Fuel System: Gas tank patching with JB weld

[Jeff_H]

This is for a brand X, but could apply to a stude as well, so I am posting it here....

Got a tank with about 1/2 dozen pin holes in a circular depression area on the top of the tank surrounding the tank sender port. The area is pitted from rust and its rusted from the outside in. I'd noticed the tank leaking the last time it was filled but then it quit once the level was lower.

I am thinking of applying a coating of JB weld over the pin holes and the pitted area. Should I put something over it, like a sheet of galvanized metal or fiberglass mat?

When I found the first 2 pin holes, I was going to put some JB weld on the hole and run a sheet metal screw into it, but after finding several more and the amount of pitting here, I don't think that is doable as several are too close together.

I've power wire brushed it to bare metal and will clean the surface with acetone before putting the epoxy on. The concern is of course that it pops off or cracks.

Any tips or experience with this?

[sweetolbob]

This is just my personal opinion as I've never used epoxy on a gas tank but my experience with it in other locations where solvents are present would lead me to not use it is gasoline exposed areas. I could argue that with it keying through the holes it would be permanent but I'd want to coat the tank inside to lessen the exposure. Personally, before I'd go through all that effort, I'd cut out the offending area and weld in a new section.

If you want to check the efficacy of JB Weld in gasoline. Cure up a test strip of JB on sheet metal and put it in a jar of gasoline for a month or so and see how strong the bond is then.

BTW, the issue is not the epoxies resistance to gasoline, it's the interfacial strength in the presence of a chemical agent.

Your tank, your choice as others have said. Bob

[GinettaG12P]

Brush on sloshing sealer.

[5brown1]

Jeff,
Take a look at Seal All. My hardware guy made me aware of the product when he told me he watched a guy seal up a leaking (at the time) motorcycle gas tank.
I use it on the drain plug area of my tank which was seeping. It stopped the seeping. This was after an unsuccessful attempt to seal it with the epoxy stuff you get at the auto parts stores. Only problem is, it is cheap which will lead one to assume it cannot be any good. It is on sale everywhere. You can also apply multiple coats. Great for lots of uses.

http://www.eclecticproducts.com/sealall.htm

Good luck,
Steve

[Chicken Hawk]

When I got my truck car hauler back in the 1980's the gas tank had several pin holes in the bottom. I cleaned it good and put JB Weld on it and they are still holding today.

Ted

[JoeHall]

When I got my truck car hauler back in the 1980's the gas tank had several pin holes in the bottom. I cleaned it good and put JB Weld on it and they are still holding today.

Ted

I had a similar experience Ted, with JB Weld in repairing a tank at the junction where the "straw" comes into the lower left, front corner, on a GT. It had came loose inside the tank and was just flopping around. I drained the tank as best I could, then jacked the driver side up high enough for the remaining gas to go the the other side of the tank. Then used JB Weld; allowed it to dry overnight, then applied more the next, then again the next. It was still holding a good ten years later, when I swapped the tank out for other reasons.

I prefer the original, slow drying JB Weld because it flows out better.

[52-fan]

Jeff,
Take a look at Seal All. My hardware guy made me aware of the product when he told me he watched a guy seal up a leaking (at the time) motorcycle gas tank.
I use it on the drain plug area of my tank which was seeping. It stopped the seeping. This was after an unsuccessful attempt to seal it with the epoxy stuff you get at the auto parts stores. Only problem is, it is cheap which will lead one to assume it cannot be any good. It is on sale everywhere. You can also apply multiple coats. Great for lots of uses.

http://www.eclecticproducts.com/sealall.htm

Good luck,
Steve

My dad used Seal-All to patch a small leak from dragging the gas tank on a rock while we were on vacation. The repair was supposed to just get us home, but it was still holding 10 years later.

[rockne10]

There are a couple different JBWeld products so be certain it is labeled to resist fuel.
There are also products from Permatex designed specifically for the purpose you intend.

https://www.google.com/?gws_rd=ssl#q=permatex+gas+tank+sealer

[Jeff_H]

Thanks,

I should add some back story here. I can get a new tank for about $120 (seems cheap) but then would need to transfer the fuel pump and senders to the new tank. From the looks of the those being corroded in place (and not leaking) I can see this getting into the $250 range in a hurry for new ones. This car is a total rust bucket (and I don't call it this lightly, being from the rust belt and all, where the definition of a rust bucket varies from the south) and I have already spent too much $$ (and my valuable time better spent elsewhere) on it and its not yet doing its last winter. So, trying to limit my outlay as this is really going to be its last winter assuming it gets out of my garage. I have joked about this thing going "one more winter" for like the last 10yrs but its gotten to the point now that its pretty serious. I should have called it quits when the brakes went out in 2013.

So if some putty on the tank holds up for 6mo or so, I am gold I think.

[mapman]

I used JB weld on a Lark gas tank that had been scraped on a rock and had a good sized dent. It lasted years until I sold it. I pointed it out to the buyer and he had no problem with it since he had done it before too.
Rob

[wittsend]

I converted a carburetor car to an EFI engine. I needed a fuel return and didn't want to use the vent line like most did. I elected to drill a hole in the fuel sender housing and then solder a tube into the hole. That all went well except the nylon seal for the wire melted when the tube was soldered. I put a healthy dose of JB Weld over the nylon seal/steel plate. The tank is configured such that the sender is immersed in gas at least 75% of the time. Six years now and nothing is leaking.

[njonkman]

JB Weld is a great product. It can withstand high heat as well as chemicals and high torque. I used to sell the product when it first came out. They gave us a pair of intake engine valves stuck together face to face with JB Weld. You could stick one in a vice and pound the other one until they formed a U but they would not break apart. They also claimed you could repair tractor wheel splines with it at drill and machine it. I have used both Seal all and JB Weld for gas tank repair, the first for probably over 50 years. Now I stop the leak with Seal All and then coat it over with JB Weld. Gas can be pouring out and just dabbing the Seal All into the hole you can stop the leak.
I also used JB Weld to repair my 56 Champion crankshaft. There were a number of pits in the rear seal journal which a crank grinder could not get at and the seal had leaked so bad that the whole bottom of the car was oiled. So I put the crank in my large metal lathe and skimmed a bit of the journal. Cleaned it real good with lacquer thinners and applied JB Weld. Then I tried machining it down to speck. I found as I was getting down to speck I was peeling it off. So ended up machining the journal down about 1/32 inch under size and that worked. It machined down fine and polished up beautifully. We ran it all this past summer and not a drop of oil. The JB Weld will not pit from moister as the steel would so feel very confident in it as the best way to repair that problem.
Nick