gas tank sodering

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jimjimjimmy

lobsterman
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I gotta solder a nipple in a used gas tank I was thinking of putting a hose in it hooked to a exhaust of a car and filling it with carbon monoxide what do you think?
 
If you have a CO2 source that would be a lot "More certain." (I just use straight CO2 on my MIG)

If you know how, I'd use high temp silver braze (many improperly call it silver solder, nowadays to be confused with the lead free low temp stuff)
 
If you have a CO2 source that would be a lot "More certain." (I just use straight CO2 on my MIG)

If you know how, I'd use high temp silver braze (many improperly call it silver solder, nowadays to be confused with the lead free low temp stuff)
I buy rolls of bi metal saw blade and that's what I use to join it together .
 
yea I know how you guys like nipples :jocolor:

but can this same method be used to fix a small hole in a gas tank ....my coronet wagon has a small hole on the gas tank ...looks like something chafed the hole there ...I think from something that was there before...like trailer apparatus or something that is not there anymore......but either way I need to fix it because its a really rare tank unique to wagons and worth trying to save.....but I wasn't sure how to approach the repair
 
yea I know how you guys like nipples :jocolor:

but can this same method be used to fix a small hole in a gas tank ....my coronet wagon has a small hole on the gas tank ...looks like something chafed the hole there ...I think from something that was there before...like trailer apparatus or something that is not there anymore......but either way I need to fix it because its a really rare tank unique to wagons and worth trying to save.....but I wasn't sure how to approach the repair

I've used this in the past to patch hard to find tanks.

http://www.jbweld.com/product/j-b-waterweld/


Used it to seal the drain plug on the bottom of the tank in my D50, which was pouring out gas. I mixed up some of that, crammed it around the leaking plug and forgot about it for years. When I removed that tank, I tried to pull the drain plug to empty the tank. Couldn't get the plug to budge with a 1/2" Drive Ratchet and a 2' Cheater Pipe.
 
Rani unless you are CERTAIN that you take good precautions, this might not end well.

Obviously the safest way would be to have the tank repaired by a pro, like a radiator guy who has and will do so

Otherwise, the safest would be to pull the tank and fill nearly full of water, leaving just a small cavity where you need to make the repair.

When I installed the return fitting in my car, I did this..................

Drained, emptied the tank. Pulled the vent line loose up in the filler neck and extended it out away from the car

With no other outlets except the open cap, I plumbed the CO2 into the outlet on the sender and ran CO2 for several minutes. Used the CO2 / regulator right off the MIG

When "I figgured" it was about flooded, I installed the fuel cap and LIT the vent line fumes at the extension away from the car. When the flame went out I knew I was close, and "gave" it about another 2 minutes worth of CO2, leaving it flow while brazing.
 
rani im not sure about filling a hole with silver braze but you could make the hole round and braze in a plug and you could use it for a drain if ever needed.
 
If you don't have a cylinder of CO2, buy some dry ice at the grocery store. You can use that with a water fill, indeed the water will make it outgas faster (Halloween witch'es brew). I successfully soldered a galvanized steel patch to my 66 Newport tank using a propane torch. I used "plumber's solder" (ca. 1980's).
 
Ditto water...can do CO2 first, let sit, then fill w/h2o...that's what guys around here do to weld on propane tanks that are being converted...never had a problem.
 
I narrow a tank with a mig welder years back. I used water. I then cut the tank and rinced it again. several days later I held a propane torch into the cut open tank. It lit and burned for several minutes.

I just split a 3 peice tractor tank for clean out and repair. I filled the tank with argon gas like you would do a roll cage. It weld perfect.

I added some extra **** for enjoyment
 

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Just take it to a radiator shop and have it "boiled out" and repaired. It's not that expensive, it'll clean all the rust and crud out of the tank, and you'll have the piece of mind knowing that it was done right. Not only that, any reputable shop will pressure test the results, so you'll know it wont leak too.

For the OP, exhaust fumes contain A LOT more than just C02, including lots of unburned hydrocarbons (fuel!) and CO which can still ignite. Hooking a gas tank to a tailpipe and welding on it is a great way to end up in the ER.

I can MIG, TIG, torch weld and braze just about anything with the machines I have in my shop. And the one thing I don't mess with is fuel tanks- unless they just came back from the radiator shop. Not worth the hassle or the risk.
 
I just put some dawn dish soap in the tank and fill about 1/4 with water and slosh around for a couple of minutes.

After that I stick a water hose in it and let it run for about 10 minutes.

I have the best results using an old time Oxygen/acc setup using just steel rod, and never had any to leak afterwards.

Done 8 tanks this way and had zero problems
 
well I stuck a hose in my Honda car exhaust to the gas tank run it for 5 min . I used silver braze . and no there was no boom . I have done many this way and feel very safe doing so.
 
if your a dummy
Well ya! I am not saying anybody here would have a problem. I hung out with a couple guys in my youth and I admit there was a lot of beer consumed. The had a old Suzuki with a dent in gas tank. The plan seal the tank and put air pressure on it and put a rose bud on the torch and a little heat on the tank. Well I am sure you can see whats coming, can you say BOOM. They didn't get hurt except for ears ringing and the tank look like a large sea turtle shell laying on the ground. So bad things can happen with a torch and a gas tank LOL. :eek:ops:
 
well I stuck a hose in my Honda car exhaust to the gas tank run it for 5 min . I used silver braze . and no there was no boom . I have done many this way and feel very safe doing so.

That is exactly like the old school pros do it. Super safe.
 
well I stuck a hose in my Honda car exhaust to the gas tank run it for 5 min . I used silver braze . and no there was no boom . I have done many this way and feel very safe doing so.

That is exactly like the old school pros do it. Super safe.

Well, I'm glad you guys feel safe doing it that way, and that you haven't managed to blow yourselves up. But just because you did it and didn't kill yourself doesn't mean you can't blow yourself up doing it that way.

Automobile exhaust is combustible, plain and simple. This can be especially true for older vehicles if not properly tuned. Carbon monoxide, also in exhaust fumes, has an ignition temperature of about 1,200 degrees F and has an explosive range from 12.5-74.2%. Yes, the ignition temperature is significantly higher than the gasoline vapor you're displacing, but it still has an ignition temperature, and it's still less than what you can create welding. This also assumes you're actually displacing all of the gasoline vapors in the tank, which- A. you aren't doing 100%, and B. you have no way of testing to see if you are.

Can I tell you what the odds are that you'll reach the correct concentration of exhaust gasses and enter the flammability range? No, I can't. It's probably pretty unlikely that you'll enter the flammability range while you're above the ignition temperature too. But if you did, you definitely wouldn't be the first person to have blown themselves up welding on a gas tank with a tailpipe hooked up to it. And I'm sure you wouldn't be the last, either.
 
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