Topic: welding on a fuel tank
in Forum: General Non-Vette Discussion
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As many know welding on a fuel tank is something that can go drastically wrong. I find myself needing to add a sump to a tank on a car Im building and not sure of how to handle this task. Im working on an older dodge, 66 dart, and I plan on doing some drag racing a few times a year. For this I should have a sump, so the need to drill the tank then weld a sump onto the bottom has confronted me. Has anyone here done anything like this and what safety precautions did you follow.
I know the safest way to add a sump is to buy a fuel cell with a sump already on it, but that means losing my spare tire well and I dont want to do that as I plan on driving on the street and I want to carry a spare. I know we are vette owners here but many have other cars so Im sure others here have crossed this situation before.
As always Thanks in advance for your suggestions and comments.
Rodney
I know the safest way to add a sump is to buy a fuel cell with a sump already on it, but that means losing my spare tire well and I dont want to do that as I plan on driving on the street and I want to carry a spare. I know we are vette owners here but many have other cars so Im sure others here have crossed this situation before.
As always Thanks in advance for your suggestions and comments.
Rodney
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Lifetime MemberLemon Grove, CA - USA
Joined: 10/17/2007
Posts: 2041
Vette(s): 1982 C3 Collectors Edition 44000 miles, sat in the sun most of its life, My wife purchased it for me for Father's Day in 2007 from her girlfriend that had it for 19 years. It is on the road again. I'm retired but it is now my daily driver.
I had a hole taken care of on one of my cars a long time ago. The guy that did it said it was not a big issue working on gas tanks. He said getting it cleaned out and then it was almost like welding any other thin metal tank.
He was not overly concerned but that could have been because of experience or lack of experience. I was not around when he did it just dropped it off and picked it up.
I know this is not much help except to keep it fresh another day I personally cannot weld anything.
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The main danger is fuel vapors. Even if the tank has been empty for a while, vapors still remain, and can be deadly if ignited. Lost a friend years ago from a tank explosion. Working in a salvage yard, and he was dragging(by hand) a tank across the yard when it hit a rock or something that sparked. Tank exploded. Came out of a car that had been sitting in the yard for years, and the tank was completely dry....
I've seen guys weld on tanks that had raw fuel leaking out of them, too. It's the VAPORS that are most dangerous, not the liquid fuel. My advice is to clean the tank many times with solvent(or kerosene), and water. Air dry it for days/weeks. Then have someone else do that work....
Joel Adams
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Lifetime MemberLemon Grove, CA - USA
Joined: 10/17/2007
Posts: 2041
Vette(s): 1982 C3 Collectors Edition 44000 miles, sat in the sun most of its life, My wife purchased it for me for Father's Day in 2007 from her girlfriend that had it for 19 years. It is on the road again. I'm retired but it is now my daily driver.
It is the vapors that is dangerous.
Most people do not realize that liquid oil and gas have the same flash points. But gas vapors have a much lower flash point.
Lifetime MemberTemple City, CA - USA
Joined: 10/3/2010
Posts: 365
Vette(s): 1969 Daytona Yellow. 350 / Automatic.
Buy a new one at http://www.genesisautoparts.com/gas_fuel_tank-dodge-dart-1966.htm and weld away knowing there are no lingering vapors within. That is, if $250 is in the budget.
Lifetime MemberSanta Maria, CA - USA
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I have welded on a few gas tanks and I use CO2 to purge the tank. I used a wire feed welder and taped into the CO2 line that shields the wire when welding. I let the CO2 flow into the tank for a few minutes before I started welding and kept it flowing while i welded on it. Hope this helps.
in Forum: General Non-Vette Discussion
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