TOHATSU BFT250A Service Manual page 494

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GEAR CASE (STANDARD ROTATION)
REVERSE BEVEL GEAR SHIM
Measure the bearing height (H) of a new ball bearing
(55 x 100 x 21 mm) [1] using a regular vernier caliper [2]
as shown, and record the measurement.
Calculate the tolerance using the measurement H
obtained in the previous step and the following formula.
Formula: Tolerance = H – 21.5
Example:
When measurement (H) is 21.45 mm (0.844 in):
Tolerance = 21.45 – 21.5 = –0.05
The tolerance is –0.05 mm (–0.002 in).
Remove the trim tab from the gear case (page 16-8).
Cross reference the engagement mark [1] located on
the trim tab installation part of the gear case [2] and the
tolerance, and refer to the reverse bevel gear shim
selection table to determine the required thickness of
the shim (Sr).
Reverse bevel gear shim selection table
Refer to page 16-38 for information on how to read the
shim selection table and shim combination.
Select the shims from the reverse bevel gear shims of
different thickness to obtain the required thickness (Sr)
by combining the shims.
Shim type table
Install the trim tab on the gear case (page 16-9).
After shim selection, inspect the reverse bevel gear
backlash (page 16-43).
16-40
–0.29
–
–0.25
A 0.40
B 0.45
C 0.50
D 0.55
E 0.60
F 0.65
Shim type Thickness
Shim A 0.10 mm
Shim B 0.15 mm
Shim C 0.30 mm
Shim D 0.50 mm
Calculation value
–0.25 –0.20
– –
–0.20 –0.15
0.35 0.30
0.40 0.35
0.45 0.40
0.50 0.45
0.55 0.50
0.60 0.55
[1]
[2]
[2]
[1]
–0.15 –0.10
– –
–0.10 –0.05
0.25 0.20
0.30 0.25
0.35 0.30
0.40 0.35
0.45 0.40
0.50 0.45
Unit: mm
–0.05
–
0
0.15
0.20
0.25
0.30
0.35
0.40