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Topic: Fass fuel filter system (Read 1734 times) previous topic - next topic

Re: Fass fuel filter system

Reply #20 –
Got the system installed and started up the coach today and the engine runs.
I cut a piece of 3/8 x 4 x 8 inches plate and bolted it to the frame so I could mount
the filter system. Then I bolted the system to the plate and it all worked out.
Hopefully Sunday night I will get to see if it makes any difference and the will post
my findings.

Re: Fass fuel filter system

Reply #21 –
Is there a reason not to Tee into the OEM return line downstream of a check valve? I installed a FASS pump (pump  only), but used a Davco 382 as the primary and the OEM engine mounted secondary and so did not have to add an extra return line, but I would have looked at using the the return line post fuel cooler if I had used the FASS filtration. That said, nice bung installation! ^.^d
Don
Quote from: dsd –
Understand there will be two fuel return lines. The original fuel return from the engine and a additional 3/8 line to return fuel line from the FASS with removed air back to the tank. This relieves all vacuum draw issues and prevents any possibility of air being drawn in. I would prefer to see the FASS system as close as possible to the tank. All excess fuel is returned to the tank going thru the ECM chilling plate then routed to the fuel cooler outside of the radiator and returned to the fuel tank.
Scott

Re: Fass fuel filter system

Reply #22 –
Don the FASS showed the secondary fuel return line separated and actually below the other return. I still dont see why you couldnt combine return lines. The generator and aqua hot also have separate return lines. I want to actually measure the aqua hot return, but suspect it is minimal. Easy access also. All very interesting. IMO slight positive fuel pressure would be better than a vacuum the U320 operates normally with. Looking forward to Peters results. I'm like within the last 7k or so of want to do mods, hopefully will end eventually

Re: Fass fuel filter system

Reply #23 –
Fass in there literature said not to tee into the existing return line as it could increase
the return line pressure and cause engine problems. The Fass system returns quite a
bit of fuel to the tank. I can here the fuel going back into the tank.

Re: Fass fuel filter system

Reply #24 –
Quote from: oldguy –
Fass in there literature said not to tee into the existing return line as it could increase
the return line pressure and cause engine problems. The Fass system returns quite a
bit of fuel to the tank. I can here the fuel going back into the tank.
Wonder if the entire return volume is increased? Would think it would be. Probably not a issue for you but running return threw a cooler would be beneficial to us desert dwellers

Re: Fass fuel filter system

Reply #25 –
Quote from: dsd –
Wonder if the entire return volume is increased? Would think it would be. Probably not a issue for you but running return threw a cooler would be beneficial to us desert dwellers https://tenor.com/view/esselcius-bonalkset-gif-21288908

Scott with your skill set a return bypass for the Fass could be teed off to the factory return line could be fabricated.

Re: Fass fuel filter system

Reply #26 –
Quote from: craneman –
Scott with your skill set a return bypass for the Fass could be teed off to the factory return line could be fabricated.
They are real clear they do not want to use engine return line. But our tanks do have three return lines. Engine, generator and aqua hot. Aqua hot shared return has my interest. 20/20 hind site I would of added a additional bung when I had the tank out. Also when they speak of a return they are using the overboard vent and dont want to have raw fuel pushed out the vent. Its also in the center of the tank and unreachable on my coach.

Re: Fass fuel filter system

Reply #27 –
On second thought just a fuel cooler on the Fass return.

Yup, that insures both cooler fuel and zero chance of back pressure on engine's fuel system.

Re: Fass fuel filter system

Reply #28 –
Quote from: craneman –
On second thought just a fuel cooler on the Fass return.

Yup, that insures both cooler fuel and zero chance of back pressure on engine's fuel system.
Yes could easily put in the front axle area between frame rails.

Re: Fass fuel filter system

Reply #29 –
I installed a FASS 165-gallon system on my 1999 8.3 and used the 1/2 line am getting high pressure at the pump 22-24 PSI, I disconnected the return line at the pump a ran a hose directly to a 5 gal bucket pressure dropped down to 19 psi so I think I will run a 5/8" return line instead of the 1/2" Have a return in the filler neck that have to be adapted to the 5/8" noticed that where the 1/2" goes into the filler neck it goes down to about 3/8"

Re: Fass fuel filter system

Reply #30 –
I have tried out the new system going to Whistler and I noticed a increase of turbo
pressure.