Differences in the various FASS pumps?

[wamcneil]

Hi all,

I'm trying an experiment with FASS system.

There's a seller on ebay closing out discontinued FASS model TSD11110G that is marketed for ram ecodiesel 3.0. It's cheap enough that I'm willing to experiment a bit. There's one left if anybody is interested. Asking price $295 and accepting offers.

Anyway, this is 110 gph @ 70 psi. Too much pressure.

I think/hope that the various fass "Titanium Signature Series" units are all basically the same and the 16-18 psi regulator spring (PS-1001) is all I need to bring the pressure down to suit the ISL CAPS system. Hopefully the regulator spring and installation kit are the only significant differences.

Fass lists various replacement motor/pump assemblies for the titanium series that appear to be permutations of two different motors with three gear reductions.

What do y'all think? Are there likely to be complications from altering a 70psi pump to output 16-18psi?

I figure that a positive displacement pump like this (vane?) will spin at the same speed and deliver the same volume, but have less work to do pushing against a lower output pressure.

 

[JDCrow]

I went with this unit as it took all the guess work out and kept the OEM filters in place.

 

https://www.ultrarvproducts.com/UP95G-Heavy-Duty-Lift-Pump-for-Cummins-ISC-ISL-CAPS-Fuel-System?search=8.3&description=true&page=2

[wamcneil]

Yeah, I've been vacillating between a pump like yours in the rear -vs- pump/filter "air separation system" up front. 

I'm not convinced that "air separation systems" are critically important or provide any measurable benefits beyond those of good filtration. Seems to me that just putting a pump in-line with the original filtration equipment would be a good solution.

The price is shocking though. Even for just the pump. Good grief, it's a simple DC motor with a pump head. The gross margins on these pumps must be obscene.  

Nevermind on the original question about pressure reduction... the ebay seller just contacted me to say they don't actually have the thing in stock anyway.

[jacwjames]

I installed the TSD08100G which is a 100 gph flow rate but it has an internal pressure regulator to limit pressure to ~16psi.

Not sure what the big difference is and whether the additional pressure would be a problem.  I'd be concerned with leaks down stream. 

You could consider putting in a pressure regulator with at return to tank on the excess.  I'm sure a work around is possible, just not sure what all is involved.  Working with higher pressure fuel might be an issue. 

 

 

[wamcneil]

2 minutes ago, jacwjames said:

I installed the TSD08100G which is a 100 gph flow rate but it has an internal pressure regulator to limit pressure to ~16psi.

Not sure what the big difference is and whether the additional pressure would be a problem.  I'd be concerned with leaks down stream. 

You could consider putting in a pressure regulator with at return to tank on the excess.  I'm sure a work around is possible, just not sure what all is involved.  Working with higher pressure fuel might be an issue. 

 

 

Moot point now... but the plan was to replace the 70psi regulator spring with 16-18psi regulator spring

"I think/hope that the various fass "Titanium Signature Series" units are all basically the same and the 16-18 psi regulator spring (PS-1001) is all I need to bring the pressure down to suit the ISL CAPS system."

Edited May 8 by wamcneil

[tmw188]

Call FASS