10. CRANKCASE/CRANKSHAFT
SERVICE INFORMATION
GENERAL INSTRUCTIONS
· This section covers crankcase separation to service the crankshaft.
· The following parts must be removed before separating the crankcase.
Engine ( Section 5) Driven pulley ( Section 7)
Carburetor ( Section 12) A.C. generator ( Section9)
Oil pump ( Section 4) Cylinder head/cylinder ( Section 6)
Reed valve ( Section 12)
· When the left crankcase must be replaced, remove the following part in addition to the above.
Final reduction removal
· Special tools must be used for crankshaft and crankcase assembly. When separating the
crankcase, the bearing will remain in the crankcase and it should be removed. When,
assembling, drive a new bearing into the crankcase and install a new oil seal.
SPECIFICATIONS
SH10BA SH10AA
Item Standard (mm) Service Limit (mm) Standard (mm) Service Limit (mm)
Connecting rod big end side
clearance 0.60 0.60
Connecting rod big end radial
clearance 0.04 0.04
Crankshaft runout A/B 0.15/0.10 0.15/0.10
SPECIAL TOOLS
Crankcase puller Bearing outer driver handle A
Universal bearing puller Bearing outer driver, 42x47mm
Crankcase assembly collar Bearing driver pilot, 20mm
Crankcase assembly tool Bearing outer driver, 37x40mm
Bearing driver pilot, 17mm
TROUBLESHOOTING
Abnormal engine noise
· Excessive crank journal bearing play
· Excessive crankpin bearing play
· Excessive transmission bearing play
10-2
4.7 / 5