I'll say this much, when tanker trucks that previously had diesel, gas, lng or cng get cracks, leaks or damaged they're getting repaired period. They're not buying a new tanker ,they're fixing the damage. It can be done.

I worked at a place that repaired lng/cng tankers. Look up how explosive those are.

If he is retarded, then there are a lot of successful retarded hot rodders and fabricators out there. Most mustangs get sumps welded in when they start getting faster than the stock style pump will support. Lots of low budget guys do it themselves. They don't buy new tanks and they don't tig weld them. They mig weld used tanks just like this guy did. And unlike his, they are welding where fuel leaks are more likely (under the level of fuel) Most all of them work fine. They don't re-galvanize them and they don't MPI them. Tig welds can look good and suck too, so don't get all judgemental about looks. And nobody pressure tests them because it's not a pressure vessel. Pressure testing a fuel tank would actually be quite dangerous.

Water and electricity are fine the way he is using it. Minimal air/fuel mix in the tank is the goal and water does it just as well as CO2 and Argon, it's just harder to work with.

Don't be a fabricator snob. This is hot rodding, there are many ways to do things if your smart about it. If your not, the tank explodes and natural selection does it's job.

I've had two tanks welded on, and both times the shop filled them both with water, and welded away. I did the clean out work, as Greg talked about, myself, before I took it to them.
I wasn't confident in my welding skills at the time, so I used a local shop.

First I am definitely not a fabricator snob I mentioned that so some people know that I do have knowledge.
Second yes there are lots of people who do weld used tanks with success, that by no means that he should be telling someone else who doesn't quite know what to do or how to do it, ways to weld and possibly hurt himself
Third there were previous suggestions on much safer ways to do this eg. Try local shops, purge with argon,
Fourth clearly you aren't thinking correctly either a fuel tank IS a pressure vessel. Iill let you figure out that one
Fifth anyone who has welded anything galvanized will know how it can "pop" and "spit" unless you use a galvanizing wire which quite often is expensive and not easy to find.
I absolutely welcome hot rodding and everything which comes with it, I do have a problem with things when there is a solid 50/50 chance of someone getting hurt over a couple hundred dollars and some questionable advice

Kinda bummed out that this thread turned to personal insults. Not cool, especially if you consider yourself a professional fabricator by trade. Any how... Ive got a lot of good info here. I think that I will give this a shot when the time comes. I'm all but settled on the dish soap method. I'm probably smart enough to run the tig near a tank full of water and not electrocute myself.

I should not have called him retarded...i was rude and wrong, it really gets me though when people open the opportunity to hurt themselves for absolutely no reason other then questionable advice. Having said that I think most people also missed something I should have stated but I thought it was obvious. If someone has a welder and the ability to weld the tank.....then why in gods name would you not purge the tank with argon. I have welded probably 15-20 transport truck tanks after road salt has been trapped by the straps. A simple aluminum strip is welded in place and then pressure test the tank at 10 psi with a soapy water solution. Back to the purging...the tanks were purge with a tank of argon, regulator and, hose. Dial the regulator down jam the hose in the tank and open the argon tank,after a few minutes the argon will push out the oxygen when possible just continue to let the argon flow while welding as it can also aid in weld penitration. If you can't then tape off the opening and weld away
Good luck and please play safe

Great tips, very helpful. Thank you. I understand your frustration. Thanks for clearing the air.

Rob

Im not saying it stupid, turbo timing, dangerous or a waste of time to do. Its just so much easier for me to buy a new tank and ones that are already converted.

I have modded a few tanks in the past, you have to take it down, clean it out, prep it, prep i again, weld it up, pressure test and repair if the weld didn't hold. Sound like an easy afternoon, sure but you still have that dented scruffed up old gas tank.

For less than 4 hours of labor time you can have a new tank that is sealed right and does what its supposed to do... and it looks new. But....if they are not available for your car then have at it. Dry ice in the tank and go.

I'm well aware of the fumes from welding galvanized metal. I did it in a ventilated area and had no problems.

The air space is minimal. Maybe what little fumes are in there could cause a problem but nothing like an empty tank full of fumes. Nothing happened so oh well.

I know the welds look bad. I never said they didn't. The piece from the Camaro tank was much thinner and it was hard to make tacks without it just making a bigger gap. I'm sure a pro could do it better.

I pressurized the tank and used soapy water to find pin holes.

People like you really need to calm the heck down. I never said I was a professional or sharing my profound knowledge. The point of what I did was to make my truck run with what I had on hand until I decide on a better tank. It's not professional quality but it works. The point of sharing it was to show that I welded on a tank with no catastrophic damage done, not to show what a pro gas tank welder I am.

not baggin on you but your debating safety. whats safer? welding on a cleaned out tank that previously had fuel in it or having a 16 gallon fuel tank with potenial for leaking welds? :sarcasm_smiley: