Fuel pump pickups

[Paul78Zephyr]

Hi all,
Im trying to understand this type of fuel tank pickup made for late model EFI Mustang fuel tanks:

It says that these are made to eliminate the in-tank pump for use with an external pump. But this means the external pump has to PULL the fuel UP from the tank and I thought the pumps were not made for this - that the pumps should always be gravity fed. Anyone have insight into how the pumps work with this setup?

Thanks,
Paul

 

[superhuaman]

no, the pumps do not need to be gravity fed. i dont know where you got that idea-maybe from seeing like a drag car with the hoses going to the bottom of the tank. that setup is called a sump and has nothing to do with gravity. its so that the fuel goes toward the pickup under straight-line acceleration, and is the preferred setup for out-of-tank pumps. but the thingie you have pictured should work just fine. just make sure there is a filter between the pump and the pickup, since it doesnt look like a stock sock should fit that tube. or maybe it would...try it...

 

[Blk91stang]

I would NOT do what superhuman just recommended. I would do a bit more research before doing this. There is a reason why NO ONE else is running a non-gravity fed external fuel pump. Pretty sure that fuel needs to ALWAYS be in the pump during startup. With this setup, each time you crank it, the pump is bone dry.

Superhuman can you tell me where you have EVER seen an external pump being used when it wasn't being gravity fed by fuel or at the very least picking up the fuel below the top of the tank like this setup?????

Get back to me, I'd love to see it being done.

 

[superhuaman]

i guess youre right matt...if someone used the pickup pictured, theyd probably have the pump down where the stock filter is, so it would be kind of below the fuel level in the tank

 

[gtxracing]

Superhuaman sorta wrong on that gravity feed portion. Some do some not. If you have a carb setup and you have a 4-8psi pump, you must mount the pump below the tank which is true because before I bought the RCI tank to mount in the trunk, I uanked my baffled stock POS tank out from beneath the car and I had rigged the pump to pump out the gas into my RCI tank. It wouldn't even squirt the gas into the new one but soon as I dropped in to the ground it started pumping.

But if you have like 20psi+ pump then yes, gravity feed procedure is not needed. No the question is what difference does it make because I have a Holley Red pump and it's made for carbs. I had mine clear to the top and no pumping problems.

 

[Paul78Zephyr]

Guys,
Thanks for the replies.

Im as confused as you are as I always thought that any fuel pump - low or high pressure - needs a supply of fuel on its inlet side, either by being submerged in it or gravity fed. This pickup seems to work by assuming the pump can 'suck' the fuel up from the tank. It does not seem to make sense, yet I assume the manufacturer knows it will (the picture is of a Mallory part from the Summit Racing catalog). Here is very similar one from Paxton:

View attachment 403197

Paul

 

[Busted07]

While you guys are on this topic, i have a few questions. I bought that same pickup above (mallory i believe) and am about to run my fuel system, but had some similar questions.

-do you have to run a retun line on a carb'd setup?

- if not, can you just cap that other line off?

- i didnt see a sock listed for the bottom of that pickup, should i just take it to the parts store and try to match one up?

- did you run your fuel line up the passenger side? if so, how did you run it into the engine bay? (up the firewall, or...? )

not meaning to jack the thread, but since you were on the topic already it saves me from starting a new thread

 

[superhuaman]

no fuel return line for a carb setup - IF you have a low pressure pump and/or regulator that does not require a return...ie a deadhead regulator and a pump designed to work with one.

 

[Busted07]

no fuel return line for a carb setup - IF you have a low pressure pump and/or regulator that does not require a return...ie a deadhead regulator and a pump designed to work with one.

It didnt say anything in the paperwork that came with it, so im guessing i do not require a return.. this is the one i got if that helps

View attachment 403191

 

[superhuaman]

It didnt say anything in the paperwork that came with it, so im guessing i do not require a return.. this is the one i got if that helps

View attachment 403189

it looks like it needs a return...see how the regulator has three ports?

 

[Busted07]

it looks like it needs a return...see how the regulator has three ports?

well ****! lol... thanks for the info man. I guess ill have to buy some more braided line... grrrrr

 

[superhuaman]

no prob, im here to help (usually)

 

[Busted07]

no prob, im here to help (usually)

Actually, I just called summit to see if they had a return line kit, and the guy asked what regulator and stuff i had... i told him it was the pump kit, and he said that the regulator that comes with it has 1-in and 2-outs on it to use with a dual carb setup. He said i dont need to run a return line as that is a deadhead setup. All i have to do it plug it with a 3-8 pipe plug...


Whew... looks like i can run the fuel system this weekend.

 

[superhuaman]

 

[jrichker]

It's been a long time since I looked at a carb with a mechanical pump, but most of them will pull fuel uphill. The diaphragm type pumps will pull some vacuum and can pump fuel even though they are above the fuel level in the tank. Some of the cheap electric fuel pumps are nothing more than a solenoid motor and a diaphragm.

If you use a pump with a suction line, the shorter that line is, the better off you are. The vacuum in the line can make the fuel boil and vapor lock at a much lower temperature than it would at normal atmospheric pressure.

 

[Busted07]

Hey, i learned something either way, no worries!

 

[smr]

Actually, I just called summit to see if they had a return line kit, and the guy asked what regulator and stuff i had... i told him it was the pump kit, and he said that the regulator that comes with it has 1-in and 2-outs on it to use with a dual carb setup. He said i dont need to run a return line as that is a deadhead setup. All i have to do it plug it with a 3-8 pipe plug...


Whew... looks like i can run the fuel system this weekend.

yeah the two output ports on your regulator can also be setup so you can run a individual feed to each side of the carb if you dont want to run fuel log(assuming its a double pumper) if not then you just plug one.

 

[Busted07]

yeah the two output ports on your regulator can also be setup so you can run a individual feed to each side of the carb if you dont want to run fuel log(assuming its a double pumper) if not then you just plug one.

Well i have a 2 5/8 fuel pressure gauge.... can that come off of one of the "out" ports?

 

[smr]

sure

dont see any reason it couldnt..the regulator regualtes the incoming fuel fromt he bottom feed. This is standard dead head (non bipass) style regulator. Both side of the outgoing ports will have same pressure.

 

[Busted07]

dont see any reason it couldnt..the regulator regualtes the incoming fuel fromt he bottom feed. This is standard dead head (non bipass) style regulator. Both side of the outgoing ports will have same pressure.

If thats not common, where does everyone else run thier FRP from ?