Technical How to clean inside of gas tank?

Please describe, in great detail, the exact procedure(s) involved in completely cleaning the inside of a fuel tank of fuel/fuel vapors etc. in order to do cutting and/or welding so i don't blow myself to the moon. (Not trying to be funny.)

 

Soap and water and a couple handfuls of 1/4 inch nuts and shake well

 

Take it to a radiator shop, and have them do the welding.

Or buy a new tank, and you won't have any vapors to deal with.

Seriously.

 

Also....dont know how old the tank is ...but many tanks are galvanized. Welding galvanized steel if not properly done is a dangerous deal...im with Squirrel...have someone else do it..

 

How long has the tank been sitting? Mine has been sitting since 1978, have a couple pin holes on the top where it was exposed to weather. I am going to use my grinder with cut off wheel to open it up, see if I want to clean it out and weld a new top on.

I would think that you could have the tank dipped and flushed at a radiator shop, may as well have them weld it while is there. As squirrel suggested.
I wonder if I bought some radiator flush and cleaned a tank at home, if it would then be safe to weld on?

 

Fuel tanks are far cheaper than the results of medium-sized explosions.

 

I would also look at replacing the tank

 

I know of no safe way to do this. I would run over it with a dozer, send it to scrap, and get another tank. I have welded on them before, but never again. 55 gallon drums are another source of unwanted explosions. I do not care if they have been laying around fo forty years, or forty decades.

 

I have welded many fuel tanks, it is really no problem. Just run water in it until you can't smell gas and start welding. as far as the rust goes, I have done the nuts and bolts thing, just shaking them around until it knocks the rust off and flush it out, but the best way is to use muriatic acid, just don't leave it in too long and rinse it out with water. after the water put some oil in so it won't rust again.

 

If you still want to do it yourself.....introduce a few feet of a small chain and shake well.....

 

Most tanks I've seen are at or below $200.00. By the time you invest 10 hours of labor, the money for chemicals to clean and seal, time to weld and the inherent dangers, not to mention it's a system on your car that needs to be clean and reliable EVERY time, go buy a new tank and be done with it.

My $0.02 worth.

 

When I bought my 50 the previous owner told me when he would go out on a long drive it would stumble and stall and not start again
Tow it home let it sit and it would be fine
He said it's something electrical shorting out !! Lol ok it's a 216 with points not all that technical


Drove it the first day made it around the corner and it stalled would not restart

No fuel to the carb had an inline filter that was full of " snow flakes " and so was the fuel pump

Dropped the tank and the bottom was covered in body shop dust Rust and bono filings

Didn't trust cleaning it out


Bought a repop 69 mustang tank and dropped it into my trunk floor


Tank and sender where under 200 bucks

If your tank or a comparable tank are available why mess around ?


I did send the tank on my 53 Chrysler to get cleaned and dipped as the car sat for a long time
Cost me under $100 bucks at a place called gas tank and radiator re-nu

 

Compared to the rest of the parts we buy for our old cars gas tanks are cheap.

Sent from my SAMSUNG-SM-G890A using The H.A.M.B. mobile app

 

Ive welded fuel tanks. you run exhaust into them when you are welding. The exhaust consumes and dilutes the oxygen in the tank and it will not explode. Now if its very rusty your better off with a known good clean tank. Don't touch a empty tank without shielding gas with a die grinder. The sparks are just the same as a cutting torch. And exploding gas tanks can kill. years ago there was a collection of scrap vehicles that where to be sold in one lot at Neelyville Mo. I bid on them but the guy who bought them apparently had more money than me. and he was using a cutting torch to remove the rearends. and apparently hit a gas line. and the gas tank blew up and killed him. Unless you have the proper Know How and Skill you shouldn't attempt to repair fuel tanks.

 

We have a 48 dodge Pk when you filled it full the gas tank leaked. The dust and dirt over the years had rusted a few pinholes into the top of the tank. My eldest son sanded the area around the holes by hand until it was bright and shiny with 36 grit sandpaper. Then using a blunt punch he dimpled the holes. Then he filled them with JB weld and repair is still holding up.

 

Put a magnet attached to a wire into a rusty gas tank. And the magnet will collect the rust. And you can pull it out and clean it from time to time.

 

If you've way more time than money ... I've read all the techniques. Collection of rocks... or bolts & nuts.. Shaken, not stirred.

Short lengths of chain sounds pretty ingenious, easier to remove maybe. One guy on another forum or maybe it was here, attached the tank to a cement mixer, and left the automatic rotation to do its part.

After reading about all the solvents (disposal of a mess) and BS involved I spent $224 for a brandy new tank delivered to my door. How much is your time worth?? If the tank is otherwise sound having it boiled out by a radiator shop sounds like the way to go. A clean, rust free tank solves a lot more problems than one might think, all that sludge and varnish and sediment remaining gets dissolved by ethanol fuels and plugs or restricts lines, filters or gums up carburetors. Hafta have a clean tank, the only question is how much hassle to get that way.

 

I don't fuck around with tanks at all. The one for my Ford was $157 at Rock Auto and $10 to ship.

 

Good thread, I appreciate all the advice given here. I will certainly be more cautious working on my tank. Fill it with water "IF" I cut it open. I have another parts truck the tank might be in better shape.
And I have a couple tanks from newer trucks set aside just in case cant fix mine.

The 48-52 pilothouse trucks do not have a aftermarket tank available, At least I have not found one.
They do have tanks for the 46-47. They bolt to the frame fine, but need modification on the filler neck.
That modification is inside the cab behind the seat, so needs to be done right for fumes.
That tank cost $350 + the ride and then the mod.
Just saying, it might be worth putting a couple hundred in fixing what I have.
I do want to keep original fuel gauge/sending unit also.

 

I would skip the coating too....it seems to cause problems, more times than it helps.

 

I agree, I have heard both good and bad about coatings. It seems if you do proper prep and follow directions exactly, it can work really well.
But if something goes awry, you end up with a mess that probably needs to be tossed in the scrap pile.

 

Well before I got. Anew tank for my 42 Fargo I took my old one and used a nibbles to cut th stop off just above the seam. Did the same with a junky spare and then had a rad shop solder the two good halfs together. Worked well for 15 years. You might try his with yours.

 

Having had to cut out the hole to weld a dropped pickup in many gas tanks. Plus fixing rusty ones. I use my pressure washer first with soap to get the crud out. Then run a water hose into the tank and let it run. When I don't smell gas. I leave it full and run a hose from a running car and do my repairs.
Been using that method for 30 years. Now days I just buy a new tank if available.
I did a 65 GTO once that had rusted the top of the tank. I used a cup brush on m grinder and cleaned the top of the tank and used fiberglass mat and resin to cover the whole top of the tank. It lasted for years. I figured they make fiberglass motor cycle tanks. Why not ?

 

I had one on My Olds station wagon .Talk about a hard tank to find. Took it to a shop and they cleaned it and repaired the leak .It was under $100. and well worth it. Bruce.

 

? Dont understand what you mean here.

 

I can only speak for myself. But I would either buy a new tank,{ if available } or have one built. I've learned not to use an old fuel tank. It will be money well spent. And they're Hot Rods, so they don't have to be original. Just reliable and safe. {My 2 cents} or pay a shop, like Bruce said, and be safe.

 

The exhaust in the tank works if you get a really good scald. A slight error can cause a sometimes massive explosion. A neighbor of mine tried it on a larger tank. His wife and daughter miss him greatly. NOT LOL.
Pete

 

Fiberglass does work really well. Just don't clean the tank with a grinder.

 

Our pilot house dodge has a 59 engine. and they also used the 59 flywheel and starter. Now its a push button instead of a stomp pedal. And the starter drive went bad. couldn't find one new or used anyplace. finally someone told us that massey ferguison used the same starter drive. Shure enough went to the Massy tractor dealer and they had brand new ones in stock. And like you I would attempt to fix my tank rather than pay big money for a tank that might not work. I stripped out a washing machine and wired it to where it only agitates. I place the gas tank on a attached rack. pour in a gallon of paint thinner and a couple handfuls of shattered tempered glass. and let it agitate and stop and reposition from time to time. I mostly use that method to clean tractor gas tanks.