. Detects the angle of the crankshaft and the position of the pistons.(Cannot detect the position of the exhaust and compression strokes.) Identifies cylinder groups #1 and #4, #2 and #5, and #3 and #6.Cam position sensor (PORT EX) Detects the stroke position.(Example: TDC of the compression stroke or TDC of the exhaust stroke.) Detects the strokes of the different cylinders using signals of both the crank position sensor and cam position sensor (PORT EX). Control the variable camshaft timing.Cam position sensor (STBD IN)Detects the starboard advance angle using variable camshaft timing control.Cam position sensor (PORT IN)Detects the port advance angle using variable camshaft timing control.TPS 1 Detects the electronic throttle valve opening angle.TPS 2 Detects the electronic throttle valve opening angle.Accelerator position sensor 1Detects the throttle lever opening angle.Accelerator position sensor 2Detects the throttle lever opening angle.Intake air pressure sensor Detects the intake air pressure and controls the ignition timing and fuel injection volume.Intake air temperature sensor Detects the intake air temperature and controls the correction of the ignition timing.Engine temperature sensor Controls the correction of the ignition timing and fuel injection volume.Neutral switch Detects the neutral position.Oil pressure sensorDetects the engine oil pressure and controls the warning and engine speed when the engine oil pressure is low.Thermoswitch Sends signals to warn that the engine is overheating and controls the engine speed when the overheat warning is activated.Shift cut switch Outputs signals to decrease the engine speed to facilitate shifting.Knock sensor Detects abnormal combustion knock and controls the ignition timing.6P23H11 1-18123456789Circuit diagramNOTE:The circled numbers in the illustration indicate the ECM terminal numbers.S6P2113016558375848166807953546263707156575860591532514936374840384441314750451ab c e d5V5V5V5VCrank position sensorCam position sensor (PORT EX)Cam position sensor (PORT IN)Cam position sensor (STBD IN)TPS 1TPS 2GroundGroundGroundAccelerator position sensor 1Accelerator position sensor 2Intake air pressure sensorOil pressure sensorECMFuel injector #1Fuel injector #2Fuel injector #3Fuel injector #4Fuel injector #5Fuel injector #6Ignition coil #1Ignition coil #2Ignition coil #3Ignition coil #4Ignition coil #5Ignition coil #6Electronic throttle valve relayElectronic throttle valve motorFeature and benefitGEN INFOGeneral information1-19 6P23H11S6P21140 +PPTBZ658572746764284668697673617786175261271334277881823c ab e d5V5V5V5VECMIntake air temperature sensorHigh-pressure fuel pump relayThermoswitchShift cut switchNeutral switchGroundKnock sensorEngine stop lanyard switchMain relayRectifier RegulatorBatteryEngine start switchOil control valve (STBD)Oil control valve (PORT)High-pressure fuel pumpLow-pressure fuel pumpVapor shut-off valveLow oil pressure warning indicatorOverheat warning indicatorDiagnosis indicatorBuzzer (DES switch)DES switchTachometerYDISEngine temperature sensor6P23H11 1-20123456789ECM coupler layoutS6P211501 2 3 4 5 6 789 1011 12 13 62 63 64 65 66 67 68 6970 71 72 73 74 75 76 7753 54 55 56 57 58 59 60 6178 79 80 81 82 83 84 85 8640 41 4243 44 4534 35 3637 38 3946 47 48 49 50 51 5227 28 29 30 31 32 3314 15 1617 18 1920 21 22 23 24 25 26No.Connecting part Color code1 Cam position sensor (STBD IN)White/black2 Cam position sensor (PORT IN)White/green3 Cam position sensor (PORT EX)White/blue456 Shift cut switch Blue/yellow7 Main relay Yellow/green8 Knock sensor Green9101112 Neutral switch Blue/green13 Engine start switch Yellow1415 Crank position sensor groundBlack16 Crank position sensor White/black17 Engine temperature sensorBlack/yellow18 Sensor ground Black1920212223 Intake air temperature sensorBlack/yellow24252627 Battery power source Red/yellow28 Personal computer White/black293031 Accelerator position sensor 1 (main)Pink/white323334 Battery power source Red/yellow3536 Intake air pressure sensorPink/green37 Oil pressure sensor Pink/white38 Accelerator position sensor 2 (sub)Pink3940 Accelerator position sensor 2 ground (sub)Black41 Accelerator position sensor 1 ground (main)Black424344 Accelerator position sensor 2 power source (sub)Orange45 TPS 1 (main) Pink46 Unit ground Black47 TPS ground Black48 Sensor power source Orange49 Accelerator position sensor 1 power source (main)Orange50 TPS 2 (sub) Pink/white51 TPS power source Orange52 Thermoswitch Pink53 Ignition coil #6 Black/brown54 Ignition coil #5 Black/blueNo.Connecting part Color codeFeature and benefitGEN INFOGeneral information1-21 6P23H11S6P211501 2 3 4 5 6 789 1011 12 13 62 63 64 65 66 67 68 6970 71 72 73 74 75 76 7753 54 55 56 57 58 59 60 6178 79 80 81 82 83 84 85 8640 41 4243 44 4534 35 3637 38 3946 47 48 49 50 51 5227 28 29 30 31 32 3314 15 1617 18 1920 21 22 23 24 25 26No.Connecting part Color code55 Fuel injector #6 Purple/white56 Fuel injector #5 Purple/blue57 Fuel injector #4 Purple/green58 Fuel injector #3 Purple/yellow59 Fuel injector #1 Purple/red60 Fuel injector #2 Purple/black61 Low-pressure fuel pumpBlue/white62 Ignition coil #4 Black/green63 Ignition coil #3 Black/yellow64 Tachometer Green65 High-pressure fuel pump relayBlue/red66 Electronic throttle valve relayYellow67 Buzzer Pink68 ECM ground Black69 ECM ground Black70 Ignition coil #2 Black/white71 Ignition coil #1 Black/orange72 Low oil pressure warning indicatorPink/white73 Overheat warning indicatorPink/black74 Diagnostic indicator Blue/white75 Electronic throttle valve groundBlack76 ECM ground Black77 Oil control valve (PORT)Purple78 Engine stop lanyard switchWhite79 Electronic throttle valve power sourceRed/green80 Electronic throttle valve power sourceRed/green81 Electronic throttle valve motorGreen/black8283 Electronic throttle valve motorGreen/red84 Electronic throttle valve groundBlack85 Vapor shut-off valve Green/black86 Oil control valve (STBD)PurpleNo.Connecting part Color code6P23H11 1-22123456789Electronic fuel injection control systemIn the F250/FL250 engine, the electronic fuel injection control system controls the fuel injection tim-ing and volume. Maximum output, low fuel consumption, and low emissions are achieved by main-taining the optimum air-fuel ratio under various engine operating conditions.Fuel injection control Description Control Engine conditionInjection timing Simultaneouslyinjectsintocylindergroups#1 and #4, #2 and #5, and #3 and #6.StartingSequential injection in order of cylinders #1,#2, #3, #4, #5, and #6.Normal operationInjection volume Controlstheoperationtimeoftheinjectorsaccordingtotheatmosphericpressureandintake air temperature.From cranking to startingControlstheoperationtimeoftheinjectorsaccordingtotheatmosphericpressure,intake air temperature, and engine tempera-ture.Normal operationStops injection. Turned offAsynchronous injectionSimultaneouslyinjectsintoallcylinderstoprevent a lean air-fuel ratio.Accelerated operating speedsFeature and benefitGEN INFOGeneral information1-23 6P23H11Electronic fuel injection system diagramFuel flows through the fuel filter in the water separator and the low-pressure fuel pump sends thefuel through the fuel filter and is sent to the vapor separator tank. When the fuel in the vapor separa-tortankexceedsthespecifiedvolume,it returnstothelow-pressurefuelpumpviathe fuelhose.Fuel in the vapor separator tank that is pressurized by the high-pressure fuel pump is sent to theport and starboard fuel rails and is injected from the fuel injectors into the combustion chambers.Whenthefuelpressureexceedsthespecifiedvalue,thefuelissentbacktothevaporseparatortank from the pressure regulator via the fuel cooler to maintain the specified fuel pressure.When the engine is turned off and when the engine is cranked, the vapor shut-off valve closes toprevent the fuel vapor gas from entering the surge tank. After the engine is started, the vapor shut-offvalveopensandclosesrepeatedlytocontrolthefuelvaporgasvolumethatentersthesurgetank.When the vapor shut-off valve is closed, the fuel vapor gas is adsorbed by the activated carbon inthe canister and some is released into the atmosphere.S6P21116: :: Primer pump Inboard fuel filter (optional) Boat fuel tankFuel filter with water separatorCheck valveLow-pressure fuel pumpCheck valveCheck valveIntake silencerAtmosphereCanisterFilterVapor Separator tankHigh-pressure fuel pumpFuel coolerVapor shut-off valveSurge tankPressure regulatorFuel rail (STBD) Fuel rail (PORT)Injector #1Injector #3Injector #5Injector #6Injector #4Injector #2Combustion chamber #1Combustion chamber #3Combustion chamber #5Combustion chamber #6Combustion chamber #4Combustion chamber #2Intake manifold (STBD) Intake manifold (PORT)AirFuelVapor gas6P23H11 1-24123456789Circuit diagramS6P21160 +165585565758605915325149361712133472778182348403844413147504515V5V5V5V5V5V5VCrank position sensorCam position sensor (PORT EX)Cam position