See Figure 1
A preliminary check of the vacuum booster can be made as follows:
- Depress the brake pedal several times using normal pressure. Make sure that the pedal height does not vary.
- Hold the pedal in the depressed position and start the engine. The pedal should drop slightly.
- Hold the pedal in the above position and stop the engine. The pedal should stay in the depressed position for approximately 30 seconds.
- If the pedal does not drop when the engine is started or rises after the engine is stopped, the booster is not functioning properly.
- To test the check valve, disconnect the vacuum hose at the booster. Start the engine and let it idle, There should be vacuum available at the end of the hose. If there is no vacuum available, the check valve is faulty.
REMOVAL & INSTALLATION
- Disconnect the vacuum hose from the booster.
- Disconnect the brake lines from the master cylinder.
- Remove the brake pedal-to-booster link pin and the booster-to-fire wall nuts. The pushrod and nuts are located inside the vehicle on the driver's side, under the dash.
- Remove the booster with the master cylinder attached.
- Install the booster in position and tighten the mounting nuts to 9 ft. lbs. (13 Nm).
- Connect the vacuum hose to the booster and the fluid lines to the master cylinder. Tighten the fluid lines to 14 ft. lbs. (19 Nm).
- Bleed the brake system.