Critical Brakes
Master Cylinder and Servo Failure
Symptoms
Spongy or long brake pedal travel, brakes feel weak or unresponsive, brake fluid leaks inside the cabin or at the master cylinder.
Cause
The dual-circuit master cylinder has seals that perish with age. The servo diaphragm can fail, causing loss of brake assist. Contaminated brake fluid accelerates wear.
Fix
Rebuild or replace the master cylinder.
If the servo is faulty (check by pressing the brake pedal with the engine off, then start the engine, pedal should drop noticeably), replace or recondition it.
Bleed the entire brake system thoroughly using fresh DOT 4 fluid.
Never reuse old brake fluid.
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