Vacuum Brake Booster: Description and Operation

DESCRIPTION





The power brake booster (3) is mounted to the engine side of the dash panel. The master cylinder is bolted to the front of the booster. A vacuum check valve is also mounted on the front of the booster. A vacuum line connects the check valve to engine source vacuum. The booster input rod extends through the dash panel and connects to the brake pedal.

This vehicle uses a tandem diaphragm, single rate vacuum power brake booster with 203 and 229 mm (8 and 9 in.) diaphragms. Power brake boosters are internally tuned differently depending on whether the vehicle is equipped with ABS or without ABS. If the power brake booster requires replacement, be sure it is replaced with the correct part.

The power brake booster can be identified by the tag attached to the body of the booster. This tag contains the following information:

- The production part number
- The date it was built, and
- The booster manufacturer.