YAMAHA OWNER'S MANUALS...Title 9.9 15 Owners Manual Author Yamaha Motor Corporation Subject 9.9 15...

9.915

OWNER’S MANUAL

LIT-18626-07-9063V-28199-1D

U.S.A.Edition Read this manual carefully before operating this outboard motor.

©2019 Yamaha M

otor Corporation, U.S.A.

ZMU01690

Read this manual carefully before operating this outboard motor. Keep thismanual onboard in a waterproof bag when boating. This manual should staywith the outboard motor if it is sold.

U63V1DE0.book Page 1 Thursday, February 21, 2008 2:31 PM

©2019 Yamaha M


Important manual informationEMU31283

To the ownerThank you for choosing a Yamaha outboardmotor. This Owner’s Manual contains infor-mation needed for proper operation, mainte-nance and care. A thorough understanding ofthese simple instructions will help you obtainmaximum enjoyment from your new Yamaha.If you have any question about the operationor maintenance of your outboard motor,please consult a Yamaha dealer.In this Owner’s Manual particularly importantinformation is distinguished in the followingways.

: This is the safety alert symbol. It is usedto alert you to potential personal injury haz-ards. Obey all safety messages that followthis symbol to avoid possible injury or death.

WARNINGEWM00781

A WARNING indicates a hazardous situa-tion which, if not avoided, could result indeath or serious injury.

NOTICEECM00701

A NOTICE indicates special precautionsthat must be taken to avoid damage to theoutboard motor or other property.

TIP:A TIP provides key information to make pro-cedures easier or clearer.

Yamaha continually seeks advancements inproduct design and quality. Therefore, whilethis manual contains the most current productinformation available at the time of printing,there may be minor discrepancies between

your machine and this manual. If there is anyquestion concerning this manual, please con-sult your Yamaha dealer.

TIP:The 9.9MH, 15MH and the standard accesso-ries are used as a base for the explanationsand illustrations in this manual. Thereforesome items may not apply to every model.EMU25111

9.9, 15OWNER’S MANUAL

©2008 by Yamaha Motor Corporation, USA

1st edition, February 2008All rights reserved.

Any reprinting or unauthorized usewithout the written permission ofYamaha Motor Corporation, USA

is expressly prohibited.Printed in Japan

P/N LIT-18626-07-90


©2019 Yamaha M


Table of contents

Safety information.............................1Outboard motor safety .................... 1

Propeller ............................................. 1Rotating parts ..................................... 1Hot parts............................................. 1Electric shock ..................................... 1Engine shut-off cord (lanyard) ............ 1Gasoline ............................................. 1Gasoline exposure and spills ............. 1Carbon monoxide ............................... 1Modifications ...................................... 2

Boating safety ................................. 2Alcohol and drugs............................... 2Personal flotation devices .................. 2People in the water............................. 2Passengers ........................................ 2Overloading ........................................ 2Avoid collisions................................... 2Weather.............................................. 3Accident reporting .............................. 3Boat education and training................ 3Passenger training ............................. 3Boating safety publications................. 3Laws and regulations ......................... 3

Boating organizations...................... 4Basic boating rules

(Rules of the road) ....................... 4Steering and sailing rules and sound

signals............................................. 4Rules when encountering vessels...... 5Other special situations ...................... 6

General information ..........................8Identification numbers record.......... 8

Outboard motor serial number ........... 8Read manuals and labels................ 9

Warning labels.................................... 9Specifications and requirements... 12

Specifications ................................ 12Installation requirements ............... 13

Boat horsepower rating .................... 13Mounting motor ................................ 13

Propeller selection ........................ 13Start-in-gear protection ................. 13Engine oil requirements ................ 14Fuel requirements ......................... 14

Gasoline ........................................... 14Ring Free Fuel Additive.................... 14

Muddy or acidic water ................... 15Anti-fouling paint ........................... 15Motor disposal requirements......... 15Emergency equipment .................. 15Emission control information......... 15

North American models .................... 15Components .................................... 17

Components diagram.................... 17Fuel tank........................................... 17Fuel joint ........................................... 18Fuel gauge ....................................... 18Fuel tank cap.................................... 18Air vent screw................................... 18Tiller handle...................................... 18Gear shift lever ................................. 18Throttle grip ...................................... 18Throttle indicator............................... 19Throttle friction adjuster .................... 19Engine shut-off cord (lanyard) and

clip................................................. 19Engine stop button ........................... 20Choke knob ...................................... 20Manual starter handle....................... 20Steering friction adjuster................... 20Trim rod (tilt pin) ............................... 21Tilt lock mechanism.......................... 21Tilt support bar ................................. 21Top cowling lock lever(s)

(turn type)...................................... 22Carrying handle ................................ 22

Installation ....................................... 23Installation..................................... 23

Mounting the outboard motor ........... 23Clamping the outboard motor ........... 24

Operation ......................................... 26First-time operation ....................... 26

Breaking in engine............................ 26


©2019 Yamaha M


Table of contents

Getting to know your boat ................ 26Checks before starting engine ...... 26

Fuel level .......................................... 26Remove cowling ............................... 27Fuel system...................................... 27Controls ............................................ 27Engine shut-off cord (lanyard) .......... 27Oil ..................................................... 28Engine .............................................. 28Install cowling ................................... 28

Filling fuel and engine oil............... 28Filling fuel for portable tank .............. 28Gasoline and oil mixing (100:1)........ 29

Operating engine........................... 30Feeding fuel (portable tank) ............. 30Starting engine ................................. 31

Checks after starting engine ......... 33Cooling water ................................... 33

Warming up engine ....................... 33Choke start models .......................... 33

Checks after engine warm-up ....... 33Shifting ............................................. 33Stop switches ................................... 33

Shifting .......................................... 34Stopping boat ................................ 35Stopping engine ............................ 35

Procedure......................................... 35Trimming outboard motor.............. 35

Adjusting trim angle for manual tilt models .......................................... 36

Adjusting boat trim............................ 36Tilting up and down ....................... 37

Procedure for tilting up (manual tilt models)....................... 38

Procedure for tilting down (manual tilt models)....................... 38

Shallow water................................ 39Cruising in shallow water

(manual tilt models)....................... 39

Cruising in other conditions........... 40Maintenance .................................... 41

Transporting and storing outboard motor.......................................... 41Clamp screw mounting models ........ 41Storing outboard motor..................... 41Procedure......................................... 42Lubrication........................................ 43Cleaning and anticorrosion

measures ...................................... 43Cleaning the outboard motor ............ 43Checking painted surface of motor... 43

Periodic maintenance ................... 43Replacement parts ........................... 44Maintenance interval guidelines ....... 44Maintenance chart 1......................... 45Maintenance chart 2......................... 46Greasing........................................... 47Cleaning and adjusting spark plug ... 48Checking fuel filter ............................ 48Inspecting idling speed..................... 48Checking wiring and connectors ...... 49Checking propeller ........................... 49Removing propeller .......................... 50Installing propeller ............................ 50Changing gear oil ............................. 51Cleaning fuel tank............................. 52Inspecting and replacing anode(s) ... 53

Trouble Recovery............................ 54Troubleshooting ............................ 54Temporary action in emergency ... 57

Impact damage................................. 57Starter will not operate ..................... 57Emergency starting engine............... 58


©2019 Yamaha M


Table of contents

Treatment of submerged motor..... 59Consumer information.................... 60

Important warranty information for U.S.A. and Canada .................... 60

YAMAHA MOTOR CORPORATION, U.S.A.OUTBOARD MOTOR TWO YEAR LIMITED WARRANTY..... 62

IMPORTANT WARRANTY INFORMATION IF YOU USE YOUR YAMAHA OUTSIDE THE USA OR CANADA ............. 65


©2019 Yamaha M


1

Safety informationEMU33622

Outboard motor safetyObserve these precautions at all times.EMU36500

PropellerPeople can be injured or killed if they come incontact with the propeller. The propeller cankeep moving even when the motor is in neu-tral, and sharp edges of the propeller can cuteven when stationary.� Shut off the engine when a person is in the

water near you.� Keep people out of reach of the propeller,

even when the engine is off.EMU33630

Rotating partsHands, feet, hair, jewelry, clothing, PFDstraps, etc. can become entangled with inter-nal rotating parts of the engine, resulting in se-rious injury or death.Keep the top cowling in place whenever pos-sible. Do not remove or replace the cowlingwith the engine running.Only operate the engine with the cowling re-moved according to the specific instructions inthe manual. Keep hands, feet, hair, jewelry,clothing, PFD straps, etc. away from any ex-posed moving parts.EMU33640

Hot partsDuring and after operation, engine parts arehot enough to cause burns. Avoid touchingany parts under the top cowling until the en-gine has cooled.EMU33650

Electric shockDo not touch any electrical parts while startingor operating the engine. They can causeshock or electrocution.EMU33671

Engine shut-off cord (lanyard)Attach the engine shut-off cord so that the en-gine stops if the operator falls overboard orleaves the helm. This prevents the boat from

running away under power and leaving peo-ple stranded, or running over people or ob-jects.Always attach the engine shut-off cord to asecure place on your clothing or your arm orleg while operating. Do not remove it to leavethe helm while the boat is moving. Do not at-tach the cord to clothing that could tear loose,or route the cord where it could become en-tangled, preventing it from functioning.Do not route the cord where it is likely to beaccidentally pulled out. If the cord is pulledduring operation, the engine will shut off andyou will lose most steering control. The boatcould slow rapidly, throwing people and ob-jects forward.EMU33810

GasolineGasoline and its vapors are highly flam-mable and explosive. Always, refuel accord-ing to the procedure on page 30 to reduce therisk of fire and explosion.EMU33820

Gasoline exposure and spillsTake care not to spill gasoline. If gasolinespills, wipe it up immediately with dry rags.Dispose of rags properly.If any gasoline spills onto your skin, immedi-ately wash with soap and water. Changeclothing if gasoline spills on it.If you swallow gasoline, inhale a lot of gaso-line vapor, or get gasoline in your eyes, getimmediate medical attention. Never siphonfuel by mouth.EMU33900

Carbon monoxideThis product emits exhaust gases which con-tain carbon monoxide, a colorless, odorlessgas which may cause brain damage or deathwhen inhaled. Symptoms include nausea,dizziness, and drowsiness. Keep cockpit andcabin areas well ventilated. Avoid blocking ex-haust outlets.


©2019 Yamaha M


Safety information

2

EMU33780

ModificationsDo not attempt to modify this outboard motor.Modifications to your outboard motor may re-duce safety and reliability, and render the out-board unsafe or illegal to use.EMU33740

Boating safetyThis section includes a few of the many im-portant safety precautions that you should fol-low when boating.EMU33710

Alcohol and drugsNever operate after drinking alcohol or takingdrugs. Intoxication is one of the most commonfactors contributing to boating fatalities.EMU33720

Personal flotation devicesHave an approved personal flotation device(PFD) on board for every occupant. Yamaharecommends that you must wear a PFDwhenever boating. At a minimum, childrenand non-swimmers should always wearPFDs, and everyone should wear PFDs whenthere are potentially hazardous boating condi-tions.EMU33730

People in the waterAlways watch carefully for people in the wa-ter, such as swimmers, skiers, or divers,whenever the engine is running. When some-one is in the water near the boat, shift intoneutral and shut off the motor.Stay away from swimming areas. Swimmerscan be hard to see.The propeller can keep moving even whenthe motor is in neutral. Shut off the enginewhen a person is in the water near you.EMU33750

PassengersConsult your boat manufacturer’s instructionsfor details about appropriate passenger loca-tions in your boat and be sure all passengersare positioned properly before accelerating

and when operating above an idle speed.Standing or sitting in non-designated loca-tions may result in being thrown either over-board or within the boat due to waves, wakes,or sudden changes in speed or direction.Even when people are positioned properly,alert your passengers if you must make anyunusual maneuver. Always avoid jumpingwaves or wakes.EMU33760

OverloadingDo not overload the boat. Consult the boat ca-pacity plate or boat manufacturer for maxi-mum weight and number of passengers. Besure that weight is properly distributed ac-cording to the boat manufacturers instruc-tions. Overloading or incorrect weightdistribution can compromise the boats han-dling and lead to an accident, capsizing orswamping.EMU33771

Avoid collisionsScan constantly for people, objects, and oth-er boats. Be alert for conditions that limit yourvisibility or block your vision of others.

