Doosan D1146, Installation Operation & Maintenance

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(3) 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 pre-
viously for about 2 hours for the c o l d s h r i n k a g e , a n d p r e s s i t i n t h e 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.
- 82 -
Standard Limit
Intake &
0 ~ 0.3 mm 0.55 mm
Exhaust
침하량
EA0M4046
EA3M2032
Valve seat
insert
Welding bead
Cylinder head
Depression
EDM2032P