Yamaha F25C Service Manual page 142

LOWR
10. Add or remove shim(s) if out of specifica-
tion.
Reverse gear
backlash
Less than
0.92 mm (0.0362 in)
More than
1.65 mm (0.0650 in)
M: Measurement
Available shim thicknesses:
1.0, 1.1, 1.2, and 1.3 mm
11. Remove the special service tools, and
then install the water pump assembly.
6-29
Lower unit
Shim thickness
To be decreased by
(1.29 – M) × 0.49
To be increased by
(M – 1.29) × 0.49
6D55F11