7.3 CalipersFig. 7-10 is an exploded view of the early-type rear disc brake caliper. The later type is very similar, the main differences being the locations of the parking brake actuator mechanism and the brake hose connection.
Brake fluid leaks around the brake caliper piston are the result of a failed or damaged piston seal, perhaps caused by corrosion, scoring, or pitting of the piston or caliper bore. The seal can be replaced, but a damaged piston, which is not available as a replacement part, will promptly destroy the new seal. To remedy a leaking caliper piston seal and avoid future problems, complete replacement of the caliper is recommended. A damaged caliper dust seal can be replaced separately. To replace a caliper, first disconnect the parking brake cable, as described in 7.2 Parking Brake (Disc Brakes). It may be necessary to loosen the cable adjusting nuts under the parking brake lever. Remove the two self-locking bolts which mount the caliper to the guide pins, and pull the caliper away from the pad carrier. (Hold the guide pins with an open-end wrench to remove the bolts). Disconnect the brake hose from the caliper and catch the brake fluid in a container. Cap the end of the brake line to prevent dirt and moisture from entering the brake system. Installation is the reverse of removal. Pre-bleed the caliper by laying it on its side, as shown in Fig. 7-11. Fill the piston chamber with brake fluid through the bleeder valve until clear fluid runs out of the brake hose connection, then close the bleeder valve. Torque the brake hose union to 15 Nm (11 ft. lb.). Use new self-locking bolts to mount the caliper to the brake pad carrier, and torque them to 35 Nm (26 ft. lb.). Bleed the brake system as described in 4.2 Bleeding Brakes.. Reconnect the parking brake cable and adjust it as described in Adjusting Parking Brake. Do not let brake fluid contaminate the brake pads or brake rotor surface.
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