98.5-02 Fuel System Troubleshooting

Engine won’t start:

Bleed the air out of the system

If you are starting your Cummins for the first time, it is helpful to “bleed” the air out of the injector lines by loosening the injector line nut just enough to allow fuel and air to escape the line while you are cranking the engine. It is usually required to do at least 3 injector lines. Tightening the line nut while you are still cranking the engine is the best way. This is also a good way to verify that the injector pump’s shut down solenoid is allowing fuel to the injector. If your supply fuel line is loose, it is possible to draw air into the fuel system at that point, so if you suspect you are not getting rid of the air in the system check your supply line connections. These engines should have between 7-15 psi of lift pump fuel pressure (higher pressures can cause serious damage to the injector pump). We have banjo bolts available that allow you to connect

94-98 Fuel system troubleshooting

Engine won’t start:

Bleed the air out of the system

If you are starting your Cummins for the first time, it is required to “bleed” the air out of the injector lines by loosening the injector line nut just enough to allow fuel and air to escape the line while you are cranking the engine. It is usually required to do at least 3 injector lines. Tightening the line nut while you are still cranking the engine is the best way. This is also a good way to verify that the injector pump’s shut down solenoid is allowing fuel to the injector. If your supply fuel line is loose, it is possible to draw air into the fuel system at that point, so if you suspect you are not getting rid of the air in the system check your supply line connections. These engines should have between 18-30 psi or more of lift pump fuel pressure. 

Good supply pressure/fuel at injector

If you have fuel at the injector, good fu