Mitsubishi S4S Service Manual page 69

(5) Refacing valve face
If the valve face is badly wom, reface it with a
valve refacer.
NOTE
1 - - - - - - - - - ,
a) Set a valve refacer to an angle of 30°
b) The valve has a stellate facing. This facing
will be gone if the valve margin exceeds the
service limit. If the margin seems to be less
than the service limit when ground, replace
the valve.
(6) Refacing valve seat
Use the Valve seat cutter or valve seat grinder to
reface the valve seat. After refacing, grind the
seat lightly using #400 grade sandpaper inserted
between the cutter and valve seat.
NOTE
1 - - - - - - - - - ,
a) Cut or grind the valve seat only as needed
for refacing.
b) Replace the valve seat if the seat width is
more than the repair limit as a result of wear
or cutting.
(7) Replacing valve seat
(a) Weld a stud to the valve seat. Insert a shaft
into the valve guide holder from the upper
side of the cylinder head. Drive the seat off
from the cylinder head as shown.
. - - - - - - - - I (
NOTE
11-- ---,
When you weld the stud, do not to permit splatter
to come in contact with the machined surfaces
of cylinder head.
ENGINE MAIN PARTS
Refacing valve face
Refacing valve seat
Stud
Removing valve seat
7-7