What is the purpose of a check valve on a brake booster?
What is the purpose of a check valve on a brake booster?
The brake booster check valve helps regulate the vacuum in the brake booster. When the engine is off or if the vacuum hose has a leak, the one-way check valve ensures no external air enters the vacuum brake booster.
Where is the brake booster check valve?
The brake booster check valve is typically found on the brake booster. If it is not found on the brake booster, it may be in line with the vacuum hose. There are many types of check valves, though, and some check valves are built into the vacuum hose and are not serviceable separately.
What is the purpose of a check valve in a hydraulic system?
Check valves are the simplest form of hydraulic devices in that they permit free oil flow in one direction and block oil flow in the opposite direction. Check valves may also be used as a directional or pressure control in a hydraulic system.
How do you check a vacuum booster check valve?
Vacuum Inlet Check Valve Test: To test the vacuum check valve, disconnect the vacuum supply hose from the intake manifold or vacuum pump, and blow into the hose. If air passes through the valve into the booster, the check valve is defective and should be replaced.
What happens when a brake booster check valve fails?
When the check valve is not working correctly, the operation of the brakes becomes much more difficult. Specifically, the pedal goes from smooth and soft to aggressive and very difficult to press down. This is due to the excess pressure inside the master cylinder, which the check valve is designed to regulate.
How do you check for a brake booster leak?
Turn the engine off, then repeatedly press the brake pedal slowly. When you pump it the first time the pedal should be very ‘low’— meaning not much pressure resistance. As you pump the pedal, the pressure should become firmer, which will indicate that the brake booster is not leaking.