This picture is magnified X10 so you can even see the tiny hole used to bleed air from the system. Here is a close up of the bleed hole in the overflow valve.
Install valve through banjo fitting and into the pump.ģ. The other is located between the banjo fitting and end of the valve.Ģ. One gasket is located between pump and banjo fitting. The valve has no internally serviceable parts and must be replaced as an assembly. It connects the fuel return line (banjo fitting) to the pump. The overflow valve (pressure relief valve) is located at the outside of fuel injection pump. Remove valve from pump and banjo fitting. Clean area around overflow valve and fuel return line at injection pump before removal.Ģ. The other is located between the banjo fitting and end of the valve.ġ. The overflow valve has no internally serviceable parts and must be replaced as an assembly. Install overflow valve through banjo fitting and into Bosch VP44 injection pump.ġ0. Install new sealing gaskets to overflow valve.ĩ. Reduce regulated air pressure to 10 psi and observe overflow valve. The internal check valve should release, and air should pass through overflow valve at 97 kPa (14–16 psi).
Using blow gun, apply pressure to overflow valve inlet end ( the end that goes into Bosch VP44 injection pump).Ħ. Set regulated air pressure to approximately 97kPa (14–16 psi).ĥ. Remove overflow valve from Bosch VP44 injection pump and banjo fitting.Ĥ. Clean area around overflow valve and fuel return line at Bosch VP44 injection pump before removal.Ģ.
If a Diagnostic Trouble Code ( DTC) has been stored for “ P0168 decreased engine performance due to high injection pump fuel temperature”, the overflow valve may be stuck in closed position.Ī rubber tipped blow gun with regulated air line pressure is needed for this test.ġ. If the check valve within the assembly is sticking open, fuel drainage of the Bosch VP44 injection pump could cause hard starting. The valve opens at approximately 97 kPa (14 psi). Approximately 70% of supplied fuel is returned to the fuel tank. The overflow valve (a check valve) is used to route excess fuel through the fuel return line and back to the fuel tank. It is also used to connect the fuel return line (banjo fitting) to the Bosch VP44 injection pump for your Cummins powered Dodge truck.įuel volume from the fuel transfer (lift) pump will always provide more fuel than the fuel injection pump requires. The overflow valve is located on the side of the Bosch VP44 injection pump.