dsl21

Hey guys,I have a 150gph fass pump on my truck.Its just the pump,not the filters,and its one of the first ones they sold.Is there a way to turn up the presure?I get 11 to 12 at idle and 5 to 6 at wot thanks

pickupman96

I bought the ball and spring for like 15 bucks and brought it up to 20 all the time

dsl21

where did you get it ? is that to much preasure

FTEDiesel

Call your FASS dealer

ct2500

i got a whole bunch of differnt springs at a hardware store and brought mine from 14 to 20 and i can only bring it down to 15 or14.

dsl21

Where on the pump is this spring?

Diesel Doc

inside the return to the tank on the pump

dsl21

I dont know where the return is on my fass.Its just a pump ,no filters,and i only ran 1 new fuel line,guess it uses the factory return line.Am i missing something??

Diesel Doc

oh. I think the spring in that one is internal and not easily adjustable

dsl21

That sucks ,cause I need more presure, i can take it to 5 at wot

Diesel Doc

pm diesel dan. he may be able to tell you what to do

Diesel-Dan

WELL i always start by asking do you know if you gauge is lying to you or not? This is one of the biggest things we see for pressure issues and the HPFP/FASS.

ALSO the HPFP uses a prestrainer. Have you check or changed this? Make sure its a NAPA 3270 Strainer or equiv. If you run a filter, you will see the issue you are seeing. To much restriction and will let pressure drop under load.

BUT if you wish to get a new ball and spring….you can do so.

I would suggest the following if you have an older kit:

WP-Kit –This is the noise update and gives you new o-rings and such to reseal the pump.

PS-1004 – This is our 18 PSI spring for the HPFP

I only recommend these things for pumps that are already out of wnty as the newer ones have a wire seal on them. If the seal is cut, we can not be held responsible for the pump.