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Yamaha 20D Owner's Manual

Summary of 20D

  • Page 1

    Owner’s manual 20d 25n 6l3-28199-78-e0

  • Page 2

    Emu25050 read this owner’s manual carefully before operating your outboard motor..

  • Page 3: Important Manual Information

    Important manual information emu25101 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 safety information ..........................

  • Page 5: Table of Contents

    Table of contents tilting up and down ....................... 35 procedure for tilting up .................... 35 procedure for tilting down (manual tilt models) .................................... 36 cruising in shallow water .............. 36 cruising in shallow water (manual tilt models) ..........

  • Page 6: General Information

    1 general information emu25170 identification numbers record emu25182 outboard motor serial number the outboard motor serial number is stamped on the label attached to the port side of the clamp bracket or the upper part of the swivel bracket. Record your outboard motor serial number in the spaces p...

  • Page 7: General Information

    General information 2 emu25371 safety information ● before mounting or operating the outboard motor, read this entire manual. Reading it should give you an understanding of the motor and its operation. ● before operating the boat, read any own- er’s or operator’s manuals supplied with it and all lab...

  • Page 8: General Information

    General information 3 watch for obstacles and other traffic. ● always watch carefully for swimmers dur- ing the engine operation. ● stay away from swimming areas. ● when a swimmer is in the water near you shift into neutral and shut off the engine. ● do not illegally discard empty containers used to...

  • Page 9: General Information

    General information 4 portable fuel tanks off the boat. ● take care not to spill gasoline. If gaso- line spills, wipe it up immediately with dry rags. ● do not overfill the fuel tank. ● tighten the filler cap securely after re- fueling. ● if you should swallow some gasoline, inhale a lot of gasoline...

  • Page 10: General Information

    General information 5 emu25742 propeller selection the performance of your outboard motor will be critically affected by your choice of propel- ler, as an incorrect choice could adversely affect performance and could also seriously damage the motor. Engine speed depends on the propeller size and boa...

  • Page 11: General Information

    General information 6 1. Start-in-gear protection label zmu01713 1.

  • Page 12: Basic Components

    7 basic components emu25795 main components note: * may not be exactly as shown; also may not be included as standard equipment on all mod- els. 20d, 25n emu25802 fuel tank if your model was equipped with a portable fuel tank, its function is as follows. Warning ewm00020 the fuel tank supplied with ...

  • Page 13: Basic Components

    Basic components 8 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 fuel joint this joint is used to connect the fuel line. Emu25841 fuel gauge this gauge is located on...

  • Page 14: Basic Components

    Basic components 9 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 ne...

  • Page 15: Basic Components

    Basic components 10 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 16: Basic Components

    Basic components 11 there is too much resistance, it could be difficult to move throttle lever or grip, which could result in an accident. When constant speed is desired, tighten the adjuster to maintain the desired throttle set- ting. Emu25990 engine stop lanyard switch the lock plate must be attac...

  • Page 17: Basic Components

    Basic components 12 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 18: Basic Components

    Basic components 13 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 19: Basic Components

    Basic components 14 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. Emu26330 tilt...

  • Page 20: Basic Components

    Basic components 15 ● use a genuine yamaha connector. ● use lighting equipment only. ● connect lighting equipment directly to the 2-pin connector. ● capacity of the lighting equipment must be more than 12 v-40/60/80w; otherwise the bulb could burn out. ● when the connector is not in use, place the c...

  • Page 21: Basic Components

    Basic components 16 ● the buzzer will sound (if equipped on the tiller handle, remote control box, or main switch panel). If the warning system has activated, stop the engine and check the cooling water inlet for clogging. Emu26845 oil level warning and oil filter clogging warning oil injection mode...

  • Page 22: Basic Components

    Basic components 17 1. Oil filter 1 zmu03707.

  • Page 23: Operation

    18 operation emu26901 installation caution: ecm00110 incorrect engine height or obstructions to smooth water flow (such as the design or condition of the boat, or accessories such as transom ladders or depth finder transducers) can create airborne water spray while the boat is cruising. Severe engin...

  • Page 24: Operation

    Operation 19 motor greatly affects the water resistance. If the mounting height is too high, cavitation tends to occur, thus reducing the propulsion; and if the propeller tips cut the air, the engine speed will rise abnormally and cause the en- gine to overheat. If the mounting height is too low, th...

  • Page 25: Operation

    Operation 20 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- aging. If used, they must be of at least the same quality of material and strength and must be tightened securely. After tighten...

  • Page 26: Operation

    Operation 21 cool. 4. Third through tenth hours: avoid operating at full throttle for more than 5 minutes at a time. Let the engine cool between full-throttle runs. Vary en- gine speed occasionally. 5. After the first 10 hours: operate the engine normally. Use only straight gasoline in the fuel tank...

