Yamaha F100B F100C Outboards Factory Service Manual, Page 187Get this manual
Propeller shaft housing (F100C) 2Check the teeth and dogs of the reverse gear for cracks or wearReplace the gear if necessary
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Needle bearing attachment 0: 90890-06612 Driver rod L3 A: 90890-06652
3Check the bearings for pitting or rumblingReplace if necessary
Disassembling the propeller shaft assembly
1Remove the spring 1, and then remove the cross pin 2, dog clutch 3, slider, and shift plunger 4S60C6130