I have a question about the FASS system. I have a 2001 dodge cummins I just recenty installed a 150 GPH FASS system, 1/2 draw tube, and Big line kit. Im getting so much pressure in my tank that its blowing pressure out my fuel cap around the oring. What could be causing this and how could it be fixed. Its never done it before an just started after the installation. Any help I would appreciate.
Thanks Chad

 

It sounds to me like your vent tube is blocked. The FASS returns the air/foam back to the filler neck, and if the vent isn't working it may build up pressure and push it out the filler cap. I don't know this for sure but I am guessing. I do know don't try to fill it up with the truck running unles ou enjoy diesel baths. Don't ask how I know. Hope this helps.
Joe

 

Ok thanks I will check the vent out and let you know how it goes.

 

This prob was fixed about 2 years ago. Every kit now will allow the tank to be filled with the truck running.

I would check tank vent function. Something is not right here. ALSO is the return manifold pointed down stream? Its set at an angle to push fuel down the tube into the tank. If it was reversed, it could spray up to the fill cap area. Review our instructions and see if its positioned correctly.

http://www.dieselpp.com/billcook/FAS...l%20Manual.pdf

 

just curious and off topic...but what FP are you seeing?

i only see 13 idle, and 9 WOT with my FASS...i might as well run stock lift pumps, and just replace them every 6 months to get better pressure than this FASS gives me. 1/2" lines or not, i should see more than 13.

 

Thats all you need!! Is your fuel gauge correct? How much psi do you want? 14 psi is all you need. You won't have to replace the FASS every 6 months.

 

I checked the vents thier fine. Im getting ALOT of pressure in my return line. I dont have a fuel pressure gauge in the truck just the warning light indicator. I also just installed a schied diesel lighting vp44 injection pump dont know if that could have anything to do with it or not. Anyone ever had any problems with them?

 

If the vents fine the pressure would be blowing out the vent on top of the tank. Maybe you have a line on the wrong place.

 

Everything is hooked up like it should be. Im stumped could the injection pump have anything to do with it? I just installed a schied diesel hotrod pump at the same time.

 

If you want 19-21 PSI....Order a PS-1020 spring from any FASS dealer.......BUT like stated...you dont need it.......

Mine only drops 1.5PSI under WOT...might make sure you gague is 100% correct and that you dont have any restricitons on the suction side of the pump.

 

I dont see how the injection pump can cause this issue......heck..i dont see how the FASS could cause this issue as well. Its takeing out more than what its putting back....really.....Other than what i said before....its got to have something to do with the vents if pressure is building in the tank...not much else it could be.

 

The one guy I talked to said the injection pump might possibly be putting the high pressure fuel in the return line. But he wasnt sure. I called scheid about this and their sussposed to get back with me. I will let you know what they say. This problem didnt start right away it came after about a day of running the truck. So something must have happened in that period of time.

 

Do you only notice the fuel at the cap when your truck is full? Or anytime?

 

Its anytime full or not. We took the vent off the top of the tank and when you stick your finger over the vent hole on the tank within a sec you have lots of pressure. Its just building too much pressure for the vent to handle. Need to figure out were all the pressure is coming from. Everything is hooked up right im postive. Im getting so much pressure in the return line its actually creating a mist effect in the filler neck. As if pressure was behind it.

 

i had the same problem a couple years ago but it was because i had an injector problem. when i installed the new injectors the washer for the back injector wasent in right,(i didnt know it) i forced the injector in and then had a mist of fuel coming out of my fuel cap from compression. i dont know if you changed injectors or not but i figured id throw it out there.