  • Page 27: Operation

    Operation 22 caution: ecm01260 be sure to take the above steps when op- erating the engine after a long period of storage. Otherwise engine seizure could occur. Emu27233 filling fuel and engine oil emu27242 filling fuel for portable tank warning ewm00060 gasoline and its vapors are highly flam- mabl...

  • Page 28: Operation

    Operation 23 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. 2. Oil tank filler cap.

  • Page 29: Operation

    Operation 24 emu27321 oil level indicator operation the various functions of the oil level system are as follows: emu27332 emu27450 operating engine emu27461 feeding fuel (portable tank) warning ewm00420 ● before starting the engine, make sure that the boat is tightly moored and that you can steer c...

  • Page 30: Operation

    Operation 25 3. If a steering friction adjuster is provided on your outboard motor, securely attach the fuel line to the fuel line clamp. Note: during engine operation place the tank hori- zontally, otherwise fuel cannot be drawn from the fuel tank. 4. Squeeze the primer pump with the outlet end up ...

  • Page 31: Operation

    Operation 26 3. Place the throttle grip in the “ ” (start) position. 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 “ ” (sta...

  • Page 32: Operation

    Operation 27 amount and try to start the engine again. If the engine still fails to start, see page 56. Emu27632 manual start models (remote control) 1. Place the remote control lever in neutral. Note: the start-in-gear protection device prevents the engine from starting except when in neu- tral. 2....

  • 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 power, 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 openi...

  • 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 emu27763 forward (tiller handle and remote control models) tiller control models 1. Place the throttle grip in the fully closed position. 2. Move the gear shift lever quickly and firmly from neutral to forward. Remote control models 1. Pull up the neutral interlock trigger (if equipped)...

  • Page 37: Operation

    Operation 32 3. Move the gear shift lever quickly and firmly from neutral to reverse. Remote control models 1. Check that the tilt lock lever is in the lock position. 2. Pull up the neutral interlock trigger (if equipped) and move the remote control lever quickly and firmly from neutral to reverse. ...

  • Page 38: Operation

    Operation 33 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 lanyard and removing the lock plate from the engine ...

  • Page 39: Operation

    Operation 34 2. Remove the trim rod from the clamp bracket while slightly tilting the outboard motor up. 3. Reposition the rod in the desired hole. To raise the bow (“trim-out”), move the rod away from the transom. To lower the bow (“trim-in”), move the rod to- ward the transom. Make test runs with ...

  • Page 40: Operation

    Operation 35 bow down too much trim-in causes the boat to “plow” through the water, decreasing fuel economy and making it hard to increase speed. Oper- ating with excessive trim-in at higher speeds also makes the boat unstable. Resistance at the bow is greatly increased, heightening the danger of “b...

  • Page 41: Operation

    Operation 36 2. Disconnect the fuel line if a fuel joint is provided on the outboard motor. 3. Place the tilt lock lever in the release po- sition. 4. Hold the rear of the top cowling with one hand, tilt the engine up, and turn the tilt support lever to the lock position and support the engine. Emu2...

  • Page 42: Operation

    Operation 37 speed when using the shallow water cruising system. The tilt lock mecha- nism does not work while the shallow water cruising system is being used. Hitting an underwater obstacle could cause the outboard motor to lift out of the water, resulting in loss of control. ● do not rotate the ou...

  • Page 43: Operation

    Operation 38 4. Slightly tilt the outboard motor up. The tilt support bar will lock automatically, supporting the outboard motor in a par- tially raised position. Note: this outboard motor has 2 positions for shal- low water cruising. 5. To return the outboard motor to the nor- mal running position,...

  • Page 44: Maintenance

    39 maintenance emu28217 specifications dimension: overall length: 20dmho 936 mm (36.9 in) 20dwo 615 mm (24.2 in) 25nmho 936 mm (36.9 in) overall width: 20dmho 358 mm (14.1 in) 20dwo 304 mm (12.0 in) 25nmho 358 mm (14.1 in) overall height s: 1068 mm (42.0 in) overall height l: 1195 mm (47.0 in) trans...

  • Page 45: Maintenance

    Maintenance 40 regular unleaded gasoline min. Research octane: 90 fuel tank capacity: 25 l (6.60 us gal) (5.50 imp.Gal) recommended engine oil: yamalube 2-stroke outboard motor oil lubrication: oil injection engine oil tank capacity: 0.7 l (0.74 us qt) (0.62 imp.Qt) recommended gear oil: hypoid gear...

  • Page 46: Maintenance

    Maintenance 41 note: place a towel or something similar under the outboard motor to protect it from damage. Emu30272 storing outboard motor when storing your yamaha outboard motor for prolonged periods of time (2 months or longer), several important procedures must be performed to prevent excessive ...

