TOHATSU MFS 25D Service Manual page 266

Lower Unit
6. Perform shim adjustment as necessary based on the
gauge value obtained. The table shows the relation
between dial gauge readings and shim adjustments.
1. Values in this table indicate dial gauge
readings obtained when using the special tool.
2. Change the gear engagement position and
measure the backlash again.
7. After the adjustment, remove the backlash measuring tool,
and turn the drive shaft while pulling it up to see if it turns
smoothly.
If not, reduce the shim thickness by 0.05 mm and adjust
the backlash again.
If the engagement of the bevel gear assy A and
bevel gear B is imperfect, they may produce
abnormal noise when turning the drive shaft
while pulling it up. In such case, reduce the shim
thickness by 0.05 mm.
Keep the following matters in mind when taking
the measurement.
• The shaft 1 securing the bevel gear assy
A is tightened so that, even if the drive shaft
is lightly turned, it will not turn more than the
backlash.
• The drive shaft bearing is secured only at the
pump case (lower). The clamp 9 should be
attached as close to the pump case (lower) as
possible.
• Although the measurement with dial gauge is
taken by rotating the drive shaft while lifting it
up with the gear case and dial gauge secured,
make sure play does not occur with other
parts (runout of the drive shaft, play between
the drive shaft and bearing), etc., during
measurement.
6-36
Adjusting shim amount
Gauge value (mm)
0.00 - 0.13
0.14 - 0.34
0.35 - 0.57
0.58 - 0.78
0.79 - 1.01
1.02 - 1.23
1.24 - 1.46
1.47 - 1.69
1.70 - 1.92
1.93 – 2.00
Type of Shim
Thickness
0.1 mm (0.0039 in)
0.15 mm (0.0059 in)
(mm)
-0.1
-0.05
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
Part No.
369-64081-1
369-64082-1
4st 25/30 2022