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Yamaha 25A Owner's Manual

Summary of 25A

  • Page 1

    25a/30a lit-18626-04-54 25a 30a owner’s manual u.S.A.Edition 6l2-9-1h \ 01.4.20 3:05 pm y [ w 1 (2,1).

  • Page 2

    6l2-9-1h \ 01.4.20 3:05 pm y [ w 2 (1,1).

  • Page 3: To The Owner

    E thank you for choosing a yamaha out- board motor. This owner’s manual con- tains information needed for proper oper- ation, maintenance and care. A thorough understanding of these simple instruc- tions will help you obtain maximum enjoyment from your new yamaha. If you have any question about the ...

  • Page 4

    6l2-9-1h 1 4/20/01 1:53 pm page 2.

  • Page 5: General Information

    General information basic components operation maintenance trouble recovery index ema20010 contents read this owner’s manual carefully before operating your outboard motor. 1 2 3 4 5 6 e 6l2-9-1h 1 4/20/01 1:53 pm page 3.

  • Page 6

    6l2-9-1h 1 4/20/01 1:53 pm page 4.

  • Page 7: Chapter 1

    1 2 3 4 5 6 emb00010 chapter 1 general information identification numbers record ..1-1 outboard motor serial number...........1-1 key number...........................................1-1 emission control information...1-2 safety information..........................1-3 important labels ................

  • Page 8: Identification Numbers

    E 1-1 emu00005 identification numbers record emu00007 outboard motor serial num- ber the outboard motor serial number is stamped on the label attached to the port side of the clamp-bracket. Record your outboard motor serial num- ber in the spaces provided to assist you in ordering spare parts from y...

  • Page 9: Emission Control

    E 1-2 1 2 108021 1 2 108022 25 25-3/30 emu01385 emission control information emu01386 north american models this engine conforms to u.S. Environ- mental protection agency (epa) regula- tions for marine si engines. See the label affixed to your engine for details. Approval label of emission control c...

  • Page 10: Safety

    E 1-3 8 this product emits exhaust gases which contain carbon monoxide, a colorless, odorless gas which may cause brain damage or death when inhaled. Symp- toms include nausea, dizziness, and drowsiness. Keep cockpit and cabin areas well ventilated. Avoid blocking exhaust outlets. 8 check throttle, ...

  • Page 11

    E 1-4 8 when a swimmer is in the water near you shift into neutral and shut off the engine. 8 be informed about boating safety. Addi- tional publications and information can be obtained from many organizations, including the following: united states coast guard consumer affairs staff (g-bc) office o...

  • Page 12: Important Labels

    E 1-5 emb30010 important labels warning labels 1 2 202023 q w 202061 q w 202062 q 30 warning this engine is equipped with a neutral starting device. The engine will not start unless the shift control is in neutral position. 6e0-83627-41 warning ● be sure shift control is in neutral before starting e...

  • Page 13: Basic Boating Rules

    E 1-6 emb40010 basic boating rules (rules of the road) just as there are rules which apply when you are driving on streets and high ways, there are waterway rules which apply when you are driving your boat. These rules are used internationally, and are also enforced by the united states coast guard ...

  • Page 14

    E rules when encountering vessels there are three main situations which you may encounter with other vessels which could lead to a collision unless the steer- ing rules are followed: meeting (you are approaching another vessel head-on) crossing (you are travelling across the other vessel’s path) ove...

  • Page 15

    1-8 the other vessel is expected to maintain its course and speed. You must stay out of its way until you are clear of it. Like- wise, if another vessel is passing you, you should maintain your speed and direction so that the other vessel can steer itself around you. Other special situations there a...

  • Page 16

    1-9 tion. 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 geo- graphic location. Always consult local boating authorities before driving your boat in unfamiliar waters. E...

  • Page 17: Fueling Instructions

    1-10 e emu00016 fueling instructions w gasoline and its vapors are high- ly flammable and explosive! 8 do not smoke when refueling, and keep away from sparks, flames, or other sources of ignition. 8 stop engine before refueling. 8 refuel in a well-ventilated area. Refuel portable fuel tanks off the ...

  • Page 18

    1-11 e recommended engine oil: yamalube 2 stroke outboard oil emu00858 engine oil if the recommended engine oil is not available, another 2-stroke engine oil with a nmma-certified tc-w3 rating may be used. Emu00027 gasohol there are two types of gasohol: gasohol containing ethanol and that containin...

  • Page 19: Battery Requirement

    1-12 e minimum cold crank performance 210 amps at -17.8°c (0°f) minimum reserve capacity 40 minutes at 26.7°c (80°f) emu01430 battery requirement c c do not use a battery that does not meet the specified capacity. If a battery which differs from the specification is used, the electrical system may p...

