Brake booster vacuum pump: replacement and selection

When and why it is necessary to replace brake booster vacuum pump

The brake booster vacuum pump has no specified lifetime limit and should be replaced if the diaphragm is broken or valves lost operability. Incorrect operation of the brake vacuum pump can be suspected if more effort is needed to be applied for pressing the brake pedal, while efficiency of the brakes decreased.

Replacement of a defective vacuum pump should be performed only at a service station, as works with the brake system require high qualification. The plunger pump is replaced together with gasket.

How to select brake booster vacuum pump

According to operation principle there are impeller pumps and plunger pumps. According to drive type there are components with electric drive, belt drive from the crankshaft pulley and ones installed directly onto the camshaft. The latter are especially sensitive to oil quality.

The pumps which have drive from the crankshaft or installed directly onto the camshaft, operate constantly at turned on engine and switch off only after the engine shuts off. After this, brake pedal pressing becomes hard, which may trouble, for example, towing of a broken car with the mechanical vacuum pump, if the engine can not be turned on due to some reasons.

The electric vacuum pump operates while ignition is turned on, that is why, on the cars, equipped with this unit, stiffness of the brake pedal does not depend on engine operation. In addition, such pump requires no supply and oil removal. Disadvantage of this component type is constant consumption of electricity, which affects speed of battery wear-out.

Road safety depends on serviceability of the braking system, that is why, buying the vacuum pump, you should give preference to manufacturers which produce high-quality components. Such companies as Pierburg, Topran, Vaico and others have proven credibility.

The vacuum pump should be selected strictly for a specific car model. This presupposes its construction, drive type, fastening type and other characteristics.