Yamaha F100B F100C Outboards Factory Service Manual, Page 193Get this manual
Drive shaft and lower case (F100C) Disassembling the lower case
1Remove the taper roller bearing outer race and shim(s)3Remove the needle bearing
NOTE: Install the claws as shownBearing outer race puller 1: 90890-06523 Outer race puller claw 2: 90890-06532 2Remove the drive shaft bearing outer race, shim(s), and drive shaft sleeve
Needle bearing attachment 7: 90890-06611 Driver rod L3 8: 90890-06652
Checking the pinion and forward gear
1Check the teeth of the pinion, and the teeth and dogs of the forward gear for cracks or wearReplace if necessary