  • Page 20: Propeller Selection

    1-13 e emu01395 propeller selection the performance of your outboard motor will be critically affected by your choice of propeller, as an incorrect choice could adversely affect performance and could also seriously damage the motor. Engine speed depends on the propeller size and boat load. If engine...

  • Page 21: Start-In-Gear Protection

    1-14 e emu01209 start-in-gear protection yamaha outboard motors or yamaha approved remote control units are equipped with start-in-gear protection device(s). This feature permits the engine to be started only when it is neutral. Always select neutral before starting the engine. 602016 10-3/4x17-f 1 ...

  • Page 22: -Memo-

    E -memo- 6l2-9-1h 1 4/20/01 1:53 pm page 20

  • Page 23: Chapter 2

    Emc00010 chapter 2 basic components main components..............................2-1 operations of controls and other functions ................................2-3 fuel tank ................................................2-3 gear shift lever .....................................2-3 engine stop lany...

  • Page 24: Main Components

    E 2-1 emu01206 main components 101061 !1 !0 !6 !2 !4 u i q r w t y e !3 o !5 1 recoil starter handle 2 choke knob 3 warning lamp 4 gear shift lever 5 throttle-control grip/tiller-handle 6 engine stop button/ engine stop lanyard switch 7 transom-clamp handle 8 tilt lock lever 9 cooling water inlet 0 ...

  • Page 25: Main Components

    2-2 e emu01206 main components 701061 101113** t y u r w e 101111 q i !0 o !2 !8 !4 !5 !6 !7 @0 !3 w e !1 !9 @1 1 top cowling 2 tilt-lock lever 3 transom-clamp handle 4 anti-cavitation plate 5 trim tab 6 cooling water inlet 7 propeller * 8 battery lead 9 trim angle adjusting rod 0 clamp bracket q wi...

  • Page 26: Operations of Controls

    2-3 e q w e r 902051 406015 q w e emc20010 operations of controls and other functions emc21012 fuel tank if your model was equipped with a portable fuel tank, its function is as fol- lows. 1 fuel hose joint 2 fuel meter(if equipped) 3 fuel tank cap 4 air vent screw(if equipped) fuel hose joint this ...

  • Page 27

    2-4 e emc28111 engine stop lanyard switch (for tiller control model) the lock-plate on the end of the lanyard must be attached to the engine stop switch for the engine to run. The lanyard should be attached to a secure place on the operator’s clothing, or arm or leg. Should the operator fall overboa...

  • Page 28

    2-5 emc27011 engine stop button (for tiller control model) pushing this button opens the ignition cir- cuit and stops the engine. Emu00062 tiller handle (for tiller control model) moving the tiller handle sideways to adjust the steering direction. In addition, this handle contains the functions as f...

  • Page 29

    2-6 e 502011 emu01293 throttle friction adjusting screw/ knob a friction device in the tiller handle pro- vide resistance to movement of the throt- tle grip. This is adjustable for operator preference. An adjusting screw/knob is located within the tiller handle. When constant speed is desired, tight...

  • Page 30

    2-7 emc46010 starter button (for tiller control model) when you push the starter button, the electric starter motor cranks the engine to start it. E 306014 30 emu00090 remote control both the shifter and the throttle are actu- ated by the remote control lever. In addi- tion, this remote control also...

  • Page 31

    2-8 e neutral interlock trigger to shift out of neutral, the neutral inter- lock trigger of the remote control lever must first be pulled up. 701036 701033* n q w neutral throttle lever to open the throttle without shifting into either forward or reverse, place the remote control lever in the neutra...

  • Page 32

    2-9 emc50310 choke switch while the main switch is being pressed in at “on” or “start”, the choke system will switch on, to supply a rich mixture required to start the engine. (when the key is released, it will switch off automatically.) e start off on 701042 emu00934 engine stop lanyard switch the ...

  • Page 33

    2-10 e 701035 resistance screw increase turn clockwise decrease turn counterclockwise emu01155 throttle friction adjusting screw a friction device in the remote control box provides adjustable resistance to move- ment of the remote control lever, and can be set according to operator preference. An a...

  • Page 34

    Emu00113 trim tab the trim tab should be adjusted so that the steering control can be turned to either the right or left by applying the same amount of force. W an improperly adjusted trim tab may cause difficult steering. Always test run after the trim tab has been installed or replaced to be sure ...

  • Page 35

    2-12 emd08010 shallow water lever (if equipped) 25 lifting this lever will tilt the motor up par- tially to provide more clearance when operating in shallow water. E 402075* 25 402072* 25-3/30 emd08110 shallow water lever (if equipped) 25-3/30 pushing this lever down will tilt the motor up partially...

