Honda GX120K1 Manual page 108

CYLINDER HEAD/VALVES
4. Use the 30°-32° and 60° cutters to narrow and adjust the valve
seat so that it contacts the middle of the valve face. The
30°-32° cutter removes material from the top edge (contact too
high).
The 60° cutter removes material from the bottom edge
(contact too low). Be sure that the width of the finished valve
seat is within specification.
VALVE SEAT WIDTH
Standard
0.8 mm (0.03 in)
5. Make a light pass with 45° cutter to remove any possible burrs
at the edges of the seat.
6. After resurfacing the seats, inspect for even valve seating.
Apply Prussian Blue compound or erasable felt-tipped marker
ink to the valve faces. Insert the valve, and snap it closed
against its seat several times. Be sure the valve does not
rotate on the seat.
The seating surface, as shown by the transferred marking
compound, should have good contact all the way around.
7. Lap the valves into their seats, using a hand valve lapper and
lapping compound (commercially available).
CAUTION
• To avoid severe engine damage, be sure to remove all
lapping compound from the engine before reassembly.
Note:
Adjust valve clearance after reassembly
9-8
gx120k1_gx160k1_gx200
Service limit
2.0 mm (0.08 in)
(P. 3-8).
GX120K1•GX160K1•GX200