Section 4 Disassembly and service
material from the bottom edge. Bu sure that the width
of the finished valve seat is within specification.
Valve seat width
Standard
Service limit
0.8 mm (0.03 in)
2.0 mm (0.08)
1. make a light pass with the 45° cutter to remove
any possible burrs at the edges of the seat.
2. after resurfacing the seats, inspection for even
valve seating.
3. apply a light coat of Prussian Blue or erasable
felt-tipped marker ink to the valve faces.
4. insert the valves, and then lift them and snap
them closed against their seats several times. Be
sure the valve does not rotate on the seat. The
seating surfacing, as shown by the transferred
marking compound, should have good contact all
the way around.
Notice
To avoid severe engine damage, be sure to
remove all lapping compound from the head
before reassembling.
5. check the valve clearance after reassembly.
HAND VALVE LAPPER
4-23