Checking The Valve Seats - Yamaha XJR1300(L) 99 Service Manual

VALVES AND VALVE SPRINGS
EAS00240

CHECKING THE VALVE SEATS

The following procedure applies to all of the
valves and valve seats.
1. Eliminate:
2. Check:
3. Measure:
a. Apply Mechanic's blueing dye (Dykem) b
b. Install the valve into the cylinder head.
c. Press the valve through the valve guide and
d. Measure the valve seat width. Where the
4. Lap:
NOTE:
After replacing the cylinder head or replacing
the valve and valve guide, the valve seat and
valve face should be lapped.
a. Apply a coarse lapping compound a to the
CAUTION:
Do not let the lapping compound enter the
gap between the valve stem and the valve
guide.
b. Apply molybdenum disulfide oil onto the
c. Install the valve into the cylinder head.
4-22
S carbon deposits
(from the valve face and valve seat)
S valve seat
Pitting/wear ! Replace the cylinder head.
S valve seat width a
Out of specification ! Replace the cylinder
head.
Valve seat width
Intake: 0.9 X 1.1 mm
Exhaust: 0.9 X 1.1 mm
onto the valve face.
onto the valve seat to make a clear pattern.
valve seat and valve face contacted one
another, the blueing will have been removed.
S valve face
S valve seat
valve face.
valve stem.
ENG