Adjustment Of The Driving Gear Bearings; Refitting The Differential Housing; Defining The Thickness Of The Drive Gear Shim; Making The Measurements To Define The Thickness Of The Drive Gear Shim - Lada Niva 4x4 Service Manual

Fig. 3-71. Defining the thickness of the drive gear shim:
1 - indicator; 2 - fixture A.95690; 3 - drive gear rear bearing; 4 - tool A.70184
In this case fit an adjusting ring with thickness of 3.05 mm.
Fit an adjusting ring of the necessary thickness on the driving
gear and press fit using tool A.70152 (fig. 3-74) the rear bearing
inner ring which was taken from tool A.70184. Fit the distance
sleeve.
ATTENTION. When repairing the rear axle reduction gear,
install a new distance sleeve, if the reduction gear casing,
the final drive gears or the driving gear bearings were
replaced. If these parts were not changed, the former dis-
tance sleeve can be used.
Fit the driving gear into the reduction gear casing and place
on it the front bearing inner ring, the oil deflector, sealing, the dri-
ving gear flange and washer. Screw a nut on the gear end and,
having locked the driving gear flange, tighten it (tightening torque
is specified below).

Adjustment of the driving gear bearings

To restrict the axial shifts of the driving gear under working
loads, it is very important to create the bearing preload within the
given limits. Tension is monitored by a dynamometer
02.7812.9501 (fig. 3-75), which measures the driving gear
moment of resistance to rotation.
The moment of resistance to rotation determines the tight-
ness of the bearing. It should be 157 - 196 N•cm (16 - 20 kgf•cm)
for new bearings, and 39.2 - 58.8 N•cm (4 - 6 kgf•cm) - for bear-
ings after mileage of 30 km and more.
The flange nut should be tightened to torque 118 - 255 N•m
(12 - 26 kgf•m), periodically checking with the dynamometer the
bearing`s moment of resistance to the rotation of the driving gear.
To check the resistance torque, fix the dynamometer on
sleeve 3 (fig. 3-76), place the torque limit indicator 2 (fig. 3-75) on
the scale division corresponding to 196 N•cm (20 kgf•cm), and
92
Fig. 3-72. Making the measurements to define the thickness of the drive
gear shim:
1 - tool A.70184; 2 - fixture A.95690 with indicator; a 1 and a 2 - distance from
tool end face to differential bearing journal
make a few turns clockwise with handle 4. During rotation of the
driving gear the movable indicator 1 should not pass indicator 2
and should show no less than 157 N•cm (16 kgf•cm).
If the moment of resistance to rotation is less than 157 N•cm
(16 kgf•cm), and for bearings after 30 km - 39.2 N•cm (4 kgf•cm),
tighten the driving gear flange nut (but do not exceed the rated
tightening torque) and check again the driving gear moment of
resistance to rotation.
If the moment of resistance to rotation has appeared to be
more than 196 N•cm (20 kgf•cm), and for run-in bearings 58.8
N•cm (6 kgf•cm), this will indicate excessive bearing preload.
Renew the deformed distance sleeve. After replacing the dis-
tance sleeve, re-assemble the unit with the appropriate adjust-
ments and checks.

Refitting the differential housing

Fit in the casing previously assembled differential housing
together with the outer bearing rings.
Place two adjusting nuts 4 (fig. 3-77) so that they adjoin the
bearing rings.
Fit the bearing covers and tighten the fastening bolts with a
torque wrench.