Which adjustable regulator also acts like a check valve? I have to prime the key 3-5x to get the truck to start without extended cranking. I've tried different pumps, I do not think its the pump. It might have something to do with the Walbro 450 having to fill large -8 lines but I also think it might be the regulator.

 

Regulators wont hold pressure in lines.....my big ***** looking aeromotive regulator bleeds off just as my magnafuel did

If you take one apart youll see rhere is nothing to keep pressure there youre only restricting the flow.

Even big single pumps bleed off pressure

 

Im in the same boat aswell with this. I run an aeromotive 340 intank and have the aeromotive boost referenced regulator and i most of time have to prime mine a couple times aswell and truck fires right up. Otherwise a single prime and flip of the key turns over numerous times before firing. Ive wondered about a check valve aswell for this setup!

 

the fuel pressure probably bleeds back through the pump and not the regulator, a one way check valve in the supply line could solve it but would probably be a restriction

 

My fuel lab even states in the info it comes with that its not designed to hold pressure when pump is off.

On that note though you shouldn't have to prime it that much. What pump do you have? Sounds like it's draining back.

 

Magnafuel told me to put low cracking pressure check valves between the fuel rails and the regulator. So if you have checks that take 1/2 psi to open, they will maintain 1/2 psi when the pump is off.
Having no air in the system and slight pressure will give instant full pressure and starts the same as stock, instead of having to refill and then pressurize a system that has drained because of the aftermarket regulator.

 

If I prime mine it goes up to set pressure (55psi) within 1 second and will hold 20-30psi for an hour or so. Walbro 400s and aeromotive regulator.

 

I doubled my key on prime time from 2 seconds to 4 seconds and it took care of mine. I'm not sure if all ECUs have that option.

 

I can't find it in HP Tuners with my 2002 OS. Am I looking in the wrong place?

 

It's in there, mine is an 02. I have mine set for .25 seconds I think