Kubota ZD21-EC, Workshop Manual

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1-S57
ZD21N-EC, ZD21-EC, ZD28-EC, WSM ENGINE
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.
W11613530
Oil Clearance between Crankpin and Crankpin Bearing (To be
continued)
1. Clean the crankpin and crankpin bearing.
2. Put a strip of plastigage (Code No. 07909-30241) 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 the
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.
[D782]
[D1105]
W11625390
Crankshaft alignment Allowable limit
0.02 mm
0.0008 in.
Oil clearance between
crankpin and crankpin
bearing
Factory spec.
0.020 to 0.051mm
0.00079 to 0.00201 in.
Allowable limit
0.15 mm
0.0059 in.
Crankpin O.D. Factory spec.
33.959 to 33.975 mm
1.33697 to 1.33760 in.
Crankpin bearing I.D. Factory spec.
33.995 to 34.010 mm
1.33839 to 1.33898 in.
Oil clearance between
crankpin and crankpin
bearing
Factory spec.
0.029 to 0.091mm
0.00114 to 0.00358 in.
Allowable limit
0.20 mm
0.0079 in.
Crankpin O.D. Factory spec.
39.959 to 39.975 mm
1.57319 to 1.57382 in.
Crankpin bearing I.D. Factory spec.
40.004 to 40.050 mm
1.57496 to 1.57677 in.
KiSC issued 09, 2006 A