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5-27
EAS00240
CHECKING THE VALVE SEATS
The following procedure applies to all of the
valves and valve seats.
1. Eliminate:
8carbon deposits
(from the valve face and valve seat)
2. Check:
8valve seat
Pitting/wear J Replace the cylinder head.
3. Measure:
8valve seat width a
Out of specification J Replace the cylin-
der head.
Valve seat width
Intake: 0.9 ~ 1.1mm (0.035 ~
0.043in)
<Limit>: 1.6mm (0.063in)
Exhaust: 0.9 ~1.1mm (0.035 ~
0.043in)
<Limit>: 1.6mm (0.063in)
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a. Apply Mechanic’s blueing dye (Dykem) b
onto the valve face.
b. Install the valve into the cylinder head.
c. Press the valve through the valve guide and
onto the valve seat to make a clear impres-
sion.
d. Measure the valve seat width.
TIP
Where the valve seat and valve face contacted
one another, the blueing will have been removed.
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VALVES AND VALVE SPRINGS
4. Lap:
8valve face
8valve seat
TIP
After replacing the cylinder head or replacing
the valve and valve guide, the valve seat and
valve face should be lapped.
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