Understanding Hydraulic Brake System Leaks

What causes hydraulic brake system leaks?

Technician A says most internal leaks are actually fluid bypassing the cups in the master cylinder. Technician B says that if the cups lose their ability to seal the pistons, brake fluid leaks past the cups and the pistons cannot develop system pressure. Who is correct?

Answer:

Technician B is correct.

Technician B is correct when it comes to identifying the cause of hydraulic brake system leaks. In a hydraulic brake system, internal leaks occur when brake fluid bypasses the cups in the master cylinder. If the cups lose their ability to seal the pistons, brake fluid will leak past the cups, and the pistons will not be able to develop system pressure.

This leakage can result in a loss of braking power and poses a potential safety concern for the driver and passengers. It is crucial to address any internal leaks promptly to maintain the effectiveness of the brake system and ensure safe driving conditions.