sensor (PORT IN)Cam position sensor (STBD IN)TPS 1TPS 2GroundAccelerator position sensor 1Accelerator position sensor 2GroundIntake air pressure sensorGroundIntake air temperature sensorEngine temperature sensorNeutral switchGroundEngine stop lanyard switchMain relayEngine start switchBatteryFuel injector #1Fuel injector #2Fuel injector #3Fuel injector #4Fuel injector #5Fuel injector #6Vapor shut-off valveECMFeature and benefitGEN INFOGeneral information1-25 6P23H11Ignition timing control systemIntheF250/FL250engine,theignitiontimingcontrolsystemcontrolstheignitiontimingandthepower supply timing to the ignition coils.Maximum output, low fuel consumption, and low emissions are achieved by securing the optimumignition timing under various engine operating conditions.Ignition timing controlIgnition timing when cranking and starting the engineWhen the engine is cranked and started, the spark plug ignites at BTDC 10.Ignition at normal operationDuringnormaloperation,mapcontrolisperformedaccordingtotheenginespeed,theintakeairpressure, and the octane value of the fuel. The power supply timing to the ignition coils is controlledby the battery voltage.Description Control Engine conditionIgnition timing Stops ignition. Turned offSimultaneous ignition for cylinder groups #1and #4, #2 and #5, and #3 and #6.Cranking and startingSequentialignitioninorderofcylinders#1,#2, #3, #4, #5, and #6.Normal operationPower supply timing Controls the power supply timing to the igni-tion coils.Normal operation6P23H11 1-26123456789Circuit diagramS6P211705VECM +1653546263707115325149361761334727788182348403844413147504515V5V5V5V5V5VECMCrank position sensorCam position sensor (PORT EX)Cam position sensor (PORT IN)Cam position sensor (STBD IN)TPS 1TPS 2GroundAccelerator position sensor 1Accelerator position sensor 2GroundIntake air pressure sensorGroundIntake air temperature sensorEngine temperature sensorShift cut switchGroundEngine start switchEngine stop lanyard switchBatteryMain relayIgnition coil #1Ignition coil #2Ignition coil #3Ignition coil #4Ignition coil #5Ignition coil #6Knock sensorFeature and benefitGEN INFOGeneral information1-27 6P23H11Knock control systemIn the F250/FL250 engine, the knock sensor detects the engine knock that occurs due to abnormalcombustionduringoperationanddetermineswhetherthereisengineknockanditssize.Whenengineknockisdetermined,theknockcontrolsystemretardstheignitiontimingtopreventtheoccurrence of engine knock.Knock controlDescription Control Engine conditionKnock Detectswhetherengineknockoccursatignition. When engine knock is detected, theignition timing is retarded by a fixed amount.When the engine speed ishigher than the engine idlespeedafterwarmingtheengine up.6P23H11 1-28123456789Circuit diagramS6P211801653546263707115513681848475045347275V5VIgnition coil #1Ignition coil #2Ignition coil #3Ignition coil #4Ignition coil #5Ignition coil #6Crank position sensorTPS 1TPS 2GroundIntake air pressure sensorGroundKnock sensorMain relayECMFeature and benefitGEN INFOGeneral information1-29 6P23H11Variable camshaft timing control systemIn the F250/FL250 engine, the opening and closing timing of the intake valves is controlled.TheECMoperatestheoilcontrolvalveaccordingtotheenginespeedandtheelectronicthrottlevalve opening angle and controls the optimum opening and closing timing of the intake valves. Max-imum output is achieved by increasing the volumetric efficiency of the combustion chambers undervarious engine operating conditions.Variable camshaft timing controlVariable camshaft timing control diagramThe ECM determines the intake valve opening and closing timing suitable for the operating condi-tions according to the engine speed, electronic throttle valve opening angle, and engine tempera-ture.Inaddition,theexhaustandintakecampositionsensorsdetecttheactualadvancepositionand perform feedback control of the oil control valve to reach the target advance position.The ECM sends a signal to the oil control valve to switch the oil passage to send engine oil to theadvance chamber or retard chamber in the rotor vane housing. According to the engine oil pressurein the respective chamber, the rotor vane operates to advance or retard the camshaft that is con-nected to the rotor vane.Description Control Engine conditionVariable camshaft timing Setstheadvancetargetangleaccordingto the engine speed and electronic throttlevalve opening. Detectstheexhaustandintakecamshaftpositions, operates the oil control valve toreachtheadvancetargetangle,andcon-trols the optimum opening and closing tim-ing of the intake valves.At mid-speed range, oper-ates to the advance angle,andatengineidlespeedandthefullyopenrange,operatestotheretardangle.S6P21113(PORT EX) (PORT IN)Rotor vane housing(STBD IN)Rotor vane housingAdvance/Retard directionAdvance/Retard directionSensor signalOil control valve Oil flowOil control valve Drive signalAdvance Retard Retard AdvanceCam CamCam position sensorEngine temperature sensorCrank position sensorTPSECMReturnOil filter Oil pumpOil panReturnCamCam position sensorCam position sensor6P23H11 1-30123456789Oil control valve operationWhen the camshaft advances, the spool valve moves toward the coil spring according to the mag-netic force of the magnetic coil, the spring is compressed, and the engine oil is sent to the advancechamber passage. The engine oil in the retard chamber returns to the oil pan via the spool valvepassage.When the camshaft retards, the spool valve moves toward the magnetic coil according to the mag-neticforceofthemagneticcoilandtheforceofthecoilspring,andtheengineoilissenttotheretard chamber passage. The engine oil in the advance chamber returns to the oil pan via the spoolvalve passage.1 Coil spring2 Magnetic coil Advance Retard Advance oil flow Retard oil flow Operation direction of spool valve Oil return Oil supplyS6P21190 1122Feature and benefitGEN INFOGeneral information1-31 6P23H11Rotor vane operationThe variable camshaft timing unit consists of a rotor vane and rotor vane housing. The rotor vane isfastenedtotheintakecamshaftwithabolt,whichallowsthemtorotatetogether.Therotorvanehousing is fastened to the driven sprocket of the intake camshaft with a bolt, which allows them torotate together.The rotor vane in the rotor vane housing is operated by the engine oil pressure to advance or retardthe camshaft. When the engine is started, the engine oil pressure is low and the rotor vane is fixedtothehousingbya lockpin.Aftertheengineisstarted,theengine oil pressure increasesastheengine speed increases and the engine oil enters the advance chamber in the housing and the lockpin is released. When the camshaft advances, the engine oil that entered the advance chamber inthe housing moves the rotor vane to the advance direction, and the engine oil in the retard chamberpasses through the spool valve and returns to the oil pan. When the camshaft retards, the engine oilenters the retard chamber in the housing and moves the rotor vane to the retard direction, and theengine oil in the advance chamber passes through the spool valve and returns to the oil pan.1 Rotor vane2 Rotor vane housing3 Bolt4 Retard passage5 Drive sprocket (IN)6 Camshaft7 Advance port8 Retard port9 Advance chamber0 Lock pinA SealB Retard chamberC Advance passageD Spring Rotation direction of variable camshaft timingS6P211154D03256C78A0192B16P23H11 1-32123456789Circuit diagramS6P212005V16778615325117184750451347275VCrank position sensorCam position sensor (PORT EX)Cam position sensor (PORT IN)Cam position sensor (STBD IN)TPS 1TPS 2GroundEngine temperature sensorGroundMain relayECMOil control valve (STBD)Oil control valve (PORT)Feature and benefitGEN INFOGeneral information1-33 6P23H11Electronic throttle valve control systemIntheF250/FL250engine,theelectronicthrottlevalvecontrolsystemconvertstheopeningandclosingoftheremotecontrolleveracceleratortoanelectronicsignalandtheECMcontrolsthethrottle valves according to the operating condition of the accelerator opening.Electronic throttle valve controlElectronic throttle valve operationA cable transmits the operation of the remote control lever to the accelerator position sensor, whichconverts the accelerator lever opening angle to an electronic signal. The ECM uses this signal to setthe target opening angle of the throttle valve. At the same time, the TPS detects the throttle valveopening angle and checks the difference to that of the target opening angle. Then, the ECM sendsan electronic signal to the electronic throttle valve motor and performs feedback control of the differ-ence of the target opening angle and throttle valve opening angle.1 Remote control box2 Accelerator position sensor3 Accelerator lever4 ECM5 Electronic throttle valve assembly (TPS)6 Electronic throttle valve motor Throttle cable Sensor signalDescription Control Engine conditionSetting of the target throttle valve openingDetectstheacceleratorsensorsignalandthe ECM sets the target throttle