Operate defensively at safe speeds andkeep a safe distance away from people, ob-jects, and other boats.� Do not follow directly behind other boats or

waterskiers.

ZMU06025


©2019 Yamaha M


Safety information

3

� Avoid sharp turns or other maneuvers thatmake it hard for others to avoid you or un-derstand where you are going.

� Avoid areas with submerged objects orshallow water.

� Ride within your limits and avoid aggressivemaneuvers to reduce the risk of loss of con-trol, ejection, and collision.

� Take early action to avoid collisions. Re-member, boats do not have brakes, andstopping the engine or reducing throttle canreduce the ability to steer. If you are notsure that you can stop in time before hittingan obstacle, apply throttle and turn in anoth-er direction.

EMU33790

WeatherStay informed about the weather. Checkweather forecasts before boating. Avoid boat-ing in hazardous weather.EMU33800

Accident reportingBoat operators are required by law to file aBoating Accident Report with their state boat-ing law enforcement agency if their boat is in-volved in any of the following accidents:1. There is loss of life or probable loss of life.2. There is personal injury that requires

medical attention beyond first aid.3. There is property damage to boats or oth-

er property over a certain amount.4. There is complete loss of a boat.Contact local law enforcement personnel if areport is necessary.EMU33870

Boat education and trainingOperators should take a boating safetycourse. This may be required in your state.Many of the organizations listed in the nextsection can provide information about cours-es in your area.

You may also want to consider an Internet-based program for basic boater education.The Online Boating Safety Course providedby the BoatU.S. Foundation, is approved bythe National Association of State Boating LawAdministrators (NASBLA) and recognized bythe United States Coast Guard. Most, but notall, states accept this course to meet theirminimum requirements. While it cannot re-place an in-depth course such as one offeredby the U.S. Coast Guard, U.S. Power Squad-ron, or other organization, this online coursedoes provide a general overview of the basicsin boating safety, requirements, navigation,and operation. Upon successful completion ofthe course, the user can download a certifi-cate of completion immediately or, for a smallcharge, request one by mail. To take this freecourse, go to boatus.org.EMU33880

Passenger trainingMake sure at least one other passenger istrained to operate the boat in the event of anemergency.EMU33890

Boating safety publicationsBe informed about boating safety. Additionalpublications and information can be obtainedfrom many boating organizations.EMU33590

Laws and regulationsKnow the marine laws and regulations whereyou will be boating- and obey them. Severalsets of rules prevail according to geographiclocation, but all are basically the same as theInternational Rules of the Road. The rulespresented in the following section are con-densed- and have been provided for yourconvenience only.


©2019 Yamaha M


Safety information

4

Contact the U.S. Coast Guard, the NationalAssociation of State Boating Law Administra-tors, or your local Power Squadron for a com-plete set of rules governing the waters inwhich you will be using your boat.EMU33680

Boating organizationsThe following organizations provide boatingsafety training and information about boatingsafety and laws.

United States Coast GuardConsumer Affairs Staff (G-BC)Office of Boating, Public, and Consumer Af-fairsU.S. Coast Guard HeadquartersWashington, D.C. 20593-0001Boating Safety Hotline: 1-800-368-5647www.uscgboating.org

United States Power Squadrons1-888-FOR-USPS (1-888-367-8777)www.usps.org

Boat Owners Association of The UnitedStates1-800-336-BOAT (1-800-336-2628)www.boatus.com

National Association of State Boating LawAdministrators (NASBLA)1500 Leestown Road, Suite 330Lexington, KY 4051 859-225-9497859-225-9497www.nasbla.org

National Marine Manufacturers Associa-tion (NMMA)200 East Randolph DriveSuite 5100Chicago, IL 606001

www.nmma.org

Marine Retailers Association of America155 N. Michigan Ave. Chicago,IL 60601www.mraa.com

EMU33690

Basic boating rules (Rules of the road)

Just as there are rules that apply when youare driving on streets and highways, there arewaterway rules that apply when you are driv-ing your boat. These rules are used interna-tionally. (For USA: and are also enforced bythe United States Coast Guard and localagencies.) You should be aware of theserules, and follow them whenever you encoun-ter another vessel on the water.EMU33700

Steering and sailing rules and sound signalsWhenever two vessels on the water meet oneanother, one vessel has the right-of-way; it iscalled the “stand-on” vessel. The vessel thatdoes not have the right-of-way is called the“give-way” or “burdened”vessel. These rulesdetermine which vessel has the right-of-way,and what each vessel should do.

Stand-on vesselThe vessel with the right-of-way has the dutyto continue its course and speed, except toavoid an immediate collision. When you main-tain your direction and speed, the other vesselwill be able to determine how best to avoidyou.

Give-way vesselThe vessel that does not have the right-of-way has the duty to take positive and timelyaction to stay out of the way of the Stand-On


©2019 Yamaha M


Safety information

5

vessel. Normally, you should not cross in frontof the vessel with the right-of-way. You shouldslow down or change directions briefly andpass behind the other vessel. You should al-ways move in such a way that the operator ofthe other vessel can see what you are doing.“ The general prudential rule ”This rule is called Rule 2 in the InternationalRules and says,“ In obeying and construing these rules dueregard shall be had to all dangers of naviga-tion and collision, and to any special circum-stances, which may render a departure fromthe above rules necessary in order to avoidimmediate danger.”In other words, follow the standard rules ex-cept when a collision will occur unless bothvessels try to avoid each other. If that is thecase, both vessels become “ Give-Way ” ves-sels.EMU25521

Rules when encountering vesselsThere are three main situations that you mayencounter with other vessels which could leadto a collision unless the Steering Rules are fol-lowed:Meeting: (you are approaching another ves-sel head-on)Crossing: (you are traveling across the othervessel’s path)Overtaking: (you are passing or beingpassed by another vessel)In the following illustration, your boat is in thecenter. You should give the right-of-way toany vessels shown in white area (you are theGive-Way vessel). Any vessels in the shadedarea must yield to you (they are the Give-Wayvessels). Both you and the meeting vesselmust alter course to avoid each other.

MeetingIf you are meeting another power vessel headon, and are close enough to run the risk of col-lision, neither of you has the right-of-way Bothof you should alter course to avoid an acci-dent. You should keep the other vessel onyour port (left) side. This rule doesn’t apply ifboth of you will clear one another if you con-tinue on your set course and speed.

CrossingWhen two power driven vessels are crossingeach other’s path close enough to run the riskof collision, the vessel which has the other onthe starboard (right) side must keep out of theway of the other. If the other vessel is on yourright, you must keep out of its way; you are theGive-Way vessel. If the other vessel is onyour port (left) side, remember that youshould maintain course and direction, provid-ed the other vessel gives you the right-of-wayas it should.


©2019 Yamaha M


Safety information

6

OvertakingIf you are passing another vessel, you are the“Give-Way” vessel. This means that the othervessel is expected to maintain its course andspeed. You must stay out of its way until youare clear of it. Likewise, if another vessel ispassing you, you should maintain your speedand direction so that the other vessel cansteer itself around you.EMU25531

Other special situationsThere are three other rules you should beaware of when driving your boat around othervessels.Narrow channels and bendsWhen navigating in narrow channels, youshould keep to the right when it is safe andpractical to do so. If the operator of a power-driven vessel is preparing to go around abend that may obstruct the view of other watervessels, the operator should sound a pro-longed blast on the whistle (4 to 6 seconds). Ifanother vessel is around the bend, it tooshould sound the whistle. Even if no reply isheard, however, the vessel should still pro-ceed around the bend with caution. If you nav-igate such waters with your boat, you willneed to carry a portable air horn, availablefrom local marine supply stores.

Fishing vessel right-of-wayAll vessels that are fishing with nets, lines ortrawls are considered to be “fishing vessels”under the International Rules. Vessels withtrolling lines are not considered fishing ves-sels. Fishing vessels have the right-of-way re-gardless of position. Fishing vessels cannot,however, impede the passage of other ves-sels in narrow channels.Sailing vessel right-of-waySailing vessels should normally be given theright-of-way. The exceptions to this are:1. When the sailing vessel is overtaking the

power-driven vessel, the power-drivenvessel has the right-of-way.

2. Sailing vessels should keep clear of anyfishing vessel.

3. In a narrow channel, a sailing vesselshould not hamper the safe passage of apower-driven vessel that can navigateonly in such a channel.

Reading buoys and other markersThe waters of the United States are markedfor safe navigation by the lateral system ofbuoyage. Simply put, buoys and markershave an arrangement of shapes, colors, num-bers and lights to show which side of the buoya boater should pass on when navigating in aparticular direction. The markings on thesebuoys are oriented from the perspective of be-ing entered from seaward (the boater is goingtowards the port). This means that red buoysare passed on the starboard (right) side whenproceeding from open water into port, andblack buoys are to port (left) side. When navi-gating out of port, your position with respect tothe buoys should be reversed; red buoysshould be to port and black buoys to star-board.


©2019 Yamaha M


Safety information

7

Many bodies of water used by boaters are en-tirely within the boundaries of a particularstate. The Uniform State Waterway MarkingSystem has been devised for these waters.This system uses buoys and signs with dis-tinctive shapes and colors to show regulatoryor advisory information. These markers are

white with black letters and orange boarders.They signify speed zones, restricted areas,danger areas, and general information.Remember, markings may vary by geograph-ic location. Always consult local boating au-thorities before driving your boat in unfamiliarwaters.

ZMU01708


©2019 Yamaha M


General information

8

EMU25171

Identification numbers recordEMU25183

Outboard motor serial numberThe outboard motor serial number is stampedon the label attached to the port side of theclamp bracket.Record your outboard motor serial number inthe spaces provided to assist you in orderingspare parts from your Yamaha dealer or forreference in case your outboard motor is sto-len.

1. Outboard motor serial number location


©2019 Yamaha M


General information

9

EMU33520

Read manuals and labelsBefore operating or working on this motor:� Read this manual.� Read any manuals supplied with the boat.� Read all labels on the outboard motor and the boat.If you need any additional information, contact your Yamaha dealer.EMU33831

Warning labelsIf these labels are damaged or missing, contact your Yamaha dealer for replacements.9.9, 15

ZMU06037

1

2

3


©2019 Yamaha M


General information

10

1 2

3

ZMU05697


©2019 Yamaha M


General information

11

EMU33843

SymbolsThe following symbols mean as follows.

