1951 Pontiac gas tank repair?

[Andy J]

I was cleaning the exterior of my gas tank with a wire wheel,taking off 70 years of road grime and dirt.The tank has no rust on it anywhere,except a dime-sized spot on the top of the tank.In the center of that rust spot is a 1/16" hole that rusted through from the outside.The inside of the tank is spotless,no rust or gunked-up residue anywhere.I mean shiny metal,like-new inside the tank.I thought of trying to weld the hole,but the metal is so thin that I'm afraid to try.I'm thinking of JB WELD that is made specifically for gas tanks.Have any of you had experiences trying a repair such as this?What do you think?  

 

I am just sick about this as the tank is like new except for the rusted through pin hole on top of the tank.If the hole were on the bottom,I'd probably cough up the $350-$500 for a new tank,but I'm trying to avoid that.

[Larry Schramm]

Go to a competent welder or radiator repair shop and they should be able to help you. 

 

If you want to try welding/soldering it yourself, fill the tank with water before you put a torch to the tank.  Should not be that hard to fix.

[Bloo]

I have tested JB weld in gas. It gets soft. No reason to replace the tank if the rest is solid. You could weld it, but in my opinion, soldering is the way. Follow @Larry Schramm's advice. A traditional radiator shop would make quick work of it, the problem is finding one. If the hole is more than a pinhole, you could solder a patch over it.

[Ben Bruce aka First Born]

Andy, I have told this story before, so please bear with me.  I owned and drove my own Semi Trucks for 40 years.  Twice a hole was punched in the BOTTOM OF a fuel tank.  First one, after letting it dry for weeks, while running on only one tank, was patched with JB Weld saturated steel wool. NEVER LEAKED.  Second, on a different truck was patched with JB Weld and later covered with fiber glass. NEVER LEAKED.  These tanks were about 24 inches deep so had a lot more weight on the patch from fuel than the top of your tank will have.  100,000 + miles per year.  Point being, what have you to lose.?

  For goodness sakes, many tanks are plastic today!   I realize some will yell " HACK" but I would be tempted to use a quarter size rubber patch with a metal screw through the center screwed into the hole.

 

  Putting my ear plugs in now.

 

  Ben

 

[F&J]

41 minutes ago, Bloo said:

I have tested JB weld in gas.

That's not a accurate way to test it, (if I recall correctly that you once said you put the product "into" a jar of gas).

 

I used the older original JB on my 1963 Allis Garden tractor tank, halfway up where the battery acid made a pinhole.  I cleaned it "good enough for solder" but chose to use JB.  That was maybe 8-10 years ago, so i know it works

 

I also used it on my daily driver 1932 with a 20 gallon 1920 Cadillac tank in the trunk.  Half way up, there is a riveted/soldered bracket that barely made a stain on the flat grey painted tank. It was never wet when i looked for an active leak, because the leak was so faint that it evaporated.  It only stunk the car up on hot days.  Again used the original JB, (not the newer JB that is made for gas that I only read about on here).  Anyways, after 1.5 years, that JB is still a perfect seal.

 

1 hour ago, Andy J said:

rust spot is a 1/16" hole that rusted through from the outside.The inside of the tank is spotless,no rust or gunked-up residue anywhere.I mean shiny metal,like-new inside the tank.I thought of trying to weld the hole,but the metal is so thin that I'm afraid to try.I'm thinking of JB WELD that is made specifically for gas tanks

Put a coarse sheet metal screw in it along with the new JB.  It will be fine.

 

If you weld or solder instead?  The metal area inside the tank at that repair will slightly rust. Just thought you'd like to know that.

 

People who run on about gluing something instead of "fixing it properly", have their heads in the sand.  All modern vehicle body crumple-zone panels are designed to be structurally glued together, and all repair shops must use the same during crash work.  Welding/brazing is not allowed.

Edited August 9, 2022 by F&J (see edit history)

[Rusty_OToole]

I would solder on a patch of galvanized steel or copper.

