Community Forums

camping fam · 05-11-2021, 05:18 PM

So lately it seems everyone is adding a FASS or AirDog my question is if you have already done this would you do the system or would you do your own filter and pump setup?

bubby124 · 05-11-2021, 07:18 PM

In my case I added the fass as insurance was it necessary, well I'll never knowm but I do know my caps system will never fail because of lack of fuel

MoePo · 05-12-2021, 06:11 AM

I went with airdog. Access to the top of my fuel tank is impossible to run a return line. Airdog allows you to tap into your fuel systems existing return line as the air dog doesn’t return the rate of fuel as the fass. My lift pump was leaking badly upon start up. So I went ahead and bypassed it. Deleted my stock fuel filter and put the air dog system in its place. Coach idles a hell of a lot better. And pulls grades easier.

jacwjames · 05-12-2021, 07:54 AM

After looking at the various installs of both the FASS and Airdog I decided to go with the FASS. On my coach I had enough room to mount near the fuel tank making the Return To Tank line easy to run along with the Tank line, and then using the existing fuel line from the FASS pump. Also, the stock wiring harness was an easy install in my front drivers side run bay, I was able to pick an ignition source and chassis battery source there to make for a clean install. I liked the idea of pumping & filter fuel back to tank for polishing.

Could have done something else but I decided if I was going to do it I wouldn't cut any corners.

I have the fittings and relay on order to bypass the OEM lift pump. Mine started to leak late last year, I tightened the 3 bolts but I know this was a short term fix.

I also have parts on order to install a fuel pressure gauge, seems logical to be able to monitor the fuel pressure to the CAPS since I'm doing the FASS install.

Lowflyer1 · 05-13-2021, 05:53 AM

Quote:

Originally Posted by MoePo

I went with airdog. Access to the top of my fuel tank is impossible to run a return line. Airdog allows you to tap into your fuel systems existing return line as the air dog doesn’t return the rate of fuel as the fass. My lift pump was leaking badly upon start up. So I went ahead and bypassed it. Deleted my stock fuel filter and put the air dog system in its place. Coach idles a hell of a lot better. And pulls grades easier.

That's the setup I've been thinking too although I have not been able to determine all the fuel lines coming and going yet. Probably need to remove the starter just to investigate further.

How did you tap into the return line, right at the lift pump?

MoePo · 05-13-2021, 06:28 AM

Quote:

Originally Posted by Lowflyer1

That's the setup I've been thinking too although I have not been able to determine all the fuel lines coming and going yet. Probably need to remove the starter just to investigate further.

How did you tap into the return line, right at the lift pump?

Yes T into the return line right before the lift pump.

camping fam · 05-15-2021, 09:41 PM

Put on my Airdog installed it next to my tank ran the return line into the tank, left the Cummins lift pump in place I had already replaced it twice not because it stopped but just out of safety to make sure it did not go bad. I should of done this 2 pumps ago!

My moho used the rock catcher as Freightliner called it above the rear axle I did remove that as it was no longer needed because of the airdog and it having 2 filters. I also left the big filter at the back as that was just more work to remove and an extra filter is no big deal plus already had my fuel pressure gauge setup on the output which heads straight to the $$$ pump!

At Idle I am getting 28-30 psi have not driven it yet and will if the pressure doesn’t go down I will adjust the pump accordingly.

As some of you guys know I did a big right up several years back about the rock catcher filter I wish I would of listened to my gut and went for this mod then but hind sight is 20/20

After ai drive it and do some more adjustments I will update.