Notice/Warning

Read Owner’s Manual

Hazard caused by continuous rotation

Electrical hazard

Remote control lever/gear shift lever operat-ing direction, dual direction

Engine start/ Engine cranking

ZMU05696

ZMU05664

ZMU05665

ZMU05666

ZMU05667

ZMU05668


©2019 Yamaha M


Specifications and requirements

12

EMU31480

SpecificationsTIP:“(AL)” stated in the specification data belowrepresents the numerical value for the alumi-num propeller installed.Likewise, “(SUS)” represents the value forstainless steel propeller installed and “(PL)”for plastic propeller installed.EMU2821C

Dimension:Overall length:

873 mm (34.4 in)Overall width:

332 mm (13.1 in)Overall height S:

1040 mm (40.9 in)Transom height S:

440 mm (17.3 in)Weight (AL) S:

36.0 kg (79 lb)Performance:

Full throttle operating range:4500–5500 r/min

Maximum output:15MH 11.0 kW@5000 r/min (15 HP@5000 r/min)9.9MH 7.3 kW@5000 r/min (9.9 HP@5000 r/min)

Idling speed (in neutral):750 ±50 r/min

Engine:Type:

2-stroke LDisplacement:

246.0 cm³Bore × stroke:

56.0 × 50.0 mm (2.20 × 1.97 in)Ignition system:

CDI

Spark plug (NGK):B7HS-10

Spark plug gap:0.9–1.0 mm (0.035–0.039 in)

Control system:Tiller

Starting system:Manual

Starting carburetion system:Choke valve

Alternator output:80 W

Drive unit:Gear positions:

Forward-neutral-reverseGear ratio:

2.08 (27/13)Trim and tilt system:

Manual tiltPropeller mark:

JFuel and oil:

Recommended fuel:Regular unleaded gasoline

Min. pump octane:86

Fuel tank capacity:24.0 L (6.34 US gal, 5.28 Imp.gal)

Recommended engine oil:YAMALUBE 2-stroke outboard motor oil

Fuel:oil ratio:Regular gasoline:

100 :1Lubrication:

Pre-mixed fuel and oilRecommended gear oil:

Hypoid gear oil SAE#90Gear oil quantity:

0.250 L (0.264 US qt, 0.220 Imp.qt)


©2019 Yamaha M



13

Tightening torque for engine:Spark plug:

25.0 Nm (2.55 kgf-m, 18.4 ft-lb)Propeller nut:

17.0 Nm (1.73 kgf-m, 12.5 ft-lb)EMU33553

Installation requirementsEMU33563

Boat horsepower rating

WARNINGEWM01560

Overpowering a boat can cause severe in-stability.

Before installing the outboard motor(s), con-firm that the total horsepower of your motor(s)does not exceed the boats maximum horse-power rating. See the boat’s capacity plate orcontact the manufacturer.EMU33571

Mounting motor

WARNINGEWM01570

� Improper mounting of the outboard mo-tor could result in hazardous conditionssuch as poor handling, loss of control,or fire hazards.

� Because the motor is very heavy, spe-cial equipment and training is requiredto mount it safely.

Your dealer or other person experienced inproper rigging should mount the motor usingcorrect equipment and complete rigging in-structions. For further information, see page23.EMU34191

Propeller selectionNext to selecting an outboard, choosing theright propeller is one of the most importantpurchasing decisions a boater can make. Thetype, size, and design of your propeller havea direct impact on acceleration, top speed,fuel economy, and even engine life. Yamaha

designs and manufactures propellers for ev-ery Yamaha outboard motor and every appli-cation.Your outboard motor came with a Yamahapropeller chosen to perform well over a rangeof applications, but there may be uses wherea different propeller would be more appropri-ate.Your Yamaha dealer can help you select theright propeller for your boating needs. Selecta propeller that will allow the engine to reachthe middle or upper half of the operatingrange at full throttle with the maximum boat-load. Generally, chose a larger pitch propellerfor a smaller operating load and a smallerpitch propeller for a heavier load. If you carryloads that vary widely, chose the propellerthat lets the engine run in the proper range foryour maximum load but remember that youmay need to reduce your throttle setting tostay within the recommended engine speedrange when carrying lighter loads.For instructions on propeller removal and in-stallation, see page 49.

EMU25770

Start-in-gear protectionYamaha outboard motors or Yamaha-ap-proved remote control units are equipped withstart-in-gear protection device(s). This feature

1. Propeller diameter in inches2. Propeller pitch in inches3. Type of propeller (propeller mark)

ZMU04606

-x1 2 3


©2019 Yamaha M



14

permits the engine to be started only when itis in neutral. Always select neutral beforestarting the engine.EMU25651

Engine oil requirements

If the recommended engine oil is not avail-able, another 2-stroke engine oil with anNMMA-certified TC-W3 rating may be used.EMU36360

Fuel requirementsEMU36780

GasolineUse a good quality gasoline that meets theminimum octane rating. If knocking or pingingoccurs, use a different brand of gasoline orpremium unleaded fuel. Yamaha recomendsthat you use alcohol-free (see Gasohol) gas-oline whenever possible.

NOTICEECM01980

� Do not use leaded gasoline. Leaded gas-oline can seriously damage the engine.

� Avoid getting water and contaminants inthe fuel tank. Contaminated fuel cancause poor performance or engine dam-age. Use only fresh gasoline that hasbeen stored in clean containers.

GasoholThere are two types of gasohol: gasohol con-taining ethanol (E10) and that containingmethanol. Ethanol can be used if the ethanolcontent does not exceed 10% and the fuelmeets the minimum octane ratings. E85 is a

fuel containing 85% ethanol and must not beused in your outboard motor. All ethanolblends containing more than 10% ethanol cancause fuel system damage or cause enginestarting and running problems. Yamaha doesnot recommend gasohol containing methanolbecause it can cause fuel system damage orengine performance problems.It is recommended that you install a water-separating marine fuel filter assembly (10 mi-cron minimum) between your boat’s fuel tankand outboard motor when using ethanol. Eth-anol is known to allow moisture to be ab-sorbed into boat fuel tanks and systems.Moisture in the fuel can cause corrosion ofmetallic fuel system components, starting andrunning complaints and require additional fuelsystem maintenance.EMU27270

Ring Free Fuel AdditiveGasoline is a precise blend of many differentsubstances, each chosen to give certain char-acteristics. Gasoline blends have beenchanging in recent years in response to con-cerns about pollution and resulting emissionsregulations. One of the most obvious changeshas been the elimination of lead from most fu-els.As gasoline has changed, the amount of addi-tives such as aromatics and oxygenates hasincreased. These additives are important forthe engines in passenger cars, but they canhave detrimental effects in marine engines,because of increased deposits in the combus-tion chamber. When enough deposits collect,piston rings begin sticking. Performancedrops and engine wear increases dramatical-ly.While many additives available may reducedeposits, Yamaha recommends the use ofRing Free Fuel Additive, available from yourYamaha dealer. Ring Free Fuel Additive

Recommended engine oil:YAMALUBE 2-stroke outboard motor oil

Recommended gasoline:Regular unleaded gasoline with a mini-mum Octane rating of 86 (Pump Oc-tane Number) = (R+M)/2


©2019 Yamaha M



15

has repeatedly proven its ability to clean com-bustion deposits from inside the engine, nota-bly the critical piston-ring-land area, and fuelsystem components. Follow product labelingfor use instructions.EMU36880

Muddy or acidic waterYamaha strongly recommends that you haveyour dealer install the optional chromium-plat-ed water pump kit if you use the outboard mo-tor in muddy or acidic water conditions.However, depending on the model it might notbe required.EMU36330

Anti-fouling paintA clean hull improves boat performance. Theboat bottom should be kept as clean of marinegrowth as possible. If necessary, the boat bot-tom can be coated with an anti-fouling paintapproved for your area to inhibit marinegrowth.Do not use anti-fouling paint which includescopper or graphite. These paints can causemore rapid engine corrosion.

EMU36340

Motor disposal requirementsNever illegally discard (dump) the motorYamaha recommends consulting the dealerabout discarding the motor.EMU36351

Emergency equipmentKeep the following items onboard in casethere is trouble with the motor.

� A tool kit with assorted screwdrivers, pliers,wrenches (including metric sizes), andelectrical tape.

� Waterproof flashlight with extra batteries.� An extra engine shut-off cord (lanyard) with

clip.� Spare parts, such as an extra set of spark

plugs.Consult your Yamaha dealer for details.EMU25221

Emission control informationEMU25230

North American modelsThis engine conforms to U.S. EnvironmentalProtection Agency (EPA) regulations for ma-rine SI engines. See the label affixed to yourengine for details.EMU30390

Approval label of emission control certifi-cateThis label is attached to the bottom cowling.Existing Technology; N/A

1. Approval label location

ZMU06058

1


©2019 Yamaha M



16

EMU25262

Manufactured date labelThis label is attached to the clamp bracket orthe swivel bracket.

1. Manufactured date label location

Manufactured:

ZMU04346


©2019 Yamaha M


Components

17

EMU2579H

Components diagramTIP:* May not be exactly as shown; also may not be included as standard equipment on all models.9.9, 15

EMU25802

Fuel tankIf your model was equipped with a portablefuel tank, its function is as follows.

WARNINGEWM00020

The fuel tank supplied with this engine isits dedicated fuel reservoir and must notbe used as a fuel storage container. Com-mercial users should conform to relevantlicensing or approval authority regula-tions.

1. Top cowling2. Top cowling lock lever3. Cooling water pilot hole4. Tilt lock lever5. Manual starter handle6. Gear shift lever7. Engine stop button/Engine shut-off switch8. Tiller handle9. Throttle friction adjuster10.Clamp screw11.Carrying handle12.Choke knob13.Rope attachment14.Clamp bracket15.Trim rod16.Anti-cavitation plate

17.Cooling water inlet18.Propeller*19.Fuel hose


©2019 Yamaha M


Components

18

EMU25830

Fuel jointThis joint is used to connect the fuel line.EMU25841

Fuel gaugeThis gauge is located on either the fuel tankcap or on the fuel joint base. It shows the ap-proximate amount of fuel remaining in thetank.EMU25850

Fuel tank capThis cap seals the fuel tank. When removed,the tank can be filled with fuel. To remove thecap, turn it counterclockwise.EMU25860

Air vent screwThis screw is on the fuel tank cap. To loosenthe screw, turn it counterclockwise.EMU25911

Tiller handleTo change direction, move the tiller handle tothe left or right as necessary.

EMU25922

Gear shift leverPulling the gear shift lever towards you putsthe engine in forward gear so that the boatmoves ahead. Pushing the lever away fromyou puts the engine in reverse gear so that theboat moves astern.

EMU25941

Throttle gripThe throttle grip is on the tiller handle. Turnthe grip counterclockwise to increase speedand clockwise to decrease speed.

1. Fuel joint2. Fuel gauge3. Fuel tank cap4. Air vent screw

ZMU02284

3

1

4

2

1. Forward “ ”2. Neutral “ ”3. Reverse “ ”


©2019 Yamaha M


Components

19

EMU25961

Throttle indicatorThe fuel consumption curve on the throttle in-dicator shows the relative amount of fuel con-sumed for each throttle position. Choose thesetting that offers the best performance andfuel economy for the desired operation.

EMU25973

Throttle friction adjusterA friction device provides adjustable resis-tance to movement of the throttle grip or theremote control lever, and can be set accord-ing to operator preference.To increase resistance, turn the adjusterclockwise. WARNING! Do not overtightenthe friction adjuster. If there is too muchresistance, it could be difficult to move theremote control lever or throttle grip, whichcould result in an accident. [EWM00032]

To decrease resistance, turn the adjustercounterclockwise.

When constant speed is desired, tighten theadjuster to maintain the desired throttle set-ting.EMU25993

Engine shut-off cord (lanyard) and clipThe clip must be attached to the engine shut-off switch for the engine to run. The cordshould be attached to a secure place on theoperator’s clothing, or arm or leg. Should theoperator fall overboard or leave the helm, thecord will pull out the clip, stopping ignition tothe engine. This will prevent the boat fromrunning away under power. WARNING! At-tach the engine shut-off cord to a secureplace on your clothing, or your arm or legwhile operating. Do not attach the cord toclothing that could tear loose. Do not routethe cord where it could become entangled,preventing it from functioning. Avoid acci-dentally pulling the cord during normaloperation. Loss of engine power meansthe loss of most steering control. Also,without engine power, the boat could slowrapidly. This could cause people and ob-jects in the boat to be thrown forward.[EWM00122]

1. Throttle indicator


©2019 Yamaha M


Components

20

EMU26001

Engine stop buttonTo open the ignition circuit and stop the en-gine, push this button.