valve open-ing.Startingandnormaloper-ation.Throttle valve opening feedbackChecksthedifferencebetweenthesignalfromtheTPSandthetargetthrottlevalveopeningandperformsfeedbackcontrolonthe throttle valve opening.Startingandnormaloper-ation.Engine idle speed Controlsthethrottlevalveopeningtostabi-lizetheenginespeedatidlewhilecontrol-ling the intake air volume.Operationatengineidlespeed.Limp home processing (electronic throttle valve fail-safe)Fixes the throttle valve opening to the speci-fiedopeningangleandcontrolstheignitiontimingcontrolaccordingtotheacceleratorposition sensor opening angle. The engine idle speed isincreased and stabilized. Theenginespeedisfixed even if the acceler-ator lever is opened.S6P21121 1 2 5 4 366P23H11 1-34123456789Circuit diagramS6P21210 +5583758481668079565758605951491761271334271840384441314750455V5V5V5V5V5VTPS 1TPS 2GroundAccelerator position sensor 1Accelerator position sensor 2GroundGroundEngine temperature sensorShift cut switchGroundEngine start switchBatteryMain relayNeutral switchECMFuel injector #1Fuel injector #2Fuel injector #3Fuel injector #4Fuel injector #5Fuel injector #6Electronic throttle valve relayElectronic throttle valve motorFeature and benefitGEN INFOGeneral information1-35 6P23H11Engine speed control system In the F250/FL250 engine, the engine speed control system decreases the engine speed to protectthe engine from damage when the engine overheats or when the engine oil pressure is low.Engine speed controlDescription Control Engine conditionOverheat Detectswhentheengineoverheatsandcontrols the engine speed. Detectsthattheengineisoverheatingwhenthethermoswitchisturnedon or the engine temper-atureexceeds120C(248 F). TheECMcausesthecylinderstomisfire,cutsoffinjection,decreasesthe engine speed to lessthan2,000r/min,acti-vatesthewarningbuzz-er,andturnstheover-heatwarningindicatoron.Low oil pressure Detects when the engine oil pressure is lowand controls the engine speed. Detectsthattheengineoilpressureislowwhenthe oil pressure decreas-es to less than the speci-fiedvaluefortheenginespeed range. TheECMcausesthecylinderstomisfire,cutsoffinjection,decreasesthe engine speed to lessthan2,000r/min,acti-vatesthewarningbuzz-er,andturnsthelowoilpressure warning indica-tor on.DES DetectsthestatusoftheDEScontrolandcontrols the engine speed. Whentheoverheatwarningorlowoilpres-surewarningisacti-vated, the DES switch isturnedonandthewarn-ing buzzer is activated. Whenthisoccurs,theECMcausesthecylin-derstomisfire,injectionis cut off, and the enginespeed decreases to lessthan 2,000 r/min.6P23H11 1-36123456789Shift cut Detects the status of the shift cut control andcontrols the engine speed.Twocylindersmisfireandthe engine speed decreas-es so that the shift can beshifted.Over-revolution Detectsthestatusoftheover-revolutioncontrol and controls the engine speed. Whentheengineoverrevsandtheenginespeedexceeds6,449r/min,allcylindersmis-fire. Whentheengineoverrevsandtheenginespeedexceeds6,199r/minandis6,449r/minorless,cylinders#2to#5, #3, and #6 misfire fora short time. Normaloperationwhentheenginespeedis6,199 r/min or less.Description Control Engine conditionFeature and benefitGEN INFOGeneral information1-37 6P23H11Circuit diagramS6P21220 +BZ165572677353546263707156575860591551175261334271837484750455V5V5V5V7Crank position sensorTPS 1TPS 2GroundOil pressure sensorEngine temperature sensorThermoswitchShift cut switchGroundEngine start switchBatteryMain relayFuel injector #1Fuel injector #2Fuel injector #3Fuel injector #4Fuel injector #5Fuel injector #6Ignition coil #1Ignition coil #2Ignition coil #3Ignition coil #4Ignition coil #5Ignition coil #6Low oil pressure warning indicatorOverheat warning indicatorBuzzer (DES switch)DES switchECM6P23H11 1-38123456789Lower unitA spring has been added to the lower unit for the F250/FL250The spring is used to push the drive shaft toward the water pump and stabilize the thrust free play ofthe shaft.This spring facilitates the backlash measurement procedure since the lower unit does not need tobe turned upsidedown to carry out the measurement.1 Shim2 Thrust bearing3 Drive shaft4 Spring5 Washer Water pump sideS6P21126CFeature and benefitGEN INFOGeneral information1-39 6P23H11Propeller selection 1Theperformanceofaboatandoutboardmotorwillbecriticallyaffectedbythesizeand type of propeller you choose. Propellersgreatlyaffectboatspeed,acceleration,enginelife,fueleconomy,andevenboatingand steering capabilities. An incorrect choicecouldadverselyaffectperformanceandcould also seriously damage the engine. Usethefollowinginformationasaguideforselecting a propeller that meets the operatingconditionsoftheboatandtheoutboardmotor.Propeller sizeThesizeofthepropellerisindicatedonthepropeller boss end, on the side of the propel-ler boss.a Propeller diameter (in inches)b Propeller pitch (in inches)c Propeller type (propeller mark)SelectionWhentheenginespeedisatthefullthrottleoperatingrange(5,0006,000r/min),theidealpropellerfortheboatisonethatpro-videsmaximumperformanceinrelationtoboat speed and fuel consumption.Regular rotation modelCounter rotation modelS69J1100- S6P21100 - bacPropeller size (in) Material13 3/4 17 - M2Stainless13 3/4 19 - M213 3/4 21 - M14 1/2 15 - M14 1/2 19 - T14 1/2 21 - T14 1/2 23 - M14 7/8 21 - M15 17 - T15 21 - T15 1/4 15 - M15 1/4 17 - M15 1/4 19 - M15 1/4 19 - T15 1/2 17 - TPropeller size (in) Material13 3/4 17 - ML1Stainless13 3/4 19 - ML113 3/4 21 - ML14 1/2 19 - TL14 1/2 21 - TL14 1/2 23 - ML14 7/8 21 - ML15 17 - TL15 21 - TL15 1/4 15 - ML15 1/4 17 - ML15 1/4 19 - ML15 1/4 19 - TL15 1/2 17 - TL6P23H11 1-40123456789Predelivery check 1Tomakethedeliveryprocesssmoothandefficient,thepredeliverychecksshouldbecompleted as explained below.Checking the fuel system1. Checkthatthefuelhosesaresecurelyconnectedandthatthefueltankisfullwith fuel.CAUTION:Thisisa4-strokeengine.Neverusepre-mixed fuel or 2-stroke outboard motor oil.Checking the engine oil level1. Check the engine oil level.NOTE:Iftheengineoilisbelowtheminimumlevelmark(L),addsufficientoiluntilthelevelisbetween (H) and (L).Checking the gear oil level1. Check the gear oil level.Checking the battery1. Check the capacity, electrolyte level, andspecified gravity of the battery.2. Check that the positive and negative bat-tery cables are securely connected. Recommended engine oil:4-stroke motor oilAPI: SE, SF, SG, SH, SJ, or SLSAE: 5W-30, 10W-30, or 10W-40Engine oil quantity:Without oil filter replacement:5.6 L (5.92 US qt, 4.93 Imp qt)Recommended battery capacity:CCA/EN: 711 A20HR/IEC: 100 AhElectrolyte specified gravity:1.280 at 20 C (68 F)S60C1140Propeller selection / Predelivery checkGEN INFOGeneral information1-41 6P23H11Checking the outboard motor mounting height1. Checkthattheanti-cavitationplateisaligned with the bottom of the boat. If themountingheightistoohigh,cavitationwill occur and propulsion will be reduced.Also,theenginespeedwillincreaseabnormallyandcausetheenginetooverheat.Ifthemountingheightistoolow,waterresistancewillincreaseandreduce engine efficiency.NOTE:Theoptimummountingheightisaffectedbythe combination of the boat and the outboardmotor.Todeterminetheoptimummountingheight,testruntheoutboardmotoratdiffer-ent heights.2. Checkthattheclampbracketsaresecured with the clamp bolts.Checking the remote control cable1. Settheremotecontrollevertotheneu-tralpositionandfullyclosethethrottlelever.2. Checkthattheacceleratorlever1con-tacts the fully closed stopper 2.NOTE:Toadjustthethrottlecable,seeChapter3,Adjusting the throttle cable.3. Check that the center of the set pin a isalignedwiththealignmentmarkbonthe bracket. WARNINGTheshift/throttlecablejointmustbescrewed in a minimum of 8.0 mm (0.31 in)c.21S6P21030S69J33706P23H11 1-42123456789Checking the steering system1. Checkthatthesteeringoperatessmoothly.2. Checkthatthereisnointerferencewithwires or hoses when the outboard motoris steered.Checking the gear shift and throttle operation1. Checkthatthegearshiftoperatessmoothlywhentheremotecontrolleveris shifted from the neutral position to for-ward or reverse.2. Check that the throttle operates smoothlywhentheremotecontrolleverisshiftedfrom forward or reverse to the fully openposition a.Checking the PTT system1. CheckthattheoutboardmotortiltsupanddownsmoothlywhenoperatingthePTT unit. 2. Checkthatthereisnoabnormalnoiseproducedwhentheoutboardmotoristilted up or down.3. Checkthatthereisnointerferencewithwiresorhoseswhenthetilted-upout-board motor is steered.4. Checkthatthetrimmeterpointsdownwhentheoutboardmotoristiltedalltheway down.Checking the engine start switch and engine stop lanyard switch1. Checkthattheenginestartswhentheengine start switch is turned to START.2. Check that the engine turns off when theengine start switch is turned to OFF.3. Check that the engine turns off when theenginestoplanyardispulledfromtheengine stop lanyard switch.NF RaaS6P21070OFFONSTARTOFFONSTARTS6P21080S6P21090EPredelivery checkGEN INFOGeneral information1-43 6P23H11Checking the cooling water pilot hole1. Start the engine, check that cooling wateris discharged from the cooling water pilothole.Test run1. Start the engine, and then check that thegear shift operates smoothly.2. Checktheengineidlespeedaftertheengine has been warmed up.3. Operate at trolling speed.4. Runtheoutboardmotorfor1hourat2,000r/minorathalfthrottle,thenforanotherhourat3,000r/minorat3/4throttle.5. Checkthattheoutboardmotordoesnottilt up when shifting into reverse and thatwater does not flow in over the transom.NOTE:The test run is part of the break-in operation.Break-inDuringthetestrun,performthebreak-inoperation in the following three stages.1. 