Tech Tip: Failed Booster Seal Causes Master Cylinder Leaks

Tech Tip: Failed Booster Seal Causes Master Cylinder Leaks

Chronic master cylinder failure due to fluid leaking past secondary seal in the master cylinder bore could be caused by a defective master cylinder pushrod seal in the power brake booster allowing vacuum to draw fluid past secondary seal of the master cylinder. Replace both master cylinder and power brake unit ....

Problem: Vehicles equipped with power brake booster assemblies.

Cause: Chronic master cylinder failure due to fluid leaking past secondary seal in the master cylinder bore. A defective master cylinder pushrod seal in the power brake booster allowing vacuum to draw fluid past secondary seal of the master cylinder.

Solution: Replace both master cylinder and power brake unit.

Note: When replacing brake components, always flush entire brake system with approved brake fluid from a sealed container.

Tech Tip courtesy of Cardone.

For additional information on products offered by Cardone, visit www.cardone.com.

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