EMU26030

Choke knobTo supply the engine with the rich fuel mixturerequired to start, pull out this knob. The chokeknob has the 4 operating positions shown inthe following illustration.

EMU26070

Manual starter handleTo start the engine, first gently pull the handleout until resistance is felt. From that position,then pull the handle straight out quickly tocrank the engine.

EMU26122

Steering friction adjusterA friction device provides adjustable resis-tance to the steering mechanism, and can beset according to operator preference. An ad-justing screw or bolt is located on the swivelbracket.

1. Cord2. Clip3. Engine shut-off switch

1. Use to start a hot engine2. Use to warm up a cold engine or restart a

warm engine3. Use to warm up a cold engine or restart a

warm engine4. Use to start a cold engine


©2019 Yamaha M


Components

21

To increase resistance, turn the adjusterclockwise.To decrease resistance, turn the adjustercounterclockwise.

WARNINGEWM00040

Do not overtighten the friction adjuster. Ifthere is too much resistance, it could bedifficult to steer, which could result in anaccident.

EMU26261

Trim rod (tilt pin)The position of the trim rod determines theminimum trim angle of the outboard motor inrelation to the transom.

EMU30440

Tilt lock mechanismThe tilt lock mechanism is used to prevent theoutboard motor from lifting out of the waterwhen in reverse gear.

To tilt the outboard motor up, set the tilt locklever to the “ ” (up) position. To tilt the out-board motor down, set the tilt lock lever to the“ ” (down) position.EMU26332

Tilt support barThe tilt support bar keeps the outboard motorin the tilted up position.

NOTICEECM01660

Do not use the tilt support bar when traile-ring the boat. The outboard motor couldshake loose from the tilt support and fall.If the motor cannot be trailered in the nor-mal running position, use an additionalsupport device to secure it in the tilt posi-tion.

1. Tilt lock lever


©2019 Yamaha M


Components

22

EMU26372

Top cowling lock lever(s) (turn type)To remove the engine top cowling, turn thelock lever(s) and lift off the cowling. When in-stalling the cowling, check to be sure it fitsproperly in the rubber seal. Then lock thecowling again by returning the lever(s) to thelock position.

EMU26430

Carrying handleA carrying handle is included on the clampbracket. After setting the handle up, it enablesyou to carry the outboard motor easily withone hand.To set up the carrying handle, proceed as fol-lows:1. Place the tilt lock lever in the lock posi-

tion.2. Securely hook the arm on the carrying

handle end to the clamp bracket bar.

NOTICEECM00080

Place the tilt lock lever in the lock positionwhile using the carrying handle. Other-wise, the lower unit could fall to theground while carrying the motor.

1. Top cowling lock lever(s)

1. Carrying handle2. Clamp bracket bar


©2019 Yamaha M


Installation

23

EMU26902

InstallationThe information presented in this section is in-tended as reference only. It is not possible toprovide complete instructions for every possi-ble boat and motor combination. Propermounting depends in part on experience andthe specific boat and motor combination.

WARNINGEWM01590

� Overpowering a boat could cause se-vere instability. Do not install an out-board motor with more horsepower thanthe maximum rating on the capacityplate of the boat. If the boat does nothave a capacity plate, consult the boatmanufacturer.

� Improper mounting of the outboard mo-tor could result in hazardous conditionssuch as poor handling, loss of control,or fire hazards. For permanently mount-ed models, your dealer or other personexperienced in proper rigging shouldmount the motor.

EMU26911

Mounting the outboard motor

WARNINGEWM01720

Your dealer or other person experiencedin proper outboard motor mountingshould show you how to mount your out-board motor.

The outboard motor should be mounted sothat the boat is well balanced. Otherwise, theboat could be hard to steer. For single-engineboats, mount the outboard motor on the cen-terline (keel line) of the boat.

EMU26921

Mounting heightTo run your boat at optimum efficiency, thewater resistance (drag) of the boat and out-board motor must be made as little as possi-ble. The mounting height of the outboardmotor greatly affects the water resistance. Ifthe mounting height is too high, cavitationtends to occur, thus reducing the propulsion;and if the propeller tips cut the air, the enginespeed will rise abnormally and cause the en-gine to overheat. If the mounting height is toolow, the water resistance will increase andthereby reduce engine efficiency. Mount theoutboard motor so that the anti-cavitationplate is between the bottom of the boat and alevel 25 mm (1 in.) below it.

1. Center line (keel line)

ZMU017601

ZMU02011

0–25mm(0–1in.)


©2019 Yamaha M


Installation

24

NOTICEECM01630

� During water testing, check the buoyan-cy of the boat, at rest, with its maximumload. Check that the static water level onthe exhaust housing is low enough toprevent water entry into the power headwhen water rises due to waves when theoutboard is not running.

� Incorrect engine height or obstructionsto the smooth flow of water (such as thedesign or condition of the boat, or ac-cessories such as transom ladders ordepth finder transducers) can create air-borne water spray while the boat iscruising. If the motor is operated contin-uously in the presence of airborne waterspray, enough water could enter the en-gine through the intake opening on thecowling to cause severe engine dam-age. Eliminate the cause of the airbornewater spray.

TIP:� The optimum mounting height of the out-

board motor is affected by the boat and mo-tor combination and the desired use. Testruns at different heights can help determinethe optimum mounting height. Consult yourYamaha dealer or boat manufacturer forfurther information on determining the prop-er mounting height.

� For instructions on setting the trim angle ofthe outboard motor, see page 35.

EMU26971

Clamping the outboard motor1. Place the outboard motor on the transom

so that it is positioned as close to the cen-ter as possible. Tighten the transomclamp screws evenly and securely. Oc-casionally check the clamp screws fortightness during operation of the out-

board motor because they could becomeloose due to engine vibration.WARNING! Loose clamp screws couldallow the outboard motor to fall off ormove on the transom. This couldcause loss of control and serious inju-ry. Make sure the transom screws aretightened securely. Occasionallycheck the screws for tightness duringoperation. [EWM00641]

2. If the engine restraint cable attachment isequipped on your engine, an engine re-straint cable or chain should be used. At-tach one end to the engine restraint cableattachment and the other to a securemounting point on the boat. Otherwisethe engine could be completely lost if itaccidentally falls off the transom.

3. Secure the clamp bracket to the transomusing the bolts provided with the out-board (if packed). For details, consult

ZMU02012

ZMU02013


©2019 Yamaha M


Installation

25

your Yamaha dealer. WARNING! Avoidusing bolts, nuts or washers otherthan those contained in the enginepackaging. If used, they must be of atleast the same quality of material andstrength and must be tightened se-curely. After tightening, test run theengine and check their tightness.[EWM00651]


©2019 Yamaha M


Operation

26

EMU36380

First-time operationEMU30174

Breaking in engineYour new engine requires a period of break-into allow mating surfaces of moving parts towear in evenly. Correct break-in will help en-sure proper performance and longer enginelife. NOTICE: Failure to follow the break-inprocedure could result in reduced enginelife or even severe engine damage. [ECM00801]

EMU27050

Gasoline and engine oil mixing chart(25:1)

NOTICEECM00150

Be sure to mix gasoline and oil complete-ly, otherwise the engine may be damaged.

EMU27074

Procedure for pre-mixed modelsRun the engine under load (in gear with a pro-peller installed) for 10 hours as follows.1. First 10 minutes:

Run the engine at the lowest possiblespeed. A fast idle in neutral is best.

2. Next 50 minutes:Do not exceed half throttle (approximate-ly 3000 r/min). Vary engine speed occa-sionally. If you have an easy-planingboat, accelerate at full throttle onto plane,then immediately reduce the throttle to3000 r/min or less.

3. Next two hours:Accelerate at full throttle onto plane, thenreduce engine speed to three-quarterthrottle (approximately 4000 r/min). Varyengine speed occasionally. Run at fullthrottle for one minute, then allow about10 minutes of operation at three-quarterthrottle or less to let the engine cool.

4. Remaining seven hours:Run the engine at any speed. However,avoid operating at full throttle for morethan 5 minutes at a time.

5. After the first 10 hours:Operate the engine normally. Use thestandard premix ratio of gasoline and oil.For details on mixing fuel and oil, seepage 28.

EMU36400

Getting to know your boatDifferent boats handle differently. Operatecautiously while you learn how your boat han-dles under different conditions and with differ-ent trim angles (see page 35).EMU36412

Checks before starting engine

WARNINGEWM01920

If any item in the checks before startingengine is not working properly, have it in-spected and repaired before operating theoutboard motor. Otherwise an accidentcould occur.

NOTICEECM00120

Do not start the engine out of water. Over-heating and serious engine damage canoccur.

EMU37141

Fuel levelBe sure you have plenty of fuel for your trip. Agood rule is to use 1/3 of your fuel to get to thedestination, 1/3 to return, and to keep 1/3 as

1. : Gasoline2. : Engine oil


©2019 Yamaha M


Operation

27

an emergency reserve. With the boat level ona trailer or in the water, check the fuel level.For fuel filling instructions, see page 28.EMU36570

Remove cowlingFor the following checks, remove the topcowling from the engine. To remove the en-gine top cowling, release the lock lever and liftoff the cowling.

EMU36440

Fuel system

WARNINGEWM00060

Gasoline and its vapors are highly flam-mable and explosive. Keep away fromsparks, cigarettes, flames, or other sourc-es of ignition.

WARNINGEWM00910

Leaking fuel can result in fire or explosion.� Check for fuel leakage regularly.� If any fuel leakage is found, the fuel sys-

tem must be repaired by a qualified me-chanic. Improper repairs can make theoutboard unsafe to operate.

EMU36450

Check for fuel leaks� Check under top cowling and in the boat for

fuel leaks or gasoline fumes.� Check fuel line connections to be sure they

are tight.

� Check fuel lines for cracks, swelling, or oth-er damage.

EMU37320

Check the fuel filterCheck that the fuel filter is clean and free ofwater. If any water is found in the fuel, or if asignificant amount of debris is found, the fueltank should be checked and cleaned by aYamaha dealer.

EMU36890

Controls� Turn the tiller handle fully to the left and

right to make sure operation is smooth.� Turn the throttle grip from the fully closed to

the fully open position. Make sure that itturns smoothly and that it completely re-turns to the fully closed position.

� Look for loose or damaged connections ofthe throttle and shift cables under the en-gine cowling.

EMU36481

Engine shut-off cord (lanyard)Inspect the engine shut-off cord for damage,such as cuts, breaks, and wear.

ZMU06092


©2019 Yamaha M


Operation

28

EMU27120

Oil� Check to be sure you have plenty of oil for

your trip.EMU27140

Engine� Check the engine and engine mounting.� Look for loose or damaged fasteners.� Check the propeller for damage.EMU36952

Install cowling1. Be sure that a cowling lock lever is re-

leased.2. Be sure that the rubber seal is seated all

the way around the engine.3. Place the cowling on top of the seal.4. Check to be sure the rubber seal fits cor-

rectly all the way around the engine.5. Move the lever to lock the cowling as

shown. NOTICE: If the cowling is notinstalled correctly, water spray underthe cowling can damage the engine, orthe cowling can blow off at highspeeds. [ECM01990]

After installing, check the fitting of the topcowling by pushing it with both hands. If thetop cowling is loose, have it repaired by yourYamaha dealer.

