How to clean a gas tank out!!

[70 Bowtie]

Hey all,

I finally got the small block 400 and th350 in my truck, I now need to get all the crap out of my gas tank! What is the best way to clean out a tank?

Thanks in advance!

Brett

[Tx Firefighter]

I start with chain and water. Then muriatic aicd diluted with water. Finish up with POR15 gas tank sealer. You can save pretty much any tank that way.

Shouldn't be over 20 bucks total either.

[BrianJordan]

Originally Posted by Tx Firefighter

I start with chain and water. Then muriatic aicd diluted with water. Finish up with POR15 gas tank sealer. You can save pretty much any tank that way.

Shouldn't be over 20 bucks total either.

[BrianJordan]

Originally Posted by rick980

What if you just want to drain it and rinse it out? I have a new tank with god know how old the gas is.

pull your tank out ,after u drain it then carb dip to rince it out. then rince with water and let it air out 4 a day or 2.

[FUNMUDDER]

If its rusty on the inside, screw it an get a new one. I did that. My old tank looked like a million dollars on the outside. Inside was a different story. I don't know about sealing or lining them. People say it works great or not at all.

[Tx Firefighter]

I believe you'd all be happy with the method I described. Rust is no object to the chain and muriatic acid.

I used to mess with some cars where replacing the tank was not an option, like ancient VW Bugs, and I wound up fixing some mighty bad ones. The POR15 sealer will even fix small rustout pin holes.

[Longhorn Man]

At work we have an in house radiator shop. We also clean and repair fuel tanks on a daily basis. Mostly diesels, and mostly big 50 gallon tanks, but it's all the same really.
We use steam. Start with the tank drained, and the sender removed, reach in with the steam cleaner wand and start blasting on the nasty rust. After the bulk of the rust and scale is removed, then we just tie a rag on the trigger of the wand, and leave the wand in the tank and walk away for an hr or so. Come back, drain it, inspect it, then repeat if needed.
once it is clean and dry, (the hot water evaporates in a matter of min... instead of days) then a pour in liner of some sort is needed. POR has a fine product, and there are a few more out there too. What ever you do, you need to follow the directions to the letter. Inside the tank is the LAST place you want coatings pealing.
Before doing the liner, you'll want to check the tank for leaks. Pin holes can be ignored. However, where the filler neck meets the tank, that commonly cracks from lazy people leaning on the gas pump nozzle when filling up. You'll want to have that soldered or brazed. If the gas fumes are gone, it is safe to work on, but if it still stinks of gas, then NO FLAMES.
That's how we do it every day.

[70 Bowtie]

Thanks for all the replies,

TX Firefighter, What do you mean by chain and water?

Longhorn Man, I talked to a radiator repair shop here in Huron, and he said his tank could not hold anything longer than 4'. My tank is 4'11".

Thanks again for your help!

Brett

[Tx Firefighter]

You put a piece of chain in the tank and shake the tank bak and forth every which direction. The chain knocks off the big pieces of scale and rust.

[farside847]

I would strongly recomend NOT USING A LINER. They all break down in acetone and acetone is now being added to gas at the pump. I had my tank cleaned and sealed by a radiator shop and it was being eaten up and forced me to have my carb rebuilt twice before we figured it out and replaced the tank.

If your tank is nasty, replace it. There are tons of good tanks out there, or get a new one.

[70 Bowtie]

Farside847, due they put acetone in ethanol? I plan to put a new tank in, right now $ is short, and I need to get my truck on the road (daily driver for now). I see your from the Bay area. I grew up in Fremont, then Hayward!!.

Thanks for the input,

Brett

[67chevemall]

no liners
buy a fuel cell.
vaccum is all you need.

[Longhorn Man]

Originally Posted by 70 Bowtie

Longhorn Man, I talked to a radiator repair shop here in Huron, and he said his tank could not hold anything longer than 4'. My tank is 4'11"...

I'd go to another rad shop, he wants to dip it in chemicals. This is not really a good idea on an old tank. This basicly removes a layer of metal....simplified statement... but basicly acurate.

[xam]

Acid will not remove the old fuel varnish, you need strong detergent and (preferably) hot water. If your tank has "pin holes" the coating will seal these AND THE IT WILL FAIL. The pin holes allow access to the substrate (tank) behind the coating. Not all coatings are hurt by acetone. I coat all my tanks cars/trucks/motorcycles I am to lazy to re do my carbs let alone the fuel tank.