Leaking gas tank

[Mad Mac]

The gas tank on my 1929 RPU has a slight leak where the steering column clamps onto the bottom of the tank. I am going to remove the tank and mend the leak, but I am not sure how to do that. What is the best way? I tried to block it with JB Weld but that did not work.

 

[BRENT in 10-uh-C]

The gas tank on my 1929 RPU has a slight leak where the steering column clamps onto the bottom of the tank. I am going to remove the tank and mend the leak, but I am not sure how to do that. What is the best way? I tried to block it with JB Weld but that did not work.

Please take a moment to define "best way" first.

I am sure you understand there are 'best ways' to repair it permanently, -and there are 'best ways' to band-aid or patch it. Specifically, which are you leaning towards? I/we can likely give you the correct advice once we know what your true intentions are.

 

[Marshall V. Daut]

I've posted this before and it works. I recently fixed a friend's leaking 1930 tank this way.
First, drain the gas tank and remove the gas cap. Allow the tank to dry this way for a couple days. This lets the gas at the bottom of the tank evaporate. Take lacquer thinner or carb cleaner and thoroughly clean and dry around the bracket riveted to the gas tank. Do this ALL the way around the bracket's base, front and back. Then buy the two-part MARINE epoxy, no other kind of epoxy. Only MARINE epoxy is impervious to gasoline. Mix and knead the epoxy until it is a consistent dark gray color. Roll a thin bead of this between your hands' palms into a snake. Then carefully press this bead all around the edges of the bracket, all four sides. Be sure to push it inwards to fill the crack. You are sealing the entire bracket and also re-enforcing it against future leaks. Allow this first bead to cure. A day or two later add another bead. This one you can pay more attention to how it looks than the first bead, which was more of a filler layer. Wet your fingers with water to smooth out the second bead and to keep the epoxy from sticking to your skin. Make the bead look smooth all around the bracket. Once this cures, use touch-up paint that approximates the color of your gas tank. And don't use the steering wheel to pull yourself in and out of the car! That's what stresses this bracket and causes it to leak in the first place.
Of course, applying silver solder around the bracket's base with an acetylene torch would be the preferred repair, but it can be dicey using a flame around a gas tank, even if it has been drained and allowed to air dry. Plus, you will burn off a ton of paint from the gas tank. Try my Marine epoxy procedure and your leak will be fixed. If for some reason this doesn't work (shame on YOU!!!), you're only out less than $7.00 and two days' time, mostly spent allowing the MARINE epoxy to cure.
Marshall

 

[nkaminar]

Marshall, please supply the source for your Marine epoxy and details as to who makes it, etc. When I google Marine epoxy I get a number of choices.

Any hot work on a fuel tank can be done by putting dry ice in the tank and then putting the cap on. The dry ice will fill the tank with non-combustible carbon dioxide. Argon also works.

 

[Marshall V. Daut]

I bought the Marine Epoxy at a local True Value hardware store. I didn't save the cardboard packing, so I don't recall which Marine Epoxy I used. I recall that the main heading and front printing were blue, if that helps at all. Read the labels on your Marine epoxy choices and see if one specifically states it is gas-resistant, although I would imagine any flavor of Marine epoxy will work.
25 years ago I somehow managed to drill a hole in the side of a gas tank mounted in a roadster cowl. I was "fixing" something else in that area and the drill went in too deeply. Anyway, the hole was low in the tank's side, so gas immediately leaked out. I drained the tank and wadded up some Marine epoxy and plugged the hole. After curing, no more leak. That was in 2001 and as a far as I know as of 5 years ago, the leak never came back. 'Made me a believer in Marine epoxy!
By the way, if your steering column all of a sudden starts to leak all over your pants on a tour, long distance drive or when you are away from home, simply rub a bar of soap over the leaking area and the leak will stop for a while. I can't explain chemically why this works, but it does. It is by no means a permanent repair, but it will get you home before your pants and shoes become saturated with gas!
Marshall

 

[JayJay]

Marshall, please supply the source for your Marine epoxy and details as to who makes it, etc. When I google Marine epoxy I get a number of choices.

Any hot work on a fuel tank can be done by putting dry ice in the tank and then putting the cap on. The dry ice will fill the tank with non-combustible carbon dioxide. Argon also works.

Yes inert gas can be used to inert the tank. A far safer way is to drain and dry the tank as Marshall suggests, tape off the fuel gauge and outlet holes, fill with water, cap it, invert it and then go at it with heat. You are trying to displace enough oxygen that you no longer have a combustible mixture, and a tank full of water is the safest displacement method.

 

[Synchro909]

In adition to what Marshall said, once you have stopped the leak, instal one of the steering column support brackets like Henry did in 1931. If you can't buy one, make one. They are very easy to make. I use the piece of the original bracket I cut off the borrom of the tank as part of my new one and the same clamp underneath. The brackets are held by the bolts up behind the dash, taking the entire stress off the tank. I use a piece of 3 mm (1/8") steel and include provision for my gauges and a switch or two.
You will never have that problem again.

