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Brake Master Cylinder




Brake System Inspection







Brake Master Cylinder

NOTE: During normal operation of the brake master cylinder, the fluid level in the brake master cylinder reservoir will fall during brake application and rise during release. The returning brake fluid creates a slight turbulence in the master cylinder reservoir. This is a normal condition and indicates that the compensator ports are not clogged. Clogged compensator ports may cause the brakes to hang up or not fully release. The net fluid level (such as after brake application and release) will remain unchanged. Fluid level will decrease with pad wear.

NOTE: A trace of brake fluid will exist on the booster shell below the master cylinder mounting flange. This results from the normal lubricating action of the master cylinder bore and seal.

1. Inspect the brake master cylinder for fluid leaks.
- Install a new master cylinder or brake fluid reservoir if signs of excessive leaking are present. For additional information, refer to Hydraulic System, Brakes &/or Brake Pedal Assy.

- To check for correct brake master cylinder operation, refer to Component Tests Component Tests and General Diagnostics.