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EVU01530
Troubleshooting
Although Yamaha vehicles receive a rigid inspec-
tion before shipment from the factory, trouble may
occur during operation. Any problem in the fuel,
compression, or ignition systems can cause poor
starting and loss of power. The troubleshooting
chart describes a quick, easy procedure for mak-
ing checks. If your vehicle requires any repair, take
it to a Yamaha dealer.
The skilled technicians at a Yamaha dealership
have the tools, experience, and know-how to prop-
erly service your vehicle. Use only genuine
Yamaha parts on your vehicle. Imitation parts may
look like Yamaha parts, but they are often inferior.
Consequently, they have a shorter service life and
can lead to expensive repair bills.
WARNING
Do not smoke when checking the fuel system.
Fuel can ignite or explode, causing severe in-
jury or property damage. Make sure there are
no open flames or sparks in the area, including
pilot lights from water heaters or furnaces.
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8-135
EVU01540
Troubleshooting charts
Starting problems or poor engine performance1. Fuel
Check if there is fuel
in the fuel tank.There is fuel.
No fuel.Fuel pump is
clogged.
Restart the engine.
No fuel.Supply fuel.
2. Compression
Use the electric
starter to see if
there is compression.There is compression.
Compression normal.
No compression.Ask a Yamaha dealer to
inspect.
3. Ignition
Remove the
spark plug and
check the electrodes.WetWipe clean with dry cloth.
DryAttach spark plug cap and
ground to chassis.Use the
electric starter.Spark is good.Ignition system is
normal.
Spark is weak.
Adjust the spark plug gap
or replace the spark plug. No spark.
Ask a Yamaha dealer to
inspect. 4. Battery
Use the electric starter.Engine turns over
quickly.Battery is good.
Engine turns over
slowly.Check the connections,
recharge.Check the
fuel flow.
Remove the fuel hose
from the fuel pump.
Ask a Yamaha dealer to
inspect.
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8-136
Engine overheatingNOTE:_ If it is difficult to get the recommended coolant, tap water can be temporarily used, provided that it is
changed to the recommended coolant as soon as possible. _
WARNING
Wait for the engine and radiator to cool before removing the radiator cap. You could be burned by
hot fluid and steam blown out under pressure. Always put a thick rag over the cap when opening.
Allow any remaining pressure to escape before completely removing the cap.Wait until the
engine has cooled.
Check the coolant level in the
coolant reserver and/or radiator.
Level is OK.Level is low, check the
cooling system for leakage.
No
leakage.Leakage.
Ask a Yamaha dealer to inspect
and repair the cooling system.Add coolant. (See NOTE.)
Restart the engine. If the engine overheats again, ask a
Yamaha dealer to inspect and/or repair the cooling system.
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9-5
7. Automotive type wax may be applied to all
painted and chrome plated surfaces. Avoid
combination cleaner-waxes. Many contain
abrasives which may scratch the paint or pro-
tective finish. When finished, start the engine
and let it idle for several minutes.
WARNING
Wet brakes may have reduced stopping ability,
increasing the chance of an accident. Test the
brakes after washing. Apply the brakes several
times at slow speeds to let friction dry out the
linings.
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10-2
10
Compression ratio 9.10 :1
Starting system Electric starter
Lubrication system Wet sump
Engine oil:
Type
Recommended engine oil classification API Service SE, SF, SG type or higherModel YXR66FAV
-20˚ -10˚ 0˚
10˚20˚ 30˚40˚50˚C
10W/30
15W/4020W/4020W/50
10W/40
5W/30
CAUTION:
In order to prevent clutch slippage (since the en-
gine oil also lubricates the clutch), do not mix any
chemical additives. Do not use oils with a diesel
specification of “CD” or oils of a higher quality
than specified. In addition, do not use oils labeled
“ENERGY CONSERVING II” or higher.
EE.book Page 2 Monday, July 11, 2005 2:32 PM