Best way to clean and prep gas tank for welding?

[CDMBill]

Guys, I have a bought new, seven year old stock type gas tank that I need to update in terms of some internal baffling and bungs for return lines in new places. The sump I added when the car had a carb on it no longer works well with EFI.

What is the best way to clean the tank so that I can open it up to add a couple baffles and weld in some bungs?

What techniques are best for the cutting and welding processes themselves.

Yes I know welding on gas tanks is dangerous.

My thinking is that I can effectively clean and nuetralize the remaining vapors and residue. I will open it up with a cut off wheel which will bviously throw sparks. I could use a Sawzall as an alternative, it'll still throw sparks. Once open I can rreally scrub the inside, however its pretty clean now.

[CDMBill]

This is how it looks now just out from under the car. I powdercoated it when I installed it in '05.

[squirrel]

The best way is to buy a new one...you should be able to sell this one to someone who's running a carb, right?

They only cost $130....

[CDMBill]

That may well be the right answer, but I'd still like to know the options to re work this one.

[BBR]

I just pressure washed mine with soap & water when I did the sump. Let it air dry for a week or so and went after it. No probs at all.

[DanStokes]

Two possible methods:
1) Buy a new tank and start there.
2) Take the tank to a good radiator shop and explain in detail what you want. Drawings are helpful.

But I'm allergic to exploding gas tanks. I saw an instructor at Ferris State College ride one across the street - not good.

Dan

[SuperBuickGuy]

Choose one or more options
all of these options presume you have drained and dried the tank before you start

1) displace the oxygen in the tank with Argon (fill from the top, argon is heavier than air and will displace the air). How do you know when it's full? you eduguess
2) fill the tank with water before you cut - then there just isn't the space for a large fire

once it's opened enough to put baffles in, the danger is pretty much gone

[STINEY]

Soap and water works for me too.

Or you could use my alternative approach...........take the tank you intend to weld on, store it until you actually have the time to do the work on it, and by that time years will have passed, rendering the old fumes nonexistant and the tank harmless, even without soap and water.

[SuperBuickGuy]

Soap and water works for me too.

Or you could use my alternative approach...........take the tank you intend to weld on, store it until you actually have the time to do the work on it, and by that time years will have passed, rendering the old fumes nonexistant and the tank harmless, even without soap and water.

I sit corrected, that way works pretty good too

[Barry Donovan]

The best way is to buy a new one...you should be able to sell this one to someone who's running a carb, right?

They only cost $130....

injection tanks are supposed to have a higher pressure rating, and a return line...and get quite a price hike.

I ondered why atomic EFI used no return lies, that was a reason..the tank needs more than a bung to play those games.

I don't bring up my subaru often, but that is one with both generations of fuel..the injection is 450 buck, the carb is less than 100.

there is a means to add a surge off to the side someplace..that way any grade tank that was made for your car can be used.

I'd rather weld like the op. try filling with water..?

[Mr4Speed]

Run a hose from the tailpipe of a running car to the filler neck of the tank you're working on while you cut and weld. No oxygen-no boom.

[redragtop]

You could always use a nibbler or power shear. We use them to cut up rotted fuel tanks so the scrap yard will take them. Rewelding the tank closed is a little different, but you are able to clean it good while it is open

[CDMBill]

I just pressure washed mine with soap & water when I did the sump. Let it air dry for a week or so and went after it. No probs at all.

My intuition is that this is right. It has three pretty large openings for the factory filler and the outlet/sender and the vent fitting plus the sump and three bungs I added originally.

I'm going to clean it with non-flamable solvent first then simple green and water and then do sniff test,a dn then go from there. i want it done this weekend and I couldn't find a new one locally.

[nesabo]

My intuition is that this is right. It has three pretty large openings for the factory filler and the outlet/sender and the vent fitting plus the sump and three bungs I added originally.

I'm going to clean it with non-flamable solvent first then simple green and water and then do sniff test,a dn then go from there. i want it done this weekend and I couldn't find a new one locally.

Please report back asap so we know all is ok...

[yellomalibu]

The guy who welded a sump into my original tank just stuck a water hose in the tank and let it run for a while to flush it thoroughly... but don't worry, no residual gas contaminated the ground, it ran right into a lake.

...and a year or two later, there was so much rust clogging my filter, I had to ditch the gas tank and buy a fuel cell.

So, I vote buy a new tank. Don't flush with water.