  • Page 36

    2-13 emd62010 top cowling lock lever to remove the engine top cowling, push the lock lever downward. Then lift off the cowling. When replacing the cowling, check to be sure it fits properly in the rub- ber seal. Then lock the cowling again by moving the lever upward. E 403023 q 403024 25 25-3/30 emd...

  • Page 37: Warning System

    2-14 e emd80010 warning system c c do not continue to operate the engine if the warning device has activated. Consult your yamaha dealer if the problem can- not be located and corrected. 303013 303014 25 25-3/30 emu00170 overheat warning this engine has an overheat warning device. If the engine temp...

  • Page 38

    2-15 e 213023 q 303014 30 emu00172 oil level warning / oil filter clogging warning this engine has an oil level warning sys- tem. If oil level falls below lower limit, the warning device will activate. ( 2 ); included ( — ); n/a if the warning system has been activated, stop the engine and check for...

  • Page 39

    2-16 e oil level warning system 30 the various oil-level warning system functions are as follows: oil level warning indicator lamp (bottom cowling) remarks engine oil tank off no refilling necessary. More than 200 cm 3 (0.21 us qt, 0.181 imp qt) red on buzzer sounds in remote control box and engine ...

  • Page 40: -Memo-

    E -memo- 6l2-9-1h 2 4/20/01 1:53 pm page 18.

  • Page 41: Chapter 3

    Emf00010 chapter 3 operation installation ........................................3-1 mounting the outboard motor............3-2 clamping the outboard motor.....3-4, 3-5 filling fuel and engine oil ............3-6 filling fuel..............................................3-6 filling oil ...............

  • Page 42: Installation

    3-1 e emf10010 installation c c incorrect engine height or obstructions to smooth water flow (such as the design or condition of the boat or accessories such as transom ladders/depth finder trans- ducers) can create airborne water spray while the boat is cruising. Severe engine damage may result if ...

  • Page 43

    3-2 emu00176 mounting the outboard motor w improper mounting of the outboard motor could result in hazardous condi- tions such as poor handling, loss of con- trol, or fire hazards. Observe the follow- ing: 8 the information presented in this sec- tion is intended as reference only. It is not possibl...

  • Page 44

    3-3 w overpowering a boat may cause severe instability. Do not install an outboard motor with more horsepower than the maximum rating on the capacity plate of the boat. If the boat does not have a capacity plate, consult the boat manufac- turer. E 104013 0~25mm emu01298 mounting height to run your b...

  • Page 45

    3-4 emf14010 clamping the outboard motor 1) place the outboard on the transom so that it is positioned as close to the center as possible. Tighten the tran- som clamp screws evenly and secure- ly. Check the clamp-screws for tight- ness occasionally during operation of the motor as they can work loos...

  • Page 46

    3-5 emu01318 clamping the outboard motor 30eh/30er 1) place the outboard on the transom so that it is positioned as close to the center as possible. Tighten the tran- som clamp screws evenly and secure- ly. Check the clamp-screws for tight- ness occasionally during operation of the motor as they can...

  • Page 47: Filling Fuel and

    3-6 emf30010 filling fuel and engine oil filling fuel 1) remove the fuel tank cap. 2) fill the fuel tank carefully. 3) close the cap securely after refueling. Wipe up any spilled fuel. Ring free fuel additive gasoline is a precise blend of many differ- ent substances, each chosen to give cer- tain c...

  • Page 48

    3-7 while many additives available may reduce deposits, yamaha recommends the use of ring free fuel additive, avail- able from your yamaha dealer. Ring free has repeatedly proven its ability to clean combustion deposits from inside the engine, notably the critical piston-ring- land area, and fuel sy...

  • Page 49

    3-8 manual start model 1) remove the top cowling. 2) open the oil tank filler cap by pulling the tab. 3) slowly fill the engine oil into the engine oil tank. 4) after filling, replace the cap securely. 5) replace the top cowling securely. 1 engine oil tank 2 oil tank filler cap electric start model ...

  • Page 50

    3-9 emf35011 gasoline (petrol) and oil mixing pre-mix model 1) pour oil and gasoline into the fuel tank, in that order. 1 engione oil 2 gasoline (petrol) 2) then mix the fuel thoroughly by shak- ing. 3) make sure the oil is mixed with gaso- line . C c 8 avoid using any oil other than the des- ignate...

