ENGINE 3-33
FINAL SEAT CUT
• If the contact area
W is too low or too narrow, use the 45° cut-
ter to raise and widen the contact area.
NOTE:
After cutting the 15° angle, it is possible that the valve seat (45°)
is too narrow. If so, re-cut the valve seat to the correct width.
• After the desired seat position and width is achieved, use the
45° cutter very lightly to clean up any burrs caused by the pre-
vious cutting operations.
"
NOTE:
After servicing the valve seats, be sure to check the valve clear-
ance after the cylinder head has been reinstalled. (!2-5)
• Clean and assemble the head and valve components. Fill the
intake and exhaust ports with gasoline to check for leaks.
• If any leaks occur, inspect the valve seat and face for burrs or
other things that could prevent the valve from sealing.
)
The contact area too low and too
narrow on face of valve
Do not use lapping compound after the final cut is
made. The finished valve seat should have a velvety
smooth finish but not a highly polished or shiny fin-
ish. This will provide a soft surface for the final seat-
ing of the valve which will occur during the first few
seconds of engine operation.
Always use extreme caution when handling gasoline.