Engine/Transmission (1994 - 1998) Truck runs better without the overflow valve. ***!!!!

[Highfinance97]

When i first bought my truck it had a PE4200 lift pump on it. the truck ran good for a while and then the lift pump burned up, Got another one under warrenty and burned that one up also.



So i got a Holley blue, burned up that too,Bought a FASS, didnt burn upOo.



Well truck will run for a while then it died, hard starting,then it would start and awhile later it dies.



somehow i realized it was the overflow valves fault,if i run the truck without the ball and spring it will run fine, put it back in and it dies!!

Also I realized that the reason the FASS didnt burn up is because it has its own return. which inturn makes me think the return line is blocked,But why would it make the engine die??



i have been running the truck without the ball and spring for 2 1/2 years now and some people cant believe that the truck even runs.





Michael

 

[DESL PWR]

Very strange indeed. id you ever put a fuel pressure gauge on it? One would think that with no restriction on return fuel flow that the injector pump would not have enough positive fuel pressure on it to feed those plungers.

 

[Highfinance97]

Very strange indeed. id you ever put a fuel pressure gauge on it? One would think that with no restriction on return fuel flow that the injector pump would not have enough positive fuel pressure on it to feed those plungers.

So maybe there is a blockage in the returnline that is keeping the system somewhat pressureized??



What would be happening when i put the overflow valve in and the engine dies



Michael