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Yamaha 25B Owner's Manual

Summary of 25B

  • Page 1

    Owner’s manual e25b 25b 25x 30h 69r-28199-27-e0

  • Page 2

    Emu25051 read this owner’s manual carefully before operating or working on your outboard motor. Keep this manual onboard in a waterproof bag when boating. This manual should stay with the outboard motor if it is sold..

  • Page 3: Important Manual Information

    Important manual information emu25103 to the owner thank you for choosing a yamaha outboard motor. This owner’s manual contains infor- mation needed for proper operation, mainte- nance and care. A thorough understanding of these simple instructions will help you ob- tain maximum enjoyment from your ...

  • Page 4: Table of Contents

    Table of contents general information .......................... 1 identification numbers record .......... 1 outboard motor serial number .......... 1 key number....................................... 1 ec label........................................... 1 c-tick label ................................

  • Page 5: Table of Contents

    Table of contents filling fuel for portable tank ............. 22 gasoline and oil mixing (100:1) ...... 23 operating engine........................... 24 feeding fuel (portable tank) ............ 24 starting engine ................................ 25 warming up engine ....................... 30 cho...

  • Page 6: General Information

    1 general information emu25170 identification numbers record emu25183 outboard motor serial number the outboard motor serial number is stamped on the label attached to the port side of the clamp bracket. Record your outboard motor serial number in the spaces provided to assist you in ordering spare ...

  • Page 7: General Information

    General information 2 emu25213 c-tick label engines affixed with this label conform to certain portion(s) of the australian radio communications act. Emu25382 important labels emu25395 warning labels emu25401 label warning ewm01260 ● be sure shift control is in neutral before starting engine. (excep...

  • Page 8: General Information

    General information 3 starting device. ● the engine will not start unless the shift control is in neutral position. Emu25465 caution labels emu30480 label caution: ecm01450 use premix fuel only. Zmu04736.

  • Page 9: Safety Information

    4 safety information emu33620 safety information observe these precautions at all times. Emu33630 rotating parts hands, feet, hair, jewelry, clothing, pfd straps, etc. Can become entangled with inter- nal rotating parts of the engine, resulting in serious injury or death. Keep the top cowling in pla...

  • Page 10: Safety Information

    Safety information 5 emu33740 boating safety this section includes a few of the many im- portant safety precautions that you should follow when boating. Emu33710 alcohol and drugs never operate after drinking alcohol or tak- ing drugs. Intoxication is one of the most common factors contributing to b...

  • Page 11: Safety Information

    Safety information 6 emu33790 weather stay informed about the weather. Check weather forecasts before boating. Avoid boating in hazardous weather. Emu33880 passenger training make sure at least one other passenger is trained to operate the boat in the event of an emergency. Emu33890 boating safety p...

  • Page 12: Basic Requirements

    7 basic requirements emu25540 fueling instructions warning ewm00010 gasoline and its vapors are high- ly flammable and explosive! ● do not smoke when refueling, and keep away from sparks, flames, or other sources of ignition. ● stop engine before refueling. ● refuel in a well-ventilated area. Refuel...

  • Page 13: Basic Requirements

    Basic requirements 8 19. Warning ewm01570 ● improper mounting of the outboard mo- tor could result in hazardous condi- tions such as poor handling, loss of control, or fire hazards. ● because the motor is very heavy, spe- cial equipment and training is required to mount it safely. Emu33580 remote co...

  • Page 14: Basic Requirements

    Basic requirements 9 where a different propeller would be more appropriate. Your yamaha dealer can help you select the right propeller for your boating needs. Select a propeller that will allow the engine to reach the middle or upper half of the operating range at full throttle with the maximum boat...

  • Page 15: Basic Components

    10 basic components emu2579b main components note: * may not be exactly as shown; also may not be included as standard equipment on all mod- els. E25b, 25b, 25x, 30h emu25802 fuel tank if your model was equipped with a portable 9 8 7 6 3 4 5 2 1 19 18 17 11 12 13 14 11 19 18 17 15 16 14 15 16 20 21 ...

