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EBU00209
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. Dur-
ing the first 20 hours, the various parts in the
engine wear and polish themselves to the cor-
rect operating clearances.
During this period, prolonged full throttle oper-
ation or any condition which might result in ex-
cessive engine heating must be avoided.
However, momentary (2 ~ 3 seconds maxi-
mum) 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 en-
gine can rid itself of the temporary build up of
heat.
If any abnormality is noticed during this peri-
od, 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 lubri-
cated more often if the machine is operated in
extremely dusty areas. Each time the filter ele-
ment maintenance is performed, check the air
inlet to the filter case for obstructions. Check
the air cleaner rubber joint to the carburetor
and manifold fittings for an airtight seal. Tight-
en all fittings securely to avoid the possibility
of unfiltered air entering the engine.
CAUTION:
Never operate the engine with the air filter el-
ement removed. This will allow unfiltered air
to enter, causing rapid engine wear and possi-
ble engine damage. Additionally, operation
without the filter element will affect carbure-
tor jetting with subsequent poor performance
and possible engine overheating.
1. Hose
1. Flexible
1. Manguera
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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.
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.