2nd Gen Non-Engine/Transmission what draw straw do I need for fass II pump

[VHolloway]

99 2500 4x4 fass II pump that is louder than the truck



I need to do something

but when I change the fuel filter it stops that loud noise for a day or so

or let some fuel out of fuel filter canister

is this air

 

[VHolloway]

ok thanks

shame on the mess

 

[Jim Fulmer]

Isolators on the pump mounts will help, but a pump will tend to be louder when it's having to pull fluid, they don't pull well! I'd go with a 5/8th's" or 3/4"!



Jim

 

[LowFly]

99 2500 4x4 fass II pump that is louder than the truck



I need to do something

but when I change the fuel filter it stops that loud noise for a day or so

or let some fuel out of fuel filter canister

is this air

What you could also be hearing is the relief spring resonating. As we try to catch every one that makes some noise on the bench before we ship them, they some times act differently in the truck. I have found that the springs will relax and stop making noise after a while. The springs have a shrill high pitched tone of sorts. The motor is more of a low pitch hydraulic sound. You can try to draw out of a bucket of fuel first. If the pump noise changes, you might be on to something and a draw straw or STK-1001 might help. If noise stays the same, you might be spending your money on something you might not need. HPFP’s are not affected by restriction as much as the FASS. They usually only show issues under WOT by big pressure drops. This is because the HPFP internally bypasses and only moves the fuel that the engine needs.