  • Page 16: Basic Components

    Basic components 11 fuel tank, its function is as follows. Warning ewm00020 the fuel tank supplied with this engine is its dedicated fuel reservoir and must not be used as a fuel storage container. Com- mercial users should conform to relevant licensing or approval authority regula- tions. Emu25830 ...

  • Page 17: Basic Components

    Basic components 12 emu26201 neutral interlock trigger to shift out of neutral, first pull the neutral in- terlock trigger up. Emu26211 neutral throttle lever to open the throttle without shifting into ei- ther forward or reverse, put the remote con- trol lever in the neutral position and lift the n...

  • Page 18: Basic Components

    Basic components 13 emu25922 gear shift lever pulling the gear shift lever towards you puts the engine in forward gear so that the boat moves ahead. Pushing the lever away from you puts the engine in reverse gear so that the boat moves astern. Emu25941 throttle grip the throttle grip is on the tille...

  • Page 19: Basic Components

    Basic components 14 there is too much resistance, it could be difficult to move the remote control lever or throttle grip, which could result in an accident. When constant speed is desired, tighten the adjuster to maintain the desired throttle set- ting. Emu25991 engine shut-off switch the clip must...

  • Page 20: Basic Components

    Basic components 15 emu26001 engine stop button to open the ignition circuit and stop the en- gine, push this button. Emu26011 choke knob for pull type to supply the engine with the rich fuel mix- ture required to start, pull out this knob. Emu26070 manual starter handle to start the engine, first g...

  • Page 21: Basic Components

    Basic components 16 set according to operator preference. An ad- justing screw or bolt is located on the swivel bracket. To increase resistance, turn the adjuster clockwise. To decrease resistance, turn the adjuster counterclockwise. Warning ewm00040 do not overtighten the friction adjuster. If ther...

  • Page 22: Basic Components

    Basic components 17 emu30530 tilt lock mechanism the tilt lock mechanism is used to prevent the outboard motor from lifting out of the wa- ter when in reverse gear. To lock it, set the tilt lock lever in the lock po- sition. To release, push the tilt lock lever in the release position. Emu26321 tilt...

  • Page 23: Basic Components

    Basic components 18 emu26410 2-pin connector ac 12 v-40/60/80w power is delivered through this connector. When using it, keep in mind the following points: ● use a genuine yamaha connector. ● use lighting equipment only. ● connect lighting equipment directly to the 2-pin connector. ● capacity of the...

  • Page 24: Operation

    19 operation emu26902 installation the information presented in this section is intended as reference only. It is not possible to provide complete instructions for every possible boat and motor combination. Prop- er mounting depends in part on experience and the specific boat and motor combination. ...

  • Page 25: Operation

    Operation 20 caution: ecm01630 ● during water testing, check the buoy- ancy of the boat, at rest, with its maxi- mum load. Check that the static water level on the exhaust housing is low enough to prevent water entry into the power head when water rises due to waves when the outboard is not run- nin...

  • Page 26: Operation

    Operation 21 if it accidentally falls off the transom. 3. Secure the clamp bracket to the transom using the bolts provided with the out- board (if packed). For details, consult your yamaha dealer. Warning ewm00650 avoid using bolts, nuts or washers other than those contained in the engine pack- agin...

  • Page 27: Operation

    Operation 22 3. Next two hours: accelerate at full throttle onto plane, then reduce engine speed to three-quar- ter throttle (approximately 4000 r/min). Vary engine speed occasionally. Run at full throttle for one minute, then allow about 10 minutes of operation at three- quarter throttle or less to...

  • Page 28: Operation

    Operation 23 sources of ignition. 1. Remove the fuel tank cap. 2. Fill the fuel tank carefully. 3. Close the cap securely after refueling. Wipe up any spilled fuel. Emu27405 gasoline and oil mixing (100:1) if equipped with a portable fuel tank 1. Pour oil into the portable fuel tank, and then add ga...

