I agree with everything written here..

I have my fp gauge plumbed directly, no isolator and no diesel in the cab problems...

cutting the spring will lower pressure if you don't stretch the spring.... for your application, just stretcth the spring. I didn't have to do anything other than install my FASS to get the pressures I'm seeing. I'm not completely sure on what you'll have to do, I'd recommend calling Brad at Diesel Perfomance Products... dieselpp.com...

 

Thanks to all that responded. I will give Brad a call to see what he thinks.

 

I went ahead and stretched the spring a litlle bit and am now getting a little over 12psi; maybe that was the problem all along.

 

stretch it a little further but be careful not to take too much off the spring rate or you'll be back to "low" pressure at WOT...

 

Ok, I will give that a try this afternoon.

 

Hello
I recently bought the FASS for my truck and the above made for interesting reading. Here are my thoughts.

I would call the good folks and tell them about the problem and ask them for either a new spring or a new pump assy. With the $$ invested in this system I expect it to perform without any trouble. Something maybe wrong with your unit and I would call and talk to the folks that built it. Strecthing the spring to try and get the PSIs where I want them don't sound good to me. I am thinking you have either a weak spring or a pump that don't work as good as it should.
Good luck
See Ya
Chris

T

 

The unit I received was set at 10 pounds also. They do make different springs but he recommended just stretching it. The stretch will lose some tension after a while. I also received a heavier spring and will put that in and try it after a while. I have also noticed that the ball will pickup the indentation of the setting which you cannot duplicate. I have wondered if that is where I get some air in the system, from the return and not a real good seal due to repositioning. Looks like the stronger spring would seal better.

 

Only one way to find out I guess.

 

Adjusted the spring again and now have a steady 15psi. We'll see how this does to see if I need a different spring in the future.

Thanks again for all the great advise!