also I found a real nasty metal fuel tank from an '88 ford bronco 2 35gal, but it was rusty as hell on the inside, I thought gas tanks were galvanized from factory ?? Also I am no metalurgic expert but can you weld galvanized to regular steel as long as you "knock off" the out galvanized coating ?? How are our gas tanks welded from factory ?? mine ('79 volare original tank to my knowledge) appears to be spot welded around the perimeter, what kind of sealer was used to keep it leak free ?? I see POR-15 has a tank sealer, anyone ever try it out ?? I wonder if it bonds to both galvanized and regular mild steel ?? What about welding galvanized on galvanized ?? I know the dangers associated with welding galvanized, and would be welding outdoors with a fan blowing and respirator, i plan on widening, and increasing the depth, and sumping/baffling my tank, and finishing around 35-40 gal capacity, I like to go on long road trips and stopping to fill up, or carrying extra gas in gas cans is annoying and takes up much needed room in the trunk for camping gear lol. I also was thinking that I might be able to get away with riveting a spacer in between the top and bottom halves of the tank, I have aircraft grade fuel tank sealer that i would use like glue to bond the top, spacer/middle section and bottom, or is there a better sealing compound out there ??

I know a ton of questions, but i appreciate all the help i can get

-Mike

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I am the Guardian, I hate helos, everything leaks.......

Just some thoughts:

For as much customization as you list - widening, extending, baffles - I wouldn't start with an old tank. You'll be fighting different metallurgies, thicknesses, and conditions of metal; dealing with shaping and fitting work; and doing several more feet of welding. More chances of a leak right off the bat AND in the future.

If I needed a custom tank, I believe I'd contact a custom builder.


Remember that the added volume has to go somewhere, so it would be necessary to mock up a tank carefully to make sure it will clear everything and still be accessible/removable for service.

Making the tank deeper may make it more vulnerable to damage.

Sealers: Gasoline ain't what it used to be. Literally. The alcohol and other additive contents change with time, supplier, and geographic area, so what was a good sealant years ago over here may not be this year over there.

Coatings in old tanks have had to deal with various grades of gasoline, additives, water in all forms, dents, and other stressful situations over the years. Coatings wear, even in a "just" a fuel tank environment.

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"When you find a big kettle of crazy, it's best not to stir it." - Pointy-haired Boss

1964 Valiant V200, 225/Pushbutton 904
BBD, CAI, HEI, LBP, AC, AM/FM/USB, EIEIO

The weight also, if your leaf springs aren't upgraded an extra 200 lbs of fuel may not be welcome by the rear suspension (I know that I can put a disassembled slant six in the trunk of a duster and the 6 leaf spring packs are fine with it...I know that the 5 leaf setup barely tolerated that kind of abuse heading to the machine shop)....

I know that a good sheetmetal shop can make one without a problem and if you have a fuel sending bung from the old tank they can work with it or try and replicate it...I've made tanks out of black iron for clients that were going to have them coated...stainless tig'ed tanks are best, but the time and material becomes cost prohibitive over buying a stock replacement...

FYI.

-D.Idiot

I can build a custom tank from scratch, just out of steel, I have a mig welder, no tig yet, I just wanted to widen and add depth to a stock tank, I can buy a new tank and go from there, but this is a what am i capable of making, money isn't the issue, its the fun of making it, built not bought my man. I would drill a crap ton of hole and stitch weld it all together. I was looking at getting a 35 gallon '88 bronco 2 tank but it was trashed with rust, may still go back for the fun of it and grab it, BUUUUTTTT it had a massive steel skid plate covering it, and that is what i would do to protect mine, there is literally nothing in the way of dropping the tank ( i will get a pic up in a bit).

I have sealant used inside the fuel cells of our MH-60R helo's, thats pure JP5 in there, and no issues, I am pretty sure it can handle modern gasolines Also was looking at doing the POR-15 gas tank internal cleaning/coating once it was all said and done,

-Mike

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I am the Guardian, I hate helos, everything leaks.......

What's the point of a custom tank? Just hold more fuel or...?

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19 Years young with a passion for all things old.

"Four doors for more....screaming passangers..(;"

"There's no replacement for displacement, but my \6 is still cooler than your V8"

more fuel, I like to take long trips just to go visit cool and unique places, and the extra fuel capacity is just added insurance that and in november I am getting restationed to NAS Keywest and its a hella drive to get inland from the island

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I am the Guardian, I hate helos, everything leaks.......

slice an dice !!!! Got 2 19 gallon tanks from a '95 and '97 mitsubishi 3000GGT's, intercooler piping and connectors and sender for $46 for anything



and the stock sender is a perfect fit for my aeromotive 340LPH pump

cut edges off tank






holes soldered up (the boneyard punches holes in their tanks, water checked, holds water fine


going out of town this weekend, will do more once i get back on sunday I will be trimming the edges and stitch welding and sealing from the back with more solder

-Mike

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I am the Guardian, I hate helos, everything leaks.......

The main issue with modern fuel is the ethanol. It soaks up water straight from the atmosphere, which increases the tendency to rust out metal fuel tanks and other components. Sealing the inside is definitely a good idea if you're welding on it. I've heard great things about POR-15. I tried using some cheaper fuel tank liner from Eastwood, but it was terrible. Started dissolving after a while and gummed everything up. Even with POR-15, be as careful as you can to follow the directions and get a clean, well-prepared surface. You don't want that stuff sloughing off inside the tank in the middle of a road trip.

Just curious, but have you already determined where and how you plan to mount this thing?

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Somehow I ended up owning three 1964 slant six A-bodies. I race one of them.
Escape Velocity Racing

of course, right where the stocker went It would have been nice to find another F/M/J tank where all i would have to do is just widen it, add depth, but atleast this gives me the opportunity to play around with tank size

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I am the Guardian, I hate helos, everything leaks.......

but then again i might use the other tank for an example, and modify the stock one, I did just get a 4'X8' sheet of 1/16th" thick mild steel not like I am not going to coat it any way lol

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I am the Guardian, I hate helos, everything leaks.......

I got some Red-Kote tank sealer from O'Reilly auto parts. I read that alcohol does not effect it. It seems to be popular for use in motorcycle tanks. The results may depend upon how well the tank is cleaned

I have soaked the tank in vinegar which loosened lots of crude. Now I am boiling the tank in hot soapy water. Lots of rusty water. At one time the tank looked clean, but more crud is now visible. I will use muriatic acid for the final metal prep but the vinegar seems to work well too. Its a good idea to get a new tank when you can.

If your making a tank, why not use stainless steel?

Sam

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not setup to weld stainless, and again this is a "best bang for the buck" tank build, I would personally do aluminium if i had the choice, and the means to do it

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I am the Guardian, I hate helos, everything leaks.......

How about a disconnectable aux. tank in the trunk...connect with a fitting running to the permanant tank.

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ifyoubegintothinkyou'relosingcontrol...it'salreadygone

That was my original plan, I may end up going back to that idea and using the newer tank as the trunk tank, being in the navy, I have gotten several large sizes of an fittings and hoses

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I am the Guardian, I hate helos, everything leaks.......