Service manual

03-26
VALVE SEAT REFACING
✰ Valve Seat cutters, a grinder or
equivalent valve seat refacing
equipment are recommended to
correct worn valve seat.
✰ If the contact area is too high on the
valve, the seat must be lowered using
a 32 degree flat cutter.
✰ If the contact area is too low on the
valve, the seat must be raised using
a 60 degree inner cutter.
NOTE :
Reface the valve seat with a 45 degree
cutter when a valve guide is replaced.
✰ Contact area is too high or too low.
re-face the valve seat.
Periodical Maintenance
✰ Use a 45 degree cutter to remove the
roughness or irregularities from the
seat.
✰ Using 32 degree cutter, remove top
1/4 of the existing valve seat material.
✰ Using 60 degree cutter, remove the
bottom 1/4 of the old seat.
✰ Remove the cutter and inspect the
area.
✰ Install a 45 degree finish cutter and
cut the seat to proper width.
✰ Make sure that all printing and
irregularities are removed. Refinish
if necessary.
Standard seat width : 0.9 - 1.1 mm