Bonneville V6-231 3.8L VIN 3 SFI (1988)
Vacuum Brake Booster: Description and Operation
Delco-Moraine Single Diaphragm Type
Description
Fig. 6 Delco-Moraine single diaphragm booster
This power brake unit uses a vacuum brake booster of the vacuum suspended type which utilizes engine intake manifold vacuum and atmospheric
pressure for its power.
The unit consists of a vacuum power section and a hydraulic master cylinder section. The vacuum power section contains a power piston with rolling
diaphragm mechanism and power piston return spring.
The control valve is made up of an air valve and floating vacuum control valve assembly. The reaction mechanism consists of a hydraulic piston,
reaction plate and a series of levers. The valve operating rod, which operates the air valve, projects from the power section and is connected to the
brake pedal linkage.