Removing front fuel tank -- F150

jkrell
Posts: 232
Joined: Sat Apr 27, 2013 10:09 am
Bronco Info: Ford F150 Flareside
Location: So Cal

Removing front fuel tank -- F150

Post by jkrell »

Anybody have a how to on fuel plumbing modifications needed when removing the front fuel tank from an F150? I'm planning to remove my front tank to make room for shock mounts, and and mount a larger rear tank. Currently, if I just run on the rear fuel tank it seems like over time it fills the front tank up so i'm assuming there is a return line back to the front tank I will need to modify. Anybody on here done this?

Thanks!
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johncharlesb
Posts: 510
Joined: Fri Mar 12, 2010 7:59 pm
Bronco Info: 1962 f100, 1995 Bronco

Re: Removing front fuel tank -- F150

Post by johncharlesb »

With the later model trucks the fuel pump prevents fuel from entering the unused tank. If the tank is filling up, it is a sign of a bad fuel pump in that tank.

The earlier fuel injected trucks used a frame mounted selector valve that switched the tanks and low pressure pumps in the tanks with a single high pressure pump on the rail past the valve.

I am not sure how the Cali trucks are done, as they have different regs, but there should be a fuel supply to the engine, a vent line between the tank and the charcoal cannister, and a return line between the pressure regulator and the tank.
big-d
Posts: 54
Joined: Tue Jul 12, 2011 12:29 pm
Bronco Info: 1987 F150, 351W/418 Stroker, E4OD, F250 1356 W/fixed yokes, Sterling 10.25, D50 TTB 4" over

Re: Removing front fuel tank -- F150

Post by big-d »

I am going to guess that your truck is a 90 or earlier? I had the same thing happen to my 87. There is a black divertor valve that handles the fuel flow for both tanks. (You can get a patch kit for the fuel injection lines that can be used to make short sections or splice in with). I would remove the divertor valve and the lines for the front tank. Then either run all new lines from the rear tank or make a couple short lines with the male efi fittings on both ends and hook back up the remaining lines. There are only 1 supply line and 1 return line going from the divertor valve to the engine. I hope that makes sense.
jkrell
Posts: 232
Joined: Sat Apr 27, 2013 10:09 am
Bronco Info: Ford F150 Flareside
Location: So Cal

Re: Removing front fuel tank -- F150

Post by jkrell »

Sorry should have been more specific. Its a later model f150, 1993.

Interesting to hear that there is a bad fuel pump in the front tank thats why fuel is flowing that direction.

Is there a diverter valve that I would need to replace in the later models with a single tank model? I would rather not patch/splice lines but would prefer to completely eliminate the plumbing for the other tank. Patched lines seems like one more thing to possibly go wrong in the middle of baja.
Jbfab
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Joined: Mon Nov 22, 2010 12:30 pm
Bronco Info: 94 centurion bronco 5.8/zf many mods more all the time.

Re: Removing front fuel tank -- F150

Post by Jbfab »

Here is what i did when i removed my front tank. I dropped the tank and disconnected the pump. Once its drained i cut the quick disconnects off of the top of the pump. Crimped the line shut about an 1" from the end and welded what was left open to insure it was sealed. Its SS and i used my mig and then dipped the ends in some por15 to keep it from rusting. Zipped tied the lines and harness up out of the way and never looked back.
big-d
Posts: 54
Joined: Tue Jul 12, 2011 12:29 pm
Bronco Info: 1987 F150, 351W/418 Stroker, E4OD, F250 1356 W/fixed yokes, Sterling 10.25, D50 TTB 4" over

Re: Removing front fuel tank -- F150

Post by big-d »

That or just replace the lines with something better. Yours are already over 20 years old...
blueoval8493
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Joined: Fri Apr 27, 2012 8:52 pm
Bronco Info: 1994 F-150 super cab with 347.

Re: Removing front fuel tank -- F150

Post by blueoval8493 »

They're 20 years old but all stainless correct? I live in the rust belt and have always had a 90's smthing full size ford around and have yet to see them rot. I had a 96 that would fill the front tank when using the rear. The valve they're talking about is in the pump itself on the 93-96 i believe. I don't have thelink with me but i believe it's high flow fuel injection or smthing that sells the factory fuel pickup with a walbro pump installed in it. Pretty slick drop in install and if i remember correctly pretty affordable. U can get up to a 250 gph pump i think too if you have or are planning engine mods. If you decide to remove you need to block off both feed and return lines and keep in mind that a leak could be very dangerous.
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