wsm M7040 - Page 208

ENGINE
M6040, M7040, WSM
1-S76
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.
IMPORTANT
• STD size crankpin bearing.To replace it with a specific STD
service part, make sure the crankpin bearing has the same
ID color as the connecting rod.
(Reference)
• Undersize dimensions of crankpin
9Y1210143ENS0122US0
Crankpin O.D. Factory specification
49.980 to 49.991 mm
1.9677 to 1.9682 in.
Oil clearance between
crankpin and crankpin
bearing
Factory specification
0.017 to 0.048 mm
0.0007 to 0.0019 in.
Allowable limit
0.20 mm
0.0079 in.
ID
Color
Connecting rod Crankpin bearing
Large-end in. dia. Class Part code Center wall thick
Blue
53.010 to 53.020 mm
2.0870 to 2.0874 in.
L
1G772
-22310
1.496 to 1.501 mm
0.05890 to
0.05909 in.
Without
color
53.000 to 53.010 mm
2.0867 to 2.0870 in.
S
1G772
-22330
1.491 to 1.496 mm
0.05870 to
0.05889 in.
Undersize
0.20 mm
0.0079 in.
0.40 mm
0.016 in.
Dimension A
3.3 to 3.7 mm radius
0.13 to 0.14 in. radius
3.3 to 3.7 mm radius
0.13 to 0.14 in. radius
*Dimension B
1.0 to 1.5 mm relief
0.040 to 0.059 in. relief
1.0 to 1.5 mm relief
0.040 to 0.059 in. relief
Dimension C
49.780 to 49.791 mm dia.
1.9599 to 1.9602 in. dia.
49.580 to 49.591 mm dia.
1.9520 to 1.9524 in. dia.
The crankshaft journal 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) Connecting Rod Cap
(2) Connecting Rod Screw
(3) ID Color
(4) Crankpin Bearing
(5) Center Wall Thick
KiSC issued 07, 2012 A