  • Page 29: Operation

    Operation 24 emu27450 operating engine emu27463 feeding fuel (portable tank) warning ewm00420 ● 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. ● when the air vent screw is lo...

  • Page 30: Operation

    Operation 25 emu27491 starting engine warning ewm01600 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 wa- ter near you. Emu27506 manual start models (tiller control) 1. Place the gear shift ...

  • Page 31: Operation

    Operation 26 4. Pull out / turn the choke knob fully. After the engine starts, replace / return the knob to the home position. Note: ● it is not necessary to use the choke when starting a warm engine. ● if the choke knob is left in the “ ” (start) position while the engine is running, the engine wil...

  • Page 32: Operation

    Operation 27 note: the start-in-gear protection device prevents the 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 arm or leg. Then install the clip on the other end of the cord into the engine shut-off switch. Warning ...

  • Page 33: Operation

    Operation 28 note: ● it is not necessary to use the choke when starting a warm engine. ● if the choke knob is left in the “ ” (start) position while the engine is running, the engine will run poorly or stall. 5. Pull the manual starter handle slowly un- til you feel resistance. Then give a strong pu...

  • Page 34: Operation

    Operation 29 the boat could slow rapidly. This could cause people and objects in the boat to be thrown forward. 3. Turn the main switch to “ ” (on). 4. Open the throttle slightly without shifting using the neutral throttle lever or free ac- celerator. You may need to change the throttle opening slig...

  • Page 35: Operation

    Operation 30 6. Turn the main switch to “ ” (start), and hold it for a maximum of 5 seconds. 7. Immediately after the engine starts, re- lease the main switch and allow it to re- turn to “ ” (on). Caution: ecm00191 ● never turn the main switch to “ ” (start) while the engine is running. ● do not kee...

  • Page 36: Operation

    Operation 31 engine and allow it to warm up. To shift out of neutral 1. Pull the neutral interlock trigger up (if equipped). 2. Move the remote control lever / gear shift lever firmly and crisply forward (for forward gear) or backward (for reverse gear) [about 35° (a detent can felt) for re- mote co...

  • Page 37: Operation

    Operation 32 2. After the engine is at idle speed in gear move the remote control lever / gear shift lever firmly and crisply into the neu- tral position. Emu31742 stopping boat warning ewm01510 ● do not use the reverse function to slow down or stop the boat as it could cause you to lose control, be...

  • Page 38: Operation

    Operation 33 2. After stopping the engine, disconnect the fuel line if there is a fuel joint on the outboard motor. 3. Tighten the air vent screw on the fuel tank cap (if equipped). 4. Remove the key if the boat will be left unattended. Note: the engine can also be stopped by pulling the cord and re...

  • Page 39: Operation

    Operation 34 emu27872 adjusting trim angle for manual tilt models there are 4 or 5 holes provided in the clamp bracket 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 brack- et. 3. Reposition the rod in the d...

  • Page 40: Operation

    Operation 35 the boat is up about 3 to 5 degrees. With the bow up, the boat may have a greater tenden- cy to steer to one side or the other. Compen- sate for this as you steer. The trim tab can also be adjusted to help offset this effect. When the bow of the boat is down, it is easier to accelerate ...

  • Page 41: Operation

    Operation 36 the engine will be tilted for more than a few minutes. Otherwise fuel may leak. Caution: ecm00241 ● before tilting the outboard motor, stop the engine by following the procedure on page 32. Never tilt the outboard mo- tor while the engine is running. Severe damage from overheating can r...

  • Page 42: Operation

    Operation 37 when trailering the boat. The outboard motor could shake loose from the tilt sup- port and fall. If the motor cannot be trail- ered in the normal running position, use an additional support device to secure it in the tilt position. For more detailed in- formation, see page 40. Emu28013 ...