EMU27234

Filling fuel and engine oilEMU27246

Filling fuel for portable tank

WARNINGEWM01830

� Gasoline and its vapors are highly flam-mable and explosive. Always refuel ac-cording to this procedure to reduce therisk of fire and explosion.

� Gasoline is poisonous and can cause in-jury or death. Handle gasoline with care.Never siphon gasoline by mouth. If youshould swallow some gasoline or inhalea lot of gasoline vapor, or get some gas-oline in your eyes, see your doctor im-mediately. If gasoline spills on your

1. Cord2. Clip3. Engine shut-off switch

ZMU06117


©2019 Yamaha M


Operation

29

skin, wash with soap and water. If gaso-line spills on your clothing, change yourclothes.

1. Stop the engine.2. Remove the portable tank from the boat.3. Be sure you are in a well-ventilated out-

door area, either securely moored or trail-ered.

4. Do not smoke and keep away fromsparks, flames, static electric discharge,or other sources of ignition.

5. If you use a portable container to storeand dispense fuel, use only an approvedGASOLINE container.

6. Touch the fuel nozzle to the filler openingor funnel to help prevent electrostaticsparks.

7. Fill the fuel tank, but do not overfill. Fuelcan expand and overflow if the tempera-ture increases.

8. Tighten the filler cap securely.9. Wipe up any spilled gasoline immediately

with dry rags. Dispose rags properly. Ac-cording to local laws or regulations.

EMU27406

Gasoline and oil mixing (100:1)

NOTICEECM00811

� Avoid using any oil other than the spec-ified type.

� Use a thoroughly blended fuel-oil mix-ture.

� If the mixture is not thoroughly mixed, orif the mixing ratio is incorrect, the fol-lowing problems could occur.

� Low oil ratio: Lack of oil could cause ma-jor engine trouble, such as piston sei-zure.

� High oil ratio: Too much oil could causefouled spark plugs, smoky exhaust, andheavy carbon deposits.

If equipped with a portable fuel tank1. Pour oil into the portable fuel tank, and

then add gasoline.

Fuel tank capacity:24.0 L (6.34 US gal, 5.28 Imp.gal)

Gasoline to engine oil ratio

Break-in period See page 26

After break-in 100:1

1. : Gasoline2. : Engine oil

100:11 L

(0.26 US gal, 0.22 Imp gal)

12 L


14 L


24 L


0.01 L

(0.01 US qt, 0.01 Imp qt)

0.12 L

(0.13 US qt, 0.11 Imp qt)

0.14 L

(0.15 US qt, 0.12 Imp qt)

0.24 L

(0.25 US qt, 0.21 Imp qt)

ZMU04910


©2019 Yamaha M


Operation

30

2. Replace the fuel tank cap and close tight-ly.

3. Shake the fuel tank to mix the fuel thor-oughly.

4. Make sure that the oil and gasoline aremixed.

If equipped with a built-in fuel tank1. Pour oil into a clean fuel can, and then

add gasoline.2. Replace the fuel can cap and close tight-

ly.3. Shake the fuel can to mix the fuel thor-

oughly.4. Make sure that the oil and gasoline are

mixed.5. Pour the gasoline and oil mixture into the

built-in fuel tank.

TIP:If using a permanently installed tank, pour theoil gradually as the gasoline is being added tothe tank.EMU27451

Operating engineEMU27464

Feeding fuel (portable tank)

WARNINGEWM00420

� Before starting the engine, make surethat the boat is tightly moored and thatyou can steer clear of any obstructions.Be sure there are no swimmers in thewater near you.

� When the air vent screw is loosened,gasoline vapor will be released. Gaso-line is highly flammable, and its vaporsare flammable and explosive. Refrainfrom smoking, and keep away fromopen flames and sparks while looseningthe air vent screw.

� This product emits exhaust gases whichcontain carbon monoxide, a colorless,odorless gas which could cause braindamage or death when inhaled. Symp-toms include nausea, dizziness, anddrowsiness. Keep cockpit and cabin ar-eas well ventilated. Avoid blocking ex-haust outlets.

1. If there is an air vent screw on the fueltank cap, loosen it 2 or 3 turns.

1. Engine oil2. Gasoline


©2019 Yamaha M


Operation

31

2. If there is a fuel joint on the motor, firmlyconnect the fuel line to the joint. Thenfirmly connect the other end of the fuelline to the joint on the fuel tank.

3. Squeeze the primer pump, with the arrowpointing up, until you feel it become firm.During engine operation place the tankhorizontally, otherwise fuel cannot bedrawn from the fuel tank.

EMU27492

Starting engine

WARNINGEWM01600

Before starting the engine, make sure thatthe boat is tightly moored and that you cansteer clear of any obstructions. Be surethere are no swimmers in the water nearyou.

EMU27532

Manual start models

WARNINGEWM01840

� Failure to attached engine shut-off cordcould result in a runaway boat if opera-tor is ejected. Attach the engine shut-offcord to a secure place on your clothing,or your arm or leg while operating. Donot attach the cord to clothing that couldtear loose. Do not route the cord whereit could become entangled, preventing itfrom functioning.

� Avoid accidentally pulling the cord dur-ing normal operation. Loss of enginepower means the loss of most steeringcontrol. Also, without engine power, theboat could slow rapidly. This couldcause people and objects in the boat tobe thrown forward.

1. Place the gear shift lever in neutral.

ZMU02295

ZMU02024

1. Arrow


©2019 Yamaha M


Operation

32

TIP:The start-in-gear protection device preventsthe engine from starting except when in neu-tral.2. Attach the engine shut-off cord to a se-

cure place on your clothing, or your armor leg. Then install the clip on the otherend of the cord into the engine shut-offswitch.

3. Place the throttle grip in the “ ”(start) position.

4. Pull out / turn the choke knob fully. Placethe choke knob back in to the second orthird position to warm up the engine afterstarting. When the engine has fullywarmed up, replace the choke knob backin to its home position.

TIP:� It is not necessary to use the choke when

starting a warm engine.� If the choke knob is left in the pulled out po-

sition while the engine is running, the en-gine will run poorly or stall.

5. Pull the manual starter handle slowly untilyou feel resistance. Then give a strongpull straight out to crank and start the en-gine. Repeat if necessary.

6. After the engine starts, slowly return themanual starter handle to its original posi-tion before releasing it.

7. Slowly return the throttle grip to the fullyclosed position.


©2019 Yamaha M


Operation

33

TIP:� When the engine is cold, it needs to be

warmed up. For further information, seepage 33.

� If the engine does not start on the first try,repeat the procedure. If the engine fails tostart after 4 or 5 tries, open the throttle asmall amount (between 1/8 and 1/4) and tryagain. Also if the engine is warm and fails tostart, open the throttle a same amount andtry to start the engine again. If the enginestill fails to start, see page 54.

EMU36510

Checks after starting engineEMU36520

Cooling waterCheck for a steady flow of water from the cool-ing water pilot hole. A continuous flow of waterfrom the pilot hole shows that the water pumpis pumping water through the cooling passag-es. If the cooling passages are frozen, it maytake a while for water to start flowing out of thepilot hole.

NOTICEECM01810

If water is not flowing out of the pilot holeat all times while the engine is running,overheating and serious damage couldoccur. Stop the engine and check whetherthe cooling water inlet on the lower case orthe cooling water pilot hole is blocked.Consult your Yamaha dealer if the prob-lem cannot be located and corrected.

Check that no water leaks from the joints be-tween the exhaust cover, cylinder head, andbody cylinder.EMU27670

Warming up engineEMU27683

Choke start modelsAfter starting the engine, allow it to idle for 3minutes to warm up. Failure to do so willshorten engine life. Gradually return thechoke knob to its home position as the enginewarms up.EMU36530

Checks after engine warm-upEMU36540

ShiftingWhile tightly moored, and without applyingthrottle, confirm that the engine shifts smooth-ly into forward and reverse, and back to neu-tral.EMU36970

Stop switches� Press the engine stop button and make

sure the engine stops.� Confirm that removing the clip from the en-

gine shut-off switch stops the engine.� Confirm that the engine cannot be started

with the clip removed from the engine shut-off switch.

ZMU02856


©2019 Yamaha M


Operation

34

EMU34550

Shifting

WARNINGEWM00180

Before shifting, make sure there are noswimmers or obstacles in the water nearyou.

NOTICEECM01610

Warm up the engine before shifting intogear. Until the engine is warm, the idlespeed may be higher than normal. Highidle speed can prevent you from shiftingback to neutral. If this occurs, stop the en-gine, shift to neutral, then restart the en-gine and allow it to warm up.

To shift out of neutralMove the gear shift lever firmly and crisply for-ward (for forward gear) or backward (for re-verse gear). Be sure to check that the tilt locklever is in the lock/down position (if equipped)before operating in reverse.

To shift from in gear (forward/reverse) to neu-tral1. Close the throttle so that the engine

slows to idle speed.

2. After the engine is at idle speed in gearmove the gear shift lever firmly and crisp-ly into the neutral position.

ZMU02030


©2019 Yamaha M


Operation

35

EMU31742

Stopping boat

WARNINGEWM01510

� Do not use the reverse function to slowdown or stop the boat as it could causeyou to lose control, be ejected, or impactthe steering wheel or other parts of theboat. This could increase the risk of se-rious injury. It could also damage theshift mechanism.

� Do not shift into reverse while travelingat planing speeds. Loss of control, boatswamping, or damage to the boat couldoccur.

The boat is not equipped with a separatebraking system. Water resistance stops it af-ter the throttle lever is moved back to idle. Thestopping distance varies depending on grossweight, water surface conditions, and wind di-rection.EMU27821

Stopping engineBefore stopping the engine, first let it cool offfor a few minutes at idle or low speed. Stop-ping the engine immediately after operating athigh speed is not recommended.EMU27833

Procedure1. Push and hold the engine stop button un-

til the engine comes to a complete stop.

2. After stopping the engine, tighten the airvent screw on the fuel tank cap and setthe fuel cock lever or knob to the closedposition, if equipped.

3. Disconnect the fuel line if you are usingan external fuel tank.

TIP:If the outboard motor is equipped with an en-gine shut-off cord, the engine can also bestopped by pulling the cord and removing theclip from the engine shut-off switch.EMU27862

Trimming outboard motor

WARNINGEWM00740

Excessive trim for the operating condi-tions (either trim up or trim down) cancause boat instability and can make steer-ing the boat more difficult. This increases

ZMU02301


©2019 Yamaha M


Operation

36

the possibility of an accident. If the boatbegins to feel unstable or is hard to steer,slow down and/or readjust the trim angle.

The trim angle of the outboard motor helpsdetermine the position of the bow of the boatin the water. Correct trim angle will help im-prove performance and fuel economy whilereducing strain on the engine. Correct trim an-gle depends upon the combination of boat,engine, and propeller. Correct trim is also af-fected by variables such as the load in theboat, sea conditions, and running speed.

EMU27872

Adjusting trim angle for manual tilt modelsThere are 4 or 5 holes provided in the clampbracket to adjust the outboard motor trim an-gle.1. Stop the engine.2. Tilt the outboard motor up, and then re-

move the trim rod from the clamp bracket.

3. Reposition the rod in the desired hole.To raise the bow (“trim-out”), move the rodaway from the transom.To lower the bow (“trim-in”), move the rod to-ward the transom.Make test runs with the trim set to different an-gles to find the position that works best foryour boat and operating conditions.

WARNINGEWM00400

� Stop the engine before adjusting thetrim angle.

� Use care to avoid being pinched whenremoving or installing the rod.

� Use caution when trying a trim positionfor the first time. Increase speed gradu-ally and watch for any signs of instabilityor control problems. Improper trim an-gle can cause loss of control.

