Electric Fuel Tank Selector Switch and Electric Fuel Pump--Pics Please

[GatorDone]

I'm upgrading the plumbing of my fuel system including 3/8" hardline, Carter P4070 electric fuel pump and electric fuel tank selector switch. As I looked over threads upon threads of info, I'm not sure I'm understanding the setup completely. Here's what I got from my readings:

Basic map of plumbing (as I understand it): Main tank and aux tank --> fuel filter --> electric fuel switch --> electric fuel pump --> fuel filter --> carb

Is this somewhat correct? Am I even going to be able to use 3/8" hard line? My plan was to mount the selector switch and pump on the driver-side frame rail between the main and aux tanks.

Pictures of fuel plumbing including the electric switch, filter(s) and electric pump would be much appreciated.

 

[blubuckaroo]

I've gone back to a mechanical pump but this is how I plumbed my electric pump/selector valve:
Both the valve and pump are mounted to the drivers side frame rail between the auxiliary and main tank. This provides the shortest suction line possible for both tanks. The hoses from both tanks are connected directly to the valve, the valve connected to the suction of the pump, and the pump discharge line runs to the filter at the carburetor. I don't like to put any filters in the suction side of a fuel pump. Fuel pumps have pretty low suction and have enough trouble pulling in fuel already.

 

[Phil76]

Here's a great site on wiring in your fuel pump, so you don't burn it up: http://www.how-to-build-hotrods.com/electric-fuel-pump.html

 

[JefeAZ]

Main tank-->fuel filter v
................................--> electric fuel switch-->electric fuel pump-->fuel filter-->carb
aux tank-->fuel filter ^

Only thing I did differently was filters between the tanks and the new switch. Editted your "map"

Am I even going to be able to use 3/8" hard line?

From the switch to the motor, yes. Kind of tough between the filters and the tanks. I used rubber fuel line

My plan was to mount the selector switch and pump on the driver-side frame rail between the main and aux tanks.

Thats what I did. Might need to fab a bracket like mine

Stock tanks? All hooked up already? Evap/Vent lines run?

This may also help(read through the last post): http://classicbroncos.com/forums/showthread.php?t=201013&highlight=kink

This too: http://classicbroncos.com/forums/showthread.php?t=203524&highlight=tank

 

[Steve83]

On Frank's truck, we used a filtered low-pressure pump outside each tank. Those go to a 6-port selector valve, then a reservoir, then the hi-pressure pump, then the filter, then the fuel rail. The return line goes to the reservoir, selector, & tanks. His wiring is very similar to the Left & Right panes in this diagram (not the center ones):

 

[Broncobowsher]

Main tank-->fuel filter v
................................--> electric fuel switch-->electric fuel pump-->fuel filter-->carb
Aux tank-->fuel filter ^

That is how I did it as well.

Seperate filter for each tank, if one goes bad you know which tank has the junk in it. I used large clear filters. I actually found out that the main tank had junk in it once. Another time after several years of the new tank I started having issues on the highway. The filter for the main tank was clogging up so switched to the aux and made it home. With 2 filters, changing the selector valve from one tank to the other also switches filters.
The pump to carb filter is just a backup. Anything that may come from the selector valve or pump can be caught there. You should never see any dirt in that filter. If anything that is where I would put the fine filter at.

The P4070 has a mesh filter in the pump. Not really servicable. That is why I like to keep a disposable filter before the pump. Nice and large so it does not restrict the flow.

 

[4x4man514]

Ok so I'm gonna dig up an old thread. Cause I am stuck.

Am I reading this right that y'all have a low pressure pump and filter before the selector? Then a accumulator then the high pressure then another filter?

That's three pumps, three filters and a selector switch?

Where in the world do you put all that equipment?and how do you keep it neat looking? That's a whole lot of lines. Esp for efi with return lines.I would love to see some pics. I can't figure out where to plumb all this in.thanks!

 

[garberz]

You're right, it's too much. When I did my EFI, I put the pump in the 23 gal. tank, I run an EFI filter on the drivers side fender well, and my supply and return lines run down the drivers side frame. I'm just running the single tank. I think a lot of EFI people that keep the aux. tank, just manually transfer fuel to the main with a LP fuel pump.

Mark

 

[4x4man514]

We'll I bought the wrong 23 gal tank quite a while ago so I have no access inside the tank. And I do want to run both tanks. So here I am. Before my eb burned I had the 6 port switch in there and functional with a carb and mech pump so I think one low pres may be enough to pull from either tank but even then I need one lp pump, one hp pump,the switch, and accumulator(maybe that would be sufficient as a filter).

But that's still a lot of hardware to install somewhere. Surely somebody has done it. Has anyone got any pics? I'm doing this full frame off so I really don't want it to look like a jumbled up bird nest under there.

Thanks for all the input guys!

 

[broncnaz]

Filters go inline at the tank line from selector valve to pump then line out of pump to engine. Another filter at engine.
Really its not all that much except a extra filter or two.
I only run two filters one in the line from the selector switch to the pump and the other at the carb. I figure with the clear plastic filters i will see them getting dirty when doing regular maintenance and can change out at that time so a filter at each tank is uneeded for me. But I will always try and run a filter on the inlet side of a electric pump. You'd be suprised at how much stuff is in your tanks no matter how clean they were.

 

[dclack]

I think there is a lot of confusion here between carbed and EFI setups. If I read it correctly, the original thread is about a carbed engine and 4x4man514 is talking about fuel injection. This is why it's best to start your own thread instead of digging up an old one.

With my EFI, I'm running stock tanks with a high pressure pump in each, supply to the switchover valve, to a single EFI filter mounted on the rear frame crossmember, and steel lines to the engine. The return comes straight back to the switchover and to the respective tank. If you are going to run 2 external pumps, you put a filter and the low pressure after the switchover valve, to the acumulator, then the high pressure after the acumulator, usually under the hood. Others have also just used a single high pressure pump back as close to the tanks as possible (after the switchover valve).

Personally, I would modify the 23 gal tank and use 2 internal pumps. After a day of wheeling and 1.5 hrs from home, my rear pump decided to take a crap on me; wouldn't put out more than 10 psi. I flipped a switch and drove home on the side tank.

 

[4x4man514]

Thanks for the input guys! And yor right I should have started a new thread. I like to try and research before I start something over that has already been hashed out and I guess I just got lazy.

 

[broncnaz]

No big deal but if you have EFi and plan on running a external hi pressure pump then you really only need 1 low pressure pump to pull fuel out of the tanks. There is no real differance between EFI or carbed in this situation. The low pressure pump either feeds a carb or a hi pressure pump.

 

[4x4man514]

Thanks. I think that is the route I'm gonna go. I spoke with someone who put their high pressure pump and acc up front in the bay. I kinda like that idea. Not as much high press line. And not as much cluster down below.

 

[Steve83]

Am I reading this right that y'all have a low pressure pump and filter before the selector? Then a accumulator then the high pressure then another filter?

That's three pumps, three filters and a selector switch?

Yeah, that's how Ford built the early EFI trucks, so I tried to copy it. I couldn't figure how to make Ford's 2nd fuel system work in an EB tank on the budget I had.

Where in the world do you put all that equipment?

Underneath, inboard of the driver' frame rail.

and how do you keep it neat looking?

By covering it with the body. ;D

That's a whole lot of lines. Esp for efi with return lines.I would love to see some pics. I can't figure out where to plumb all this in.thanks!

Did you follow the links that have already been posted in this thread? Start with this one & keep going to the NEXT until you see the intake manifold: