Step-by-Step Installation Instructions

NOTE: Before beginning work, be sure vehicle is parked in a level area and that wheels are chocked to prevent unintentional movement.

1. Disconnect the ground cable from the battery. Vent any vacuum from the booster by applying the brakes several times. You will notice a change to a hard pedal when all vacuum has been vented.

2. Carefully disconnect hydraulic lines from the master cylinder.

3. Remove the nuts attaching the master cylinder to the power booster.

4. Separate the master cylinder from the booster mounting studs. Keep the master cylinder level.

DO NOT let brake fluid contact painted surfaces as the fluid will damage paint. Should fluid get on paint, immediately flush with water.

5. Disconnect vacuum hose(s) from the power booster.

6. Working under the instrument panel, disconnect the power booster rod linkage from the brake pedal.

Two-piece rods may have to be disassembled before the linkage can be removed from the vehicle.

7. Remove the nuts holding the power brake booster unit to the firewall.

The nuts may be located under the dash or on the engine side of the firewall.

8. Rotate the rod linkage if necessary and guide it through the firewall as you remove the power booster. Do not force the rod in either direction as this will damage the hub and reduce the booster’s core credit value.

9. Remove linkage parts from the original power booster for installation on the replacement unit.

Be sure to save any spacers or non-riveted mounting brackets since they must be reused when installing the replacement unit. These parts are critical to the operation of the replacement power booster.

10. Put the old power booster into carton to assure proper core credit upon return.


1. Install linkage from the old unit onto the replacement unit.
2. Important: Install spacers, gaskets and/or mounting brackets from the old unit onto the replacement unit.

3. Rotate the rod linkage as required to guide it through the firewall and position the replacement power booster. Do Not force the rod in either direction as this will damage the hub and void the warranty.

Two-piece rods may have to be reassembled after the replacement booster is installed in the vehicle.

4. Install and tighten the power booster mounting nuts.

5. Working under the instrument panel, connect the rod linkage to the brake pedal.

Pedal free play should be 1/16" to 1/4". Adjust pedal stop or stop light switch behind brake pedal if necessary.

6. Carefully locate the master cylinder onto the power booster mounting studs.

7. Install and tighten the master cylinder - to - booster mounting nuts.

8. Connect the vacuum hoses(s) to the power brake booster.

9. Connect hydraulic lines to the master cylinder with the fittings just snug. While an assistant applies moderate pressure to the brake pedal loosen one brake line fitting to let any trapped air bleed from the connection.

Then tighten the fitting before releasing the pedal. Wait 15 seconds and then repeat the process (including the 15 second delay) for each fitting on the master cylinder. Make sure the brake fluid reservoir is kept properly filled during and after this process.


Correct push rod length is essential to reliable braking. If the rod is too long, it causes the compensating ports in the master cylinder to be closed off, eventually resulting in brake drag.
If the push rod is too short there will be excessive brake pedal travel and possibly there will be a groaning noise from the brake booster. Use the following procedure to check the push rod adjustment.

Wear protective goggles when performing the following procedure! Brake fluid may erupt from the master cylinder with sufficient force to cause personal injury.

1. Remove the master cylinder reservoir cap or cover.

2. While an assistant slightly depresses the brake pedal, watch for fluid to erupt in the reservoir when the pedal is depressed 3/8" to 1/2". This indicates correct push rod length. On dual system master cylinder, fluid may spurt only from the front reservoir.

3. If the pedal travels more that 1/2" before master cylinder fluid erupts, the push rod is too short. If nothing happens no matter how far the pedal is depressed, the push rod is probably too long.

4. To adjust the push rod length, first remove the master cylinder from the power booster. Using a pair of pliers, turn the push rod adjusting nut in to shorten and out to lengthen the push rod.

5. If the push rod is non-adjustable, use shims between the master cylinder and power booster to shorten it. If too short, remove existing shims or remove the push rod from the booster and replace it with one of the proper length.

6. Install the master cylinder onto the power booster and recheck push rod length.

7. Connect the vacuum hose(s) to the power booster.

8. Reconnect the ground cable to the battery.

9. Make sure the braking system works correctly before moving the vehicle. If the pedal is soft or has excessive travel, it may be necessary to bleed the entire braking system.

Team ZR-1
True Custom Performance Tuning