TIP:The outboard motor trim angle can bechanged approximately 4 degrees by shiftingthe trim rod one hole.EMU27911

Adjusting boat trimWhen the boat is on plane, a bow-up attituderesults in less drag, greater stability and effi-ciency. This is generally when the keel line ofthe boat is up about 3 to 5 degrees. With thebow up, the boat may have a greater tenden-

1. Trim operating angle

ZMU02043

1

1. Trim rod


©2019 Yamaha M


Operation

37

cy to steer to one side or the other. Compen-sate for this as you steer. The trim tab canalso be adjusted to help offset this effect.When the bow of the boat is down, it is easierto accelerate from a standing start onto plane.

Bow UpToo much trim-out puts the bow of the boattoo high in the water. Performance and econ-omy are decreased because the hull of theboat is pushing the water and there is more airdrag. Excessive trim-out can also cause thepropeller to ventilate, which reduces perfor-mance further, and the boat may “porpoise”(hop in the water), which could throw the op-erator and passengers overboard.

Bow DownToo much trim-in causes the boat to “plow”through the water, decreasing fuel economyand making it hard to increase speed. Operat-ing with excessive trim-in at higher speedsalso makes the boat unstable. Resistance at

the bow is greatly increased, heightening thedanger of “bow steering” and making opera-tion difficult and dangerous.

TIP:Depending on the type of boat, the outboardmotor trim angle may have little effect on thetrim of the boat when operating.EMU27934

Tilting up and downIf the engine will be stopped for some time orif the boat is moored in shallows, the outboardmotor should be tilted up to protect the propel-ler and lower casing from damage by collisionwith obstructions, and also to reduce salt cor-rosion.

WARNINGEWM00221

Be sure all people are clear of the out-board motor when tilting up and down,Body parts can be crushed between themotor and the clamp bracket when the mo-tor is trimmed or tilted.

WARNINGEWM00250

Leaking fuel is a fire hazard. If there is afuel joint on the outboard motor, discon-nect the fuel line or close the fuel cock ifthe engine will be tilted for more than a fewminutes. Otherwise fuel may leak.


©2019 Yamaha M


Operation

38

NOTICEECM00241

� Before tilting the outboard motor, stopthe engine by following the procedureon page 35. Never tilt the outboard mo-tor while the engine is running. Severedamage from overheating can result.

� Do not tilt up the engine by pushing thetiller handle (if equipped) because thiscould break the handle.

EMU32661

Procedure for tilting up (manual tilt models)1. Place the gear shift lever in neutral.

2. Place the tilt lock lever (if equipped) in therelease/up position.

3. Pull up the shallow water lever (ifequipped).

4. Hold the rear of the top cowling with onehand and tilt the engine up fully.

5. Push the tilt support knob into the clampbracket. Or the tilt support bar will turn tothe lock position automatically. NOTICE:Do not use the tilt support lever orknob when trailering the boat. The out-board motor could shake loose fromthe tilt support and fall. If the motorcannot be trailered in the normal run-ning position, use an additional sup-port device to secure it in the tiltposition. For more detailed informa-tion, see page 41. [ECM01641]

EMU28022

Procedure for tilting down (manual tilt models)1. Place the tilt lock lever in the re-

lease/down position or return the shallowwater lever to its original position.

2. Slightly tilt the engine up until the tilt sup-port bar is automatically released.

3. Slowly tilt the engine down.


©2019 Yamaha M


Operation

39

EMU28061

Shallow waterEMU28073

Cruising in shallow water (manual tilt models)

WARNINGEWM01781

� Run the boat at the lowest possiblespeed when using the shallow watercruising system. The tilt lock mecha-nism does not work while the shallowwater cruising system is being used. Hit-ting an underwater obstacle couldcause the outboard motor to lift out ofthe water, resulting in loss of control.

� Use extra care when operating in re-verse. Too much reverse thrust cancause the outboard motor to lift out ofthe water, increasing the chance of acci-dent and personal injury.

NOTICEECM00260

Do not tilt the outboard motor up so thatthe cooling water inlet on the lower unit isabove the surface of the water when set-ting up for and cruising in shallow water.Otherwise severe damage from overheat-ing can result.

EMU32741

Procedure1. Place the gear shift lever in neutral.

2. Place the tilt lock lever in the release/upposition.

3. Slightly tilt the outboard motor up. The tiltsupport bar will lock automatically, sup-porting the outboard motor in a partiallyraised position. This outboard motor has2 positions for shallow water cruising.

4. To return the outboard motor to the nor-mal running position, place the gear shiftlever in neutral.

ZMU02868


©2019 Yamaha M


Operation

40

5. Place the tilt lock lever in the lock/downposition, then slightly tilt the outboard mo-tor up until the tilt support bar automati-cally returns to the free position.

6. Slowly lower the outboard motor to thenormal position.

EMU28194

Cruising in other conditionsCruising in salt waterAfter operating in salt water, flush the coolingwater passages with fresh water to preventthem from becoming clogged. Also rinse theoutside of the outboard motor with fresh waterand, if possible, rinse the power head underthe cowling.Cruising in muddy, turbid, or acidic waterYamaha strongly recommends that you usethe optional chromium-plated water pump kit(see page 15) if you use the outboard motor inacidic water or water with a lot of sediment init, such as muddy or turbid (cloudy) water. Af-ter operating in such water, flush the coolingpassages with fresh water to prevent corro-sion. Also rinse the outside of the outboardmotor with fresh water.

ZMU02048


©2019 Yamaha M


Maintenance

41

EMU28226

Transporting and storing out-board motor

WARNINGEWM00692

� USE CARE when transporting fuel tank,whether in a boat or car.

� DO NOT fill fuel container to maximumcapacity. Gasoline will expand consider-ably as it warms up and can build uppressure in the fuel container. This cancause fuel leakage and a potential firehazard.

WARNINGEWM01860

Leaking fuel is a fire hazard. When trans-porting and storing the outboard motor,close the fuel cock to prevent fuel fromleaking. Never get under the engine whileit is tilted. Severe injury could occur if theoutboard motor accidentally falls.

NOTICEECM00660

Do not use the tilt support lever or knobwhen trailering the boat. The outboard mo-tor could shake loose from the tilt supportand fall. If the motor cannot be trailered inthe normal running position, use an addi-tional support device to secure it in the tiltposition.

The outboard motor should be trailered andstored in the normal running position. If thereis insufficient road clearance in this position,then trailer the outboard motor in the tilt posi-tion using a motor support device such as atransom saver bar. Consult your Yamahadealer for further details.

EMU28235

Clamp screw mounting modelsWhen transporting or storing the outboardmotor while removed from a boat, keep theoutboard motor in the attitude shown.

TIP:Place a towel or something similar under theoutboard motor to protect it from damage.EMU30272

Storing outboard motorWhen storing your Yamaha outboard motorfor prolonged periods of time (2 months orlonger), several important procedures mustbe performed to prevent excessive damage.It is advisable to have your outboard motorserviced by an authorized Yamaha dealer pri-or to storage. However, you, the owner, with aminimum of tools, can perform the followingprocedures.


©2019 Yamaha M


Maintenance

42

NOTICEECM01411

� Do not place the outboard motor on itsside before the cooling water hasdrained from it completely, otherwisewater may enter the cylinder through theexhaust port and cause engine trouble.

� Store the outboard motor in a dry, well-ventilated place, not in direct sunlight.

EMU28303

ProcedureEMU28376

Flushing in a test tank

NOTICEECM00300

Do not run the engine without supplying itwith cooling water. Either the engine waterpump will be damaged or the engine willbe damaged from overheating. Beforestarting the engine, be sure to supply wa-ter to the cooling water passages.

1. Wash the outboard motor body usingfresh water. NOTICE: Do not spray wa-ter into the air intake. [ECM01840] For furtherinformation, see page 43.

2. Fill the fuel tank with fresh fuel and addone ounce of “Yamaha Fuel Conditionerand Stabilizer” to each gallon of fuel.

TIP:The use of “Yamaha Fuel Conditioner andStabilizer” eliminates the need to drain thefuel system. Consult your Yamaha dealer orother qualified mechanic if the fuel system isto be drained instead.3. Remove the engine top cowling and si-

lencer cover.4. Install the outboard motor on the test

tank.

5. Fill the tank with fresh water to above thelevel of the anti-cavitation plate. NOTICE:If the fresh water level is below the lev-el of the anti-cavitation plate, or if thewater supply is insufficient, engineseizure may occur. [ECM00291]

6. Cooling system flushing is essential toprevent the cooling system from cloggingup with salt, sand, or dirt. In addition, fog-ging of the engine is mandatory to pre-vent excessive engine damage due torust. Perform the flushing and fogging atthe same time. WARNING! Do nottouch or remove electrical parts whenstarting or during operation. Keephands, hair, and clothes away fromthe flywheel and other rotating partswhile the engine is running. [EWM00091]

7. Run the engine at a fast idle for 10–15minutes in neutral position.

8. Just prior to turning off the engine, quicklyspray “Yamaha Stor-Rite Engine FoggingOil” alternately into each carburetor or thefogging hole of the silencer cover, ifequipped. When properly done, the en-gine will smoke excessively and almoststall.

9. Remove the outboard motor from the testtank.

1. Water surface2. Lowest water level

ZMU02051

1

2


©2019 Yamaha M


Maintenance

43

10. Drain the cooling water completely out ofthe motor. Clean the body thoroughly.

11. Install the silencer cover/cap and topcowling.

EMU28402

Lubrication1. Install the spark plug(s) and torque to

proper specification. For information onspark plug installation, see page 48.

2. Change the gear oil. For instructions, seepage 51. Inspect the oil for the presenceof water that indicates a leaky seal. Sealreplacement should be performed by anauthorized Yamaha dealer prior to use.

3. Grease all grease fittings. For further de-tails, see page 47.

TIP:For long-term storage, fogging the enginewith oil is recommended. Contact yourYamaha dealer for information about foggingoil and procedures for your engine.EMU28423

Cleaning and anticorrosion measures1. Wash down the exterior of the outboard

motor with fresh water and dry off com-pletely. NOTICE: Do not spray waterinto the air intake. [ECM01840]

2. Spray the outboard motor exterior with“Yamaha Silicone Protectant”.

3. Wax the cowling with a non-abrasive waxsuch as “Yamaha Silicone Wax”.

EMU28450

Cleaning the outboard motorAfter use, wash the exterior of the outboardmotor with fresh water. Flush the cooling sys-tem with fresh water.

TIP:For cooling system flushing instructions, seepage 41.EMU28460

Checking painted surface of motorCheck the motor for scratches, nicks, or flak-ing paint. Areas with damaged paint are morelikely to corrode. If necessary, clean and paintthe areas. A touch-up paint is available fromyour Yamaha dealer.EMU37081

Periodic maintenance

WARNINGEWM01981

These procedures require mechanicalskills, tools, and supplies. If you do nothave the proper skills, tools, or supplies toperform a maintenance procedure, have aYamaha dealer or other qualified mechan-ic do the work.The procedures involve disassemblingthe motor and exposing dangerous parts.To reduce the risk of injury from moving,hot, or electrical parts:� Turn off the engine and keep engine

shut-off cord (lanyard) with you whenyou perform maintenance unless other-wise specified.

� Allow the engine to cool before handlinghot parts or fluids.


©2019 Yamaha M


Maintenance

44

� Always completely reassemble the mo-tor before operation.