  • Page 47: Maintenance

    Maintenance 42 mandatory to prevent excessive engine damage due to rust. Perform the flush- ing and fogging at the same time. Warning ewm00090 ● do not touch or remove electrical parts when starting or during operation. ● keep hands, hair, and clothes away from the flywheel and other rotating parts ...

  • Page 48: Maintenance

    Maintenance 43 follow these preventive measures: ● charge batteries in a well-ventilated ar- ea. ● keep batteries away from fire, sparks, or open flames (for example: welding equipment, lighted cigarettes, and so on.) ● do not smoke when charging or han- dling batteries. Keep batteries and electroly...

  • Page 49: Maintenance

    Maintenance 44 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 50: Maintenance

    Maintenance 45 spark plug(s) cleaning / adjustment / replacement item actions initial every 10 hours (1 month) 50 hours (3 months) 100 hours (6 months) 200 hours (1 year).

  • Page 51: Maintenance

    Maintenance 46 emu28940 greasing yamaha grease a (water resistant grease) yamaha grease d (corrosion resistant grease; for propeller shaft) 20d, 25n emu28952 cleaning and adjusting spark plug warning ewm00560 when removing or installing a spark plug, be careful not to damage the insulator. A damaged...

  • Page 52: Maintenance

    Maintenance 47 of the spark plug can indicate something about the condition of the engine. For exam- ple, if the center electrode porcelain is very white, this could indicate an intake air leak or carburetion problem in that cylinder. Do not attempt to diagnose any problems yourself. Instead, take t...

  • Page 53: Maintenance

    Maintenance 48 checkpoints ● fuel system parts leakage ● fuel line joint leakage ● fuel line cracks or other damage ● fuel connector leakage emu28980 inspecting fuel filter warning ewm00310 gasoline is highly flammable, and its va- pors are flammable and explosive. ● if you have any question about p...

  • Page 54: Maintenance

    Maintenance 49 4. Reinstall the filter element in the cup. Make sure the o-ring is in position in the cup. Firmly screw the cup onto the filter housing. 5. Attach the filter assembly to the bracket so that the fuel hoses are attached to the filter assembly. 6. Run the engine and check the filter and...

  • Page 55: Maintenance

    Maintenance 50 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 body cylinder. Emu29171 checking propeller warning ewm00321 you could be seriously injured if the en- gine accid...

  • Page 56: Maintenance

    Maintenance 51 emu30660 removing the propeller emu29194 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. Emu30670 installing the propeller emu29231 spline mod...

  • Page 57: Maintenance

    Maintenance 52 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. Note: if the magnetic gear oil drain screw equipped: remove all metal particles from the screw before installing it. 4. Remove the oil level plug t...

  • Page 58: Maintenance

    Maintenance 53 plosion hazard. ● dispose of old gasoline according to lo- cal regulations. 1. Empty the fuel tank into an approved container. 2. Pour a small amount of suitable solvent into the tank. Install the cap and shake the tank. Drain the solvent completely. 3. Remove the screws holding the f...

  • Page 59: Maintenance

    Maintenance 54 medical attention. Batteries also generate explosive hydro- gen gas; therefore, you should always follow these preventive measures: ● charge batteries in a well-ventilated ar- ea. ● keep batteries away from fire, sparks, or open flames (for example: welding equipment, lighted cigarett...

  • Page 60: Maintenance

    Maintenance 55 emu29370 disconnecting the battery disconnect the black cable from the neg- ative (-) terminal first. Then disconnect the red cable from the positive (+) terminal. Emu29390 checking top cowling check the fitting of the top cowling by push- ing it with both hands. If it is loose have i...

  • Page 61: Trouble Recovery

    56 trouble recovery emu29424 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 62: Trouble Recovery

    Trouble recovery 57 q. Is fuel system obstructed? 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 servic...

  • Page 63: Trouble Recovery

    Trouble recovery 58 a. Have serviced by a yamaha dealer. 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 ...

  • Page 64: Trouble Recovery

    Trouble recovery 59 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 65: Trouble Recovery

    Trouble recovery 60 note: consult your yamaha dealer if the new fuse immediately blows again. Emu29531 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 ewm01020 ● ...

  • Page 66: Trouble Recovery

    Trouble recovery 61 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 en- gine stop switch lanyard lock plate is at- tached to the engine stop switch. The main swi...

  • Page 67: Trouble Recovery

    Trouble recovery 62 and start the engine. Repeat if neces- sary. Emu29760 treatment of submerged motor if the outboard motor is submerged, immedi- ately take it to a yamaha dealer. Otherwise some corrosion may begin almost immedi- ately. If you cannot immediately take the outboard motor to a yamaha ...

  • Page 68

    Yamaha motor co., ltd. Printed on recycled paper printed in japan april 2005–0.2 × 1 !.