8-117
EBU00440
Troubleshooting chart
Starting problems or poor engine performance
Check fuel flow
1. Fuel
Check if there is
fuel in the fuel
tank
2. Compression
Kick the kick starter
to see if there is
compression
3. Ignition
Remove plugs and
check electrodes
WetWipe clean with
dry cloth
DryAttach plug cap and
ground to chassisKick the kick
starter stronglySpark weak
Spark goodIgnition system normal
No spark
Ask a Yamaha dealer to inspect
Adjust plug gap or
replace plug(s)
There is compressonCompression normal
Ask a Yamaha dealer to inspectNo compression
There is fuelTurn the fuel
cock to “OFF”
Remove the
fuel pipeNo fuelFuel cock clogged
Some fuelTurn the fuel
cock to “RES”Restart engine
No fuelSupply fuel
Clean fuel cock
8-118
Engine overheating
Wait until the
engine has cooled.Check the coolant level in the
reservoir tank 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
repair the cooling system.
NOTE:
If it is difficult to get recommended coolant, tap water can be temporarily used, provided that it is
changed to the recommended coolant as soon as possible.
w
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.