ENGINE
L3301, L3901, L4701, WSM
1-S73
Clearance between Piston Ring and Groove
1. Clean the rings and the ring grooves, and install each ring in its
groove.
2. Measure the clearance between the ring and the groove with a
feeler gauge or depth gauge.
3. If the clearance is more than the allowable limit, replace the
piston ring.
4. If the clearance stays more than the allowable limit with new
ring, replace the piston also.
9Y1211012ENS0098US0
[4] CRANKSHAFT
Side Clearance of Crankshaft
1. Set a dial indicator with its point on the end of the crankshaft.
2. Move the crankshaft to the front and rear to measure the side
clearance.
3. If the measurement is more than the allowable limit, replace the
thrust bearings.
4. If the same dimension bearing is not applicable because of the
crankshaft journal wear, replace it with an oversize one. Refer
to the table and figure.
(Reference)
• Oversize dimensions of crankshaft journal
9Y1211012ENS0099US0
Top ring
Factory specification
0.050 to 0.090 mm
0.0020 to 0.0035 in.
Allowable limit
0.20 mm
0.0079 in.
Second ring
Factory specification
0.0780 to 0.110 mm
0.00307 to 0.00433 in.
Allowable limit
0.20 mm
0.0079 in.
Oil ring
Factory specification
0.030 to 0.070 mm
0.0012 to 0.0027 in.
Allowable limit
0.15 mm
0.0059 in.
Side clearance of
crankshaft
Factory specification
0.15 to 0.31 mm
0.0059 to 0.012 in.
Allowable limit
0.5 mm
0.02 in.
Oversize
0.2 mm
0.008 in.
0.4 mm
0.02 in.
Dimension A
54.50 to 54.70 mm
2.146 to 2.153 in.
54.60 to 54.80 mm
2.150 to 2.157 in.
Dimension B
26.20 to 26.25 mm
1.032 to 1.033 in.
26.40 to 26.45 mm
1.040 to 1.041 in.
Dimension C
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
The crankshaft journal must be fine-finished to higher than Rmax = 0.4S