return loop question

[mtgrease]

I am not new to wvo, I ran a 12v for 5 years and many thousands of miles before I found the only ice on a 37 mile stretch of road. I now have a 7.3 crew cab and so far really like it. My only question with the conversion is the purge loop. If the purge loop is open does the engine get the right psi to run correctly? I do not see how the fuel rails can be flushed with diesel and routed back to either the tank or pre-pump and still get the 75 psi needed. I know the pumps flow way more fuel than needed but how can it maintain the 75 psi?

[tubular031]

When my purge valve is open I only see about 25 psi on the fuel rail. I just make sure that when I purge I am coasting or stopped. you do not have to have 50+ psi for the truck to run. Just dont work the injectors when the pressure is low. I put a ball valve on my purge line to limit the flow to keep the pressure up. Without it I would purge and get maybe 5 psi and the injectors were VERY unhappy at idle.

[mtgrease]

Thanks for the reply. That was my concern and if a ball valve partially shut works for you that is what I will try. My conversion might be on hold. My wifes excursion was just diagnosed with bad injector cups and $1500 to have the work done so I may try to do them myself. The parts are only $350.

[tubular031]

That sucks to hear. Good luck with the fix.

Are you setting up the check valve style dead headed system like most run on the PSDs?

[mtgrease]

Yes. I used hydrafroce valves on the dodge but I am going to use check valves on the ford. It just seems like a better fit for that motor. I will be dead-heading the fuels except when I purge and will use one hydrafoce to control the loop. Like you said, I will install a ball valve to control the flow.

[tubular031]

Cool. Let us know if you need any help with your system. Lots of good dudes on here. If you are interested PM me your email address and I can send you the writeup I did for my system when I built it.