 

[Marshall V. Daut]

This is how that 1930 Roadster with a leaking steering column bracket ended up looking after adding the late 1931 upper support, as Synchro909 recommends. A piece of fender welt was later placed between the old bracket and the steering column jacket to fill the slight gap and to cushion against any vibration noise. It also gives the area a more finished look. I supposed a lower clamp bracket could be added underneath the old column support bracket, but it's not really needed.
Marshall

 

[Ray in La Mesa]

The tank on our farm truck yardarm has a home made '31 style bracket made using a connecting rod with the big end clamped around the steering column welded to a small bracket bolted to the cross rail.

 

[Marshall V. Daut]

Here's another thought: Painting the old gas tank bracket black might create the optical illusion that the bracket is no longer there. Or, add the missing lower clamp and paint it body color. Then it will look as if there are two steering column supports, which in fact there are.
Marshall

 

[Mad Mac]

Please take a moment to define "best way"

Thanks Brent, the "best way" for me is a permanent fix. I guess that involves removing the tank and either soldering or braising the bracket, after filling the tank with water or C02. Any tips on soldering compared with braising or maybe some other process?

I already fitted the special dash bracket but that was too late to avoid the leak.

 

[w.michael]

Marshall, Do you have to remove all the paint around the base before applying the epoxy?

W. Michael

 

[Marshall V. Daut]

"Do you have to remove all the paint around the base before applying the epoxy?"

I did scrape away paint right in the seam between the bracket and the gas tank, but not from the surrounding area. A small flat blade screwdriver works well to dislodge paint in this tight area, followed by a few blasts of compressed air. The leaked gasoline has turned paint in this seam to flakes and loose debris that will not hold the epoxy well. So, it has to go. You don't need a thick "snake" of epoxy to seal the crack. By pushing the first layer of epoxy in as far as you can, the crack will mostly likely be sealed. The second bead just ensures the crack is covered and also provides a more finished look than leaving the necessarily rough-looking texture from the first bead exposed. By keeping your fingertips wet, you can nicely smooth out the second bead, much like sculpturing clay. The smoother the second bead is, the less noticeable it will be that a repair has been made there, especially when touched up with lower body color paint.
Marshall

 

[nkaminar]

Marshall, I found two paste type marine epoxies at True Value. Do either of these look like the one you used?

 

[Marshall V. Daut]

No. Neither looks familiar. I'll ask my friend to dig out the receipt for the Marine epoxy I bought to fix his gas tank. Give me a day or two.
M.

 

[jb-ob]

I've successfully used JB Weld 'Tank Weld'.

Understand the root cause of your leaking gas tank. After 90 years of yanking on the steering wheel to hoist yourself into the front seat, the tank bracket has become loose from it's rivets & it's solder joint has cracked.

All these 'silly putties' are a temp fix until you adjust your 'entrance' differently.

 

[Marshall V. Daut]

Yup, right-o, Jim, as always. That poor steering column bracket can withstand only so much anti-force tugging, which causes the bracket to break loose from the gas tank and create leaking. Even Ford recognized the problem by 1931 (finally after three years!) and introduced the upper steering column bracket to reduce the strain caused by using the steering wheel and column for entry and egress. I believe we are free of most of the blame and damage we see today in this area. It was preordained by the time we showed up at the party. Generations of previous owners loaded the gun. As latter-day owners, we only pulled the trigger and supplied the proverbial "last nail" in the coffin that created the VERY common steering column leak in 2026.
No matter who's to blame (who cares anyway?), several contributors have offered viable recommendations here ranging from temporary to so-called "permanent solutions. (Is there such a thing??? ) With what has been suggested so far, a number of repairs will solve the problem. Once again, there is more than one way to skin a cat in restoration terms.
Marshall

 

[German guy]

Thanks a million. I have had this problem with my 1939 Tudor since I bought it 3 years ago. The leak is slight...but the slight gas dampness at the bracket and the rare drip onto the floor is less than optimal. I have tried liquid solder, various fillers, normal epoxy, etc. I really would rather not pull the tank out and send it out for repair. I will try your suggestion this winter when my 'Henry' takes his winter nap.

 

[rotorwrench]

These poor old model A tanks have been around for 94 to 98 years and they ain't getting better as more time passes. Those steering column brackets were riveted in along with an internal reinforcement plate. Even with the plate, cracks can form and rivets get loose. You can imagine a little kid climbing on there to get a rotation thrill. I did that when I was a little kid, not knowing any better. It's the only handle other than the door to get a hold of when getting into the driver's seat so they move a little each time a big load is applied. The metal is pretty thick (near 1/16") but all metal fatigues and corrodes over time. Opening the tank up is the only way to gain access in there. I've opened a few so I know how much fun it is to get them welded back together It's not a fun chore to do a tank and get it to last a long time. I cut them right on the edge of the roller weld seam all the way around.

There is an epoxy available that is claimed to be a fuel proof sealer but I haven't tried it yet. The stuff is called Max GRE for gas resistant epoxy. I'm going to try in on my next tank job to see if it works. I'm not a giant fan of the latex based stuff. I just thank God that I can still get ethanol free fuel here in TX.

 

[Marshall V. Daut]

I took a photo of the Marine epoxy I used to fix a friend's leaking gas tank. It's actually called Marine Weld. My wife and I were just at a local hardware store, so that was the perfect opportunity to document the type of Marine epoxy that was successful.
Marshall