  • Page 51

    3-10 e mixing ratio 25 : 1 gasoline (petrol) engine oil 0.04 l 0.48 l 0.56 l 0.96 l (0.04 us qt, (0.51 us qt, (0.59 us qt, (1.01 us qt, 0.04 imp qt) 0.42 imp qt) 0.49 imp qt) 0.84 imp qt) 1 l 12 l 14 l 24 l (0.26 us gal, (3.2 us gal, (3.7 us gal, (6.3 us gal, 0.22 imp gal) 2.6 imp gal) 3.1 imp gal) ...

  • Page 52: Pre-Operation Checks

    3-11 mu00204 pre-operation checks w if any item in the pre-operation check is not working properly, have it inspected and repaired before operating the out- board motor. Otherwise, an accident could occur. C c do not start the engine out of water. Overheating and serious engine damage can occur. Emu...

  • Page 53

    3-12 e 203024 o il 30 30 emu00210 engine 8 check the engine and engine mounting. 8 look for loose or damaged fasteners. 8 check the propeller for damage. Emf44010 operation after a long period of storage (for precision blend system model) when operating the engine after a long period (12 months) of ...

  • Page 54: Breaking In (Running In)

    3-13 emf50211 breaking in (running in) engine your new engine requires a period of break-in (running-in) to allow mating sur- faces of moving parts to wear-in evenly. Correct break-in (running-in) will help ensure proper performance and longer engine life. C c 8 failure to follow the break-in (runni...

  • Page 55

    3-14 emu00229 run the engine under load (in gear with a propeller installed) as follows. 1) first 10 minutes: run the engine at the lowest possi- ble-speed. A fast idle in neutral is best. 2) next 50 minutes: do not exceed half throttle (approxi- mately 3,000 r/min). Vary engine speed occasionally. ...

  • Page 56: Starting Engine

    3-15 emu01147 starting engine w 8 before starting the engine, make sure that the boat is tightly moored and that you can steer clear of any obstructions. Be sure there are no swimmers in the water near you. 8 when the air vent screw is loosened, gasoline (petrol) vapor will be released. Gasoline (pe...

  • Page 57

    3-16 1) if there is an air vent screw on the fuel tank cap, loosen it 2 or 3 turns. E 902053 25-3/30 304024* 902025 902061 25 n 406012 3) squeeze the primer bulb with the out- let end up until you feel it become firm. 2) if there is a fuel joint on the motor, firmly connect the fuel line to the join...

  • Page 58

    3-17 5) place the throttle control grip in the “start” position. E 407016 308013* 25 25-3/30 503022 6) attach the engine stop switch lanyard to a secure place on your clothing, or your arm or leg. Then, install the lock plate on the other end of the lanyard in the engine stop switch. W 8 attach the ...

  • Page 59

    3-18 8) pull the starter handle slowly until you feel resistance. Then, give a strong pull straight out to crank and start the engine. Repeat it, if neces- sary. 9) after the engine starts, return the starter handle slowly to the original position before releasing it. E 209015 503012 305023* 30eh/30...

  • Page 60

    3-19 10) return the throttle control grip slowly to the fully closed position so that the engine does not stall. C c 8 never push the starter-switch while the engine is running. 8 do not keep the starter motor turning for more than 5 seconds. If the starter- motor is turned continuously for more tha...

  • Page 61

    3-20 w 8 attach the engine stop switch lanyard to a secure place on your clothing, your arm or leg while operating. 8 do not attach the lanyard to clothing that could tear loose. Do not route the lanyard where it could become entan- gled, preventing from functioning. 8 avoid accidentally pulling the...

  • Page 62

    3-21 e start off on 701041 start off on 701042 8) press in and hold the main switch to operate the remote choke system. (the remote choke switch returns to its home position when you release your hand. Therefore, keep the switch pressed in.) note: 8 it is not necessary to use the choke when the engi...

  • Page 63: Warming Up Engine

    3-22 e 309012 eemg00010 warming up engine 1) before beginning operation, allow the engine to warm up at idling speed for 3 minutes. (failure to do this will shorten engine life.) 2) check for a steady flow of water from the cooling-water pilot hole. C c a continuous flow of water from the pilot hole...

  • Page 64: Shifting

    E 3-23 mg20710 shifting w before shifting, make sure there are no swimmers or obstacles in the water near you. C c to change the shifting position from for- ward to reverse or vice-versa, close the throttle first so that the engine idles (or runs at low speeds). Forward tiller control model 1) place...

  • Page 65

    E 3-24 emu01326 reverse w when operating in reverse, go slowly. Do not open the throttle more than half. Oth- erwise, the boat may become unstable, which could result in loss of control and an accident. 1) place the throttle control grip in the fully closed position (for tiller control model). 2) ch...