1houraat2,000r/minoratapproxi-mately half throttle2. 1hourbat3,000r/minor3/4throttleand 1 minute out of every 10 at full throt-tle3. 8 hours c at any speed, however, avoidrunning at full speed for more than 5 min-utes HourAfter test run1. Check for water in the gear oil.2. Check for fuel leakage in the cowling.3. Flushthecoolingwaterpassagewithfresh water using the flushing kit and withthe engine running at idle.CAUTION:Besuretosupplysufficientwaterandwater pressure when flushing the coolingwater passage. If sufficient water and suf-ficientwaterpressurearenotsupplied,the engine can overheat.S6P21050S69J12400 1 2 10 a b c6P23H11SPEC123456789SpecificationGeneral specification..................................................................................... 2-1Maintenance specification ............................................................................ 2-3Power unit.................................................................................................. 2-3Lower unit .................................................................................................. 2-6Electrical .................................................................................................... 2-7Dimension................................................................................................ 2-10Tightening torque......................................................................................... 2-12Specified torque....................................................................................... 2-12General torque......................................................................................... 2-15SPECSpecification2-1 6P23H11General specification 2Item UnitModelF250AET FL250AETDimensionOverall length mm (in) 892 (35.1)Overall width mm (in) 634 (25.0)Overall height(X) mm (in) 1,829 (72.0)(U) mm (in) 1,956 (77.0)Boat transom height(X) mm (in) 635 (25.0)(U) mm (in) 762 (30.0)Weight(with stainless propeller)(X) kg (lb) 278.0 (613)(U) kg (lb) 284.0 (626)PerformanceMaximum output kW (hp) 183.9 (250) at 5,500 r/minFull throttle operating range r/min 5,0006,000Maximum fuel consumption L (US gal, Imp gal)/hr81.0 (21.4, 17.8) at 6,000 r/minEngine idle speed r/min 600700Power unitType 4-stroke, DOHCCylinder quantity V6Total displacement cm3 (cu. in) 3,352 (204.5)Bore stroke mm (in) 94.0 80.5 (3.70 3.17)Compression ratio 9.9Control system Remote controlStarting system ElectricFuel system Fuel injectionIgnition control system TCIAdvance type Micro computerMaximum generator output V, A 12, 46Spark plug LFR6A-11 (NGK)Firing order 123456 (Normal operation)Cooling system WaterExhaust system Propeller bossLubrication system Wet sump6P23H11 2-2123456789(*1)If the recommended engine oil grades are not available, use engine oil with an SAE classification of 15W-40, 20W-40, or 20W-50 and an API classification of SH, SJ, or SL.(*2)Meeting both API and SAE requirementsFuel and oilFuel type Premium unleaded gasolineFuel minimum rating RONPON9489Engine oil 4-stroke motor oilEngine oil grade(*1)APISAESE, SF, SG, SH, SJ, or SL5W-30, 10W-30, or 10W-40Engine oil quantity(without oil filter replacement) L (US qt, Imp qt)5.6 (5.92, 4.93)(with oil filter replacement) L (US qt, Imp qt)5.8 (6.13, 5.10)Gear oil type Hypoid gear oilGear oil grade(*2)API GL-4SAE 90Gear oil quantity cm3 (US oz, Imp oz)1,150 (38.9, 40.6) 1,000 (33.8, 35.3)Bracket unitTrim angle (at 12 boat transom)Degree 3 to 16Tilt-up angle Degree 70Steering angle Degree 32 + 32Drive unitGear shift positions F-N-RGear ratio 2.00 (30/15)Reduction gear type Spiral bevel gearClutch type Dog clutchPropeller shaft type SplinePropeller direction (rear view) Clockwise CounterclockwisePropeller mark T, M TL, MLElectricalBattery minimum capacityCCA/EN A 71120HR/IEC Ah 100Item UnitModelF250AET FL250AETGeneral specificationSPECSpecification2-3 6P23H11Maintenance specification 2Power unitItem UnitModelF250AET FL250AETPower unitMinimum compression pressure(*1) kPa (kgf/cm2, psi)740 (7.4, 107.3)Oil pressure(*2)kPa (kgf/cm2, psi)600 (6.0, 87.0) at 60 C (140 F) with SL 10W-30 engine oil and at 900 r/minCylinder headWarpage limit mm (in) 0.1 (0.0039)(lines indicate straightedge position)Camshaft cap inside diameter mm (in) 25.00025.021 (0.98430.9851)CylinderBore size mm (in) 94.00094.017 (3.70083.7014)PistonPiston diameter (D) mm (in) 93.92193.941 (3.69773.6985)Measuring point (H) mm (in) 5.0 (0.20)Piston clearance(*3)mm (in) 0.0750.080 (0.00300.0031)Piston pin boss bore mm (in) 21.01721.031 (0.82740.8280)Piston pinOutside diameter mm (in) 20.99521.000 (0.82660.8268)Piston ringTop ringDimension B mm (in) 1.171.19 (0.0460.047)Dimension T mm (in) 2.803.00 (0.1100.118)End gap(*3)mm (in) 0.150.30 (0.0060.012)Side clearance mm (in) 0.040.08 (0.0020.003)2nd piston ringDimension B mm (in) 1.171.19 (0.0460.047)Dimension T mm (in) 3.703.90 (0.1460.154)End gap(*3)mm (in) 0.300.45 (0.0120.018)Side clearance mm (in) 0.030.07 (0.0010.003)(*1)Measuring conditions:Ambient temperature 20 C (68 F), wide open throttle, with spark plugs removed from all cylinders.The figures are for reference only.(*2)For details of the checking method, see Chapter 5, Checking the oil pressure.The figures are for reference only.(*3)The figures are for reference only.6P23H11 2-4123456789Oil ringDimension B mm (in) 2.402.47 (0.0940.097)Dimension T mm (in) 2.302.70 (0.0910.106)End gap(*1)mm (in) 0.150.60 (0.0060.024)Side clearance mm (in) 0.040.13 (0.0020.005)CamshaftIntake (A) mm (in) 46.3046.40 (1.8231.827)Exhaust (A) mm (in) 45.3545.45 (1.7851.789)Intake and exhaust (B)mm (in) 35.9536.05 (1.4151.419)Camshaft journal diameter mm (in) 24.9624.98 (0.98260.9834)Camshaft runout limit mm (in) 0.015 (0.0006)ValveValve clearance (cold)Intake mm (in) 0.20 0.03 (0.008 0.001)Exhaust mm (in) 0.34 0.03 (0.013 0.001)Head diameter (A)Intake mm (in) 36.436.6 (1.431.44)Exhaust mm (in) 31.431.6 (1.241.24)Face width (B)Intake mm (in) 2.352.78 (0.0920.110)Exhaust mm (in) 2.133.30 (0.0840.130)Seat contact width (C)Intake mm (in) 1.101.40 (0.0430.055)Exhaust mm (in) 1.401.70 (0.0550.067)Margin thickness (D)Intake mm (in) 0.500.90 (0.0200.035)Exhaust mm (in) 0.901.30 (0.0350.051)Stem diameterIntake mm (in) 5.4775.492 (0.21560.2162)Exhaust mm (in) 5.4645.479 (0.21510.2157)Guide inside diameterIntake and exhaust mm (in) 5.5045.522 (0.21670.2174)Stem-to-guide clearanceIntake mm (in) 0.0120.045 (0.00050.0018)Exhaust mm (in) 0.0250.058 (0.00100.0023)Stem runout limit mm (in) 0.01 (0.0004)Valve springFree length mm (in) 44.2 (1.74)Tilt limit mm (in) 1.2 (0.05)(*1)The figures are for reference only.Item UnitModelF250AET FL250AETMaintenance specificationSPECSpecification2-5 6P23H11Valve lifterValve lifter outside diameter mm (in) 32.98232.997 (1.29851.2991)Valve lifter-to-cylinder head clearancemm (in) 0.0200.055 (0.00080.0022)Valve shimValve shim thickness (in 0.020 mm increments)mm (in) 2.3202.960 (0.09130.1165)Connecting rodSmall end inside diameter mm (in) 21.01721.031 (0.82740.8280)Big end inside diameter mm (in) 53.01553.035 (2.08722.0880)Big end side clearance(*1)mm (in) 0.150.30 (0.0060.012)Crankpin oil clearance mm (in) 0.0280.066 (0.00110.0026)Big end bearing thicknessYellow mm (in) 1.4921.496 (0.05870.0589)Green mm (in) 1.4961.500 (0.05890.0591)Blue mm (in) 1.5001.504 (0.05910.0592)CrankshaftCrankshaft journal diameter mm (in) 62.96862.992 (2.47912.4800)Crankpin diameter mm (in) 49.97650.000 (1.96761.9685)Crankpin width mm (in) 21.5021.55 (0.84650.8484)Runout limit mm (in) 0.03 (0.0012)CrankcaseCrankshaft journal oil clearancemm (in) 0.0250.050 (0.00100.0020)Upper crankcase main bearing thickness1 mm (in) 2.4942.500 (0.09820.0984)2 mm (in) 2.4982.504 (0.09830.0986)3 mm (in) 2.5022.508 (0.09850.0987)Lower crankcase main bearing thickness1 mm (in) 2.4942.500 (0.09820.0984)2 mm (in) 2.4982.504 (0.09830.0986)3 mm (in) 2.5022.508 (0.09850.0987)Lower crankcase main bearing thickness (J3)1 mm (in) 2.4922.500 (0.09810.0984)2 mm (in) 2.4962.504 (0.09830.0986)3 mm (in) 2.5002.508 (0.09840.0987)Thrust bearing thickness (J3) mm (in) 1.9071.957 (0.07510.0770)(*1)The figures are for reference only.Item UnitModelF250AET FL250AET6P23H11 2-6123456789Lower unitThermostatOpening temperature C (F) 5862 (136144)Fully open temperature C (F) 70 (158)Valve open lower limit