[cummins24valve02]

I just installed a new dtt assassin fuel pump and after the first start my fuel pressure was about 12psi, I was ecstatic. Ran it to the store to put some fuel in and noticed my fuel PSI getting up to 38... I rechecked everything and its all hooked up right. The only thing we had to modify was re ran the return line back through the original feed line because we didn't receive enough fuel line to make it back to the tank. Is there any kind of check valve or something that wouldn't let the fuel return? I know I can't run it this high but now I'm stuck... Any thoughts or suggestions? I did make sure we put the gears on the correct was, big one on the pump, little one on the harmonic balancer.

 

[irish power mad]

Ya that lp psi is a tad to high. I thought there was a regulator on the assassin to regulate the pressure???. I don't see the stock return being a problem, otherwise all the high output electronic lp's would have a similar issue.

 

[j-fox]

If you run the return to the feed line , it will see the return pressure and think it is low. When it is higher. It is a reference and if it is 20 the pump will add 15 or so.
must run the return to the tank.

 

[Jbh97009]

I think this was covered in ghostman's old thread that was just dug up. Look in performance parts and look for a thread called 'a lift pump to end all lift pumps' or something along those lines. On the last page or so he talks about this very issue and how he fixed it.