- Wheel bolt - 90 Nm
- Caliper guide bolt - 40 Nm
- Caliper mounting bolt - 100 Nm
Operating procedure:
- raise the front of the car and place supports under the body;
- remove the wheel from the desired side;
- with the help of a plastic film placed under the cover of the compensation tank, reduce the loss of fluid that is inevitable during work. It is permissible to pinch the hose extending from the compensation tank with a clamp;
Figure 7.3. Loosening the brake hose nut (arrow)
- clean the place of attachment of the brake hose to the caliper from dirt and loosen the nut (Figure 7.3);
- remove the brake pads as described above;
Figure 7.4. Bolts of fastening of a support to a rotary fist (arrows)
- unscrew the two bolts securing the caliper to the steering knuckle (Figure 7.4);
- completely unscrew the brake hose while turning the brake caliper, and not vice versa;
- check the condition of the hose and replace it if necessary;
- clean the caliper from dirt and corrosion products using a cleaning fluid for the brake system;
- remove the boot clamp with a thin-blade screwdriver;
- with compressed air (e.g. from a foot pump), connected to the brake hose hole, push the piston out of the cylinder. Pre-install a wooden block in the recess of the caliper in front of the piston so as not to damage the piston on the surface of the caliper. Remove the boot from the piston;
- carefully, preferably with a plastic tool, remove the sealing ring from the brake cylinder, being careful not to scratch the surface of the cylinder;
- press the guide bushings out of the caliper and remove their covers;
- using a special fluid for brake parts, thoroughly wash all parts. Do not use mineral solvents such as kerosene or gasoline for cleaning - they are aggressive for rubber parts of hydraulics. Dry parts immediately with compressed air or a lint-free cloth. Blow out the channels with compressed air;
- inspect the surfaces of the cylinder and piston. Scratches, corrosion, local wear are not allowed. Check the condition of the guide pins and corresponding bores in the caliper. The fingers should not be damaged, they should move easily in the bores, but not hang out in them. If in doubt, replace the failed parts;
- replace the brake cylinder o-ring, as well as all old anthers and seals;
- before assembly, make sure that all parts are absolutely clean and dry;
- immerse the piston and new seal in clean brake fluid, lubricate the inner surface of the cylinder with it;
- fit the piston seal into the cylinder groove by hand - tools can damage the seal. Install a new boot on the piston. Insert the piston into the cylinder. Gently press the piston into the cylinder, turning it slightly so that it enters without tilting. Fully press the piston into the cylinder so that the outer edge of the boot fits into the groove on the caliper;
- install the collar of the anther into the groove of the caliper;
- Apply grease from the repair kit or other suitable non-stick compound to the guide bushings. Install the bushings on the caliper;
- install new rubber boots, laying them in the grooves;
- screw the caliper onto the brake hose until it stops;
- install the caliper on the steering knuckle and screw in the two bolts of its fastening with the set torque;
- install the brake pads as described above;
- apply Loctite Frenblok to the threads of the guide pins;
- tighten the guide pins with new bolts to the specified torque, starting from the bottom pin;
- tighten the brake hose connection nut to the specified torque;
- install the brake pad wear sensor connector;
- remove the clamp from the expansion tank hose or remove the polyethylene seal (depending on what is used);
- remove the air from the brake circuit, which was worked on, as described below;
- install the wheel;
- lower the car;
- depress the brake pedal several times to bring the pads into position.