mm (in) 4.3 (0.17)Item UnitModelF250AET FL250AETGear backlashPinion-to-forward gear mm (in) 0.320.55(0.01260.0217)0.460.82(0.01810.0323)Pinion-to-reverse gear mm (in) 0.320.65(0.01260.0256)0.450.78(0.01770.0307)Propeller shaft free play mm (in) 0.200.50(0.00790.0197)0.250.35(0.00980.0138)Pinion shims mm 0.10, 0.12, 0.15, 0.18, 0.30, 0.40, 0.50Forward gear shims mm 0.10, 0.12, 0.15, 0.18, 0.30, 0.40, 0.50Reverse gear shims mm 0.10, 0.12, 0.15, 0.18, 0.30, 0.40, 0.50Propeller shaft shims mm 1.80, 1.90, 2.00, 2.10, 2.200.10, 0.12, 0.15, 0.18, 0.30, 0.40, 0.50Item UnitModelF250AET FL250AETMaintenance specificationSPECSpecification2-7 6P23H11ElectricalItem UnitModelF250AET FL250AETIgnition and ignition control systemSpark plug gap mm (in) 1.01.1 (0.0390.043)Crank position sensor output peak voltage(W/B B)at cranking (unloaded) V 3.0at cranking (loaded) V 2.7at 1,500 r/min (loaded) V 14.5at 3,500 r/min (loaded) V 17.8Crank position sensor resistance(*1)(W/R B)396594Crank position sensor air gap mm (in) 1.41.6 (0.0550.063)Knock sensor resistance k504616Intake air temperature sensor resistanceat 20 C (68 F) k2.212.69Engine temperature sensor resistance (B/Y B/Y)at 20 C (68 F) k54.269.0at 100 C (212 F) k3.123.48Electronic throttle valve control systemTPS output voltage(*1) at 20 C (68 F)with remote control lever fully closedSensor 1 V 0.750with remote control lever fully openSensor 2 V 4.550Electronic throttle valve motor resistance(*1) at 2030 C (6886 F) 1.231.67Accelerator position sensor output voltage(*1)(P B)with remote control lever fully closedSensor 1 V 0.5500.850Sensor 2 V 0.4001.000with remote control lever fully openSensor 1 and 2 V Above 3.250(*1)The figures are for reference only.6P23H11 2-8123456789Accelerator position sensor resistance(*1) at 20 C (68 F)with accelerator lever fully closedk0.800with accelerator lever fully openk5.300Variable camshaft timing control systemOil control valve resistance at 20 C (68 F) 6.77.7Fuel control systemFuel injector resistance(*1)at 21 C (70 F) 12.0Starter motorType Sliding gearOutput kW 1.40Cranking time limit Second 30BrushesStandard length mm (in) 15.5 (0.61)Wear limit mm (in) 9.5 (0.37)CommutatorStandard diameter mm (in) 29.0 (1.14)Wear limit mm (in) 28.0 (1.10)Standard undercut mm (in) 0.8 (0.03)Wear limit mm (in) 0.2 (0.01)Charging systemFuse A 80Stator coil output peak voltage (G G)at cranking (unloaded) V 8.3at 1,500 r/min (unloaded) V 44.7at 3,500 r/min (unloaded) V 97.7Stator coil resistance(*1) (G G)at 20 C (68 F) 0.11440.1716Rectifier Regulator output peak voltage (R Ground)at 1,500 r/min (unloaded) V 13.0at 3,500 r/min (unloaded) V 13.0(*1)The figures are for reference only.Item UnitModelF250AET FL250AETMaintenance specificationSPECSpecification2-9 6P23H11PTT systemTrim sensorSetting resistance 10 1Resistance 9387.6Fluid type ATF Dexron IIMotor brushesStandard length mm (in) 11.5 (0.45)Wear limit mm (in) 4.5 (0.18)Motor commutatorStandard diameter mm (in) 23.0 (0.91)Wear limit mm (in) 22.0 (0.87)Standard undercut mm (in) 1.40 (0.055)Wear limit mm (in) 0.90 (0.035)Item UnitModelF250AET FL250AET6P23H11 2-10123456789DimensionExteriorS6P22020mm (in)453 (17.8)317 (12.5)723.9 (28.5)X: 1,155 (45.5)U: 1,272 (50.1)X: 643 (25.3)U: 770 (30.3)X: 1,078 (42.4)U: 1,205 (47.4)X: 52 (2.0)U: 59 (2.3)X: 847 (33.3)U: 924 (36.4)619 (24.4)219 (8.6)230 (9.1)45 (1.8)387 (15.2)752 (29.6)902 (35.5)39 (1.5)216 (8.5)25 (1.0)673 (26.5)59 (2.3)75 (3.0)651 (25.6)3212367Maintenance specificationSPECSpecification2-11 6P23H11Clamp bracketmm (in)79 (3.1)13 (0.5)180 (7.1)163.5 (6.4)254 (10.0)55.5 (2.2)411 (16.2)163.5 (6.4)125.4 (4.9) 125.4 (4.9)101.5 (4.0) 101.5 (4.0)180 (7.1)13 (0.5)50.8 (2.0)18.5 (0.7)S6P220106P23H11 2-12123456789Tightening torque 2Specified torquePart to be tightened Thread sizeTightening torquesNm kgfm ftlbFuel systemFilter cup 3.5 0.35 2.6Intake manifold bolt M6 10 1.0 7.4Intake silencer bolt M6 7 0.7 5.2Electronic throttle valve assembly nut 13 1.3 9.6Throttle damper plate bolt M8 13 1.3 9.6Canister mounting bolt M6 5 0.5 3.7Canister bracket bolt M6 5 0.5 3.7Vapor shut-off valve mounting nut 5 0.5 3.7Intake air pressure sensor bolt M6 5 0.5 3.7Low-pressure fuel pump cover bolt M6 9 0.9 6.6Check valve holder screw M5 4 0.4 3.0Fuel cooler bolt M6 5 0.5 3.7Pressure regulator screw M6 5 0.5 3.7Float chamber cover screw M4 2 0.2 1.5Float chamber cover inner plate screw M4 2 0.2 1.5Float pin screw M4 2 0.2 1.5Vapor separator drain screw 2 0.2 1.5Power unitPower unit mounting bolt M10 42 4.2 31.0Apron bolt M6 8 0.8 5.9Upper case cover bolt M6 8 0.8 5.9PTT motor lead bolt M6 4 0.4 3.0Ignition coil bolt M6 7 0.7 5.2Spark plug 25 2.5 18.4Cooling water pressure sensor adapter plug M14 23 2.3 17.0Flywheel magnet nut 240 24.0 177.0Crank position sensor screw M5 4 0.4 3.0Timing belt tensioner bolt 39 3.9 28.8Timing belt pulley bolt M10 39 3.9 28.8Variable camshaft timing cap 32 3.2 23.6Variable camshaft timing bolt M12 60 6.0 44.3Driven sprocket bolt M10 60 6.0 44.3Cylinder head cover plate screw M4 2 0.2 1.5Camshaft cap bolt1stM78 0.8 5.92nd 17 1.7 12.5Cylinder head cover bolt1stM68 0.8 5.92nd 8 0.8 5.9Positive battery cable bolt M8 18 1.8 13.3Negative battery cable nut 13 1.3 9.6Negative terminal bolt 26 2.6 19.2Maintenance specification / Tightening torqueSPECSpecification2-13 6P23H11ECM bolt M6 7 0.7 5.2PTT relay lead nut 4 0.4 3.0Rectifier Regulator bolt1stM66 0.6 4.42nd 12 1.2 8.9Exhaust cover bolt1stM66 0.6 4.42nd 12 1.2 8.9Exhaust cover plug1stM814 1.4 10.32nd 28 2.8 20.7M18 55 5.5 40.6Anode screw M4 3 0.3 2.2Engine hanger bolt M6 12 1.2 8.9Cylinder head bolt1stM814 1.4 10.32nd 28 2.8 20.71stM1023 2.3 17.02nd 45 4.5 33.23rd Loosen completely4th 23 2.3 17.05th 45 4.5 33.26th 90Knock sensor 32 3.2 23.6Cooling water passage cover bolt M6 12 1.2 8.9Oil filter 18 1.8 13.3Oil pressure sensor 18 1.8 13.3Oil filter joint 34 3.4 25.1Crankcase cover bolt1stM814 1.4 10.32nd 28 2.8 20.7Connecting rod cap bolt1stM923 2.3 17.02nd 43 4.3 31.73rd 90Engine temperature sensor 15 1.5 11.1Crankcase bolt1stM814 1.4 10.32nd 28 2.8 20.71stM825 2.5 18.42nd 901stM1040 4.0 29.52nd 90Oil pump cover screw M6 4 0.4 3.0Thermostat cover plug M14 23 2.3 17.0Lower unit (regular rotation model)Gear oil check screw 9 0.9 6.6Gear oil drain screw 9 0.9 6.6Lower case mounting bolt (nut) M10 47 4.7 34.7Trim tab bolt M10 42 4.2 31.0Propeller nut 54 5.4 39.8Part to be tightened Thread sizeTightening torquesNm kgfm ftlb6P23H11 2-14123456789Grease nipple 6 0.6 4.4Propeller shaft housing bolt M8 30 3.0 22.1Cooling water inlet cover screw M5 4 0.4 3.0Pinion nut 142 14.2 104.7Lower unit (counter rotation model)Gear oil check screw 9 0.9 6.6Gear oil drain screw 9 0.9 6.6Lower case mounting bolt (nut) M10 47 4.7 34.7Trim tab bolt M10 42 4.2 31.0Propeller nut 54 5.4 39.8Ring nut 108 10.8 79.7Grease nipple 6 0.6 4.4Propeller shaft housing bolt M8 30 3.0 22.1Cooling water inlet cover screw M5 4 0.4 3.0Pinion nut 142 14.2 104.7Bracket unitShift cut switch screw M4 2 0.2 1.5Shift cut switch bracket bolt 19 1.9 14.0Neutral switch screw M4 2 0.2 1.5Grease nipple 1 0.1 0.7Shift rod detent bolt 18 1.8 13.3Grease nipple 1 0.1 0.7Flushing hose adapter screw M6 5 0.5 3.7Upper mount bracket bolt M10 54 5.4 39.8Apron stay 8 0.8 5.9Engine oil drain bolt M14 27 2.7 19.9Upper mount nut 72 7.2 53.1Lower mount nut 72 7.2 53.1Oil pan assembly boltM8 20 2.0 14.8M10 42 4.2 31.0PCV 8 0.8 5.9Baffle plate screw M6 4 0.4 3.0Oil strainer bolt M6 10 1.0 7.4Oil pan bolt M8 20 2.0 14.8Exhaust manifold bolt M8 20 2.0 14.8Muffler bolt M8 20 2.0 14.8Friction plate screw M6 4 0.4 3.0Grease nipple 3 0.3 2.2Self- locking nut 22 2.2 16.2Thrust receiver nut 36 3.6 26.6PTT unitReservoir mounting bolt M8 19 1.9 14.0PTT motor mounting bolt M8 19 1.9 14.0Reservoir cap M12 7 0.7 5.2Part to be tightened Thread sizeTightening torquesNm kgfm ftlbTightening torqueSPECSpecification2-15 6P23H11General torqueThischartspecifiestighteningtorquesforstandardfastenerswithastandardISOthread pitch. Tightening torque specificationsforspecialcomponentsorassembliesareprovidedinapplicablesectionsofthisman-ual. To avoid warpage, tighten multi-fastenerassembliesinacrisscrossfashionandpro-gressivestagesuntilthespecifiedtorqueisreached.Unlessotherwisespecified,torquespecifications require clean, dry threads. Components should be at room temperature.Manual valve 2 0.2 1.5Pipe joint 15 1.5 11.1Pipe joint adapter 20 2.0 14.8Gear pump bolt M5 7 0.7 5.2Gear pump bracket bolt M5 7 0.7 5.2Trim cylinder end screw 160 16 118.0Tilt ram 55 5.5 40.6Tilt cylinder end screw 90 9.0 66.4Tilt piston bolt M6 7 0.7 5.2Part to be tightened Thread sizeTightening torquesNm kgfm ftlbNut (A) Bolt (B)General torque specificationsNm kgfm ftlb8 mm M5 5 0.5 3.710 mm M6 8 0.8 5.912 mm M8 18 1.8 13.314 mm M10 36 3.6 26.617 mm M12 43 4.3 31.76P23H11CHK ADJ123456789Periodic check and adjustmentMaintenance interval chart............................................................................ 