  • Page 43: Operation

    Operation 38 2. Push the tilt lock lever down to the re- lease position. 3. Slightly tilt the outboard motor up and pull the shallow water lever toward the transom. 4. To return the outboard motor to the nor- mal position, place the gear shift lever in neutral, then slightly tilt the outboard motor ...

  • Page 44: Maintenance

    39 maintenance emu31480 specifications note: “(al)” stated in the specification data below represents the numerical value for the alumi- num propeller installed. Likewise, “(sus)” represents the value for stainless steel propeller installed and “(pl)” for plastic propeller installed. Emu28219 dimens...

  • Page 45: Maintenance

    Maintenance 40 30hmh br8hs-10 30hw br8hs-10 e25bmh br7hs-10 spark plug gap: 0.9–1.0 mm (0.035–0.039 in) control system: 25bmh tiller 25xmh tiller 30hmh tiller 30hw remote control e25bmh tiller starting system: 25bmh manual 25xmh manual 30hmh manual 30hw manual and electric e25bmh manual starting car...

  • Page 46: Maintenance

    Maintenance 41 transporting and storing the outboard motor, close the air vent screw and fuel cock to prevent fuel from leaking. ● use care when transporting fuel tank, whether in a boat or car. ● do not fill fuel container to maximum capacity. Gasoline will expand consid- erably as it warms up and ...

  • Page 47: Maintenance

    Maintenance 42 lowing procedures. Caution: ecm01411 ● do not place the outboard motor on its side before the cooling water has drained from it completely, otherwise water may enter the cylinder through the exhaust port and cause engine trou- ble. ● store the outboard motor in a dry, well- ventilated...

  • Page 48: Maintenance

    Maintenance 43 cessively and almost stall. 8. Remove the outboard motor from the test tank. 9. Install the silencer cover/cap of fogging hole and top cowling. 10. If the “fogging oil” is not available, run the engine at a fast idle until the fuel sys- tem becomes empty and the engine stops. 11. Drai...

  • Page 49: Maintenance

    Maintenance 44 procedure 1. Disconnect and remove the battery from the boat. Always disconnect the black negative cable first to prevent the risk of shorting. 2. Clean the battery casing and terminals. Fill each cell to the upper level with dis- tilled water. 3. Store the battery on a level surface ...

  • Page 50: Maintenance

    Maintenance 45 emu28522 maintenance chart frequency of maintenance operations may be adjusted according to the operating condi- tions, but the following table gives general guidelines. Refer to the sections in this chapter for explanations of each owner-specific action. Note: when operating in salt ...

  • Page 51: Maintenance

    Maintenance 46 emu28874 maintenance chart (additional) spark plug(s) cleaning / adjustment / replacement item actions every 500 hours (2.5 years) 1000 hours (5 years) exhaust guide, exhaust manifold inspection / replace- ment item actions initial every 10 hours (1 month) 50 hours (3 months) 100 hour...

  • Page 52: Maintenance

    Maintenance 47 emu28941 greasing yamaha grease a (water resistant grease) yamaha grease d (corrosion resistant grease; for propeller shaft) e25b, 25b, 25x, 30h emu28953 cleaning and adjusting spark plug warning ewm00560 when removing or installing a spark plug, be careful not to damage the insulator...

  • Page 53: Maintenance

    Maintenance 48 fire. Warning ewm01550 the engine will still be very hot when it has just been turned off. Take extremely care so that neither you nor anyone else gets burnt. To avoid burns, work on the engine when it has cooled down. The spark plug is an important engine com- ponent and is easy to i...

  • Page 54: Maintenance

    Maintenance 49 sources of ignition. Warning ewm00910 leaking fuel can result in fire or explo- sion. ● check for fuel leakage regularly. ● if any fuel leakage is found, the fuel system must be repaired by a qualified mechanic. Improper repairs can make the outboard unsafe to operate. Check the fuel ...

  • Page 55: Maintenance

    Maintenance 50 solvent. Allow it to dry. Inspect the filter element and o-ring to make sure they are in good condition. Replace them if necessary. If any water is found in the fuel, the yamaha portable fuel tank or other fuel tanks should be checked and cleaned. 4. Reinstall the filter element in th...

