Kubota M108S, Workshop Manual

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1-S62
M108S, WSM ENGINE
Oil Clearance between Crankpin and Crankpin Bearing
1. Clean the crankpin and crankpin bearing.
2. Put a strip of plastigage on the center of the crankpin.
3. Install the connecting rod cap and tighten the connecting rod
screws to the specified torque, and remove the cap again.
4. Measure the amount of the flattening with the scale, and get the
oil clearance.
5. If the oil clearance exceeds the allowable limit, replace the
crankpin bearing.
6. If the same size bearing is useless because of the crankpin wear,
replace it with an undersize one referring to the table and figure.
NOTE
■
• Never insert the plastigage into the crankpin oil hole.
• Be sure not to move the crankshaft while the connecting rod
screws are tightened.
IMPORTANT
■
• STD size crankpin bearing.
To replace it with a specific STD service part, make sure the
crankpin bearing has the same ID color as the connecting
rod.
(Reference)
• Undersize dimensions of crankpin
W1067389
Crankpin O.D. Factory spec.
52.977 to 52.990 mm
2.0857 to 2.0862 in.
Oil clearance between
crankpin and crankpin
bearing
Factory spec.
0.018 to 0.051 mm
0.00071 to 0.0020 in.
Allowable limit
0.20 mm
0.0079 in.
ID Color
Connecting rod Crankpin bearing
Large-end in. dia. Class Part code Center wall thick
Blue
56.010 to 56.020 mm
2.2052 to 2.2055 in.
L 1C020-22311
1.496 to 1.501 mm
0.05890 to 0.05909 in.
Without
color
56.000 to 56.010 mm
2.2048 to 2.2051 in.
S 1C020-22331
1.491 to 1.496 mm
0.05870 to 0.05889 in.
Undersize
0.2 mm
0.008 in. 0.4 mm
0.02 in.
Dimension A
2.8 to 3.2 mm radius
0.11 to 0.12 in. radius 2.8 to 3.2 mm radius
0.11 to 0.12 in. radius
*Dimension B
1.0 to 1.5 mm relief
0.040 to 0.059 in. relief 1.0 to 1.5 mm relief
0.040 to 0.059 in. relief
Dimension C
52.777 to 52.790 mm dia.
2.0779 to 2.0783 in. dia. 52.577 to 52.590 mm dia.
2.0700 to 2.0704 in. dia.
(0.8S)
The crankpin must be fine-finished to higher than
∇∇∇∇.
*Holes to be de-burred and edges rounded with 1.0 to 1.5 mm
(0.040 to 0.059 in.) relief.
(1) ID Color
(2) Crankpin Bearing (3) Center Wall Thick
KiSC issued 06, 2007 A