Checking The Crankshaft; Checking The Connecting Rod Big End Side Clearance - Yamaha 55DEHD Service Manual

1
Piston ring end gap a: (reference
data)
Top and 2nd piston ring:
0.40–0.60 mm
(0.0157–0.0236 in)
Measuring point b:
10.0 mm (0.39 in)

Checking the crankshaft

1. Measure the crankshaft journal diameter
a and crankpin diameter b. Replace the
crankshaft if out of specification.
a
b
Crankshaft journal diameter a:
34.968–34.984 mm
(1.3767–1.3773 in)
Crankpin diameter b:
29.985–30.000 mm
(1.1805–1.1811 in)
6885J11
b
1
a
68850440
68850480
68850490
2. Measure the crankshaft runout. Replace
the crankshaft if above specification.
c c c
Crankshaft runout limit c:
0.02 mm (0.0008 in)
Checking the connecting rod big
end side clearance
1. Install the bearing and connecting rod.
2. Measure the connecting rod big end side
clearance a. Replace the connecting rod
or crankshaft or both if out of specifica-
tion.
Connecting rod big end side
clearance a: (reference data)
0.120–0.260 mm
(0.0047–0.0102 in)
Crankcase
1
c
2
68850500
3
4
5
6
7
a
68850470
8
9
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