airdog 2
 

I have a 2005 f350 diesel I am running no cat or muffler, power pup, air raid air filter. Stock lift pump went bad. Which airdog would work well with my set up? What happens to the stock upper fuel filter if I install this set up? and where do I get just the upper filter if this set up remains

Basically the only thing that got bypassed on my ADII install was the high pressure fuel line going into and out of the HFCM. The fuel bowl and return line aren't touched. The ADII comes with a 2 micron filter (plus a water separator filter that's washable and resuable) and the secondary filter on the truck is 3 micron. If it's still good then just leave it alone. You can't buy it alone as it comes in the set, at least as far as I know. If you find a place to buy them separately then PLEASE let me know.

I just installed an AD2. My AD2 has an internal pressure regulator and an internal fuel return to the fuel tank. So here are the mods I did to my fuel system.

Since my AD2 has an internal presssure regulator, I had to neuter the OEM fuel pressure regulator. I removed the OEM spring and brass cup and reinstalled the cap.

Next I removed the return line fitting from the filter housing, drilled and tapped it for 1/4-20 threads about 1.5" down inside the fitting. Then I took a 1/4-20 set screw, put some Locktite on the threads and screwed it in. That sealed the return line. If this is NOT done, you will not have any fuel pressure to the motor.

Since the AD2 has a 2 micron filter, I removed the engine mounted 3 micron filter and the filter mounting stem. This MUST be done or the stem without a filter installed will shut off fuel to the motor. I figured why have another filter to increase fuel system pressure drop.

I then removed the Banjo Bolts (BB), removed and disgarded the check valve assemblies and drilled out all three holes to .200".

Using a fuel pressure gauge, I set may AD2 fuel pressure regulator to 70 psi.

Performance improvements after the AD2 and BB mods: lot better throttle response, more power when the go pedal is pushed and slightly better fuel mileage (16.2 to 17.1 hand calculated).

Remember, this procedure is for an AD2 w/ internal pressure regulator. If your AD2 does not have an internal pressure, you must retain the OEM fuel system.

Recommend, if you use the OEM system, that you install the new ford pressure regulator spring kit and do the BB mod.

DSMMH

My 2002 7.3 requires 60-70psi, Jason at Airdog says the new AD is set to 55 at the factory, I have mine turned all the way up and can only get 62psi so make sure you do not need more