  • Page 66: Stopping Engine

    E 3-25 eemg38010 stopping engine let it cool off for a few minutes at idle or low speed first. Stopping the engine immediately after operating at high speed is not recommended. Emu00277 1) push and hold the engine stop button or turn the main switch to “off”. 2) if the fuel joints are provided, disc...

  • Page 67: Trimming Outboard

    E 3-26 000910 q emu01412 trimming outboard motor the trim angle of the outboard motor helps determine the position of the bow of the boat in the water. The correct trim angle will help improve performance and fuel economy while reducing strain on the engine. The correct trim angle depends upon the c...

  • Page 68

    E 3-27 adjusting trim angle emu00951 manual tilt model there are 4 or 5 holes provided in the clamp bracket to adjust the outboard motor trim angle. 1) stop the engine. 2) remove the trim angle adjusting rod 1 from the clamp bracket while tilting the motor up slightly. 3) reposition the rod in the d...

  • Page 69

    E 3-28 105011 105013 105015 1 2 3 emu00282 bow up when the boat is on plane, a bow-up atti- tude result in less drag, greater stability and efficiency. This is generally when the keel line of the boat is up about 3 to 5 degrees. When trimmed out, the boat may have more tendency to steer to one side ...

  • Page 70: Cruising In Shallow

    E 3-29 emg70011 cruising in shallow water manual tilt model the outboard motor can be tilted up par- tially to allow operation in shallow water. W 8 place the gear shift in the neutral posi- tion before using the shallow water cruising system. 8 run the boat at the lowest possible speed when using t...

  • Page 71

    E 3-30 3) pull up the shallow water lever. 4) slightly tilt up the engine. The tilt- support bar will lock automatically, supporting the engine in a partially raised position. Note: if the engine is tilted up completely, the tilt-lock lever automatically locks. The shallow water lever is no longer e...

  • Page 72: Tilting Up/down

    E 3-31 emh10110 tilting up/down if the engine will be stopped for some time, or if the boat is moored in shallows, the engine should be tilted up to protect the propeller and casing from damage by collision with obstructions, and also to reduce salt corrosion. C c 8 before tilting the motor, follow ...

  • Page 73

    E 3-32 emg63910 procedure for tilting up 25 1) place the gear shift lever in neutral. 2) remove the fuel line connection from the motor. N 406012 402061** 402075* 3) push the tilt lock lever to release. 4) pull up the shallow water lever. 5) hold the rear of the top cowling with one hand and fully t...

  • Page 74

    E 3-33 402035 403024 402075* 403036 emg73410 procedure for tilting down 25 1) return the shallow water lever. 2) slightly tilt up the engine until the tilt support bar is released automatically. 3) tilt down the engine. Emg73210 procedure for tilting down 25-3/30 1) return the tilt support lever til...

  • Page 75: Cruising In Other

    E 3-34 emh60010 cruising in other conditions cruising in salt water after operating in salt water, wash out the cooling-water passages with fresh water to prevent them from becoming clogged- up with salt deposits. Note: refer to cooling system flushing instruc- tions in “transporting and storing out...

  • Page 76: -Memo-

    E -memo- 6l2-9-1h 3b 4/20/01 1:50 pm page 14.

  • Page 77: Chapter 4

    Emk00010 chapter 4 maintenance specification data.............................4-1 transporting and storing outboard motor ...............................4-4 trailering outboard motor...................4-4 storing outboard motor ......................4-5 periodic maintenance....................4-10 r...

  • Page 78: Specification Data

    4-1 e emk10011* specification data model unit 25mha item 25 (2.5, 18) 35 (3.5, 25) 8spark plug n•m (kgf•m, lb•ft) 8propeller nut n•m (kgf•m, lb•ft) dimensions performance 8overall length mm (in.) 8overall width mm (in.) 8overall height s/l mm (in.) 8transom height s/l mm (in.) 8weight s/l kg (lb.) 9...

  • Page 79

    4-2 e 25mha3 30mha 30eha 25 (2.5, 18) 35 (3.5, 25) 993 (39.1) 360 (14.2) 1,158 (45.6)/— 424 (16.7)/— 59.0 (130.1)/— 4,500~5,500 18.4 (25) at 5,000 r/min 700~800 2-stroke, l 3 496 (30.3) 59.5 × 59.5 (2.3 × 2.3) c.D.I system b7hs-10 0.9~1.0 (0.035~0.039) tiller control manual start — — — 12v-(80w) cho...

  • Page 80: Specification Data

    4-3 e emk10011* specification data model unit 30era item 8spark plug n•m (kgf•m, lb•ft) 8propeller nut n•m (kgf•m, lb•ft) dimensions performance 8overall length mm (in.) 8overall width mm (in.) 8overall height s/l mm (in.) 8transom height s/l mm (in.) 8weight s/l kg (lb.) 8full throttle operating ra...