[plymouthcranbrook]

I have fixed gas tanks with fiberglass cloth many times. Never had a leak( in the same spot)

[rocketraider]

My mama and grandma swore by these things to repair everything short of the pressure cooker. Would probably repair your gas tank nicely if you could find them.

 

Trouble is they're collectible now.

[JFranklin]

9 minutes ago, rocketraider said:

 

My mama and grandma swore by these things to repair everything short of the pressure cooker. Would probably repair your gas tank nicely if you could find them.

 

Trouble is they're collectible now.

Here you go!  More where I found this.

 

https://www.ebay.com/itm/384910462954?chn=ps&_trkparms=ispr%3D1&amdata=enc%3A1jt-_HOFERX6FiMjLxRWgyg76&norover=1&mkevt=1&mkrid=711-213727-13078-0&mkcid=2&itemid=384910462954&targetid=4581046489808869&device=c&mktype=&googleloc=&poi=&campaignid=418640322&mkgroupid=1239149842233245&rlsatarget=pla-4581046489808869&abcId=9300602&merchantid=51291&msclkid=f71594a12f8f10e06e96f650fbab755bgo!   

Edited August 9, 2022 by JFranklin (see edit history)

[SMB]

Seal All will stop the leak and can be painted when dry.   I stopped a leak on the bottom of one of my tanks.   Available at any hardware store.

[Andy J]

First of all,I thank you all for your responses and suggestions. All replies were serious and I really appreciate that.Ben Bruce,your experiences were the most convincing,so I'm going with your suggestion. Like you said,I ain't got nothing to lose. If it works,great;if it doesn't I'll just buy another tank.

 

Hopefully I'll get this car running soon.I don't think I'll have it ready for Cruisin' the Coast,October 2,but it's not the end of the world.My wife and I have a couple of trips planned between now and then and the Southern Gospel group I play and sing with has several gigs coming up.It's all fun so I take it in stride.
 

[Akstraw]

For a 1/16 hole, you can fix with a sheet metal screw and a neoprene washer.  Or a sealed pop rivet.

 

[Oldtech]

I have an old electric soldering iron... likely from the 60's that works great for soldering tanks, but I don't know where you would find one nowadays.  Not a Weller type but an iron with a copper tip about 1/2' in Diameter. 

[Buick35]

I've been seeing more posts lately about J-B Weld,maby its because our vehicles are getting older and are having more issues.I just used some on a pin hole leak on my block in the water jacket and so far so good,it's a non pressurized system.I still might try it on my radiator top tank.I noticed after I topped it off with water right above the cooling fins it's leaking a little.I see they make a j-b weld for water leaks. I think it would be hard to solder unless I pull the radiator on my 35 Buick.

[Frank DuVal]

On 8/9/2022 at 10:58 PM, Oldtech said:

I have an old electric soldering iron... likely from the 60's that works great for soldering tanks, but I don't know where you would find one nowadays.  Not a Weller type but an iron with a copper tip about 1/2' in Diameter. 

That is what I use, the American Beauty 100 watt. Clean the area and make a small copper patch that covers the hole. Flux the steel then tin it (that means heat the metal and apply solder very thin). Tin a side of the copper patch. Place the patch over the hole and  heat the patch, applying solder as needed. I use copper flashing (or gutter*).

 

No need for ANY FLAME!

 

I'm crazy, but I have used this iron to close holes in leaking tanks with the iron unplugged after it is hot. Not with the copper patch, just leading over the pinhole. Sometimes also a short #4 sheet metal screw (sanded shinny to remove plating) in the pinhole. Takes several tries as the gasoline cools the joint real quick. I said I was crazy! DO NOT ATTEMPT ON MY ADVICE! But when the car was leaking gasoline on my collision shop (and Corvair mechanical) floor one does what crazy stunts can be done with the tools at hand. 

 

*gutter. One day at the shop, on busy Broad Street, I heard a clatter as a pick up truck passing by with metal for recycling dropped a 10 foot section of green patina bent gutter in the road. He didn't stop. I ran out and picked it up to prevent others from having tire trouble running over it. Made many a patch and still have 5 feet left.