Bend the edges of the protective casing and unscrew the bolts securing the caliper to the steering knuckle, remove the protective casing and hang the caliper on the technological hook, avoiding tension on the brake hoses.
Install on bolt 1 (fig.4-4) fixing the front wheel on the hub 2 fixture 3 with indicator 4. Put the indicator leg into the protective cover of the front brake, having previously screwed the extension onto the leg, and set the indicator scale to the position "0".
Measure the total axial clearance in the front wheel hub bearings by turning the hub and moving it axially by hand.
If the gap is less than 0.01 mm or more than 0.15 mm, adjust it.
Take the indicator leg away from the hub and unscrew the adjusting nut, the nut is discarded.
Pic. 4-4. Measurement of axial clearance in the front wheel hub bearings:
1 - a bolt of fastening of a forward wheel;
2 - wheel hub;
3 - fixture 67.7834-9540;
4 - indicator ICh-10;
5 - adjusting nut of the hub;
6 - rotary fist;
7 - protective cover of the front brake.
If the gap is greater than 0.15 mm, adjust it in the following order:
- tighten the new adjusting nut to 20 Nm (from 2.0 kgf·m), by turning the hub in both directions to self-align the bearing rollers;
- loosen the adjusting nut and tighten again to 7 Nm (0.7 kgf·m);
- make a mark on washer B (pic. 4-5), then unscrew the nut by 20°-25°so that the edge A of the nut coincides with the mark B;
- check the axial clearance in the front wheel bearings. The clearance in the bearings after adjustment should be between 0.01 mm and 0.07 mm. Repeat the gap adjustment if necessary.
- remove the tool and lock the adjusting nut by pushing the holes in the neck of the nut into the grooves in the threaded part of the actuator outer joint shank.
Pic. 4-5. Tightening and adjusting the front wheel bearings:
A - the edge of the nut;
B - mark on the puck.
Install and secure to the steering knuckle the protective cover, brake caliper with pads in the reverse order of removal. Bolt tightening torque - 30... 35 Nm (from 3.0...3.5 kgf·m). Lock the bolts by bending the edges of the protective cover on the edge of the bolt head.
Install the hub caps, wheel and tighten the wheel nuts without tightening. Lower the vehicle and tighten the wheel nuts. The tightening torque of the nuts is 85... 95 Nm.