21697342 Volvo FH12 D12D Overflow Valve

What does an overflow valve do?

The injector pump overflow valve is a critical control component that maintains constant internal pump pressure by redirecting excess fuel back to the return line. This regulation is essential for ensuring stable engine idling and consistent power delivery in heavy commercial vehicles.

Compatible vehicles and engines

This specific part is compatible with Volvo FH12 trucks equipped with D12D engines. It serves as a reliable replacement for components in the fuel system, helping to prevent issues like increased fuel consumption or loss of engine power caused by pressure imbalances.

Installation and maintenance

Installation should be performed by a workshop technician to ensure no air or contaminants enter the fuel system. When installing this M10x1 thread valve, it is vital to ensure the system is properly bled of air to maintain correct operating pressures and prevent engine misfires.

Selection guidance

To ensure correct fitment, technicians should verify that the thread size and opening pressure match the requirements of the existing injection pump. Maintaining this component helps prevent long-term damage to the fuel injection system.

OE cross-reference

0103 064 (Injector Pump Overflow Valve) is the equivalent of the Volvo OE number. This part directly replaces Volvo OE number 21697342.