Soldering fuel tank

[farmer boy]

Will a soldering iron ignite gas fumes? I have a tank with a few small pin holes on the top and I want to put a bit of solder on it to seal it up. If I run argon into the tank for ten minutes(very slow and unregulated) will I be safe to solder it? Not emptied, just a bit or gas in the bottom, but with a steady flow of C25. I don't really want to introduce water into the tank on purpose, afraid of worse rust problems. It's bad enough to start with. Don't really want to replace the tank either, $400+ and can't find much for used.

 

[supergrumpy]

if you want to solder with electric soldering iron wou will need pretty high wattage to get solder to melt and stick, make sure the metal is very clean and use good old time lead/tin solder if you have some

I used propane torch with soldering tip, said a very sincere prayer before I started, worked just fine

on another tank I tried the chemical gas tank repair stuff at NAPA, if you don't have vibrations in the area it will probably work, if pin holes are on top of the tank it will probably work, on an underside repair I had seepage problems after a while

oh, if you drop the repaired tank onto something hard after you do the repair it will not work

 

[bison]

Get a can of por-15,it'll seal thank forever.

 

[MSD]

If you can find an old soldiering iron, heat it up away from the tank and it should be hot enough to do pin holes. Make sure it is good and clean and shiny where you are going to soldier.

 

[hanovertom]

I have soldered with a torch while purging with co2, make sure its as dry as possibe

 

[Anonymous-0]

C25 isn't what you use. You need straight CO2. I wouldn't be putting anything hot around a gas tank without taking serious safety precautions. Getting the tank steamed is the best thing to do. You could use a CO2 fire extinguisher. If you run water through the tank, you can always dry it with an air blow gun or a hair dryer.

 

[Goose]

I blew up a tank once, and I'd just as soon not do it again.

It's my current practice that when someone wants to introduce artificial heat to a gas tank, I stand about 100 yards away with my fingers in my ears.

That being said, before I created my own Hiroshima, I once watched a guy do open flame soldering on a sprint car tank by putting a flexible hose off the tailpipe on his pickup into the filler opening on the tank. His theory was that by idling the pickup for 15 minutes the exhaust evacuated all the gas fumes from the tank. It worked for him. However, a sprint car tank would have had methanol alcohol in it. Don't know how that compares to gasoline.

Best is to have a radiator shop hot tank it. Or, if looks isn't a factor, I've fixed tanks by roughing the surface with a sander and applying several layers of fiberglass.

 

[David G]

Take the tank to the carwash and clean out good with hot soapy water, then blow it out dry. Blow the tank out good right before you torch it, and you will be fine.

It takes a combustible mixture to explode. It doesn't matter if there is too much O2 or CO2.

 

[RayP(MI)]

I once welded a patch on a gas tank with a wire welder. Emptied tank, off vehicle, dumped it out as thoroughly as possible. Then put a muffin fan out of a computer over the port in the center where the intake & fuel guage went in. Ran it overnight. Next morning I souldn't even smell gasoline fumes. Welded it, and kept filling with water to check for leaks. once I got it leak free, emptied it out best I could, ran fan again to dry water out.

 

[farmboyWI]

I've been told acetone absorbs water, if that helps any. Be careful.

 

[36 Coupe]

An electric soldering iron will work fine.JB Weld will do the job.Look in used tool shops for big soldering irons.New ones are expensive.Solder guns wont do the job.

 

[Anonymous-0]

I was soldering a tank once and come across a nickle[5 cents] in a previous repair by someone else. It gave me the idea to use a piece of copper sheet to fill over several small holes at once instead of trying to patch each hole.Flowed the solder over the copper patch.

 

[Inno]

I soldered the outlet of my tractor's gas tank with a propane torch. I had cleaned the tank thoroughly of all gasoline and rinsed numerous times with soapy water. I was still getting little puffs every now and then as I was heating from around the outlet. Probably not the best thing to do.
In hindsight I probably should have tried my big soldering gun. It would have taken longer but would have been safer than an open flame.
Having said that, it no longer seeps gas and that was over a year ago and the tractor gets pretty much weekly use.

 

[smallercrawler]

Another way I"ve seen it done it is with a soldering "copper". It is a large, heavy soldering iron that is not self heated, but is heated by a small stove or torch at a REMOTE location thus minimnizing the risk of fire/etc.( no live torch flame or potential of sparks from electric iron cord connections). A large 2lb. one will hold a lot of heat for a very long time. I think they were originally used by tin/copper roofers and gutter installers.

 

[Anonymous-0]

The local weld shop has repaired several gas tanks by piping engine exhaust gas into the fill spout for roughly ten minutes before brazing and they are all still alive. Keep the exhaust gas flowing during the repair. Can't explode if there isn't oxygen.

 

[LenND]

Years ago I had a 57 Ford car that I used in construction. Couldn't keep the front of tank from getting leaks. Took it to local welding, machine shop. He sent me to nearest gas station to fill tank completely full. Brought it back and he put it on the hoist and soldered a piece of copper across the front of tank. The only think that blows is the gas fumes. Gas itself will not blow-burn yes.

 

[rlp in Co.]

That is the method that I use. I run a pipe from a small engine exhaust into the tank for at least 15 minutes. Don't use a diesel engine! A diesel has mucho excess oxygen in the exhaust. I just welded two aluminum tanks. I don't even empty the gas or diesel out. The cleaning with water or steam is a dangerous method. There can be gas that will seep out of the cracks and it only takes a drop to cause an explosion. Carbon dioxide or argon will work just as well, only very expensive.

 

[Anonymous-0]

Get some of the putty from auto parts store specifically made for fuel tanks. Incidentially it is manufactured in U.S. much easier.