A car master cylinder has different types of ports, and each plays a specific role in moving brake fluid and building hydraulic pressure:
• Inlet Port (Replenishment Port): Connects the brake fluid reservoir to the cylinder bore, allowing fluid to flow in and keep the chamber full.
• Compensating Port (Vent Port): Allows fluid to flow back and forth between the reservoir and the compression chamber. It relieves pressure when brakes are released and lets extra fluid enter or leave as brake pads wear down.
• Outlet Ports: The threaded exit ports where high-pressure brake fluid leaves the master cylinder and travels through the brake lines to the wheels (calipers or wheel cylinders).
• Breather Port / Air Vent: Located on the reservoir cap or body to maintain atmospheric pressure and prevent a vacuum from