Yamaha F115A Service Manual page 434

LOWR
BACKLASH (REGULAR ROTATION MODELS)
6970
(3) Install the backlash indicator onto the
drive shaft (on the 22.4 mm (0.88 in)
diameter portion of the drive shaft).
Backlash indicator .................... 5
YB-06265 / 90890-06706
(4) Install the dial gauge onto the lower
unit and have the dial gauge plunger
contact the mark on the backlash indi-
cator.
Magnetic base attaching
plate ........................................... 6
YB-07003 / 90890-07003
Dial gauge set ........................... 7
YU-03097 / 90890-01252
Magnetic base........................... 8
YU-34481 / 90890-06705
(5) Set the lower unit upside down.
(6) Slowly turn the drive shaft clockwise
and counterclockwise. When the drive
shaft stops in each direction, measure
the backlash.
2. Adjust:
• Forward gear shim
Remove or add shim(s).
Forward gear
backlash
Less than
0.19 mm (0.007 in)
More than
0.53 mm (0.021 in)
M: Measurement
MEASURING THE REVERSE GEAR
BACKLASH
1. Measure:
• Reverse gear backlash
Out of specification → Adjust.
Reverse gear backlash
0.86 - 1.26 mm (0.034 - 0.050 in)
6-67
E
Shim thickness
To be decreased by
(0.36 – M) × 0.58
To be increased by
(M – 0.36) × 0.58
6