Yamaha F100B F100C Outboards Factory Service Manual, Page 203Get this manual
Shimming (F100C)Backlash (F100C) Calculation formula: Forward gear shim thickness (T1)24.50F100 Example: If "M" is 24.00 mm and "F" is (+5), then T124.50(+5)100 24.00 mm0.500.05 mm0.55 mm If "M" is 24.00 mm and "F" is (5), then T124.50(5)100 24.00 mm0.50 0.05 mm0.45 mm 3Select the forward gear shim(s) (T1) as followsCalculated numeral at 1100 place 1, 3, 4, 6, 7, 9, 10 Rounded numeral 3Install the special service tool so that it pushes against the propeller shaftShift rod push arm: 90890-06052
Backlash (F100C)
1Remove the water pump assembly2Set the gearshift to the neutral position
Measuring the forward gear backlash