Vacuum Brake Booster: Description and Operation

The diaphragm-type power brake booster:
- is serf-contained.
- is mounted on the engine side of the dash panel.
- uses engine intake manifold vacuum and atmospheric pressure for its power.
- must be replaced with a new power brake booster if it becomes damaged or inoperative.
- utilizes a power brake booster check valve to provide temporary power assist when the vacuum source is reduced.

The power brake booster check valve and grommet are serviced separately. The hose is serviced as an assembly with the check valve. The power brake booster is serviced only as an assembly.