Fuel Aeration Test and Bleeding

NOTICE: FORD DOES NOT PROVIDE A SPECIFIC PROCEDURE TO BLEED THE FUEL SYSTEM OF AIR.

Do not run your diesel vehicle out of fuel as this will allow air to enter the fuel system which will make restarting difficult. Longer engine cranking time may be required once air is in the fuel system. If air is allowed to enter the fuel system (during fuel change or if you run out of fuel) the engine will PURGE THE TRAPPED AIR AS IT RUNS. The engine may run rough and produce white smoke while air is in the system. This is normal and should correct it's self in short time.

WARNING: Do not crank the engine for more than 30 seconds at a time as damage to the starter motor may result.

If the engine fails to start in 30 seconds turn the key to the OFF position and wait 30 seconds before trying again.

10C. FUEL AERATION TEST

Purpose
To determine if the fuel is aerated and causing a poor idle condition.

Midship Fuel Tank Shown, Auxiliary Fuel Tank Similar:

Fuel Aeration Test
Install a clear hose on the fuel return line at the fuel conditioning module.

Run the engine at WOT for 2 minutes.

The return fuel should be free of bubbles.







1. Remove the fuel return line at the fuel conditioning module.
2. Attach a 1/4 inch diameter hose (clear) to the fuel conditioning module and place the other end of the hose into Rotunda Tool 034-00005 or equivalent.
3. Turn the key to the ON position. The fuel pump cycles on, then off. Diesel fuel may not flow out through the attached hose after only one key cycle. Repeat the key cycle until fuel flows from the attached hose.
4. Start the engine.
5. Run at WOT for 2 minutes. Return fuel should be free of bubbles.
6. If the fuel has air in it, the fuel returning to the tank appears white, foamy or non-transparent. If no or very little air is present in the fuel, the fuel will appears clear/transparent.
7. If air is present in the return fuel, inspect the fuel system for leaks.

Possible Causes:

NOTE: Air can enter the fuel system at any point where there is suction in the fuel system.

- Fuel pickup in the fuel tank.
- Fuel supply line entering the fuel module from the fuel tank.
- Fuel return line entering the fuel module from the engine.

Tools Required:
Rotunda Tool 034-00005 or equivalent