ENGINE 3-29
VALVE SEAT SERVICING
The valve seats for intake and exhaust valves are machined to
two different angles. The seat contact surface is cut at 45°.
NOTE:
The valve seat contact area must be inspected after each cut.
09916-21111: Valve seat cutter set
09916-24900: Valve seat cutter set
09916-22480: Solid pilot (N-140-5.5)
09916-24450: Solid pilot (N-100-5.52)
09916-24935: Valve seat cutter (N-608)
• When installing the solid pilot, ratate it slightly. Seat the pilot
snugly. Install the 45° cutter, attachment and T-handle.
• Using the 45° cutter, descale and clean up the seat. Rotate
the cutter one or two turns.
• Measure the valve seat width after every cut.
• If the valve seat is pitted or burned, use the 45° cutter to con-
dition the seat some more.
INITIAL SEAT CUT
• Using the 45° cutter, descale and clean up the seat. Rotate
the cutter one or two turns.
• Measure the valve seat width W after every cut.
• If the valve seat is pitted or burned, use the 45° cutter to con-
dition the seat some more.
NOTE:
Cut only the minimum amount necessary from the seat to pre-
vent the possibility of the valve stem becoming too close to the
camshaft.
INTAKE EXHAUST
15° N-212 N-121
45° N-608 N-122
Valve seat
To Next Page
Loading...
