3) Valve seat
•
Contacting face amount
Measure the contacting face between
the intake valve seat and exhaust valve
seat for valve seat wear, and replace if
the measured value exceeds the speci-
fied limit.
•
Install the valve into the valve seat on
the cylinder head, and check the amount
of depression of the valve from the lower
portion of the cylinder head using a dial
gauge.
Valve depression
If the amount of depression is beyond the
specified limit, replace the valve seat.
•
For removal of the valve seat, apply arc
welding work to two points of valve seat
insert, and pull out the valve seat insert
with inner extractor.
•
Undercool a new valve seat with dry ice
for about 2 hours and press the valve
seat insert into position in the cylinder
head using a special tool (bench press).
•
Apply valve lapping compound to the
valve head seating face on the valve
seat and lap the valve seat by turning it
until it is seated in position, then wipe out
the lapping compound.
- 44 -
EA0M4046
EA3M2032
Valve seat
insert
Welding bead
Cylinder head
Standard
Limit
Intake &
0 ~ 0.3 mm
0.55 mm
Exhaust
