TOHATSU MD 70-90C2 Service Manual page 208

Lower Unit
Attach backlash measuring tool clamp w to drive shaft.
5.
Turn drive shaft q clockwise / counterclockwise slowly
6.
while pulling it up, and read change of dial gauge
indication.
When measuring, contact dial gauge tip to inside
of V groove located in the clamp ass'y.
Backlash Measuring Tool Clamp w :
P/N. 3B7-72720-0
Dial Gauge q :
Commercially Available Item
Magnetic Stand e :
Commercially Available Item
7. Select shim thickness required based on the change of
dial gauge indication and the table shown.
· Confirm dial gauge reading and adjust backlash
by using thickness of shim selected.
· Measure backlash several times while changing
gear teeth contact position.
· When measuring backlash, make drive shaft
pulling up force equal among the measurements.
· This work can be made easier when the
opening of gear case of propeller shaft side is
faced upward and fixed horizontally with a
holder.
Proper Backlash :
0.67 - 0.94 mm (0.0264 - 0.0370 in)
Add shim(s) into gap b between reverse (C) gear t and
8.
bearing y if necessary.
For removal or installation of reverse (C)
gear, refer to;
"Disassembly of Propeller Shaft Housing
Ass'y" or "Assembly of Lower Unit" in
Chapter 6 respectively.
Type of Shims :
0.1 mm (0.0039 in) P/N. 3B7-64037-0
0.15 mm (0.0059 in) P/N. 3B7-64036-0
6-38
CAUTION
r
q
Dial Gauge Reading : mm (in)
0.40∼0.54 （0.0157∼0.0213）
0.55∼0.66 （0.0217∼0.0260）
（0.0264∼0.0370）
0.67∼0.94
（0.0374∼0.0417）
0.95∼1.06
1.07∼1.24 （0.0421∼0.0488）
1.25∼1.41 （0.0492∼0.0555）
（0.0559∼0.0626）
1.42∼1.59
（0.0630∼0.0697）
1.60∼1.77
1.78∼1.94 （0.0701∼0.0764）
1.95∼2.12 （0.0768∼0.0835）
（0.0839∼0.0906）
2.13∼2.30
（0.0909∼0.0972）
2.31∼2.47
2.48∼2.65 （0.0976∼0.1043）
b
y
t
e
0¡
w
Shim Thickness : mm (in )
+ means addition of shim/-
means removal of shim
−0.10 （0.0039）
−0.05 （0.0019）
0.00
＋0.05 （0.0019）
＋0.10 （0.0039）
＋0.15 （0.0059）
＋0.20 （0.0078）
＋0.25 （0.0098）
＋0.30 （0.0118）
＋0.35 （0.0137）
＋0.40 （0.0157）
＋0.45 （0.0177）
＋0.50 （0.0196）
TLDI 75/90C2 2010