  • Page 56: Maintenance

    Maintenance 51 emu29120 exhaust leakage start the engine and check that no exhaust leaks from the joints between the exhaust cover, cylinder head, and body cylinder. Emu29130 water leakage start the engine and check that no water leaks from the joints between the exhaust cover, cylinder head, and bo...

  • Page 57: Maintenance

    Maintenance 52 age. Emu30661 removing propeller emu29195 spline models 1. Straighten the cotter pin and pull it out using a pair of pliers. 2. Remove the propeller nut, washer, and spacer (if equipped). 3. Remove the propeller and thrust wash- er. Emu30671 installing propeller emu29231 spline models...

  • Page 58: Maintenance

    Maintenance 53 1. Tilt the outboard motor so that the gear oil drain screw is at the lowest point pos- sible. 2. Place a suitable container under the gear case. 3. Remove the gear oil drain screw and gasket. Note: ● if a magnetic gear oil drain screw is equipped, remove all metal particles from the ...

  • Page 59: Maintenance

    Maintenance 54 an area with good ventilation. ● wipe up any spilled fuel immediately. ● reassemble the fuel tank carefully. Im- proper assembly can result in a fuel leak, which could result in a fire or ex- plosion hazard. ● dispose of old gasoline according to lo- cal regulations. 1. Empty the fuel...

  • Page 60: Maintenance

    Maintenance 55 and get immediate medical attention. Antidote (internal): ● drink large quantities of water or milk followed by milk of magnesia, beaten egg, or vegetable oil. Get immediate medical attention. Batteries also generate explosive hydro- gen gas; therefore, you should always follow these ...

  • Page 61: Maintenance

    Maintenance 56 when installing the battery and discon- nect the black battery cable first when removing it. ● the electrical contacts of the battery and cables must be clean and properly connected, or the battery will not start the engine. Connect the red battery cable to the posi- tive (+) terminal...

  • Page 62: Trouble Recovery

    57 trouble recovery emu29425 troubleshooting a problem in the fuel, compression, or igni- tion systems can cause poor starting, loss of power, or other problems. This section de- scribes basic checks and possible remedies, and covers all yamaha outboard motors. Therefore some items may not apply to ...

  • Page 63: Trouble Recovery

    Trouble recovery 58 a. Check for pinched or kinked fuel line or other obstructions in fuel system. Q. Is fuel contaminated or stale? A. Fill tank with clean, fresh fuel. Q. Is fuel filter clogged? A. Clean or replace filter. Q. Have ignition parts failed? A. Have serviced by a yamaha dealer. Q. Has ...

  • Page 64: Trouble Recovery

    Trouble recovery 59 q. Is load on boat improperly distributed? A. Distribute load to place boat on an even plane. 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? ...

  • Page 65: Trouble Recovery

    Trouble recovery 60 q. Is fuel joint connection incorrect? 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...

  • Page 66: Trouble Recovery

    Trouble recovery 61 note: consult your yamaha dealer if the new fuse immediately blows again. Emu29533 starter will not operate if 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. Warning ewm01022 ● ...

  • Page 67: Trouble Recovery

    Trouble recovery 62 3. Remove the starter/flywheel cover after removing the bolt(s). 4. Prepare the engine for starting. For fur- ther information, see page 25. Be sure the engine is in neutral and that the clip is attached to the engine shut-off switch. The main switch must be “ ” (on), if equipped...

  • Page 68: Trouble Recovery

    Trouble recovery 63 2. Remove the spark plugs and face the spark plug holes downward to allow any water, mud, or contaminants to drain. 3. Drain the fuel from the carburetor, fuel filter, and fuel line. 4. Feed fogging oil or engine oil through the carburetor(s) and spark plug holes while cranking w...

  • Page 70

    Yamaha motor co., ltd. Printed on recycled paper printed in japan april 2007–0.5 × 1 !.