Yamaha F40B - Checking the Connecting Rod Big End Side Clearance; Checking the Crankshaft; Checking the Crankpin Oil Clearance

67C3K11 5-46
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Checking the connecting rod big end
side clearance
1. Measure the connecting rod big end side
clearance a.
Checking the crankshaft
1. Measure the crankshaft journal diame-
ters a, crankpin diameters b, and
crankpin widths c. Replace the crank-
shaft if out of specification.
2. Measure the crankshaft runout. Replace
if above specification.
Checking the crankpin oil clearance
1. Clean the bearings, connecting rods and,
crankpin.
2. Put a piece of Plastigauge (PG-1) onto
the crankpin, parallel to the crankshaft.
NOTE:
Be sure not to put the Plastigauge (PG-1)
over the oil hole in the crankpin of the crank-
shaft.
Connecting rod big end side
clearance a (reference data):
0.12–0.15 mm (0.0047–0.0059 in)
S67C5135
a
a
S67C5136
a
a
S67C5137
c
b
Crankshaft journal diameter a:
42.984–43.000 mm
(1.6923–1.6929 in)
Crankpin diameter b:
32.984–33.000 mm
(1.2986–1.2992 in)
Crankpin width c:
21.000–21.070 mm
(0.8268–0.8295 in)
Crankshaft runout limit:
0.05 mm (0.0020 in)
S67C5138
S6AU5144
Cylinder block