Inspection - Yamaha RS90GTZ Service Manual

CRANKSHAFT AND BALANCER SHAFT

INSPECTION

1. Measure:
• Crankshaft runout
Use the V-blocks and a dial indicator gauge
(dial gauge).
Out of specification → Replace the crank-
shaft.
Dial indicator gauge:
YU-A8428
Dial gauge:
90890-03097
Crankshaft runout:
0.03 mm (0.0012 in)
2. Inspect:
• Crankshaft journal surfaces
• Crankshaft pin surfaces
• Bearing surfaces
Scratches/wear → Replace the crankshaft.
3. Inspect:
• Bearings
Clean and lubricate the bearings, then
rotate the inner race with your finger.
Rough movement → Replace.
4. Inspect:
• Balancer drive gear
• Balancer driven gear
Damage/wear → Replace the crankshaft
assembly and balancer driven gear as a
set.
Excessive noise
Replace the crankshaft assembly and bal-
ancer driven gear as a set.
5. Inspect:
• Primary sheave drive shaft assembly
Damage → Replace.
5-80
ENG
→
during operation