Yamaha 55DEHD Service Manual page 161

9. While pushing the drive shaft slightly, turn
the drive shaft slowly clockwise and
counterclockwise, then measure the
backlash when the drive shaft stops in
each direction.
Reverse gear backlash:
0.67–1.00 mm
(0.0264–0.0394 in)
10. Add or remove the shim(s) if out of spec-
ification.
Reverse gear
backlash
Less than
0.67 mm (0.0264 in)
More than
1.00 mm (0.0394 in)
M: Measurement
Available shim thicknesses:
0.10, 0.12, 0.15, 0.18, 0.30, 0.40 and
0.50 mm
11. Remove the special service tools, and
then install the water pump assembly.
6885J11
68860520
Shim thickness
To be increased by
(0.84 – M) × 0.60
To be decreased by
(M – 0.84) × 0.60
Backlash
1
2
3
4
5
6
7
8
9
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