Yamaha GRIZZLY Ultramatic YFM660FP, Service Manual

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ENG
VALVES AND VALVE SPRINGS
●
Install the valve into the cylinder head.
●
Turn the valve until the valve face and valve
seat are evenly polished, then clean off all of
the compound.
NOTE:
For best lapping results, lightly tap the valve
seat while rotating the valve back and forth
between your hands.
●
Apply a fine lapping compound to the valve
face and repeat the above steps.
NOTE:
After every lapping operation be sure to clean
off all of the compound from the valve face and
valve seat.
●
Apply Mechanic’s blueing dye (Dykem) to the
valve face.
●
Install the valve into the cylinder head.
●
Press the valve through the valve guide and
onto the valve seat to make a clear pattern.
●
Measure the valve seat width again. If the
valve seat width is out of specification, reface
and relap the valve seat.
*****************************************************
10.Measure:
●
Valve spring free length
a
Out of specification
→
Replace.
Free length (valve spring):
Intake:
32.63 mm (1.28 in)
<Limit>: 31.0 mm (1.22 in)
Exhaust:
36.46 mm (1.44 in)
<Limit>: 34.6 mm (1.36 in)