Bend back the edges of the protective cover and unscrew the bolts securing the caliper to the steering knuckle, remove the protective cover and hang the caliper on a technological hook, avoiding tension on the brake hoses.
Install on bolt 1 (figure 4-4) fastening the front wheel to the hub 2 device 3 with indicator 4. Rest the indicator leg against the protective casing of the front brake, having first screwed the extension onto the leg, and set the indicator scale to the "0" position.
Measure the total axial clearance in the front wheel hub bearings by turning the hub and moving it in the axial direction using your hands.
If the gap is less than 0.01 mm or more than 0.15 mm, adjust it.
Move the indicator leg away from the hub and unscrew the adjusting nut; the nut is discarded.
Figure 4-4. Measuring the axial clearance in the front wheel hub bearings:
1 - front wheel mounting bolt;
2 - wheel hub;
3 - fixture 67.7834-9540;
4 - ICH-10 indicator;
5 - hub adjusting nut;
6 - steering knuckle;
7 - Front brake protective cover.
If the gap is more than 0.15 mm, adjust it in the following order:
- tighten the new adjusting nut to 20 Nm (2.0 kgf·m), turning the hub in both directions to self-align the bearing rollers;
- loosen the adjusting nut and tighten it again to 7 Nm (0.7 kgf·m);
- make a mark on the washer B (figure 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 hub bearings. The clearance in the bearings after adjustment should be within 0.01 mm to 0.07 mm. Repeat the clearance adjustment if necessary.
- remove the device and lock the adjusting nut by pressing the holes on the nut neck into the grooves of the threaded part of the outer joint tailpiece of the drive.
Figure 4-5. Tightening and adjusting the front wheel hub bearings:
A - nut edge;
B - mark on the washer.
Install and secure the protective cover, brake caliper with pads to the steering knuckle in the reverse order of removal. Tightening torque of bolts is 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 car and tighten the wheel nuts. Tightening torque of the nuts is 85...95 Nm.