Kubota G23, Workshop Manual

Page: 139 / 343

ENGINE
G23, G26, WSM
1-S57 (EU)
(4) Crankshaft
Crankshaft Side Clearance
1. Set a dial indicator with its tip on the end of the crankshaft.
2. Measure the side clearance by moving the crankshaft to the
front and rear.
3. If the measurement exceeds the allowable limit, replace the
thrust bearings.
4. If the same size bearing is useless because of the crankshaft
journal wear, replace it with an oversize one referring to the
table and figure.
(Reference)
[G23]
• Oversize thrust bearing
• Oversize dimensions of crankshaft journal
[G26]
9Y1210294ENS0075US0
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.
9Y1210294ENS0076US0
Crankshaft side
clearance
Factory specification
0.15 to 0.31 mm
0.0059 to 0.012 in.
Allowable limit
0.50 mm
0.020 in.
Oversize Bearing Code Number Marking
0.20 mm
0.0079 in.
Thrust bearing 1 02 15261-23950 020 OS
Thrust bearing 2 02 15261-23970 020 OS
0.40 mm
0.016 in.
Thrust bearing 1 04 15261-23960 040 OS
Thrust bearing 2 04 15261-23980 040 OS
Oversize
0.20 mm
0.0079 in.
0.40 mm
0.016 in.
Dimension
A
46.10 to 46.30 mm
1.815 to 1.822 in.
46.30 to 46.50 mm
1.823 to 1.830 in.
Dimension
B
23.40 to 23.45 mm
0.9213 to 0.9232 in.
23.80 to 23.85 mm
0.9370 to 0.9389 in.
Dimension
C
1.8 to 2.2 mm radius
0.071 to 0.086 in. radius
1.8 to 2.2 mm radius
0.071 to 0.086 in. radius
The crankshaft journal must be fine-finished to higher than Rmax=0.8S
Oversize
0.20 mm
0.0079 in.
0.40 mm
0.016 in.
Dimension
A
51.50 to 51.70 mm
2.028 to 2.035 in.
51.60 to 51.80 mm
2.032 to 2.039 in.
Dimension
B
28.20 to 28.25 mm
1.111 to 1.112 in.
28.40 to 28.45 mm
1.119 to 1.120 in.
Dimension
C
2.3 to 2.7 mm radius
0.091 to 0.10 in. radius
2.3 to 2.7 mm radius
0.091 to 0.10 in. radius
The crankshaft journal must be fine-finished to higher than Rmax=0.8S
Crankshaft alignment Allowable limit
0.02 mm
0.0008 in.
KiSC issued 08, 2009 A