wsm M6060, Workshop Manual

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ENGINE M6060, M7060, WSM
1-S70
Clearance between Piston Ring and Ring 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.
9Y1210828ENS0110US0
(4) Crankshaft
Side Clearance of Crankshaft
1. Set a dial indicator with its point on the end of the crankshaft (1).
2. Move the crankshaft (1) 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
9Y1210828ENS0111US0
Clearance between
piston ring and ring
groove
Factory
specifica-
tion
Top ring
0.050 to 0.090 mm
0.0020 to 0.0035 in.
Second
ring 0.090 to 0.12 mm
0.0036 to 0.0047 in.
Oil ring
0.020 to 0.060 mm
0.00079 to 0.0023 in.
Allowable
limit
Top ring
0.15 mm
0.0059 in.
Second
ring 0.20 mm
0.0079 in.
Oil ring
0.15 mm
0.0059 in.
Side clearance of
crankshaft
Factory specification
0.15 to 0.35 mm
0.0059 to 0.013 in.
Allowable limit
0.50 mm
0.020 in.
Oversize
0.2 mm
0.008 in.
0.4 mm
0.02 in.
Dimension A
41.10 to 42.10 mm
1.619 to 1.657 in. 41.20 to 42.20 mm
1.622 to 1.661 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
2.8 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 = 0.8S
(1) Crankshaft (A) Side Clearance of Crankshaft
KiSC issued 08, 2013 A