Yamaha F75F - Adjusting the Forward Gear Shim Thickness (T1)

Shimming
8-31
• If the original forward gear shims (T1) are
missing, install new shims with a combined
thickness of 0.72 mm.
• Do not reuse a shim if deformed or
scratched.
2. Install:
• Forward gear assembly
• Drive shaft
• Pin
ion
See “Installing the drive shaft” (8-15).
• Propeller shaft
housing assembly
See “Installing the propeller shaft housing
assembly” (8-16).
3. Check:
• Drive shaft
movement
Not smooth  Repeat from step (2).
4. Measure:
• Forward gear backlash
See step (3) in “Measuring the forward
gear backlash and reverse gear backlash
before disassembly” (8-23).
Out of specification  See “Adjusting the
forward gear shim thickness (T1)” (8-31).
Adjusting the forward gear shim thick-
ness (T1)
1. Remove:
• Tapere
d roller bearing outer race
• Forward gear shim
(T1)
2. Measure:
• Thickness
of original forward gear shim
(T1) in 2 places.
Do not reuse a shim if deformed or scratched.
3. Select:
• Forward gear
shim (T1)
a. Determine the forward gear shim (T1)
thickness adjustment using the “For-
ward gear shim (T1) selection chart”
according to
the backlash measure-
ment (BL1) from “Measuring the for-
ward gear backlash”. See “Forward
gear shim (T1) selection chart” (A-14).
• If the shim thickness adjustment value is pos-
itive, increase the current shim thickness by
that amount and, if the value is
negative, de-
crease the current shim thickness by that
amount.
• The gray-colo
red area on the selection chart
indicates the range of the specified backlash.
Shimming is not required if the measured
backlash is within the gray-colored area.
• The values fo
r the shim thickness adjust-
ments specified in the selection chart are in-
tended to obtain the median value within the
range for
the specified forward gear or re-
verse gear backlash.
• The table that follows th
e selection chart
shows the shim thickness adjustments for
the points marked on the chart.
Forward gear backlash
0.15–0.88 mm (0.0059–0.0346
in)