  • Page 81: Transporting and

    E 4-4 emu01369* transporting and storing outboard motor w leaking fuel is a fire hazard. When trans- porting and storing the outboard motor, close the air vent screw and fuel cock to prevent fuel from leaking. Trailering outboard motor the motor should be trailered and stored in the normal running p...

  • Page 82

    4-5 when transporting or storing the out- board motor while removed from a boat, fold the tiller handle and lean the motor on the tiller handle to keep in a horizontal position. Note: place a towel or the like under the out- board motor to protect it from damage. C c keep the power unit higher than ...

  • Page 83

    4-6 e emk21010 filling fuel tank fill the fuel tank with fresh fuel and add one ounce of “yamaha fuel conditioner and stabilizer” (part no. Lub-fuelc-12- 00) to each gallon of fuel. Note: the use of “yamaha fuel conditioner and stabilizer” eliminates the need to drain the fuel system. Consult your y...

  • Page 84

    4-7 w 8 do not touch or remove electrical parts when starting or during operation. 8 keep hands, hair and clothes away from flywheel and other rotating parts while engine is running. 3) run the engine at a fast idle for 10~15 minutes. 4) just prior to turning off the engine, quickly spray “yamaha st...

  • Page 85

    4-8 e 4) change the lower unit oil. (refer to “changing gear oil”). Inspect the oil for the presence of water which indicates a leaky seal. Seal replace- ment should be performed by an authorized yamaha dealership prior to use. 5) grease all grease fittings. (refer to “greasing”) emk27011 cleaning a...

  • Page 86

    4-9 emu00353 battery care w battery electrolyte is poisonous and dan- gerous, causing severe burns, etc. It con- tains sulfuric acid. Avoid contact with skin, eyes, or clothing. Antidote: external; flush with water. Internal; drink large quantities of water or milk. Follow with milk of mag- nesia, b...

  • Page 87: Periodic Maintenance

    4-10 e emk32110 periodic maintenance w be sure to turn off the engine when you perform maintenance unless otherwise specified. If the owner is not familiar with machine servicing, this work should be done by a yamaha dealer or other quali- fied mechanic. A service manual is available for purchase th...

  • Page 88

    Interval item spark plug(s) cleaning/adjustment/ ● ● ● 4-12 replacement grease points greasing ● 4-19, 4-20, 4-21 fuel system inspection ● ● 4-14 fuel filter cleaning/replacement ● ● ● 4-15 fuel tank *1 cleaning ● 4-25 idling speed inspection/adjustment ● ● 4-16 oil tank water drain cleaning ● ● ● 4...

  • Page 89

    E 4-12 emu01202 cleaning and adjusting spark plug w when removing or installing a spark plug, be careful not to damage the insulator. A damaged insulator could allow external sparks, which could lead to explosion or fire. The spark plug is an important engine component and is easy to inspect. The co...

  • Page 90

    4-13 when fitting the plug, always clean the gasket surface and use a new gasket. Wipe off any dirt from the threads and screw in the spark plug to the correct torque. Note: if a torque-wrench is not available when you are fitting a spark plug, a good esti- mate of the correct torque is 1/4 to 1/2 a...

  • Page 91

    4-14 e emk38010 checking fuel system w gasoline (petrol) and its vapors are highly flammable and explosive. Keep away from sparks, cigarettes, flames or other sources of ignition. Check the fuel line for leaks, cracks, or malfunctions. If any problem is found, it should be repaired immediately by ya...

  • Page 92

    4-15 emu00370 inspecting fuel filter w gasoline (petrol) is highly flammable, and its vapors are flammable and explosive. 8 if you have any question about properly doing this procedure, consult your yamaha dealer. 8 do not perform this procedure on a hot or running engine. Allow the engine to cool. ...

  • Page 93

    4-16 e 5) attach the filter assembly to the bracket with that the fuel hoses are attached to the filter assembly. 6) run the engine and check the filter and lines for leaks. 1 filter element 2 o-ring 3 filter cap 4 filter housing 207013* q w e r emu00376 adjusting idling speed w 8 do not touch or re...

  • Page 94

    4-17 2) adjust the throttle stop-screw to set the idling speed to specification (see “specifications”) by turning the stop-screw clockwise to increase the idling speed, and turning it counter- clockwise to decrease the idling speed. Note: correct idling-speed adjustment is only possible if the engin...

  • Page 95

    4-18 e emu01329 replacing fuse if the fuse has blown on an electric start model, open the fuse holder and replace the fuse with a new one of proper amper- age. W be sure to use the specified fuse. An incorrect fuse or a piece of wire may allow excessive current flow. This could cause electrical syst...