3-1Top cowling.................................................................................................... 3-3Checking the top cowling........................................................................... 3-3Fuel system.................................................................................................... 3-3Checking the fuel joint and fuel hose (fuel joint-to-fuel injector) ................ 3-3Checking the fuel filter ............................................................................... 3-4Power unit....................................................................................................... 3-4Checking the engine oil ............................................................................. 3-4Changing the engine oil using an oil changer............................................ 3-4Changing the engine oil by draining it ....................................................... 3-5Replacing the oil filter ................................................................................ 3-6Checking the timing belt ............................................................................ 3-6Checking the spark plug............................................................................ 3-7Checking the thermostat............................................................................ 3-7Checking the cooling water passage......................................................... 3-9Control system............................................................................................... 3-9Checking the engine idle speed ................................................................ 3-9Adjusting the throttle cable ...................................................................... 3-10Checking the gear shift operation............................................................ 3-11Bracket unit .................................................................................................. 3-12Checking the PTT operation.................................................................... 3-12Checking the PTT fluid level .................................................................... 3-12Lower unit ..................................................................................................... 3-13Checking the gear oil level ...................................................................... 3-13Changing the gear oil .............................................................................. 3-13Checking the lower unit for air leakage ................................................... 3-14Checking the propeller............................................................................. 3-14General.......................................................................................................... 3-14Checking the anode................................................................................. 3-14Checking the battery................................................................................ 3-15Lubricating the outboard motor................................................................ 3-16CHK ADJPeriodic check and adjustment3-1 6P23H11Maintenance interval chart 3Use the following chart as a guideline for general maintenance.Adjust the maintenance intervals according to the operating conditions of the outboard motor.NOTE:When operating in salt water, turbid or muddy water, the engine should be flushed with clean waterafter each use.Item RemarksInitial EveryRefer to page10 hours (1 month)50 hours (3 months)100 hours (6 months)200 hours (1 year)Anodes (external) Check/replace 3-14Anodes (cylinder head, thermostat cover)Check/replace 3-14Battery Check/charge 3-15Cooling water passages Clean 3-9Top cowling Check 3-3Fuel filter (can be disassembled)Check/replace 3-4Fuel system Check 3-3Gear oil Change 3-13Lubrication points Lubricate 3-16Engine idle speed Check 3-9PCV Check 7-7PTT unit Check 3-12Propeller and cotter pin Check/replace 3-14Shift link/shift cable Check/adjust 3-11Thermostat Check/replace 3-7Throttle link/throttle cable/throttle pick-up timingCheck/adjust 3-10Water pump Check/replace 6-5, 6-35Engine oil Check/change 3-4Oil filter (cartridge) Change 3-6Spark plugs Clean/adjust/replace3-7Timing belt Check/replace 3-66P23H11 3-2123456789Item RemarksEveryRefer to page500 hours (2.5 years)1,000 hours (5 years)Timing belt Replace 5-15Valve clearance (DOHC) Check/adjust 5-10Fuel filter(vapor separator tank)Replace 4-23Oil control valve filter Check/replace 5-41Anodes (exhaust cover, cooling water passage cover, Rectifier Regulator cover)Replace 3-14Exhaust guide, exhaust manifoldCheck/replace 7-8Maintenance interval chartCHK ADJPeriodic check and adjustment3-3 6P23H11Top cowling 3Checking the top cowling1. Checkthefittingbypushingthecowlingwith both hands. Adjust if necessary.2. Loosen the bolts 1.3. Movethehook 2upor down slightlytoadjust its position.NOTE: Toloosenthefitting,movethehookindirection a. Totightenthefitting,movethehookindirection b.4. Tighten the bolts.5. Check the fitting again and, if necessary,repeat steps 24.6. Check the top cowling hoses. Replace ifcracked or damaged.Fuel system 3Checking the fuel joint and fuel hose (fuel joint-to-fuel injector)1. Remove the flywheel magnet cover, portintake manifold, and fuel rail covers.NOTE:See the exploded diagram (4-12, 4-26).2. Checkthelow-pressurefuelhosecon-nections.Also,checkthefuelfilter1,low-pressurefuelpump2,filter3,checkvalve4,andfuelcooler5.Replaceifthereisleakageordeteriora-tion.3. Checkthehigh-pressurefuelhosecon-nections.Also,checkthevaporsepara-tor 6, pressure regulator 7, fuel rails 8,andfuelinjectors9.Replaceifthereisleakage or deterioration.4. Installtheportintakemanifold,fuelrailcovers, and flywheel magnet cover.S6P2302089546312876P23H11 3-4123456789NOTE:To install the intake manifold, see Chapter 4,Installing the intake manifold.Checking the fuel filter1. Check the fuel filter element 1. Replaceif there is dirt or residue.2. Checkthecup2.Cleanwithstraightgasoline if there are foreign substance orreplace if cracked.NOTE:Besurenottospillanyfuelwhenremovingthe fuel filter cup.Power unit 3Checking the engine oil1. Placetheoutboardmotorinanuprightposition.2. Removetheoildipstick,wipeitclean,andtheninsertitbackintothedipstickguide.3. Removetheoildipstickagaintocheckthe oil level, and to check the oil for dis-coloration and its viscosity.NOTE: Change the oil if it appears milky or dirty. If the engine oil is below the minimum levelmark (L), add sufficient oil until the level isbetween (H) and (L).Changing the engine oil using an oil changer1. Starttheengine,warmitup,andthenturn it off.2. Removetheoildipstickandoilfillercap1.3. Insert the tubeof the oilchanger2 intothe dipstick guide 3.4. Operate the oil changer to extract the oil.NOTE:Be sure to clean up any oil spills.Top cowling / Fuel system / Power unitCHK ADJPeriodic check and adjustment3-5 6P23H115. Pour the specified amount of the recom-mended engine oil into the oil filler hole.6. Installtheoilfillercapandoildipstick,and then start the engine and warm it upfor 5 minutes.7. Turntheengineoff,andthenchecktheoil level and that there is no oil leakage. Iftheoillevelislow,addengineoiltothecorrect level.Changing the engine oil by draining it1. Starttheengine,andwarmitup,andthen turn it off.2. Removetheoildipstickandoilfillercap1.3. Remove the starboard apron 2.4. Placeadrainpanunderthedrainhole,and then remove the engine oil drain bolt3 and let the oil drain completely.NOTE:Be sure to clean up any oil spills.5. Install the engine oil drain bolt, and thentighten it to the specified torque.6. Pour the specified amount of the recom-mended engine oil into the oil filler hole.7. Installtheoilfillercapandoildipstick,and then start the engine and warm it upfor 5 minutes.8. Turntheengineoff,andthenchecktheoil level and that there is no oil leakage. Iftheoillevelislow,addengineoiltothecorrect level.9. Installthestarboardapron2,andthentighten the bolts to the specified torque.Recommended engine oil:4-stroke motor oilAPI: SE, SF, SG, SH, SJ, or SLSAE: 5W-30, 10W-30, or 10W-40Engine oil quantity:Without oil filter replacement:5.6 L (5.92 US qt, 4.93 Imp qt)T R..Engine oil drain bolt 3:27 Nm (2.7 kgfm, 19.9 ftlb)Recommended engine oil:4-stroke motor oilAPI: SE, SF, SG, SH, SJ, or SLSAE: 5W-30, 10W-30, or 10W-40Engine oil quantity:Without oil filter replacement:5.6 L (5.92 US qt, 4.93 Imp qt)6P23H11 3-6123456789Replacing the oil filterCAUTION:Donotdamagetheoilpressuresensorand its lead when replacing the oil filter.1. Extract the engine oil with an oil changeror drain it.2. Placearagundertheoilfilter,andthenremove the oil filter using a 72.5 mm (2.9in) oil filter wrench 1.NOTE: Wait more than 5 minutes after turning theengine off to replace the oil filter. Be sure to clean up any oil spills.3. ApplyathincoatofengineoiltotheO-ring of the new oil