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ENG
INSPECTION AND REPAIR
●Apply a molybdenum disulfide oil to the
valve stem.
●Install the valve into the cylinder head.
●Turn the valve until the valve face and
valve seat are evenly polished, then clean
off all compound.
NOTE:
To obtain the best lapping result, lightly tap
the valve seat while rotating the valve back
and forth between your hand.
●Apply a fine lapping compound to the
valve face and repeat the above steps.
NOTE:
Be sure to clean off all compound from the
valve face and valve seat after every lap-
ping operation.
●Apply the Mechanic's bluing dye 2
(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.
●Remove the valve from the cylinder head.
●Measure the valve seat width a again. If
the valve seat width is out of specification,
reface and lap the valve seat.
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VALVE SPRING
1.Measure:
● Valve spring free length a (inner and
outer)
Out of specification → Replace.
Valve spring free length
Inner spring (IN/EX) Outer spring (IN/EX)
35.5 mm (1.4 in) 37.2 mm (1.46 in)
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