  • Page 96

    4-19 e mu00366 greasing yamaha marine grease (water resistant grease) 25 103141b 6l2-9-1h 4 4/20/01 1:49 pm page 20

  • Page 97

    4-20 e 25-3/30 103141a emu00366 greasing yamaha marine grease (water resistant grease) 6l2-9-1h 4 4/20/01 1:49 pm page 21.

  • Page 98

    4-21 e 30 emu00366 greasing yamaha marine grease (water resistant grease) 6l2-9-1h 4 4/20/01 1:49 pm page 22.

  • Page 99

    4-22 e emu00388 checking propeller w you could be seriously injured if the engine accidentally starts while you are near the propeller. 8 before inspecting, removing or installing the propeller, remove the spark plug caps from the spark plugs. Also, put the shift control in neutral, put the main swi...

  • Page 100

    4-23 e emu00397 installing the propeller c c 8 be sure to install the thrust washer before installing propeller, otherwise, lower case and propeller boss may be damaged. 8 be sure to use a new cotter pin and bend the ends over securely. Other- wise, the propeller could come off dur- ing operation an...

  • Page 101

    4-24 e 601021 q w emu00905 changing gear oil w 8 be sure the outboard is securely fas- tened to the transom or a stable stand. You could be severely injured if the out- board falls on you. 8 never get under the lower unit while it is tilted, even when the tilt-support lever is locked. Severe injury ...

  • Page 102

    4-25 e note: for disposal of used oil consult your yamaha dealer. 5) with the outboard motor in an verti- cal position, using a flexible or pres- surized filling device, inject the gear oil into the oil drain plug hole. 6) when the oil begins to flow out of the oil level plug hole, insert and tighte...

  • Page 103

    4-26 e 603023 902054 to clean the fuel tank 1) empty the fuel tank into an approved gasoline (petrol) container. 2) pour a small amount of suitable sol- vent in the tank. Reinstall the cap and shake the tank. Drain the solvent completely. To clean the fuel filter 1) remove the screws holding the fue...

  • Page 104

    4-27 e emu00404 checking battery (for electric start model) w battery electrolytic fluid is dangerous; it contains sulfuric acid and therefore is poi- sonous and highly caustic. Always follow these preventive mea- sures: 8 avoid bodily contact with electrolytic fluid as it can cause severe burns or ...

  • Page 105

    4-28 e c c 8 a poorly maintained battery will quick- ly deteriorate. 8 ordinary tap-water contains minerals harmful to a battery, and should not be used for topping-up. 1) check the electrolyte level at least once a month. Fill to the manufactur- er’s recommended level when neces- sary. Top up only ...

  • Page 106

    4-29 e emu01279 connecting the battery w mount the battery holder securely in a dry, well-ventilated, vibration-free loca- tion in the boat. Install a fully charged battery in the holder. C c 8 make sure the main switch (on applica- ble models) is “off” before working on the battery. 8 reversal of t...

  • Page 107

    4-30 e 102031 102025 emu00409 motor exterior emu00410 cleaning the outboard motor after use, wash the exterior of the out- board with fresh water. Flush the cooling system with fresh water. Note: refer to flushing cooling system instruc- tions in “transporting and storing outboard motor”. Checking p...

  • Page 108: -Memo-

    E -memo- 6l2-9-1h 4 4/20/01 1:49 pm page 32.

  • Page 109: Chapter 5

    Emn00010 chapter 5 trouble recovery troubleshooting ..............................5-1 temporary action in emergency ............................................5-5 impact damage.....................................5-5 starter will not operate ........................5-6 treatment of submerged motor ...

  • Page 110: Troubleshooting

    5-1 e emu01204¯ troubleshooting a problem in the fuel, compression, or ignition systems can cause poor starting, loss of power, or other problems. The troubleshooting chart describes basic checks and possi- ble remedies. (this chart covers all yamaha outboard motors. Therefore, some items may not ap...

  • Page 111

    5-2 e c. Engine idles irregularly or stalls. Trouble possible cause remedy 1. Spark plug(s) fouled or incorrect type. 2. Fuel system obstructed. 3. Fuel contaminated or stale. 4. Fuel filter clogged. 5. Failed ignition parts. 6. Warning system activated. 7. Spark plug gap incorrect. 8. Poor connecti...

  • Page 112

    5-3 e d. Warning buzzer sounds or indicator lamp lights. Trouble possible cause remedy 1. Cooling system clogged. 2. Engine oil level low. 3. Heat range of spark plug incorrect. 4. Specified engine oil not used. 5. Engine oil contaminated or deteriorated. 6. Oil filter clogged. 7. Oil feed/injection...

