Yamaha GRIZZLY 660 YFM66FAV Owner's Manual page 322

CAUTION:
_
G
In 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 spec-
ified. In addition, do not use oils labeled
"ENERGY CONSERVING II" or higher.
G
Make sure that no foreign material enters
the crankcase.
_
12. Start the engine and warm it up for several
minutes. While warming up, check for oil
leakage. If oil leakage is found, turn the en-
gine off immediately and check for the cause.
13. Turn the engine off, and then check the oil
level and correct it if necessary.
14. Install panel F.
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