Yamaha 250GETO Service Manual page 166

LOWR
8. Remove the special service tools from
the propeller shaft.
9. Apply a load to the reverse gear by
installing the propeller 8, the spacer 9
(without the washer 0), then the washer
q as shown.
NOTE:
While turning the drive shaft clockwise and
counterclockwise 5-6 times to contact the
gear evenly it tightens propeller nut w to
specified torque.
Propeller nut w:
5 N·m (0.5 kgf·m, 3.7 ft·lb)
6-29
Lower unit
6S360200
10. Slowly turn the drive shaft clockwise and
counterclockwise, and measure the
backlash when the drive shaft stops in
each direction.
Reverse gear backlash:
0.64–0.93 mm
(0.0252–0.0366 in)
11. Add or remove shim(s) if out of specifica-
tion.
Reverse gear
backlash
Less than
0.64 mm (0.0251 in)
More than
0.93 mm (0.0366 in)
M: Measurement
Available shim thicknesses:
0.10, 0.12, 0.15, 0.18, 0.30, 0.40 and
0.50 mm
12. Remove the special service tools, and
then install the water pump assembly.
Shim thickness
To be decreased by
(0.79 – M) × 0.78
To be increased by
(M – 0.79) × 0.78
6S35H11