  • Page 113

    5-4 e trouble possible cause remedy 13. Poor connections or damaged ignition wiring. 14. Failed ignition parts. 15. Specified engine oil not used. 16. Thermostat faulty or clogged. 17. Air vent screw closed. 18. Fuel pump damaged. 19. Fuel joint connection incorrect. 20. Heat range of spark plug inc...

  • Page 114: Temporary Action In

    5-5 emn20010 temporary action in emergency emh80010 impact damage w the outboard motor can be seriously damaged by a collision while operating or trailering. Damage could make the out- board motor unsafe to operate. If the outboard motor hits any object in the water, follow the procedure below; 1) s...

  • Page 115

    5-6 emu00423 starter will not operate if the starter mechanism does not operate (engine cannot be cranked with the starter), the engine can be started with an emergency starter rope. W 8 use this procedure only in an emer- gency and only to return to port for repairs. 8 when the emergency starter ro...

  • Page 116

    5-7 emu00950 emergency starting engine 1) remove the top cowling. 2) remove the start-in-gear protection cable from the starter if equipped it. 3) remove the starter/flywheel cover after removing the bolt(s). 4) prepare the engine for starting. See “starting engine” for procedures. Be sure the engin...

  • Page 117

    5-8 emn50011 treatment of submerged motor if the outboard motor is submerged, immediately take it a yamaha dealer. Oth- erwise, some corrosion may begin almost immediately. If you cannot immediately take the outboard motor to a yamaha dealer, follow the procedure bellow for taking care to minimize e...

  • Page 118: -Memo-

    E -memo- 6l2-9-1h 5 4/20/01 1:48 pm page 10

  • Page 119: Chapter 6

    Emp00010 chapter 6 index index........................................................6-1 1 2 3 4 5 6 e 6l2-9-1h 6 4/20/01 1:48 pm page 1.

  • Page 120: Index

    6-1 e emp10010 index a adjusting idling speed ..........................4-16 adjusting trim angle..............................3-27 air vent screw...........................................2-3 b basic boating rules ..................................1-6 battery care......................................

  • Page 121

    6-2 e mounting height ......................................3-3 mounting the outboard motor ...............3-2 n neutral interlock trigger ..........................2-8 neutral throttle lever ...............................2-8 o oil level warning system.......................2-16 oil level warning/o...

  • Page 122: Canada

    Emu01599 important warranty information for u.S.A. And canada welcome to the yamaha family! Congratulations on the purchase of your new yamaha marine power. Yamaha is commit- ted to exceptional customer satisfaction, and we want your ownership experience to be a satisfying one. Please read the follo...

  • Page 123

    5. Your warranty applies specifically to repairs made in the country of purchase. If your u.S.-purchased yamaha needs warranty service while in canada, or your canadian pur- chased yamaha needs service while in the united states, yamaha will assist the local dealer whenever possible. However, some p...

  • Page 124

    Emu00912* yamaha motor corporation, u.S.A. Outboard motor two year limited warranty yamaha motor corporation, u.S.A. Is proud of its heritage and reputation for producing products with high standards of quality and workmanship. Product excellence provides the cornerstone for our commitment to custom...

  • Page 125

    Specific parts excluded from warranty. Parts replaced due to normal wear or routine maintenance such as oil, spark plugs, shear pins, propellers, hubs, fuel and oil filters, brushes for the starter motor and power tilt motor, water pump impellers, and anodes are not covered by warranty. Charges for ...

  • Page 126

    Customer service if your machine requires warranty service, you must take it to any authorized yamaha outboard dealer within the continental united states. Be sure to bring your warranty registration identification or other valid proof of the original date of purchase. If a question or problem arise...

  • Page 127

    Emu01178 important warranty information if you use your yamaha outside u.S.A. Or canada welcome to the yamaha family! Congratulations on the purchase of your new yamaha marine power. Yamaha is com- mitted to exceptional customer satisfaction, and we want your ownership experience to be a satisfying ...

  • Page 128

    6l2-9-1h 6 4/20/01 1:48 pm page 10

  • Page 129

    6l2-9-1h \ 01.4.20 3:05 pm y [ w 2 (2,1).

  • Page 130: Own

    25a/30a printed in japan april 2001—1.0 × 1 ! 6l2-28199-1h (25nmh/25jmh/30dmho/30deho/30deo) (e) printed on recycled paper own 6l2-9-1h \ 01.4.20 3:05 pm y [ w 1 (1,1).

  • Page 131

    25a/30a lit-18626-04-54 25a 30a owner’s manual u.S.A.Edition 6l2-9-1h \ 01.4.20 3:05 pm y [ w 1 (2,1).