3116 and 3126 HEUI Truck Engines Fuel System – Prime

Prime the fuel system in order to fill the fuel filter and purge trapped air. The fuel system requires priming after:

* being run dry
* storage
* fuel filter replacement

Engines Equipped With A Fuel Priming Pump
1. Unlock and operate the priming pump until a resistance is felt. A considerable number of pump strokes may be required.

2. Push in and lock the priming pump.

3. Promptly start the engine. If the engine runs rough, continue to operate the engine at low idle until the engine operates smoothly.

NOTE: If the engine will not start, or once started, continues to misfire or smoke, further priming may be necessary.

Engines Not Equipped With A Fuel Priming Pump

(1) Plug. (2) Fuel filter.

If the engine is not equipped with a fuel priming pump, it may be necessary to fill the fuel filter with CLEAN fuel. The following procedure will allow only filtered fuel to enter the fuel system.

1. Remove plug (1) in order to fill fuel filter (2). Ensure that air is able to vent from the plug fitting while the fuel filter is being filled. Clean up any spilled fuel immediately. Clean plug (1). Install plug (1).
2. Start the engine and immediately increase the engine rpm to 1/2 of rated rpm.

3. Maintain the engine rpm until the engine operates smoothly.

4. Reduce the engine rpm to low idle.