Doosan DP158L Series, Руководство по эксплуатации и техническому обслуживанию

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10. Cylinder block/head
157
2. Valve seat thickness and angle: Assemble the valves at
the cylinder head and using the measuring instrument
from the lower face, measure the projection amount of
valve. If the measured wear is excessive, replace the
valve seat.
EDP2218013
3. The disassembly of valve seat cam be pulled out by
means of a special tool with the arc welding done at two
points of valve seat rotating tool or valve seat.
DV2213122A_E
4. Regarding the valve seat assembling, shrink the valve
seat by putting it in the dry ices for about 1 hour or so, and
then press it into the cylinder head by means of a special
tool.
5. After coating the grinding powder paste on valve head
contacting face of valve seat, and after executing a suffi-
cient lapping operation with the rotating and grinding
motion of valve, wipe off the grinding agent thoroughly.
Valve Spring
1. Visual inspection: Check if the exterior of the valve spring
is damaged with the naked eye. Replace it with a new
one if required.
2. Fee length of valve spring: Measure the free length of the
valve spring with the vernier clipers. If the reading is
larger than the specified valve, replace the valve spring.
DV2213123A
<Dual Spring Perpendicularity Regular>
<Single Spring Perpendicularity Regular>
<Single Spring Perpendicularity Regular>
Item Limit
Valve projecting
amount
In. Valve 0.65 ~ 0.95mm
Ex. Valve 0.65 ~ 0.95mm
Item Limit
Valve seat angle
In. Valve 60
°
Ex. Valve
45
°
B
A
Val v e
Val v e S eat
Cy lin d er hea d
Valve sheet
Wel d bea d
Item Free Length
Spring
Inside 65.5mm
Outside 64mm
Item Free Length
Intake / Exhaust Outside 61.9mm
Item
Length
(mm)
Spring
Tension
(kg)
Limit
(kg)
Intake /
Exhaust
Outside
46.8/
32.8
47.0/
90.5
±2.5/
±4.5