Belarus 80.1 Operation Manual page 313

6.4.4.14 Operation 45. Check and adjustment of axial preload in tapered bearings of
the pivot
Note – The operation shall be performed on tractors BELARUS-820.
To check and, if necessary, adjust the axial preload in tapered bearings 6 (Figure
6.4.37) of the pivot, carry out the following preparatory work:
- clean the FDA from dirt;
- put the tractor on a flat ground, stop the engine, brake it with a parking brake, lock
the rear wheels against spontaneous movement with wheel chocks at the front and back;
- jack up the front tractor part and install supports under the FDA in the intended
spots for the levelling jack;
- unscrew the wheel retaining nuts and remove the wheels while observing precau-
tions;
- detach the steering link from the left and right wheel gear groups and remove it
from the FDA;
- remove the pin that fastens the hydraulic cylinder from the bracket, attached to the
wheel gear group.
Check of axial preload in tapered bearings of the pivot shall be performed in the fol-
lowing order:
- with the help of a dynamometer, determine the steering force of each wheel gear
group, first to one side and then to the other. The force shall be applied to the wheel re-
taining bolts that are located closest to the reduction gear's horizontal axis.
- axial preload in bearings shall correspond to the turning force of reduction gear
from 60 to 80 N applied to the wheel-retaining bolts. Repeat the force check operation
three times in each direction to determine an average.
At turning force of 30 to 50 N, it is necessary to adjust the preload in pivot bearings
in the following order:
- check the tightening of bolts of lower axis 7 (it shall make from 180 to 200 N  m);
- unscrew bolts 4 (Figure 6.4.37) of upper axis fastening of the pivot 1;
- with the help of dismounting bolts lift up the upper axis 1, and remove adjusting
shims 5 of identical thickness from both sides of axle flange to reach the necessary pre-
load in bearings;
- tighten axis-fastening bolts 4 with a torque from 180 to 200 N  m; tighten them in a
criss-cross pattern and make sure to turn through the wheel gear group;
- re-check the preload in pivot bearings by checking the turning force of reduction
gear to both sides;
- repeat the listed operations for the second wheel gear group.
If the turning force is below 30 N, then before adjusting preload in bearings, it is
necessary to dismount the lower axis 7 (Figure 6.4.37) and check the lower bearing for
technical condition.
After adjusting, grease the bearings of wheel gear group. Remove protective cap 2
and inject the lubricant through grease fitting 3 in axes 1, 7.
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80-0000010B OM