Brake caliper
1, 10 - bracket; 2 - piston; 3 - seal; 4 - brake shoe; 5 - mounting pin; 6 - brake disc; 7 - heat-protective cap; 8 - retaining ring; 9 - anther
Removal the wheel brake mechanism
Front wheel brake mechanism
1 - brake disc; 2 - protective cover; 3 - steering knuckle; 4 - self-locking bolt; 5 - brake caliper; 6 - wire holder; 7 - bolt; 8 - connector; 9 - sensor mounting clamp; 10 - front wheel hub; 11 - self-locking bolt
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1. Prepare the vehicle and remove the desired front wheel.
2. Remove the brake pads (as stated earlier).
3. Unscrew the cap of the brake fluid reservoir of the master brake cylinder, place a gasket made of sheet polyethylene under it, screw the cap tightly in order to reduce fluid loss during further operations.
4. Unscrew the bolt securing the brake pad wear sensor from the caliper.
5. Loosen the brake hose connection on the brake caliper.
6. Unscrew the mounting bolts and remove the brake caliper from the steering knuckle, unscrew the union nut of the flexible hose.
7. To remove the rear wheel brake mechanism, the operations are carried out in a similar manner, only lift the rear of the car and remove the brake caliper from the wheel hub.
Disassembly
Control of the recess position
1. Remove the dust caps, but do not damage the pressed ring.
2. Using air pressure from a tire pump connected to the hydraulic inlet fitting on the brake caliper, push one of the pistons out while holding the opposite piston.
3. Blocking the hole of the removed piston (thick rubber), similarly push out the second piston.
4. Mark the pistons and corresponding cylinders to avoid confusion during assembly.
5. Perform a defect inspection of the piston and cylinder surfaces. The presence of scoring, seizure, and abrasions requires replacement of the entire brake caliper.
6. Remove the sealing rings from the cylinder grooves and install new sealing rings, cleaning them with clean brake fluid. The rings are installed manually.
7. Lubricate the pistons with brake fluid and insert them into the corresponding cylinders. Turn the pistons so that their recesses are at an angle of 20° relative to the bottom of the caliper and check their position with a template.
8. Push the pistons in as far as they will go and install the dust caps.
9. Press on the heat shield caps and make sure that the piston drive part protrudes at least 0.1 mm above the surface of the heat shield cap. The caps of the outer and inner pistons are different and are not interchangeable.
10. Installation is carried out in the reverse order of removal. Bleed air from the hydraulic drive.