OVERHAUL

1972–84 Vehicles

1. Remove the master cylinder.
2. Drain the fluid. On models through 1976, remove the reservoir.
3. Remove the reservoir grommets from the master cylinder body on models through 1976 or elbow connectors on 1977–84 models.
4. Remove the dust boot.
5. Depress the piston and remove the piston stop ring from the cylinder.
6. Remove the piston stop washer, primary piston, and spring.
7. Loosen, but do not remove, the secondary piston stop screw.
8. Push the secondary piston inward, then remove the stop screw. Insert a guide pin in its place, and remove the secondary piston.
9. Remove the outlet port fittings, check valves and springs.
10. Clean all parts in clean brake fluid.
11. Inspect all parts for wear or damage. Replace any worn, discolored, misshapen or suspect part. The cylinder bore may be honed to remove light scoring, pitting or discoloration. If honing cannot polish the interior, discard the cylinder. Check the piston-to-bore clearance. If the clearance exceeds 0.15mm (0.0059 in.), replace the cylinder.
12. Assembly is the reverse of disassembly. Coat all parts in clean brake fluid before assembly. Use the guide pin to aid in installing the secondary piston. Refill the master cylinder and pump the piston several times, until fluid flows from each outlet port.

1986 Vehicles

1. Rock the reservoir from side-to-side to remove it from the master cylinder.
2. Remove the reservoir grommets.
3. Remove the piston stopper screw from the bottom of the master cylinder.
4. Depress the piston and remove the snapring.
5. Remove the primary piston assembly.
6. Remove the secondary piston assembly. Compressed air applied to the rearmost fluid port may be necessary to remove the secondary piston. If so, place a heavy rag over the cylinder bore to catch the piston.
7. Clean all parts in clean brake fluid.
8. Inspect all parts for wear or damage. Replace any worn, discolored, misshapen or suspect part. The cylinder bore may be honed to remove light scoring, pitting or discoloration. If honing cannot polish the interior, discard the cylinder. Check the piston-to-bore clearance. If the clearance exceeds 0.12mm (0.0047 in.), replace the cylinder.