DE08TS Diesel Engines
Maintenance
b. Valve guide
• Insert a valve into cylinder head and measure the
clearance between valve guide and valve by valve
movement. If the clearance is excessive, measure
the valve and replace the excessively worn valve or
valve guide.
<Valve stem end play>
• Assemble the valve at cylinder head’s valve guide
and see if it is centered with the valve seat using a
special tool.
c. Valve seat
• Contacting face amount
As for the valve seat’s wear, measure the width of
the contact surface with intake valve seat and
exhaust valve seat. If beyond the limit value, replace
the valve seat.
• Assemble the valve at the valve seat of 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 the disassembling of valve seat, by welding the
welding bead to a valve seat rotating tool or valve
seat, pull it out with a special tool.
• For the assembling of a new valve seat, by putting it
among the dry ices of an ice box previously for about
2 hours for the cold shrinkage, and press it in the
cylinder head by 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.
d. Valve spring
• Visual check
Check the appearance of valve spring and if neces-
sary replace the spring.
EA3M2032
Valve seat
insert
Welding bead
Cylinder head
EA0M4046
EDM2032P
Measuring
position
EA0M4052
39
Dimension
Standard
Limit
Description
Intake valve
0.04 ~ 0.07 mm
0.2 mm
Exhaust valve
0.06 ~ 0.09 mm
0.25 mm
Standard
Limit
Intake &
0 ~ 0.3 mm
0.55 mm
Exhaust
