Big Father, Small Father at AMC Theatres-River East 21 This Weekend, Oct 16, 2015 (Friday) Festival event in Chicago, IL USA Big Father, Small Father October 16, 2015 at AMC Theatres-River East 21 in Chicago, IL 9:45PM.ind things to do this weekend in Illinois and other fun things to do.
In much the same way that vacuum boosters work, hydraulic power brake boosters rely on a pressure differential to provide braking assistance. The main difference is that it is hydraulic pressure that does the work rather than a vacuum-actuated servo.
A brake booster needs the right amount of vacuum to operate correctly. This is typically engine manifold vacuum (17-21Hg). On some engines, particularly diesels, an auxiliary pump is used to create vacuum. This vacuum is applied to both sides of the booster. Both the pedal side and the master cylinder side. As the driver presses the brake pedal, the vacuum valve blocks the vacuum source located on the pedal side of the booster. At the same time the air valve moves allowing atmospheric pressure in.