Yamaha F50F Service Manual page 194

LOWR
4. Install the backlash indicator onto the
drive shaft (18 mm [0.71 in] in diameter),
then the dial gauge onto the lower unit.
NOTE:
Install the dial gauge so that the plunger a
contacts the mark b on the backlash indica-
tor.
Backlash indicator 4: 90890-06706
Magnet base plate 5: 90890-07003
Dial gauge set 6: 90890-01252
Magnet base B 7: 90890-06844
5. Slowly turn the drive shaft clockwise and
counterclockwise and measure the back-
lash when the drive shaft stops in each
direction.
Forward gear backlash:
0.09–0.62 mm (0.0035–0.0244 in)
6. Add or remove shims if out of specifica-
tion.
Forward gear
backlash
Less than
0.09 mm (0.0035 in)
More than
0.62 mm (0.0244 in)
M: Measurement
6-51
Lower unit
Shim thickness
To be decreased by
(0.36 – M) × 0.53
To be increased by
(M – 0.36) × 0.53
Available shim thicknesses:
0.10, 0.12, 0.15, 0.18, 0.30, 0.40, and
0.50 mm
7. Remove the special service tools from
the propeller shaft, and then install the
water pump assembly.
6C13G11