2004 YAMAHA YFM660R check engine

8-43
CAUTION:_ Hard water or salt water is harmful to the en-
gine. You may use soft water if you cannot get
distilled water. _12. Install the radiator cap and the coolant reser-
voir cap.
13. Start the engine and let it idle for several min-
utes. Stop the engine, and then check the
coolant level in the radiator. If it is low, add
more coolant until it reaches the top of the ra-
diator.
14. Check the coolant level in the reservoir. If it is
low, add coolant to the maximum level mark.
15. Start the engine and then check for coolant
leakage.NOTE:_ If any leakage is found, have a Yamaha dealer
check the cooling system. _16. Install the panel.
U5LP63.book Page 43 Monday, March 10, 2003 2:06 PM

8-49 1. Check hose
1. Flexible de contrôle
1. Manguito de comprobación
1. Air filter case cover 2. Holder (× 6)
1. Couvercle du boîtier de filtre à air 2. Support (× 6)
1. Tapa de la caja del filtro 2. Soporte (× 6)
EBU01212
Air filter element cleaningNOTE:_ There is a check hose at the bottom of the air filter
case. If dust or water collects in this hose, empty
the hose and clean the air filter element and air fil-
ter case. _1. Remove the seat. (See page 4-33 for seat re-
moval and installation procedures.)
2. Remove the air filter case cover by unhook-
ing the holders.
3. Remove the air filter element.
4. Remove the air filter element from its frame.
5. Wash the air filter element gently but thor-
oughly in solvent.
WARNING
_ Always use parts cleaning solvent to clean the
air filter element. Never use low flash point sol-
vents or gasoline to clean the air filter element
because the engine could catch fire or ex-
plode. _
U5LP63.book Page 49 Monday, March 10, 2003 2:06 PM

8-53 1. Hose
1. Flexible
1. Manguera
11. Install the air filter case cover and be sure to
connect the hose.
12. Install the seat.NOTE:_ The air filter element should be cleaned every 20–
40 hours. It should be cleaned and lubricated more
often if the machine is operated in extremely dusty
areas. Each time air filter element maintenance is
performed, check the air inlet to the air filter case
for obstructions. Check the air filter element rubber
joint to the carburetor and manifold fittings for an
airtight seal. Tighten all fittings securely to avoid
the possibility of unfiltered air entering the engine. _CAUTION:_ Never operate the engine with the air filter ele-
ment removed. This will allow unfiltered air to
enter, causing rapid engine wear and possible
engine damage. Additionally, operation with-
out the air filter element will affect carburetor
jetting with subsequent poor performance and
possible engine overheating. _
U5LP63.book Page 53 Monday, March 10, 2003 2:06 PM

8-125
EBU00724
Troubleshooting chart
Starting problems or poor engine performance1. Fuel
Check if there is fuel
in the fuel tank.There is fuel.Turn the fuel cock
lever to “OFF”.No fuel.Fuel cock is
clogged.
Clean the
fuel cock. Some fuel.Turn the fuel cock
lever to “RES”.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 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.Check the
fuel flow.
Turn the fuel cock
lever to “ON”.
Remove the fuel hose
from the fuel cock.
U5LP63.book Page 125 Monday, March 10, 2003 2:06 PM

8-126
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
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/or repair the cooling system.
U5LP63.book Page 126 Monday, March 10, 2003 2:06 PM