Note. Please read the warnings at the beginning of this section carefully Replacement of hoses and tubes of the hydraulic path of the brake system.
Status check
Note. Discs are always replaced in pairs for both brake mechanisms of a given axle in order to avoid loss of vehicle directional stability when braking.
1. Apply the parking brake, then jack up the front of the vehicle and place it on jack stands. Remove the corresponding front wheel.
2. Rotate the disc slowly and carefully inspect both sides for deep scratches, gouges, and gouges. Minor roughness can be ignored, but in case of detection of serious defects, the disc must be replaced.
3. It is normal to have rust spots and brake dust on the outer edge of the disc surface. If desired, the disc can simply be cleaned with sandpaper. If, however, a step has formed along the edge of the disc as a result of excessive wear of the working surface, the thickness of the disc should be checked using a micrometer. Measure at several points along the perimeter of the disc, both in the contact area with the brake pads and outside it. A disc worn below the permissible limit must be replaced.
4. Using a plunger-type dial gauge, or a flat metal bar and a blade-type feeler gauge, evaluate the amount of disc runout, making sure that it does not exceed the allowable value. The amount of runout is measured along a circle located 10.0 mm from the outer edge of the disc. If the measurement result is out of range, the disc must also be replaced, however, first make sure that the wheel bearing is in good condition.
5. Carefully inspect the rim for cracks, paying particular attention to the areas around the wheel bolt holes. Replace disc if defective (paired with the opposite).
Removing
1. Remove the two bolts securing the brake caliper anchor bracket to the hub assembly. Remove the caliper from the disc and tie it with wire to the suspension spring (try not to stretch the flexible brake hose).
2. Screw in the mounting screw and remove the brake disc from the hub assembly. If the disc is tight, tap it to release it with a soft-faced hammer.
Installation
1. Make sure that the mating surfaces of the disc and hub are absolutely clean during installation. When installing a new disc, remove all traces of preservative from it with solvent.
2. Install the disc on the hub and tighten the mounting screw to the required force.
3. Return the caliper assembly to its original place - make sure that the brake pads are placed correctly on both sides of the disc. Screw and tighten with the required effort fixing bolts.
4. Replace the wheel, lower the vehicle to the ground and tighten the wheel bolts to the correct torque. Squeeze the foot brake several times to shrink the pads on the disc, then you can start moving.