303.02.0033.01 Repair Kit for 4-Circuit Protection Valves

What does a 4-circuit protection valve repair kit do?

A 4-circuit protection valve repair kit is a specialized overhaul set designed to renew the internal wear components of a four-circuit protection valve within a pneumatic brake system.

Compatible vehicles and systems

This kit is essential for maintaining the safety and reliability of heavy commercial vehicle braking systems. It works by renewing internal elements to ensure the valve can effectively distribute compressed air into independent circuits, such as front axle, rear axle, and parking brakes, while protecting against pressure loss in individual lines. This component is also sometimes referred to as a four-circuit safety valve or multi-circuit protection valve.

Installation and maintenance guidance

This repair kit is compatible with WABCO systems and is fitted to MAN, Scania, DAF, Alexander Dennis, Van Hool, and VDL vehicles. To ensure correct fitment, technicians should verify the manufacturer's part number on the existing valve housing to match circuit priority and connection dimensions.

Troubleshooting and selection

When performing maintenance, it is vital to inspect the diaphragm and springs to ensure they meet original specifications. Using high-strength components during the overhaul helps the valve return to its factory pressure values and response speed. Consult your authorized distributor for precise application details.

OE cross-reference

303.02.0033.01 (4-Circuit Protection Valve Repair Kit) is the equivalent of the WABCO OE number. This part directly replaces WABCO OE number 9347149252.