Yamaha YFM400FWA 2000 5GH3-AE1, Service Manual

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4 - 10
ENG
CYLINDER HEAD
NOTE:
●
Fasten a safety wire to the timing chain to
prevent it from falling into the crankcase.
●
When removing the camshaft sprocket, it
is not necessary to separate the timing
chain.
5.Remove:
●
Cylinder head
NOTE:
●
Loosen the 6 mm bolts first.
●
Working in a crisscross pattern, loosen
each 10 mm bolt 1/4 of a turn. After all the
bolts are loosened, remove them.
TAPPET COVER INSPECTION
1.Inspect:
●
Tappet covers 1
●
O-rings
2
Cracks/damage
→
Replace.
TIMING CHAIN TENSIONER INSPECTION
1.Check:
●
One-way cam operation (tensioner)
Unsmooth operation
→
Replace.
CAMSHAFT SPROCKET INSPECTION
1.Inspect:
●
Camshaft sprocket
Wear/damage
→
Replace the camshaft
sprocket and timing chain as a set.
a
1/4 of a tooth
b
Correct
1 Timing chain
2 Sprocket