2006 YAMAHA YFZ450 heating

6-19
EBU02092
Engine break-in
There is never a more important period in the
life of your machine than the period between
zero and 20 hours.
For this reason, we ask that you carefully read
the following material. Because the engine is
brand new, you must not put an excessive load
on it for the first several hours of running. During
the first 20 hours, the various parts in the engine
wear and polish themselves to the correct oper-
ating clearances.
During this period, prolonged full throttle opera-
tion or any condition which might result in exces-
sive engine heating must be avoided. However,
momentary (2-3 seconds maximum) full throttle
operation under load does not harm the engine.
Each full throttle acceleration sequence should
be followed with a substantial rest period for the
engine by cruising at lower r/min so the engine
can rid itself of the temporary build up of heat.
If any abnormality is noticed during this period,
consult a Yamaha dealer.
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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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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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