Komatsu 170-3 Series, Shop Manual, Page: 426 / 454

REPAIR AND REPLACEMENT OF PARTS
15-20
170-3 SERIES
(7)
2. Grinding couterbore
After grinding the top surface of the cylinder
block a , measure the depth of the counterbore.
If it is not within the standard dimension, or if
there are blackened portions on the cylinder liner
b contact surface of the counterbore (patricularly
in the front-to-rear direction), or there is speckled
wear, and these portions extend over more than
half of the contact width of the deck, correct the
counterbore depth L within the repair limit. After
correcting, if the counterbore depth is within
14.05
–
15.525 mm, combine with shims and
adjust so that the liner protrusion "
l
" is 0.07
–
0.15 mm.
a
Counterbore depth L:
Standard dimension 14 mm
Repair limit: 15.46 mm
a
Protrusion of cylinder liner "
l
" :
Standard value: 0.07
–
0.15 mm
a
Roughness of counterbore: Max. 12.5S (See
diagram on the right)
a
Machined shape: (See diagram on the right)
• Machine only the shaded area to adjust the
depth of part c of the counterbore.
• Machining dimension of part d: Max. 0.4 mm
• Machining dimension of part e: Max. 0.7 mm
• Machining dimension of part f:
0
–
Max. 0.06 mm
• Angle of part g to center (straight line) of cyl-
inder: 90
°
• Remove burrs from the tapered parts, etc.
• Letter h indicates the center of the cylinder.
• Set R to 0.2
–
0.4 mm.
For the extra amount for counterbore depth L,
decide the machining amount so that the protru-
sion of the cylinder liner will be within the stan-
dard value.
When grinding within the repair limit when coun-
terbore depth L exceeds the standard dimen-
sion, set the machining amount so that 1 of the
shims (1) shown below will be used for each cyl-
inder.
[Reference] Adjustment shims for counterbore depth
Unit: mm
a
Inside diameter j and outside diameter I of
shims (1)
•
I: 205.5
±
0.15 mm
• j: 194.6 mm
Part No. T t
Weight
(kg)
Remarks
6162-29-2260 1.50 0.025 0.004
6162-29-2250 0.80 0.025 0.002
6162-29-2240 0.50 0.025 0.001
6162-29-2230 0.26 0.025 0.001
6162-29-2220 0.20 0.020 0.001
6162-29-2210 0.16 0.016 0.001
+ 0.05
0
+ 30’
0
+ 0.030
0
GRINDING THE TOP SURFACE OF CYLINDER BLOCK
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