filter.4. Installtheoilfilter,andthentightenittothespecifiedtorqueusinga72.5mm(2.9 in) oil filter wrench.5. Pour the specified amount of the recom-mended engine oil into the oil filler hole.6. Installtheoilfillercapandoildipstick,and then start the engine and warm it upfor 5 minutes.7. Turntheengineoff,andthenchecktheoil level and that there is no oil leakage. Iftheoillevelislow,addengineoiltothecorrect level.Checking the timing beltCAUTION:Do not turn the flywheel magnet counter-clockwise,otherwisethewaterpumpimpeller may be damaged.1. Remove the flywheel magnet cover.T R..Apron bolt:8 Nm (0.8 kgfm, 5.9 ftlb)Oil filter wrench 1: 90890-06830S6S13220LT572LT572LT572LT57221S6P23080T R..Oil filter: 18 Nm (1.8 kgfm, 13.3 ftlb)Recommended engine oil:4-stroke motor oilAPI: SE, SF, SG, SH, SJ, or SLSAE: 5W-30, 10W-30, or 10W-40Engine oil quantity:With oil filter replacement:5.8 L (6.13 US qt, 5.10 Imp qt)S6P23090Power unitCHK ADJPeriodic check and adjustment3-7 6P23H112. While turning the flywheel magnet clock-wise,checktheinterioraandtheexte-riorbofthetimingbelt.Replaceifcracked, damaged, or worn.NOTE:Toreplacethetimingbelt,seeChapter5,Replacing the timing belt.Checking the spark plug1. Remove the ECM cover.2. Removetheignitioncoils,andthenremove the spark plugs.3. Clean the electrodes 1 with a spark plugcleaner or wire brush. Replace the sparkplug if necessary.4. Checktheelectrodesforerosionandexcessivecarbonorotherdeposits,andthegasketfordamage.Replacethespark plug if necessary.5. Check the spark plug gap a. Adjust if outof specification.6. Install the spark plugs, tighten them tem-porary, then to the specified torque usinga spark plug wrench.7. Install the ignition coils.8. Install the ECM cover.Checking the thermostat1. Reduce the fuel pressure.S6P23100abSpecified spark plug:LFR6A-11 (NGK)Spark plug gap a:1.01.1 mm (0.0390.043 in)T R..Spark plug:25 Nm (2.5 kgfm, 18.4 ftlb)T R..Ignition coil bolt:7 Nm (0.7 kgfm, 5.2 ftlb)6P23H11 3-8123456789NOTE:Toreducethefuelpressure,seeChapter4,Reducing the fuel pressure.2. Remove the flywheel magnet cover.3. Disconnect the oil control valve couplers1.4. Disconnect the thermoswitch connectors2.5. Disconnect the quick connectors 3. WARNINGItisdangerousifthequickconnectorisremovedsuddenlysincepressurizedfuelwillsprayout.Besuretoreducethefuelpressurebeforeremovingthequickcon-nector.NOTE:Todisconnectthequickconnector,seeChapter 4, Disconnecting the quick connec-tor.6. Removethecovers4andthermostats5 (port and starboard).CAUTION:Donotreusethegaskets6,alwaysreplace them with new ones.7. Suspend the thermostat in a container ofwater.8. Placeathermometerinthewaterandslowly heat the water.1S6P2312023PORT1S6P2313032 STBD5S6P23320E46S69J5E40Power unitCHK ADJPeriodic check and adjustment3-9 6P23H119. Checkthethermostatvalveopeningatthespecifiedwatertemperatures.Replace if out of specification.10. Install the thermostats and covers.NOTE:Itisrecommendedtocheckthethermostatcover anodes before installing the thermostatcovers.11. Connectthethermoswitchconnectors,quickconnectors,andoilcontrolvalvecouplers.12. Route and fasten the wiring harness in itsoriginal position.13. Install the flywheel magnet cover.Checking the cooling water passage1. Checkthecoolingwaterinletcovers1and cooling water inlet. Clean if clogged.2. Placethelowerunitinwater,andthenstart the engine.3. Check for water flow at the cooling waterpilot hole. If there is no water flow, checkthe cooling water passage inside the out-board motor.Control system 3Checking the engine idle speed1. Start the engine and warm it up for 5 min-utes.2. ChecktheengineidlespeedusingtheYamahagenuinetachometer(on-boardmeter) or using the YDIS.NOTE:To connect and operate the YDIS, see Chap-ter 9, YDIS and the YDIS (version 1.23a orlater) Instruction Manual.Water temperatureValve lift a 5862 C (136144 F)0.05 mm (0.0020 in) (valve begins to lift)above 70 C (158 F)more than 4.3 mm (0.17 in)S6P2315011S6P210506P23H11 3-10123456789Adjusting the throttle cable1. Settheremotecontrollevertotheneu-tralpositionandfullyclosethethrottlelever.2. Loosenthelocknut1,removetheclip2, and then disconnect the throttle cablejoint 3.3. Checkthattheacceleratorlever4con-tacts the fully closed stopper 5.4. Adjustthepositionofthethrottlecablejointuntilitsholeisalignedwiththesetpin on the lever. WARNINGThethrottlecablejointmustbescrewedin a minimum of 8.0 mm (0.31 in) a.NOTE:Pullthethrottlecabletowardstheenginetoremoveanyfreeplayinthecablebeforeadjustingthepositionofthethrottlecablejoint.5. Connect the throttle cable joint 3, installtheclip2,andthentightenthelocknut1.Engine idle speed: 600700 r/min1S6P2333023S6P2334054S6D53190aS6P23350231Power unit / Control systemCHK ADJPeriodic check and adjustment3-11 6P23H116. Operate the remote control lever severaltimes,andthencheckthatthemarkbonthelever4haspassedthemarkcon the stopper 5 when the remote con-trolleverisinthefullyopenpositionofthe throttle.7. Check that the lever 4 contacts the fullyclosed stopper 5 when the remote con-trol lever is in the fully closed position.8. Check the throttle cable for smooth oper-ation and, if necessary, repeat steps 27.Checking the gear shift operation1. Checkthatthegearshiftoperatessmoothly when shifting it from the neutralposition to forward or reverse. Adjust theshift cable length if necessary.2. Checktheneutralswitchforcontinuity.Adjust the shift cable length or check theneutral switch if necessary.NOTE:Tochecktheneutralswitch,seeChapter8,Checking the neutral switch.3. Set the gear shift to the neutral position.4. Loosenthelocknut1,removetheclip2,andthendisconnecttheshiftcablejoint 3.5. Align the alignment mark a on the bush-ingandalignmentmarkbonthebracket.6. Adjust the position of the shift cable jointuntil its hole is aligned with the set pin. WARNINGThe shift cable joint must be screwed in aminimum of 8.0 mm (0.31 in) c.7. Connectthecablejoint,installtheclip,and then tighten the locknut.Gear shift positionLead colorBlue/green (L/G)Black (B)Forward or reverseNeutralS6P23360b54cS69J33706P23H11 3-121234567898. Check the gear shift for smooth operation,checktheoperationoftheneutralswitchand, if necessary, repeat steps 37.Bracket unit 3Checking the PTT operation1. Fully tilt the outboard motor up and downa few times and check the entire trim andtilt range for smooth operation. Check thePTT fluid level if necessary.NOTE:Be sure to listen to the winding sound of thePTT motor for smooth operation.2. Fully tilt the outboard motor up, and thensupportitwiththetiltstoplever1tocheck the lock mechanism of the lever.Checking the PTT fluid level1. Fully tilt the outboard motor up, and thensupport it with the tilt stop lever 1. WARNINGAftertiltinguptheoutboardmotor,besure to support it with the tilt stop lever.Otherwise, the outboard motor could sud-denlylowerifthePTTunitshouldlosefluid pressure.2. Removethereservoircap2,andthencheck the fluid level in the reservoir. WARNINGMakesurethatthetrimandtiltramsarefullyextendedwhenremovingthereser-voircap,otherwisefluidcanspurtoutfrom the unit due to internal pressure.NOTE:Ifthefluidisatthecorrectlevel,asmallamountoffluidshouldoverflowoutofthefiller hole when the cap is removed.S6P23190Control system / Bracket unitCHK ADJPeriodic check and adjustment3-13 6P23H113. Ifnecessary,addsufficientfluidoftherecommendedtypeuntilitoverflowsoutof the filler hole.4. Install the new O-ring and reservoir cap,and then tighten the cap to the specifiedtorque.Lower unit 3Checking the gear oil level1. Fully tilt the outboard motor down.2. Removethecheckscrew1,andthencheck the gear oil level in the lower case.NOTE:Iftheoilisatthecorrectlevel,asmallamountofoilshouldoverflowoutofthecheckholewhenthecheckscrewisremoved.3. If necessary, add sufficient gear oil of therecommendedtypeuntilitoverflowsoutof the check hole.4. Installthenewgasketandcheckscrew,andthentightenthescrewtothespeci-fied torque.Changing the gear oil1. Tilt the outboard motor up slightly.2. Place a drain pan under the drain screw1,removethedrainscrew,thenthecheck screw 2 and let the oil drain com-pletely.3. Check the oil for metal and discoloration,andcheckitsviscosity.Checktheinter-nal parts of the lower case if necessary.4. Insertagearoiltubeorgearoilpumpinto the drain hole and slowly fill the gearoil until oil flows out of the check hole andno air bubbles are visible.Recommended PTT fluid:ATF Dexron II T R..Reservoir cap:7 Nm (0.7 kgfm, 5.2 ftlb)Recommended gear oil:Hypoid gear oilAPI: GL-4SAE: 90S60V33201T R..Gear oil check screw:9 Nm (0.9 kgfm, 6.6 ftlb)6P23H11 3-141234567895. Installthenewgaskets,checkscrew,andquicklyinstallthedrainscrew,andthen tighten them to the specified torque.Checking the lower unit for air leakage1. Removethecheckscrew1,andtheninstall the special service tool.2. Applythespecifiedpressuretocheckthatthepressureismaintainedinthelower unit for at least 10 seconds.CAUTION:Do not over pressurize the lower unit, oth-erwise the oil seals may be damaged.NOTE:Cover the