Kubota SM-E4B Series Workshop Manual page 126

SM-E4B SERIES, WSM
Crankshaft Alignment
1. Support the crankshaft with V blocks on the surface plate at
both end journals.
2. Set a dial indicator with its tip on the intermediate journal.
3. Measure the crankshaft alignment.
4. If the measurement exceeds the allowable limit, replace the
crankshaft.
Crankshaft alignment Allowable limit
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.
Factory specification
Oil clearance between
crankpin and crankpin
bearing
Allowable limit
Crankpin O.D. Factory specification
Crankpin bearing I.D. Factory specification
(Reference)
• Undersize crankpin bearing
Undersize Bearing
0.20 mm
Crankpin bearing 02
0.0079 in.
0.40 mm
Crankpin bearing 04
0.016 in.
• Undersize dimensions of crankpin
Undersize
2.3 to 2.7 mm radius
Dimension A
0.091 to 0.10 in.radius
1.0 to 1.5 mm relief
*Dimension B
0.040 to 0.059 in. relief
33.759 to 33.775 mm dia.
Dimension C
1.3291 to 1.3297 in. dia.
The crankpin must be fine-finished to higher than Rmax. = 0.8S
*Holes to be de-burred and edges rounded with 1.0 to 1.5 mm
(0.040 to 0.059 in.) relief.
1-S62
0.02 mm
0.0008 in.
9Y1210785ENS0090US0
0.020 to 0.051 mm
0.00079 to 0.0020 in.
0.15 mm
0.0059 in.
33.959 to 33.975 mm
1.3370 to 1.3375 in.
33.995 to 34.010 mm
1.3384 to 1.3389 in.
Code Number
15861-22970
15861-22980
0.20 mm 0.40 mm
0.0079 in. 0.016 in.
2.3 to 2.7 mm radius
0.091 to 0.10 in.radius
1.0 to 1.5 mm relief
0.040 to 0.059 in. relief
33.559 to 33.575 mm dia.
1.3213 to 1.3218 in. dia.
9Y1210785ENS0091US0
ENGINE
Marking
020 US
040 US
KiSC issued 01, 2013 A