Yamaha Marine Outboards F4A/F4 Factory Service Manual, Page 192Get this manual

CRANKCASE, CRANKSHAFT AND CAMSHAFT
Oil splash gear unit inspection 1Inspect: 9Oil splash gear unit 9Gear teeth Unsmooth operation ReplaceWearDamageCrack Replace
Bearing inspection 1Inspect:
9Bearing

PittingRumbling ReplaceNOTE:

• ATV
• Jet Ski
• Outboard Motors
• Personal Watercraft
• Snowmobiles
• Stern Drives