TM 5-3810-307-24-2-2
Remove the valves and clean the lapping compound
from the valves and seats.
The valve should seat in the center of the valve face.
Measure the valve seat width indicated by the lapped
surface.
Valve Seat Width Limit
mm
in
1.5
MIN (1)
0.059
2.0
MAX (2)
0.079
Grind area (A) with a 60 degree stone and (B) with a
15 degree stone to center the seat on the valve face
and obtain the valve seat width limits.
Valve Seat Width Limit
mm
in
1.5
MIN
0.059
2.0
MAX
0.079
The lapped surface on the valve face is the key to
determining how much of each angle to grind.
If the lapped surface is at the bottom of the valve face,
the seat will require more grinding with the 60 degree
stone than with the 15 degree stone.
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