Brake Master Cylinder: Testing and Inspection

NOTE: These checks will not determine all master cylinder malfunctions.

1. Check for a cracked master cylinder casting or brake fluid around the master cylinder. Leaks are indicated even if there is only a drop of fluid. A damp condition is not abnormal.

2. Check for a binding pedal linkage. If this is satisfactory, disassemble the master cylinder and check for swollen or elongated primary piston seal(s). If swollen seals are found, substandard or contaminated brake fluid should be suspected. If contaminated, all components should be disassembled and cleaned, all rubber components should be replaced and all pipes flushed.