Komatsu SDA6D140E-3 - Page 97

140-3 SERIES
11-33
STRUCTURE AND FUNCTION, MAINTENANCE STANDARD PISTON • PISTON RING • PISTON PIN
Unit: mm
No. Check item Criteria Remedy
1
Outside diameter of
piston
Standard size Tolerance Repair limit
Replace
piston
140
–0.125
–0.155
139.81
2
|
4
Thickness of piston
ring
No. Measuring point Standard size Tolerance
Replace
piston ring
2 Top ring 2.9
–0.015
–0.035
3 Second ring 2.41
–0.010
–0.035
4Oil ring 4
–0.010
–0.030
Width of piston ring
groove
2 Top ring
Judge using groove wear gauge
Replace
piston
3 Second ring
4Oil ring 4
+0.040
+0.025
Clearance between
piston ring and ring
groove
No. Measuring point Standard clearance
Clearance
limit
Replace
piston or
piston ring
2 Top ring
Judge using groove wear gauge
3 Second ring
4 Oil ring 0.035 – 0.060 0.14
Piston ring gap
2 Top ring
0.42 – 0.57
(Tension 16.5 – 23.5N
{1.68 – 2.40kg})
2.0
Replace
piston ring
or cylinder
liner
3
Second ring
(Distinguishing
2RN white mark)
0.65 – 0.80
(Tension 16.2 – 24.2N
{1.65 – 2.47kg})
1.5
4Oil ring
0.30 – 0.50
(Tension 70.1 – 94.6N
{7.15 – 9.65kg})
1.0
5
Outside diameter of
piston pin
Standard size Tolerance
Replace
piston pin
52
0
–0.006
Inside diameter of
piston pin hole
52
+0.045
+0.035
Replace
piston
Clearance between
piston pin and piston
Standard clearance Clearance limit Replace
piston or
piston pin
0.035 – 0.051 0.10