Yamaha F100B F100C Outboards Factory Service Manual, Page 177Get this manual
Shimming (F100B)Backlash (F100B) Backlash indicator 4: 90890-06706 Magnet base plate 5: 90890-07003 Dial gauge set 6: 90890-01252 Magnet base 7: 90890-06705 6Slowly turn the drive shaft clockwise and counterclockwise and measure the backlash when the drive shaft stops in each directionForward gear backlash: 0.190.53 mm (0.0070.021 in) 7Add or remove shims if out of specificationForward gear backlash Less than 0.19 mm (0.007 in) More than 0.53 mm (0.021 in) M: Measurement Available shim thicknesses: 0.10, 0.12, 0.15, 0.18, 0.30, 0.40, and 0.50 mm 8Remove the special service tools from the propeller shaft9Apply load to the reverse gear by installing the propeller 8, the spacer (without the washer 0), then the washer as shownShim thickness To be decreased by (0.36 M) 0.58 To be increased by (M 0.36) 0.58 Reverse gear backlash: 0.861.26 mm (0.0340.050 in) 11Add or remove shims if out of specificationReverse gear backlash Less than 0.86 mm (0.034 in) More than 1.26 mm (0.050 in) M: Measurement Available shim thicknesses: 0.10, 0.12, 0.15, 0.18, 0.30, 0.40, and 0.50 mm 12Remove the special service tools, and then install the water pump assemblyShim thickness To be increased by (1.06 M) 0.58 To be decreased by (M 1.06) 0.58 NOTE: Tighten the propeller nut while turning the drive shaft until the drive shaft can no longer be turned10Slowly turn the drive shaft clockwise and counterclockwise, and measure the backlash when the drive shaft stops in each direction