Has anyone relocated there gas tank in a 67-72 F100 from inside to under the bed? If so what parts did you use and what did it take?

 

[updated:LAST EDITED ON 06-Feb-02 AT 11:32 PM (EST)]I wanted two fuel tanks on my 1970 F100 because I pull a car trailer a lot.

So I went looking, and found a gas tank off a 1978 Mustang II. It has a hump in it to make room for the spare tire location in the trunk of the car. It fit between my frame rails (and my dual exhaust) just gret.

I had the tank cleaned and the filler neck moved so that I could put the filler/cap on the side of my bed behind the fender on the driver's side (the tank is turned 90 degrees from its original positioning). The filler hose is routed between the frame and the bottom of the bed. It is crimped a bit, but no worse than the factory install on my wife's 1981 F100.

This is how I installed it:

1) I welded a 5/16" x 2" strap across the top of the frame rails for the "new" tank to rest up against.
2) I went to the hardware store and bought two mobile home tie-down straps to use for mounting the tank (they have a swivel (hinge) on one end).
3) I fabricated two t-bolts out of all-thread for the other end of the straps. I used t-bolts for greater strength when welding to the frame (the top of the 't' is welded to the cross-member or strap).
4) With the tank held in its new place with a jack, I marked the locations for the t-bolts and the swivel (hinge) ends of the straps.
5) With the tank removed, I welded the swivel (hinge) end of the straps to the cross-member and the 5/16"x2" strap (on the driver's side).
6) I then welded the t-bolts to the original cross-member and the 5/16"x2" strap in the locations previously marked.
7) I now had the mounting for the tank in place with the exception of how to connect the opposite end of the mobile home straps to the t-bolts. So, I folded the straps over (doubled them) at the point where they would tighten up against the tank and cut off the excess.
8) Then I took some soft round iron stock (available at the same hardware store) and cut two lengths from it as long as the strap is wide.
9) I drilled a hole in the middle of each of the two lengths of stock large enough to slide up on the t-bolts.
10) I placed the two pieces of stock in the loops on the ends of the straps and welded the strap end (the doubled over part to the long section of the strap.
11) I jacked the tank up into place (using strips of an old inner tube to insulate the tank from the cross-member, the 5/16"x2" strap, and the mobile home straps), pulled the straps up and onto the t-bolts and installed two self-locking nuts. The straps pulled up nice and tight against the tank without crushing it.
12) I measured the location for the upper end of the filler tube on the outside of the bed and cut the hole (made the mistake of putting it too low the first time and had to fill in the side of the bed). It's now above the molded area (where the 'chrome' strip would mount.
13) I installed the upper section of the filler tube (with gas cap) and used fuel hose to connect to the filler tube on the tank (over the frame).
14) I mounted an after-market fuel solenoid on the inside of the frame rail near the point where the in-cab tank line passes through the frame.
15) I ran new steel fuel line from the solenoid to the Mustang II tank, and used "rubber" fuel line for the last six or eight inches).
16) Since I have a instrument panel out of a '67 with idiot lights, I had already installed after-market gauges in an overhead console I had made. So, I added another '67 fuel gauge to the instrument panel (now have two gas gauges).
17) Rewired the original fuel select switch (this is a donor cab) in the dash (originally, it only switched the gauge between two tank sending units) so that it controlled the fuel solenoid.
18) Using the Mustang II sending unit (same resistance range as the F100), I wired it to the "new" fuel gauge. I know at a glance how much fuel I have in both tanks.
19) Went to the station and filled up both tanks (wallet collapsesd).
I now have 32 gallons to burn.

I know it seems like a lot of work when you look at all the steps (and I may have missed one or two), but I did it all in less than one day. It works just great; I've not had any problems with the installation.

Also, I used the original wiring in the dash, cutting and moving it where necessary (to minimize butchering of the harness).

OldFords Bad attitudes

 

On those old Mustang II's where did there fill line come out? Were they the cars that had the flip-down license plate with the fill line and behind it? That is the plan I have for my 67 and 68, if it was meant for that it would be the perfect fit.

-j.banks-

 

The filler tube on the Mustang II is on the driver's side rear quarter panel (fender).

The reason I had the filler tube moved for my truck was to align the gas tank hump (turned to allow for the spare tire in the Mustang II) to the front so it would fit further up between the frame rails (giving it more protection due to th ehigher ground clearance).

My son just removed the tank from under the cab of his '55 and put one between the frame rails in place of the spare tire (which is in the bed). He had the filler tube moved on the tank so he could do just what you want to do. He used the flip-down license plate holder from a donor-car and everything works just fine.

You should have no problem locating the filler behind the license plate. Just be sure that you protect it well if you are in the habit of backing up to hook a trailer often. That's why I didn't locate my filler there (I pull a car trailer and a trash trailer on a regular basis, and sometimes experience "rough" line-ups between the hitch and the trailer ball).

OldFords Bad attitudes