Rear mounted gas tank stumper

[Jimal]

The punch list is shrinking on my '65 K10, but I have one last piece that is proving to be a pain, the rear mounted gas tank.



The truck came with this tank installed by the PO, but it was set up for a newer bed. When I installed the correct bed and components, the side filler lines up right under one of the bed crossmembers (note the notch in the frame).



My idea was to have the tank modified to use the '61 Impala filler neck that is sitting on top of the tank in the first picture. The concern I'm having is getting enough of an angle on the filler to that gas goes in but doesn't slosh out, while maximizing the usable capacity of the tank. This is going to be a work truck for me, so I'd rather not deal with a bed floor mounted filler.

I'm stumped. Any ideas?

[dodgiesdad]

I am guessing from your description this is a short bed fleet side. I just went through this with my 65 K-10 short bed fleet side, your pictures look oh so familiar to me. I solved this dilemma by moving the rear crossmember of the frame back approximately 2", this enabled me to move the gas tank back by the same amount. I had played with a drop mount for the tank that would have cleared the crossmember you shown in your picture, I was unhappy with this as in my opinion it held the tank to low. I then made a extra crossmember out of angle to mount infront of the gas tank and actually cut out the center of the crossmember. I was not happy with the flimsiness of the outsides of the original crossmember the wheel tubs set on them. So I put in a 1" body lift then I notched and reinforced the crossmember shown in your picture. This also gave me clearance for the air cleaner I wanted to run. As part of notching the crossmember I also had to clearance the side of the flanged mount to allow clearance for the pipe. I also had to in large the filler neck on the gastank 1 1/2" to match everything else. Finally I bought a flat fuel filler door kit from Summit made by "Tanks". I installed this in the bedside and had a pc of exhaust pipe bent it fit the supply pipe that came with the kit (2"ID to 1 1/2" OD) and a short pc of 1 1/2" fuel hose to connect them. I also made a vent 1/2" pipe which I welded into the filler neck as well. It sounded like such a easy project but the amount of work was staggering. Sorry I dont have any better pictures in the computer to share right now.

[Jimal]

My truck is a short step, but I see where you're going. I'm thinking about a tow bar back there to help protect the tank. The part I forgot to memtion is that I want to mount the filler straight out the back, behind the license plate.

[PGSigns]

On these trucks the plate is to low from what I can see. I went through this when I put the tank in my 66. I looked at some early model cars with the filler in the back and on the side and all seemed to have about 6" or more of drop to get the fuel to run down hill and stay there. With the bottom of the bed being below the top of the frame I could find no way to pull it off in a manner that would not fill the pipe with fuel when moving. The need for a vented cap just meant a leak. So in the bed it went.
Jimmy

[Jimal]

After looking at the other style rear mount tank, I had an idea. Short term, I could start with a top fill tank then route the filler hose over to inside the passenger side fender.

Longer term, I'm tinkering with the idea of running the filler hose further ahead, along the outside of the bed side and up to the step, where it would plumb into one of these, mounted on the step.



Either to add capacity or just to act as a cool cover to the filler while offsetting the spare on the other side.

[Jimal]

OR

The idea I had tonight. My fenders have provisions for what I assume are the back up lights.



Using the '73 vintage side mount filler I purchased previously, along with some appropriate size fuel safe hose (and possibly some aluminum or steel tubing) I will route the filler and vent from the opening in the top fill tank under the bed and over to the driver's side back up light opening. And if I really want to be slick about it I'll modify the light that was going to go in there to serve as the gas cap, keeping in mind that this means I'll only have one working back up light.