The master cylinder is of tandem design, having an anodized aluminum body and a glass reinforced nylon reservoir. If the cylinder bore is pitted or scratched, the body must be replaced as honing will remove the anodized surface. The reservoir is indexed to prevent incorrect installation and the cap diaphragms are slotted to allow internal pressure to equalize. A secondary outlet tube leading from the master cylinder is connected to the differential valve mounted underneath the master cylinder. The front part of the valve supplied the right rear and left front brakes. The rear portion supplied the right rear and left front. The rear portion of the valve is connect to the primary outlet tube of the master cylinder.
REMOVAL & INSTALLATION
See Figures 1, 2 and 3
- Disconnect the primary and secondary brake lines at the master cylinder. Tape or plug the ends of the lines.
- Remove the nuts attaching the master cylinder to the power brake booster.
- Wrap a rag around the brake line fitting holes, slide the master straight away from the booster and remove from the vehicle. take care not to spill any brake fluid on the finish. Flush off with water if any fluid is spilled.
- Bench bleed the master cylinder. For more details, refer to the bleeding procedure outlined in this section.
- Install the master cylinder over the mounting studs.
- After aligning the master cylinder pushrod and mounting studs, hold the cylinder in position and start the attaching nuts but do not tighten completely.
- Install the brake lines but do not tighten completely.
- After the brake lines are installed, tighten the cylinder mounting nuts fully and then the brake lines.
- Finish bleeding the brake system.
See Figures 4, 5, 6 and 7
The aluminum master cylinder cannot be rebuilt; service is limited to replacement.