check engine YAMAHA YFZ450 2006 User Guide

8-25
EBU13932
Engine oil and oil filter element
The engine oil level should be checked before
each ride. In addition, the oil must be changed
and the oil filter element replaced at the intervals
specified in the periodic maintenance and lubri-
cation chart.
To check the engine oil level
1. Place the ATV on a level surface.
2. Start the engine, warm it up until the
engine oil has reached a normal tempera-
ture of 40 ° C, let it continue to idle for ten
seconds or more, and then turn the engine
off.
NOTE:
To achieve the proper engine oil temperature for
an accurate oil level reading, the engine must
have first completely cooled down, and then
warmed up again for several minutes to normal
operating temperature.
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8-27
3. Remove the engine oil tank filler cap, wipe
the dipstick clean with a clean rag, insert it
back into the filler hole (without screwing it
in), and then remove it again to check the
oil level.
NOTE:
The engine oil should be between the minimum
and maximum level marks.
4. If the engine oil is below the minimum level
mark, add sufficient oil of the recommend-
ed type through the engine oil tank filler
hole to raise it to the correct level.
NOTE:
When adding oil, be careful not to overfill the
engine oil tank; the oil level rises faster starting
from the half-level-portion on the dipstick.
5. Insert the dipstick into the engine oil tank
filler hole, and then tighten the engine oil
tank filler cap.
1. Engine oil tank 2. Engine oil tank filler cap
3. Dipstick 4. Maximum level mark
5. Minimum level mark 6. Engine oil filler cap
1. Réservoir d’huile de moteur
2. Bouchon de remplissage de l’huile de moteur
3. Jauge
4. Repère de niveau maximum
5. Repère de niveau minimum
6. Bouchon de remplissage d’huile de moteur
1. Depósito de aceite de motor
2. Tapa de relleno del depósito de aceite de motor
3. Varilla de medición
4. Marca de nivel máximo
5. Marca de nivel mínimo
6. Tapa del filtro de aceite de motor
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8-31
4. Remove the engine oil filler cap and the
crankcase engine oil drain bolt.
5. Remove the engine oil tank filler cap and
the engine oil tank drain bolt.
6. Check the washers for damage, and
replace if necessary.
1. Crankcase engine oil drain bolt1. Boulon de vidange d’huile du carter1. Perno de drenaje de aceite de motor del cárter
1. Engine oil tank drain bolt
1. Boulon de vidange du réservoir d’huile1. Perno de drenaje del depósito aceite de motor
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8-39
cC
8In order to prevent clutch slippage (since
the engine 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.
8Make sure that no foreign material enters
the crankcase.
14. Start the engine, and then let it idle for sev-
eral minutes while checking it for oil leak-
age. If oil is leaking, immediately turn the
engine off and check for the cause.
15. Turn the engine off, and then check the oil
level and correct it if necessary.
16. Install the engine guard by installing the
bolts, and then tighten them to the speci-
fied torque.
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8-43
EBU10151
Cooling system
1. Check the coolant level in the coolant
reservoir when the engine is cold as the
coolant level will vary with engine tempera-
ture.
NOTE:
The coolant should be between the minimum
and maximum level marks.
2. If the coolant is at or below the minimum
level mark, remove the coolant reservoir
cap, and then add coolant or distilled water
to raise it to the specified level.
cC
Hard water or salt water is harmful to the
engine. You may use soft water if you can’t
get distilled water.
Coolant reservoir capacity
(up to the maximum level mark):
0.25 L
1. Maximum level mark 2. Minimum level mark
3. Coolant reservoir 4. Coolant reservoir cap
1. Repère maximum 2. Repère minimum
3. Vase d’expansion
4. Bouchon du vase d’expansion
1. Marca de máximo 2. Marca de mínimo
3. Depósito de refrigerante
4. Tapa del depósito de refrigerante
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8-53
cC
Hard water or salt water is harmful to the
engine. You may use soft water if you cannot
get distilled water.
12. Install the radiator cap and the coolant
reservoir cap.
13. Start the engine and let it idle for several
minutes. 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 radiator.
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.
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8-73
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 ele-
ment maintenance is performed, check the air
inlet to the air filter case for obstructions. Check
the air intake duct between the air filter case and
the carburetor and the manifold fittings for an
airtight seal. Tighten all fittings securely to avoid
the possibility of unfiltered air entering the
engine.
cC
Never operate the engine with the air filter
element removed. This will allow unfiltered
air to enter the engine, causing rapid engine
wear and possible engine damage.
Additionally, operation without the air filter
element will affect carburetor jetting with
subsequent poor performance and possible
engine overheating.
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8-77
EBU13970
Idle speed adjustment
A special tester is needed to check the engine
r/min on this model.
Therefore, take the ATV to a Yamaha dealer to
have the idle speed adjusted.
EBU03030
Valve clearance adjustment
The correct valve clearance changes with use,
resulting in improper fuel/air supply or engine
noise. To prevent this, the valve clearance must
be adjusted regularly. This adjustment however,
should be left to a professional Yamaha service
technician.Specified idle speed:
1,750–1,850 r/min
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8-149
EBU07240
Troubleshooting chart
Starting problems or poor
engine performance
2. Compression
Use the electric
starter to see if there
is compression.
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 weak.
Spark good.Ignition system normal.
No spark.
Ask a Yamaha dealer to inspect.
Adjust the spark plug gap
or replace the spark plug.
There is compresson.Compression normal.
Ask a Yamaha dealer to inspect.No compression.
4. Battery
Use the electric
starter
Engine turns over
quickly.Battery is good.
Check the connections, and charge the battery if necessary.Engine turns over
slowly
Check the fuel
flow.
1. Fuel
Check if there is
fuel in the fuel
tank.
There is fuel.Turn the fuel
cock to “OFF”.
Remove the
fuel hose from
the fuel cock.Turn the fuel cock
lever to “ON”.No fuel.Fuel cock clogged.
Some fuel.Turn the fuel cock
lever to “RES”.Restart the engine.
No fuel.Supply fuel.
Clean the fuel
cock.
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8-150
Engine overheating
NOTE:
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.
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.
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.
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