check hole with a rag when remov-ing the tester from the lower unit.3. If the specified pressure cannot be main-tained,checkthedriveshaft,propellershaft and shift rod oil seals for damage. Ifnecessary,checktheeachshaftforbends and damage.Checking the propeller1. Checkthepropellerbladesandsplines.Replace if cracked, damaged, or worn.General 3Checking the anode1. Checktheanodesandtrimtab.Cleanifthere are scales, grease, or oil.Recommended gear oil:Hypoid gear oilAPI: GL-4SAE: 90Gear oil quantity:Regular rotation model:1,150 cm3 (38.9 US oz, 40.6 Imp oz)Counter rotation model:1,000 cm3 (33.8 US oz, 35.3 Imp oz)T R..Gear oil check screw and drain screw:9 Nm (0.9 kgfm, 6.6 ftlb)Leakage tester: 90890-06840Lower unit holding pressure:70 kPa (0.7 kgf/cm2, 10 psi)S6P23310EBracket unit / Lower unit / GeneralCHK ADJPeriodic check and adjustment3-15 6P23H11CAUTION:Do not oil, grease, or paint the anodes orthe trim tab, otherwise they will be ineffec-tive.NOTE:If it is necessary to disassemble the outboardmotor to check an anode, refer to the applica-ble disassembly procedure in this manual.2. Replace the anodes or trim tab if exces-sivelyeroded.Inaddition,checktheground lead.Checking the battery1. Check the battery electrolyte level. If thelevelisatorbelowtheminimumlevelmark a, add distilled water until the levelisbetweenthemaximumandminimumlevel marks.S6P23270ES6P23210 S6P234006P23H11 3-161234567892. Check the specific gravity of the electro-lyte.Fullychargethebatteryifbelowspecification. WARNINGBatteryelectrolyteisdangerous;itcon-tains sulfuric acid which is poisonous andhighly caustic.Always follow these preventive measures: Avoidbodilycontactwithelectrolyteasit can cause severe burns or permanenteye injury. Wear protective eye gear when handlingor working near batteries.Antidote (EXTERNAL): SKIN Wash with water. EYES Flush with water for 15 minutesand get immediate medical attention.Antidote (INTERNAL): Drinklargequantitiesofwaterormilkfollowedwithmilkofmagnesia,beatenegg,orvegetableoil.Getimmediatemedical attention.Batteriesgenerateexplosive,hydrogengas. Always follow these preventive mea-sures: Chargebatteriesinawell-ventilatedarea. Keep batteries away from fire, sparks oropenflames(e.g.,weldingequipment,lighted cigarettes). DO NOT SMOKE when charging or han-dling batteries.KEEPBATTERIESANDELECTROLYTEOUT OF REACH OF CHILDREN.NOTE: Batteriesvarypermanufacturer.Thepro-cedures mentioned in this manual may notalways apply, therefore, consult the instruc-tion manual of the battery. Disconnect the negative battery cable first,then the positive battery cable.Lubricating the outboard motor1. Apply water resistant grease to the areasshown.S69J3620Electrolyte specific gravity:1.280 at 20 C (68 F)S6P23240AGeneralCHK ADJPeriodic check and adjustment3-17 6P23H11NOTE:Applygreasetothegreasenippleuntilitflows from the bushings a.2. Applylowtemperatureresistantgreaseto the area shown.3. Applycorrosionresistantgreasetothearea shown.S6D03010AAS6P23410C6P23H11FUEL123456789Fuel systemHose routing................................................................................................... 4-1Fuel hose and blowby hose....................................................................... 4-1Vapor gas hose ......................................................................................... 4-2Cooling water hose.................................................................................... 4-3Checking the throttle valve operation ........................................................ 4-5Checking the TPS...................................................................................... 4-5Measuring the fuel pressure...................................................................... 4-7Checking the pressure regulator ............................................................... 4-8Reducing the fuel pressure........................................................................ 4-9Disconnecting the quick connector............................................................ 4-9Draining the fuel ...................................................................................... 4-10Fuel filter....................................................................................................... 4-11Intake manifold............................................................................................. 4-12Installing the intake manifold ................................................................... 4-13Installing the intake silencer .................................................................... 4-13Throttle body ................................................................................................ 4-15Checking the canister .............................................................................. 4-18Checking the canister check valve .......................................................... 4-18Installing the throttle body........................................................................ 4-18Low-pressure fuel pump ............................................................................. 4-20Checking the check valve........................................................................ 4-21Vapor separator............................................................................................ 4-22Removing the fuel hose clamp ................................................................ 4-25Installing the fuel hose clamp .................................................................. 4-25Checking the vapor separator ................................................................. 4-25Fuel injector.................................................................................................. 4-26Installing the fuel injector ......................................................................... 4-27FUELFuel system4-1 6P23H11Hose routing 4Fuel hose and blowby hose1 Fuel hose (fuel joint-to-fuel filter)2 Fuel hose (fuel filter-to-joint)3 Fuel hose (joint-to-low-pressure fuel pump)4 Fuel hose (low-pressure fuel pump-to-filter)5 Fuel hose (filter-to-joint)6 Fuel hose (joint-to-check valve)7 Fuel hose (check valve-to-joint)8 Fuel hose (vapor separator-to-quick connector)9 Fuel hose (quick connector-to-joint)0 Fuel hose (joint-to-quick connector)A Fuel hose (pressure regulator-to-fuel cooler)B Fuel hose (fuel cooler-to-vapor separator)C Blowby hose (starboard cylinder head cover-to-intake silencer)S6P2401089A05463127B C6P23H11 4-2123456789Vapor gas hose1 Vapor gas hose (vapor separator-to-joint)2 Vapor gas hose (vapor separator-to-joint)3 Vapor gas hose (joint-to-joint)4 Vapor gas hose (joint-to-joint)5 Vapor gas hose (joint-to-canister tank port)6 Vapor gas hose (canister purge port-to-joint)7 Vapor gas hose (joint-to-vapor shut-off valve)8 Vapor gas hose (vapor shut-off valve-to-surgetank)9 Vaporgashose(intakesilencer-to-checkvalve)0 Vapor gas hose (check valve-to-joint)A Vapor gas hose (canister atmospheric port-to-joint)B Vapor gas hose (joint-to-joint)C Vapor gas hose (joint-to-check valve)D Vaporgashose(checkvalve-to-topcowlinglock)E Vacuum hose (pressure regulator-to-joint)F Vacuumhose(intakeairpressuresensor-to-joint)G Vacuum hose (joint-to-surge tank)S6P24020EBEDC3214A5678GF09STBDD9788EFG2E1A65Hose routingFUELFuel system4-3 6P23H11Cooling water hose1 Cooling water hose (cylinder block-to-fuel cooler)2 Cooling water hose (fuel cooler-to-Rectifier Regulator)3 Cooling water hose (Rectifier Regulator-to-cooling water pilot hole)4 Cooling water hose (port thermostat cover-to-cylinder block)5 Cooling water hose (starboard thermostat cover-to-cylinder block)6 Cooling water hose (starboard cylinder head-to-cooling water pressure sensor adapter)7 Flushing hose (joint-to-cooling water passage cover)a Fuel coolerb Rectifier Regulatorc Cooling water pilot hole (on the bottom cowling)d Cooling water pressure sensor adaptere Cooling water passage cover (on the cylinder block)1422356176S6P24450EPORT STBDacbed6P23H11 4-41234567891 Cooling water hose (cylinder block-to-fuel cooler)2 Cooling water hose (Rectifier Regulator-to-cooling water pilot hole)3 Flushing hose (joint-to-cooling water passage cover)4 Flushing hose (flushing hose adapter-to-joint)5 Speedometer hose5134S6P244902Hose routingFUELFuel system4-5 6P23H11Checking the throttle valve operation1. Removetheflywheelmagnetcoverandintake silencer.NOTE:See the exploded diagram (4-12).2. Pushthethrottlevalve,andcheckthatthevalvemovessmoothlywhentheengine start switch is turned to OFF.3. Turn the engine start switch to ON.4. Checkthatthethrottlevalvesoperatesmoothlywhentheremotecontrolleveris shifted from the fully closed position tothe fully open position.5. Installtheintakesilencerandflywheelmagnet cover.NOTE: To install the intake silencer, see Installingthe intake silencer. Tochecktheacceleratorpositionsensor,seeChapter8,CheckingtheacceleratorpositionsensorcircuitandCheckingtheacceler