Loosen the bolt securing the brake hose to the caliper.
Loosen the caliper cylinder bolts.
Remove the cylinder and brake pads.
Pic. 6.25. Bolts of fastening of a support to a rotary fist
Loosen the bolts securing the caliper to the steering knuckle (pic. 6.25).
Remove the support.
Disassembly
Remove the piston boot.
Pic. 6.26. Removing the piston from the caliper
Press the piston out of the caliper with compressed air (pic. 6.26).
Pic. 6.27. Piston Seal Removal
Use a screwdriver to remove the piston seal from the caliper (pic. 6.27).
Note. Do not put your fingers between the piston and caliper.
Note. Be careful not to splash brake fluid.
Examination
Check the caliper for wear, cracks, rust in the piston holes.
Assess the condition of the pistons. Replace piston if worn or scored.
Check the condition of the bushing and pin.
Check for damage to the pad springs and piston boots.
Pic. 6.28. Measurement of brake disc thickness and runout
Measure the thickness and runout of the brake disc (pic. 6.28).
Attention! Do not restore the piston surface with sandpaper.
Attention! All rubber parts must not be reinstalled.
Brake Disc Thickness:
- Rated: 24 mm.
- Limit: 22.4 mm.
- Disc runout: 0.08 mm, no more.
- Brake disc thickness difference: 0.01mm.
Note. The brake disc thickness difference is determined by the difference between the minimum and maximum thicknesses measured at eight points along the circumference approximately 10 mm from the edge of the disc.
The runout of the disc is determined by a circle of 5 mm from the edge of the disc.
If repair is not possible, replace the brake disc.
Assembly
Rinse all parts (except pads and pad gaskets) isopropyl alcohol.
Lubricate the piston seal with special grease and install the seal in the groove of the caliper bore.
Pic. 6.29. Piston and boot
Install the piston and its boot (pic. 6.29).
Lubricate the caliper bore for the piston, the outer surface of the piston and the boot with special grease.
Pic. 6.30. Piston and anther installation diagram
Install the boot on the piston, as shown in Figure 6.30.
Insert the boot into the groove of the caliper hole, push the piston into the caliper.
Pic. 6.31. Scheme of assembly of the sliding parts of the caliper
Assemble the sliding parts of the caliper (pic. 6.31).
Lubricate the bushing, pin and caliper bore for the bushing with special grease. Lubricate also the anthers of the bushing and pin.
Install the boot into the groove in the caliper hole.
Install the brake pads.
Note. Do not allow grease to get on the pads and brake disc.
Note. Before tightening the bolts, make sure that the sliding pin and pilot bolt surfaces are not damaged.
Note. Bleed the brake system. Check for brake fluid leaks.