Yamaha 50G Service Manual page 120

LOWR
SHIM SELECTION
60, 70 hp:
Forward gear
backlash
Less than
0.09 mm (0.004 in)
0.09 – 0.28 mm
(0.004 – 0.011 in)
More than
0.28 mm (0.011 in)
Reverse gear
1. Install a propeller on the propeller shaft,
with the front facing backward, fit the
nut and tighten.
Nut (propeller):
5 Nm (0.5 m • kg, 3.6 ft • lb)
2. Slowly turn the drive shaft in and out
and read the dial gauge when the drive
shaft stops in each direction.
3. Determine the shim size according to
the chart.
50 hp:
Reverse gear
backlash
Less than
0.84 mm (0.033 in)
0.84 – 1.17 mm
(0.033 – 0.046 in)
More than
1.17 mm (0.046 in)
60, 70 hp:
Reverse gear
backlash
Less than
0.75 mm (0.033 in)
0.75 1.13 mm
–
(0.033 – 0.044 in)
More than
1.13 mm (0.044 in)
6-27
Decrease or increase
Thickness of shim to be
decreased (mm) = (0.19
– measurement) × 0.53
Decrease or increase
will be unnecessary
Thickness of shim to be
increased (mm) = (mea-
surement – 0.19) × 0.53
Decrease or increase
Thickness of shim to be
increased (mm) = (1.01 –
measurement) × 0.60
Decrease or increase will
be unnecessary
Thickness of shim to be
decreased (mm) = (mea-
surement – 1.01) × 0.60
Decrease or increase
Thickness of shim to be
increased (mm) = (0.94 –
measurement) × 0.53
Decrease or increase will
be unnecessary
Thickness of shim to be
decreased (mm) = (mea-
surement – 0.94) × 0.53
E