Maintenance, replacement, or repair of theemission control devices and systemsmay be performed by any marine enginerepair establishment or individual. All war-ranty repairs, however, including those tothe emission control system, must be per-formed by an authorized Yamaha marinedealership.A service manual is available for purchasethrough your Yamaha dealer for owners whohave the mechanical skills, tools, and otherequipment necessary to perform mainte-nance not covered by this owner’s manual.EMU28511

Replacement partsIf replacement parts are necessary, use onlygenuine Yamaha parts or parts of equivalentdesign and quality. Any part of inferior qualitymay malfunction, and the resulting loss ofcontrol could endanger the operator and pas-sengers. Yamaha genuine parts and acces-sories are available from your Yamahadealer.EMU35520

Maintenance interval guidelinesThe service intervals provided in the Mainte-nance Chart were developed based upon“typical” use that includes operating at variedspeeds, with sufficient time for engine warmup and cool-down, a medium to light load, andan average cruising speed near the 3000 to4000 rpm range. As with any engine, howev-er, if your normal operating conditions are dif-ferent, you should consider service moreoften than shown, especially how often youchange your engine and gear oil. Examplesmight include extended wide-open-throttleuse or long periods of trolling or idling, carry-ing heavy loads, or frequent starting and stop-ping or shifting. More frequent maintenance

will often pay off many times over in increasedengine life and greater owner satisfaction.Consult your Yamaha dealer for additionalmaintenance recommendations.


©2019 Yamaha M


Maintenance

45

EMU34445

Maintenance chart 1TIP:� Refer to the sections in this chapter for explanations of each owner-specific action.� The maintenance cycle on these charts assume usage of 100 hours per year and regular

flushing of the cooling water passages. Maintenance frequency should be adjusted when op-erating the engine under adverse conditions such as extended trolling.

� Disassembly or repairs may be necessary depending on the outcome of maintenancechecks.

� Expendable or consumable parts and lubricants will lose their effectiveness over time andthrough normal usage regardless of the warranty period.

� When operating in salt water, muddy, other turbid (cloudy), acidic water, the engine shouldbe flushed with clean water after each use.

The “ ” symbol indicates the check-ups which you may carry out yourself.The “ ” symbol indicates work to be carried out by your Yamaha dealer.

Item Actions

Initial Every

20 hours (3 months)

100 hours (1 year)

300 hours (3 years)

500 hours (5 years)

Anode(s) (external) Inspection or replace-ment as necessary

Anode(s) (cylinder head, thermostat cov-er)

Inspection or replace-ment as necessary

Anodes (exhaust cover, cooling water passage cover, Rectifier Regula-tor cover)

Replacement

Cooling water leakage Inspection or replace-ment as necessary

Cowling clamp Inspection

Engine starting condi-tion/Noise Inspection

Engine idling speed/Noise Inspection

Fuel filter (can be dis-assembled)


Fuel line(High pres-sure) Inspection

Fuel line(High pres-sure)


Fuel line(Low pres-sure) Inspection

Fuel line(Low pres-sure)



©2019 Yamaha M


Maintenance

46

EMU34451

Maintenance chart 2

Fuel pump Inspection or replace-ment as necessary

Fuel/oil leakage Inspection

Gear oil Replacement

Greasing points Greasing

Impeller/water pump housing


Impeller/water pump housing Replacement

Propeller/Propeller nut/Cotter pin


Shift link/shift cableInspection, adjustment or replacement as nec-essary

Spark plug(s) Inspection or replace-ment as necessary

Spark plug caps/high tension cords


Water from the cooling water pilot hole Inspection

Throttle link/Throttle cable/Throttle pick-up timing

Inspection, adjustment or replacement as nec-essary

Thermostat Inspection or replace-ment as necessary

Water inlet Inspection

Main switch/stop switch/choke switch


Wire harness connec-tions/Wire coupler con-nections


(Yamaha) Fuel tank Inspection and clean-ing as necessary

Item ActionsEvery

1000 hours

Guide exhaust/ex-haust manifold


Item Actions

Initial Every

20 hours (3 months)

100 hours (1 year)

300 hours (3 years)

500 hours (5 years)


©2019 Yamaha M


Maintenance

48

EMU28955

Cleaning and adjusting spark plugThe spark plug is an important engine compo-nent and is easy to inspect. The condition ofthe spark plug can indicate something aboutthe condition of the engine. For example, if thecenter electrode porcelain is very white, thiscould indicate an intake air leak or carburetionproblem in that cylinder. Do not attempt to di-agnose any problems yourself. Instead, takethe outboard motor to a Yamaha dealer. Youshould periodically remove and inspect thespark plug because heat and deposits willcause the spark plug to slowly break downand erode. If electrode erosion becomes ex-cessive, or if carbon and other deposits areexcessive, you should replace the spark plugwith another of the correct type.1. Remove the spark plug caps from the

spark plugs.2. Remove the spark plug. If electrode ero-

sion becomes excessive, or if carbon andother deposits are excessive, you shouldreplace the spark plug with another of thecorrect type. WARNING! When remov-ing or installing a spark plug, be care-ful not to damage the insulator. Adamaged insulator could allow exter-nal sparks, which could lead to explo-sion or fire. [EWM00561]

3. Be sure to use the specified spark plug,otherwise the engine may not operateproperly. Before fitting the spark plug,measure the electrode gap with a wirethickness gauge; adjust the gap to speci-fication if necessary.

4. When fitting the plug, wipe off any dirtfrom the threads, and then screw it in tothe correct torque.

TIP:If a torque-wrench is not available when youare fitting a spark plug, a good estimate of thecorrect torque is 1/4 to 1/2 a turn past finger-tight. Have the spark plug adjusted to the cor-rect torque as soon as possible with a torque-wrench.EMU37450

Checking fuel filterCheck the fuel filter periodically. If any wateror foreign matter is found in the filter, clean orreplace it. For cleaning or replacement of thefuel filter, consult your Yamaha dealer.EMU29041

Inspecting idling speed

WARNINGEWM00451

� Do not touch or remove electrical partswhen starting or during operation.

Standard spark plug:B7HS-10

1. Spark plug gap2. Spark plug part number3. Spark plug I.D. mark (NGK)

Spark plug gap:0.9–1.0 mm (0.035–0.039 in)

Spark plug torque:25.0 Nm (2.55 kgf-m, 18.4 ft-lb)


©2019 Yamaha M


Maintenance

49

� Keep hands, hair, and clothes away fromthe flywheel and other rotating partswhile the engine is running.

NOTICEECM00490

This procedure must be performed whilethe outboard motor is in the water. A flush-ing attachment or test tank can be used.

A diagnostic tachometer should be used forthis procedure. Results may vary dependingon whether testing is conducted with theflushing attachment, in a test tank, or with theoutboard motor in the water.1. Start the engine and allow it to warm up

fully in neutral until it is running smoothly.

TIP:Correct idling speed inspection is only possi-ble if the engine is fully warmed up. If notwarmed up fully, the idle speed will measurehigher than normal. If you have difficulty veri-fying the idle speed, or the idle speed requiresadjustment, consult a Yamaha dealer or otherqualified mechanic.2. Verify whether the idle speed is set to

specification. For idle speed specifica-tions, see page 12.

EMU29112

Checking wiring and connectors� Check that each grounding wire is properly

secured.� Check that each connector is engaged se-

curely.

EMU32111

Checking propeller

WARNINGEWM01880

You could be seriously injured if the en-gine accidentally starts when you are nearthe propeller.� Before inspecting, removing, or install-

ing the propeller, place the shift controlin neutral, turn the main switch to “ ”(off) and remove the key, and removethe clip from the engine shut-off switch.Turn off the battery cut-off switch if yourboat has one.

Do not use your hand to hold the propellerwhen loosening or tightening the propellernut. Put a wood block between the anti-cavi-tation plate and the propeller to prevent thepropeller from turning.

Checkpoints

ZMU02087

ZMU01897


©2019 Yamaha M


Maintenance

50

� Check each of the propeller blades forwear, erosion from cavitation or ventilation,or other damage.

� Check the propeller shaft for damage.� Check the splines for wear or damage.� Check for fish line tangled around the pro-

peller shaft.

� Check the propeller shaft oil seal for dam-age.

EMU30661

Removing propellerEMU29197

Spline models1. Straighten the cotter pin and pull it out us-

ing a pair of pliers.2. Remove the propeller nut, washer, and

spacer (if equipped). WARNING! Do notuse your hand to hold the propellerwhen loosening the propeller nut.[EWM01890]

3. Remove the propeller, washer (ifequipped), and thrust washer.

EMU30671

Installing propellerEMU29233

Spline models

NOTICEECM00500

Be sure to use a new cotter pin and bendthe ends over securely. Otherwise the pro-peller could come off during operation andbe lost.

1. Apply Yamaha marine grease or a corro-sion resistant grease to the propellershaft.

2. Install the spacer (if equipped), thrustwasher, washer (if equipped), and pro-peller on the propeller shaft. NOTICE: Besure to install the thrust washer beforeinstalling the propeller, otherwise thelower case and propeller boss couldbe damaged. [ECM01880]

3. Install the spacer (if equipped) and thewasher. Tighten the propeller nut to thespecified torque.

4. Align the propeller nut with the propellershaft hole. Insert a new cotter pin in thehole and bend the cotter pin ends.NOTICE: Do not reuse the cotter pininstalled. Otherwise the propeller cancome off during operation. [ECM01890]

1. Cotter pin2. Propeller nut3. Washer

ZMU02877

23

45

1

4. Propeller5. Thrust washer

Propeller nut tightening torque:17.0 Nm (1.73 kgf-m, 12.5 ft-lb)


©2019 Yamaha M


Maintenance

51

TIP:If the propeller nut does not align with the pro-peller shaft hole after tightening to the speci-fied torque, tighten the nut further to align itwith the hole.EMU29287

Changing gear oil

WARNINGEWM00800

� Be sure the outboard motor is securelyfastened to the transom or a stablestand. You could be severely injured ifthe outboard motor falls on you.

� Never get under the lower unit while it istilted, even when the tilt support lever orknob is locked. Severe injury could oc-cur if the outboard motor accidentallyfalls.

1. Tilt the outboard motor so that the gear oildrain screw is at the lowest point possi-ble.

2. Place a suitable container under the gearcase.

3. Remove the gear oil drain screw and gas-ket. NOTICE: If there is an excessivequantity of metal particles on the mag-netic gear oil drain screw, this can in-dicate lower unit problem. Consultyour Yamaha dealer. [ECM01900]

TIP:� If a magnetic gear oil drain screw is

equipped, remove all metal particles fromthe screw before installing it.

� Always use new gaskets. Do not reuse theremoved gaskets.

4. Remove the oil level plug and gasket toallow the oil to drain completely.NOTICE: Inspect the used oil after ithas been drained. If the oil is milky,water is getting into the gear casewhich can cause gear damage. Con-sult a Yamaha dealer for repair of thelower unit seals. [ECM00711]

TIP:For disposal of used oil, consult your Yamahadealer.5. Put the outboard motor in a vertical posi-

tion. Using a flexible or pressurized fillingdevice, inject the gear oil into the gear oildrain screw hole.

1. Gear oil drain screw2. Oil level plug

Recommended gear oil:Hypoid gear oil SAE#90

Gear oil quantity:0.250 L (0.264 US qt, 0.220 Imp.qt)

ZMU02064

2

1


©2019 Yamaha M


Maintenance

52

6. Put a new gasket on the oil level plug.When the oil begins to flow out of the oillevel plug hole, insert and tighten the oillevel plug.

7. Put a new gasket on the gear oil drainscrew. Insert and tighten the gear oildrain screw.

EMU29302

Cleaning fuel tank

WARNINGEWM00920

Gasoline is highly flammable, and its va-pors are flammable and explosive.� If you have any question about properly

doing this procedure, consult yourYamaha dealer.

