'T' AirDog /FASS Return Line 'T' into stock fuel return line

[ctd4stan]

Just a possible option... Instead of adding another bulk head fitting to the fuel canister / module (or directly onto the tank) for the AD 100 / FASS 95 return line, what about installing a "T" fitting into the existing stock fuel return line instead?



Looking at some of the "modified fuel canister" pictures (unless the tube was removed), it looks like the stock return connection just drops / sprays into the fuel canister (vs. a tube to return the fuel to the bottom of the canister).



I also thought about using the ‘auxiliary fitting’, but then I would need some sort of 90* compression fitting on that plastic stub vs. directly connecting the return line but with time it would bend and cause a kink in the fuel return line.



Pro's / Con's to the stock fuel return line ‘T’ approach?

 

[cerberusiam]

I think the reason that is not a good idea is the AD return pressure is higher than the stock system pressure. You would run the risk of back pressuring the stock fuel return from the injectors and CP3 possibly causing flow interruption and problems there.



To integrate those 2 I think you would need a larger return line fron the AD connection to the fuel module and a one way valve from the stock return to make sure is no back pressure.



At that point an another bulk head fitting in the cannister for the AD is probably your best and easiest solution.

 

[RBellah]

I was thinking the same T-the line way would work on the auxilary tank in the bed... . maybe? Let me know as a friend of mine is doing the same thing.

 

[ctd4stan]

To avoid the possible back pressure, since I will be installing a 'tank vent mod', I will use the stock filler vent line as the return line into the tank. I just put a few fittings together to make the custom splicer that I need.

 

[steved]

The fuel vent line won't work... they have a check valve or some other reason not to allow fuel to flow down them... I tried that with my auxiliary tank line, it did not work. I eventually (like a week later) had to fix it... I ended up drilling and tapping the FASS manifold for a NPT-to-hose barb fitting and everything works fine.



I also would not use the return lines because the volume from the AD/FASS is most likely more than the stock return lines could adequately handle.



Why are you not using the AD/FASS manifold into the tank's fill line?

 

[cerberusiam]

Yeah, they have a roll over valve that is one way, out. You will have to remove that and replumb with a bulk head fitting any way.



Doing that starts to get into questionable modifications on the fuel tank systems. Your choice but be advised unless you do it correctly you could leave yourself liable.

 

[ctd4stan]

Thank you steved & cerberusiam, I definitely appreciate the input before making the change. Maybe the fitting varies because member 53 Willy's used the vent return as the AD return.

Trying to manage the $$, I would be fine with changing out the stock bulk head fitting (I'll check it first). Has anyone replaced that stock fuel vent line bulk head fitting - any tips?

Otherwise, I'll have to drill another hole and install another bulk head fitting (i. e draw straw but used for the return).

 

[steved]

If I remember correctly, the initial FASS connection was to the return line, but it cause tank foaming issues, which is why they went to the fill line connection.

 

[Labonte18]

I dont know if this is the proper tread to post this question to, but I will try it. . I have a airdog installed on my 03 2500, is there a mod to rid the engine compartment of the stock fuel filter canister? I know it needs to be on there for the return line. Is there a way to remove it and add something to bypass it?



thanks Robert

 

[AMcCormick]

Have a look at GDP they have what you are looking for

 

[AHolt]

I have the GDP on mine, if you go with this remember to

seal the two elec plugs you pull from stock housing.

 

[Labonte18]

Who's that?

What does GDP stand for? I'm sorry i don't follow the vendors that close. .





thanks robert

 

[MartyK]

It Glacier Diesel Products.



Glacier Diesel Power - Product Detail

 

[Scrappy]

To avoid the possible back pressure, since I will be installing a 'tank vent mod', I will use the stock filler vent line as the return line into the tank. I just put a few fittings together to make the custom splicer that I need.

I did the exact same thing with my GDP walbro system and it worked great

The fuel vent line won't work... they have a check valve or some other reason not to allow fuel to flow down them... I tried that with my auxiliary tank line, it did not work. I eventually (like a week later) had to fix it... I ended up drilling and tapping the FASS manifold for a NPT-to-hose barb fitting and everything works fine.



I also would not use the return lines because the volume from the AD/FASS is most likely more than the stock return lines could adequately handle.



Why are you not using the AD/FASS manifold into the tank's fill line?

He is talking about the tank port that the fill/vent line was attached to that is capped with the vent relocation kit.



this way he does not need the manifold in the fill vent line.