Maverick and Comet Repair
BRAKES - MASTER CYLINDER OVERHAUL
Referring to the accompanying exploded view of the dual master cylinder components, disassemble the unit as follows: Clean the exterior of the cylinder and remove the filler cover and diaphragm. Any brake fluid remaining in the cylinder should be poured out and discarded. Remove the secondary piston stop bolt from the bottom of the cylinder and remove the bleed screw, if required. With the primary piston depressed, remove the snap-ring from its retaining groove at the rear of the cylinder bore. Withdraw the pushrod and the primary piston assembly from the bore.
NOTE:
Do not remove the screw that retains the primary return spring
retainer, return spring, primary cup and protector on the primary
piston. The assembly is adjusted at the factory and should not be
disassembled.
Remove the secondary piston assembly.
NOTE: Do not remove the outlet tube seats, outlet check valves and outlet check valve springs from the cylinder body.
All components should be cleaned in clean isopropyl alcohol or clean brake fluid and inspected for chipping, excessive wear and damage. Check to ensure that all recesses, openings and passageways are clear and free of foreign matter. Dirt and cleaning solvent may be removed by using compressed air. After cleaning, keep all parts on a clean surface. Inspect the cylinder bore for etching, pitting, scoring or rusting. If necessary, the cylinder bore may be honed to repair damage, but never to a diameter greater than the original diameter plus .003 in.
During the assembly operation, be sure to use all parts supplied with the master cylinder repair kit. With the exception of the master cylinder body, submerge all parts in extra heavy duty brake fluid. Carefully insert the complete secondary piston and return spring assembly into the cylinder bore and install the primary piston assembly into the bore. With the primary piston depressed, install the snap-ring into its groove in the cylinder bore. Install the pushrod, boot and retainer (if equipped), then install the pushrod assembly into the primary piston. Be sure that the retainer is properly seated and is holding the pushrod securely. Position the inner end of the pushrod boot (if equipped) in the master cylinder body retaining groove. Install the secondary piston stop bolt and O-ring at the bottom of the master cylinder body. Install the bleed screw (if equipped) and position the gasket on the master cylinder filler cover. Be sure that the gasket is securely seated. Install the cover and secure with the retainer.