� Keep away from sparks, cigarettes,flames, or other sources of ignitionwhen cleaning the fuel tank.

� Remove the fuel tank from the boat be-fore cleaning it. Work only outdoors inan area with good ventilation.

� Wipe up any spilled fuel immediately.

� Reassemble the fuel tank carefully. Im-proper assembly can result in a fuelleak, which could result in a fire or ex-plosion hazard.

� Dispose of old gasoline according to lo-cal regulations.

1. Empty the fuel tank into an approved con-tainer.

2. Pour a small amount of suitable solventinto the tank. Install the cap and shakethe tank. Drain the solvent completely.

3. Remove the screws holding the fuel jointassembly. Pull the assembly out of thetank.

Tightening torque:9.0 Nm (0.92 kgf-m, 6.6 ft-lb)

Tightening torque:9.0 Nm (0.92 kgf-m, 6.6 ft-lb)

ZMU02065

ZMU03231


©2019 Yamaha M


Maintenance

53

4. Clean the filter (located on the end of thesuction pipe) in a suitable cleaning sol-vent. Allow the filter to dry.

5. Replace the gasket with a new one. Re-install the fuel joint assembly and tightenthe screws firmly.

EMU29312

Inspecting and replacing anode(s)Yamaha outboard motors are protected fromcorrosion by sacrificial anodes. Inspect theexternal anodes periodically. Remove scalesfrom the surfaces of the anodes. Consult aYamaha dealer for replacement of externalanodes.

NOTICEECM00720

Do not paint anodes, as this would renderthem ineffective.

TIP:Inspect ground leads attached to external an-odes on equipped models. Consult a Yamahadealer for inspection and replacement of inter-nal anodes attached to the power unit.

ZMU02324ZMU02067


©2019 Yamaha M


Trouble Recovery

54

EMU29427

TroubleshootingA problem in the fuel, compression, or ignitionsystems can cause poor starting, loss of pow-er, or other problems. This section describesbasic checks and possible remedies, and cov-ers all Yamaha outboard motors. Thereforesome items may not apply to your model.If your outboard motor requires repair, bring itto your Yamaha dealer.If the engine trouble-alert indicator is flashing,consult your Yamaha dealer.

Starter will not operate.Q. Is battery capacity weak or low?A. Check battery condition. Use battery of rec-ommended capacity.

Q. Are battery connections loose or corrod-ed?A. Tighten battery cables and clean batteryterminals.

Q. Is fuse for electric start relay or electric cir-cuit blown?A. Check for cause of electric overload andrepair. Replace fuse with one of correct am-perage.

Q. Are starter components faulty?A. Have serviced by a Yamaha dealer.

Q. Is shift lever in gear?A. Shift to neutral.

Engine will not start (starter operates).Q. Is fuel tank empty?A. Fill tank with clean, fresh fuel.

Q. Is fuel contaminated or stale?A. Fill tank with clean, fresh fuel.

Q. Is fuel filter clogged?A. Clean or replace filter.

Q. Is starting procedure incorrect?A. See page 31.

Q. Has fuel pump malfunctioned?A. Have serviced by a Yamaha dealer.

Q. Are spark plug(s) fouled or of incorrecttype?A. Inspect spark plug(s). Clean or replace withrecommended type.

Q. Are spark plug cap(s) fitted incorrectly?A. Check and re-fit cap(s).

Q. Is ignition wiring damaged or poorly con-nected?A. Check wires for wear or breaks. Tighten allloose connections. Replace worn or brokenwires.

Q. Are ignition parts faulty?A. Have serviced by a Yamaha dealer.

Q. Is engine shut-off cord (lanyard) not at-tached?A. Attach cord.

Q. Are engine inner parts damaged?A. Have serviced by a Yamaha dealer.

Engine idles irregularly or stalls.Q. Are spark plug(s) fouled or of incorrecttype?A. Inspect spark plug(s). Clean or replace withrecommended type.

Q. Is fuel system obstructed?


©2019 Yamaha M


Trouble Recovery

55

A. Check for pinched or kinked fuel line or oth-er obstructions in fuel system.



Q. Have ignition parts failed?A. Have serviced by a Yamaha dealer.

Q. Has alert system activated?A. Find and correct cause of alert.

Q. Is spark plug gap incorrect?A. Inspect and adjust as specified.


Q. Is specified engine oil not being used?A. Check and replace oil as specified.

Q. Is thermostat faulty or clogged?A. Have serviced by a Yamaha dealer.

Q. Are carburetor adjustments incorrect?A. Have serviced by a Yamaha dealer.

Q. Is fuel pump damaged?A. Have serviced by a Yamaha dealer.

Q. Is air vent screw on fuel tank closed?A. Open air vent screw.

Q. Is choke knob pulled out?

A. Return to home position.

Q. Is motor angle too high?A. Return to normal operating position.

Q. Is carburetor clogged?A. Have serviced by a Yamaha dealer.

Q. Is fuel joint connection incorrect?A. Connect correctly.

Q. Is throttle valve adjustment incorrect?A. Have serviced by a Yamaha dealer.

Q. Is battery cable disconnected?A. Connect securely.

Alert buzzer sounds or indicator lights.Q. Is cooling system clogged?A. Check water intake for restriction.

Q. Is engine oil level low?A. Fill oil tank with specified engine oil.

Q. Is heat range of spark plug incorrect?A. Inspect spark plug and replace it with rec-ommended type.

Q. Is specified engine oil not being used?A. Check and replace oil with specified type.

Q. Is engine oil contaminated or deteriorated?A. Replace oil with fresh, specified type.

Q. Is oil filter clogged?A. Have serviced by a Yamaha dealer.

Q. Has oil feed/injection pump malfunc-tioned?A. Have serviced by a Yamaha dealer.


©2019 Yamaha M


Trouble Recovery

56

Q. Is load on boat improperly distributed?A. Distribute load to place boat on an evenplane.

Q. Is water pump or thermostat faulty?A. Have serviced by a Yamaha dealer.

Q. Is there excess water in fuel filter cup?A. Drain filter cup.

Engine power loss.Q. Is propeller damaged?A. Have propeller repaired or replaced.

Q. Is propeller pitch or diameter incorrect?A. Install correct propeller to operate outboardat its recommended speed (r/min) range.

Q. Is trim angle incorrect?A. Adjust trim angle to achieve most efficientoperation.

Q. Is motor mounted at incorrect height ontransom?A. Have motor adjusted to proper transomheight.

Q. Has alert system activated?A. Find and correct cause of alert.

Q. Is boat bottom fouled with marine growth?A. Clean boat bottom.

Q. Are spark plug(s) fouled or of incorrecttype?A. Inspect spark plug(s). Clean or replace withrecommended type.

Q. Are weeds or other foreign matter tangledon gear housing?

A. Remove foreign matter and clean lowerunit.

Q. Is fuel system obstructed?A. Check for pinched or kinked fuel line or oth-er obstructions in fuel system.



Q. Is spark plug gap incorrect?A. Inspect and adjust as specified.


Q. Have electrical parts failed?A. Have serviced by a Yamaha dealer.

Q. Is specified fuel not being used?A. Replace fuel with specified type.

Q. Is specified engine oil not being used?A. Check and replace oil with specified type.

Q. Is thermostat faulty or clogged?A. Have serviced by a Yamaha dealer.

Q. Is air vent screw closed?A. Open the air vent screw.

Q. Is fuel pump damaged?A. Have serviced by a Yamaha dealer.

Q. Is fuel joint connection incorrect?


©2019 Yamaha M


Trouble Recovery

57

A. Connect correctly.

Q. Is heat range of spark plug incorrect?A. Inspect spark plug and replace it with rec-ommended type.

Q. Is high pressure fuel pump drive belt bro-ken?A. Have serviced by a Yamaha dealer.

Q. Is engine not responding properly to shiftlever position?A. Have serviced by a Yamaha dealer.

Engine vibrates excessively.Q. Is propeller damaged?A. Have propeller repaired or replaced.

Q. Is propeller shaft damaged?A. Have serviced by a Yamaha dealer.

Q. Are weeds or other foreign matter tangledon propeller?A. Remove and clean propeller.

Q. Is motor mounting bolt loose?A. Tighten bolt.

Q. Is steering pivot loose or damaged?A. Tighten or have serviced by a Yamahadealer.EMU29433

Temporary action in emergencyEMU29440

Impact damage

WARNINGEWM00870

The outboard motor can be seriously dam-aged by a collision while operating ortrailering. Damage could make the out-board motor unsafe to operate.

If the outboard motor hits an object in the wa-ter, follow the procedure below.

1. Stop the engine immediately.2. Inspect the control system and all compo-

nents for damage. Also inspect the boatfor damage.

3. Whether damage is found or not, returnto the nearest harbor slowly and careful-ly.

4. Have a Yamaha dealer inspect the out-board motor before operating it again.

EMU29533

Starter will not operateIf the starter mechanism does not operate(the engine cannot be cranked with the start-er), the engine can be started with an emer-gency starter rope.

WARNINGEWM01022

� Use this procedure only in an emergen-cy to return to the nearest port for re-pairs.

� When the emergency starter rope isused to start the engine, the start-in-gear protection device does not operate.Make sure the remote control lever is inneutral. Otherwise the boat could unex-pectedly start to move, which could re-sult in an accident.

� Attach the engine shut-off cord to a se-cure place on your clothing, or your armor leg while operating the boat.


©2019 Yamaha M


Trouble Recovery

58

� Do not attach the cord to clothing thatcould tear loose. Do not route the cordwhere it could become entangled, pre-venting it from functioning.

� Avoid accidentally pulling the cord dur-ing normal operation. Loss of enginepower means the loss of most steeringcontrol. Also, without engine power, theboat could slow rapidly. This couldcause people and objects in the boat tobe thrown forward.

� Make sure no one is standing behindyou when pulling the starter rope. Itcould whip behind you and injure some-one.

� An unguarded, rotating flywheel is verydangerous. Keep loose clothing andother objects away when starting the en-gine. Use the emergency starter ropeonly as instructed. Do not touch the fly-wheel or other moving parts when theengine is running. Do not install thestarter mechanism or top cowling afterthe engine is running.

� Do not touch the ignition coil, spark plugwire, spark plug cap, or other electricalcomponents when starting or operatingthe motor. You could get an electricalshock.

EMU29562

Emergency starting engine1. Remove the top cowling.2. Remove the start-in-gear protection ca-

ble from the starter, if equipped.3. Remove the starter/flywheel cover after

removing the bolt(s).

4. Prepare the engine for starting. For fur-ther information, see page 31. Be surethe engine is in neutral and that the clip isattached to the engine shut-off switch.The main switch must be “ ” (on), ifequipped.

5. If equipped the choke knob, pull out itwhen the engine is cold. After the enginestarts, gradually return the choke knob toits home position as the engine warmsup.

6. Insert the knotted end of the emergencystarter rope into the notch in the flywheelrotor and wind the rope several turnsaround the flywheel clockwise.

7. Give a strong pull straight out to crankand start the engine. Repeat if neces-sary.


©2019 Yamaha M


Trouble Recovery

59

EMU33501

Treatment of submerged motorIf the outboard motor is submerged, immedi-ately take it to a Yamaha dealer. Otherwisesome corrosion may begin almost immediate-ly. NOTICE: Do not attempt to run the out-board motor until it has been completelyinspected. [ECM00401]


©2019 Yamaha M


YAMAHA OWNER'S MANUALS...Title 9.9 15 Owners Manual Author Yamaha Motor Corporation Subject 9.9 15...

Documents

Transcript of YAMAHA OWNER'S MANUALS...Title 9.9 15 Owners Manual Author Yamaha Motor Corporation Subject 9.9 15...