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.
4) Valve spring
Visual check
Check the appearance of valve spring and if
necessary replace the spring.
Valve spring free length
Use a vernier caliper to measure the valve spring free
length.
If the measured value is less than the specified limit,
the valve spring must be replaced.
Valve spring inclination
Use a surface plate and a square to measure the
valve spring inclination.
If the measured value exceeds the specified limit, the
valve spring must be replaced.
5ton Diesel Engine SPC000006
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