Fuel pressure regulator question

[Tio Pancho]

Looking to buy a fuel pressure regulator. If an adjustable regulator has a port for fuel return to the tank, can it be used with the return port plugged as a "dead head" regulator? It does not seem right to me that it would work.

School me please.

Thanks
Frank

 

[Skinny Tire AH]

Looking to buy a fuel pressure regulator. If an adjustable regulator has a port for fuel return to the tank, can it be used with the return port plugged as a "dead head" regulator? It does not seem right to me that it would work.

School me please.

Thanks
Frank

I don’t believe you could. It regulates pressure by dumping excess into tank.

I just changed my Mercury internally reliving valves with Weldon adjustable, return to tanks ones. If you plug that port, where does excessive pressure go?

You’d be shocked at how much fuel returns to tank.

 

[Tio Pancho]

Nganga that's what I thought. But as I have no experience I thought I would ask. Looks like I am still shopping. Thank you.

 

[Racey]

N

Looking to buy a fuel pressure regulator. If an adjustable regulator has a port for fuel return to the tank, can it be used with the return port plugged as a "dead head" regulator? It does not seem right to me that it would work.

School me please.

Thanks
Frank

No, a bypass regulator has to bypass, mainly because the fuel pump behind it would be able to massively exceed the pressure. A carburetor with a low pressure regulator and a diaphragm pump, will not be able to overpower the regulator because of inherent design.

 

[Blackmagic94]

Dead head is bad anyways.

 

[Teague_JR]

What’s the config? EFI? Single or dual tanks?

You can work around returning to the tank by returning to the INLET side of the fuel filter head through a fuel cooler. Return to tank is still best.

 

[Tio Pancho]

Its an 83 Crusader jet bote with an old school mostly stock 454. Pump is a mechanical 110 GPH bought for future upgrades. Looks like it might be overpowering the carb. Want to bring the pressure down but not at the expense of a major project with the tanks. Would rather buy a stock pump which would most likely bring the flow down.

 

[Teague_JR]

A deadhead carburetor regulator will do the trick. If you have one it might be malfunctioning … the aero motive ones work good. Old style chrome Holley ones have had some QC issues last 5 years

 

[rivermobster]

Its an 83 Crusader jet bote with an old school mostly stock 454. Pump is a mechanical 110 GPH bought for future upgrades. Looks like it might be overpowering the carb. Want to bring the pressure down but not at the expense of a major project with the tanks. Would rather buy a stock pump which would most likely bring the flow down.

Have you put a gauge on/in the fuel system yet?

That would be the correct place to start so you know what you're up against.

No point in spending money on a regulator, if you really don't need one.

Find out what your existing pressure is First.

 

[Skinny Tire AH]

Just for reference, this is the fuel system “theory” I fought with on my boat. I had lost 6-7 Aeromotive fuel pumps on the factory set-up.

If you follow the fuel flow, you can see it essentially dead-heads at the regulator, after it runs through the fuel rails. The bypass pressure runs back through the system, entering in the water separator.

I replaced the entire fuel system with Weldon pumps, Weldon regulator, removed the cooler from the loop (Teague advise).

Also added return to tank 1/2” hose.

Seems to work perfectly now.

 

[was thatguy]

On my little hot Rod boats I’ve run both.
The Miller has a 625 HP BBC.
The most basic fuel system is on that boat.
Blue pump to the matching Holley regulator. No bypass, from the regulator to a fuel block (with psi gauge before the block) from 4 way block to each bowl on the dual 750 Holley 4150 carbs.
6 pounds on the regulator. Full deadhead system.
This has worked perfectly for 15 years with zero failure. It’s a minimal system based on requirements. The pump and matching deadhead regulator are almost 15 years old with zero issues.

On the hydro I had an aeromotive A2000 bad boy with the accompanying 4 way billet bypass regulator.
That was a more advanced system for a higher HP requirement.
Relay operated pump to the regulator with the tank return and 4 way feed to the dominators.
So your question is somewhat ambiguous without knowing the demand.

As Steves illustration above shows, an injector system requires an end of run dump to tank, generally speaking. Any high demand system is likely to require a pump that will not enjoy being deadheaded. Hence the failures.

So you can’t just slap any old regulator of any old kind into any old pump or system.
I’ve always had the best results using whatever regulator the pump manufacturer recommends with that pump and the system it’s designed for.