Anybody ever built their own aux fuel tank?

[JL penner]

Just wondering if anybody ever attempted this. It sounds like it would be a fun experiment. I have a few ideas of how to design the inside (baffles, fuel pickup... ... ) I'm just not sure how thick I should make the walls. would 3/16 diamond plate aluminum be sufficient? I have all the tools, just need to brush up on my aluminum welding.....

 

[nickleinonen]

1/8" would be more than enough. if i had the space and tools, i'd make my own primary fuel tank that would hold lots of fuel 3/32" stainless or 1/8" aluminum is what i would end up using...

 

[JJW_ND]

1/8" is fine!

We have made several 50 gallon tanks for our work trucks out of 1/8" treadplate steel. We add a baffle front to back to give the tank some strength in the middle of the tank (lots of things smash into these tanks) and another right below the fill to at an angle to keep the slosh from smashing into to fill cap. All tanks have a 1/4 (3/8"??) coupler welded into the driverside bottom of the tank about 1" off the bottom. We screw a street elbow into this on the inside so the pipe intake is facing DOWN and is position about 1/4" -1/2" off the bottom the tank. We want to suck every last drop and all the junk that comes with the fuel. We add a ball valve as close to the outside coupler on the tank as possible. Usually have a street elbow to get the pipe running parrell with the tank and going forward Then hard pipe to get eblow the box of th truck into a electric solinoid valve and "T" into the pickups vent line. No additional pumps or filters. Rocker switch inside the cab activates the solinoid valve and fuel gravity feeds into the main tank. With no pump pushing, you can NOT overfill your main tank. It does fill fast but enough to keep ahead of 5 mpg (test many times).



Three of these tanks have been moved once already to there second truck (we trucks to 100K miles). I have ran 17,000 gallons of fuel through my 96 with over 50% has been transferred as it hold more fuel then the main tank. My tank was built in 1994.



With all these tanks/trucks we have never had a fuel filter, rust, or water issues. And this system works in very cold weather.



jjw

ND

 

[JL penner]

Thanks for the info!!

 

[John - K5AWO]

Extra tanks

I will second the above post. One thing to keep in mind. Since most highways slant down to the right for water shedding, put the drain line on the right side of the tank. I prefer the right front corner because I can point the truck down and to the right to drain all the water from the tank if I ever load up water instead of diesel. Had it happen once back in the '70s.



My tank was 58 gallons, 1/8" steel flatplate, three baffles front edge to back edge, top to bottom. I cut the corners of the baffles back about 1" to allow fuel to equalize between the sections. The baffles do a great job of keeping the slosh to almost nothing.



I installed a Steward Warner fuel guage kit in mine. Don't think I would do that again, the damn thing always seeps no matter how good the gaskets, but it is a nice feature. If the tank is in the bed, that won't matter. Mine was installed in a Suburban behind the 3rd seat. Fumes in the cab are annoying... Had to change out the gasket about once a year.



This tanks was constructed in 1974 for a Suburban. Since then it has seen service in several pickup trucks, and is now in the bed of my 98. 5 CTD as a holding tank for picking up veggie oil or used motor oil.



If I had to make a super long trip across a desert, I can top off with 58 + 34 + 50 (Trax tank). That ought to get me across the metropolitans areas. :-laf :-laf

 

[SEmerson]

I have a 140 gal tank in my bed that I made.

 

[RJOL]

I used diamond plate aluminum. Weld the bottom/sides and baffles first, as you can weld these seams on both sides. After welding the top, pressure test for pin hole leaks. If you find one, use a flat punch and punch the leak spot. This will seal most pin holes. The welding around the drain pipe can be tricky so be extra careful there. The easiest way to the tank is to go through the sidewall of the box and "T" into the vent pipe. Use a ball valve in the line so you can fill the box tank without overflowing the main tank. I know there are a lot of more complicated ways to do this, but this is the simpliest... Have fun...