#75416, "RE: put a check valve in your brake booster line!" In response to In response to 15
Originally posted by micyek correct me if I wrong...but doesn't the booster "store" vacuum..therefore already has a check valve built in
I guess?is there a purpose to even add it?
Vacuum From The Engine
Engine intake manifold vacuum is used for augmenting the foot's braking power in vacuum assisted power brakes. This vacuum is created by the pistons as they draw downward, sucking air into the cylinders. When you push the brake pedal down, the vacuum control valve lets the engine draw a vacuum in the front section of the booster unit. The atmospheric pressure on the other side of the diaphragm provides significant additional braking force.
In a vacuum booster type system, pressure on the brake pedal pushes forward a pushrod connected to the pistons within the master cylinder. At the same time, the pushrod opens the vacuum-control valve so that it closes the vacuum port and seals off the forward half of the booster unit. The engine vacuum line then creates a low-pressure vacuum chamber. Atmospheric pressure in the control chamber then pushes against the diaphragm. The pressure on the diaphragm forces it forward, supplying pressure on the master cylinder pistons.