Cleaning the tank with vinegar..

[sschering]

I read about a half dozen ways of cleaning a tank out here and picked the vinegar method.

Step one get the supplies..
In my case that is 4 gallons of vinegar (thanks costco) $7.50
A quart of rubbing alcohol (walmart) $2.45 funny I dn't think to check costco.
A 5 gallon bucket.. (to save the vinegar in for other rust removal projects)

This is the view into the tank when I started

The job was easy..
Remove the petcock and cap.
Drain the gas and flush out the tank with water.
Put the petcock back on.
Fill the tank with vinegar..
Cap and ignore for 24 hours..
I left it outside in the sun to cook around 3pm..

The next day around noon I took a peak.. It didn't look much different but you could scrape the grunge off with a stick and see the clean metal underneath.. I left it to cook some more.

About 8pm I drained the vinegar off into the 5 gallon bucket.. snapped on the lid and left it out by the trailer.

I pulled the petcock off and got down to business with the pressure washer..
For the first couple minutes it was gushing out brown rusty water then turned clean..

I blew out what water I could with the air nozzle then poured in 1/2 the bottle of alcohol. I Sloshed it around and dumped out another brownish mess. In went the other 1/2 bottle for a cleaner trip through..

I blew the tank out again, replaced the petcock and hosed it down inside with WD40.. The best thing I had on hand at the time..

Here's the results

 

[BassCliff]

Hi,

It does look better. But I thought the vinegar method took about a week.

Using Evapo-Rust is a bit more expensive but very easy and effective.

Before:

After:

There's more information on my website.


Thank you for your indulgence,

BassCliff

 

[979roadrunner]

Yeah, the vinegar method is for folks who have the time and patience for a week long downtime.
Also note that vinegar comes in 5 or 9 percent acidity, with the 9 percent working a bit more quickly.
Muriatic acid is quickest and most efficient, but can harm skin and will eat petcocks, so I'd say evapo rust would probably be better for quick cleaning.

 

[sschering]

I read some articles by people who did it..
Most only took 24 hours.. For $10 it was worth a try and I'm satisfied with the results.

I could have gone longer but I was worried about damage to the petcock and fuel level sending unit.

How many gallons of Evapo-rust did that take?

 

[Nessism]

Awesome work. I love those cheap home receipe type repairs.

Just me but I would have removed the petcock and fashioned a cover using a plate of metal and an old inner tube. Also, you might want to get a small mechanics mirror and flash light and have a really good look inside the tank - looking though the petcock opening works well too if you stick the flashlight in the main filler opening. It's easy to be fooled into thinking all the rust is gone if you just look down the main opening.

Thanks for sharing.

 

[Ohioan]

I've never used vinegar on gas tanks, but I have done a lot of experimenting with acids on wood and metal for finishing purposes. (building muzzle loaders).

From my experience, apple cider vinegar is the best, don't get that white stuff. It'll keep eating away at the metal long after you think you've rinsed it out. Whenever using an acid on any material it's best to neutralize it with a base. A nice wash in baking soda and water works well.

The best acid to use is nitric.... but that stuff is hard to come by... and NASTY to work with, keep some baking soda near by in case you spill some... like, on your shoe... :-\\\

Naval Jelly is another really good rust removal product. It's not as strong as nitric acid, but proper safety gear is a must.

 

[rustybronco]

The best acid to use is nitric.... but that stuff is hard to come by... and NASTY to work with, keep some baking soda near by in case you spill some... like, on your shoe...

I played around with rust bluing an old double quite some years ago. I obtained some nitric and hydrochloric acids from a well known "paint manufacturer" (which will stay unnamed). the gent asked me how many moles I needed the nitric acid to be as it is pretty thick in its strongest form. I responded, make it so I can pour it. I mixed both acids into a quart of water, placed the concoction in the emergency door opening of an old school bus, added the necessary 1 Lb of clean iron nails and ran.

I'll tell you what, It's a very scary thing to see when those acids dissolved those nails... it popped, fizzed and left a yellow/orange cloud around that bus you couldn't begin to see through and covered an area 60 feet in any direction.

nasty, nasty stuff.

 

[Ohioan]

nsty stuff indeed. That cloud will burn your lungs beyond repair!'

I imagine the bus probably rusted to pieces...

 

[979roadrunner]

That's why I recomend Muriatic, not nitric.
If it'll kill or seriously injure the user that easily, I do not consider it the best option, and muriatic neutralizes in water. I think between pressure washing and an alchohol rinse, the vinegar is probably neuatrilized.
Naval jelly would be....interesting to try to clean the inside of a gas tank with.
I still think, if you're not in a hurry, vinegar is the best choice. I'll take Apple cider vs Distilled white under advisment.

 

[Calvin Blackmore]

That's why I recomend Muriatic, not nitric.
If it'll kill or seriously injure the user that easily, I do not consider it the best option, and muriatic neutralizes in water. I think between pressure washing and an alchohol rinse, the vinegar is probably neuatrilized.
Naval jelly would be....interesting to try to clean the inside of a gas tank with.
I still think, if you're not in a hurry, vinegar is the best choice. I'll take Apple cider vs Distilled white under advisment.

Why not try Balsamic as well

 

[Qdude]

I have had success with two rusty tanks and am currently doing a third. I have a pack of BB's (about 400) that I put in the tank (petcock removed, duct tape over aperture) and put in the clothes dryer. (wedged with cushions so that it does not flop around at all, it just rotates with the dryer basket) I run it for about 4 hours rotating the tank every once in a while. Then I rinse it with water. Yes water, copious amounts of water. There will be a lot of residue in the tank that needs to be flushed out. Then the vinegar rinse to deal with any flash rusting. The BB's knock the walls well and clear them of any flake-rust (and fuel residue as well)

 

[sschering]

I have had success with two rusty tanks and am currently doing a third. I have a pack of BB's (about 400) that I put in the tank (petcock removed, duct tape over aperture) and put in the clothes dryer. (wedged with cushions so that it does not flop around at all, it just rotates with the dryer basket) I run it for about 4 hours rotating the tank every once in a while. Then I rinse it with water. Yes water, copious amounts of water. There will be a lot of residue in the tank that needs to be flushed out. Then the vinegar rinse to deal with any flash rusting. The BB's knock the walls well and clear them of any flake-rust (and fuel residue as well)

I can see how that would be really effective and also deadly..

Wife:
What's that noise?

Me:
Ohh I put my gas tank in the dryer with those extra blankets from the closet.. (instant death)


I did manage to get a good look inside down to the floor of the tank with a flashlight.. It's about the same all over in there. I couldn't get a good picture of it.

 

[Billyboy]

WOAH! Hang on there Gonzo...
IF you spill acid, neutralization should be the LAST step. Absorb, dispose, flush, THEN neutralize. Most people don't realize that adding a base to an acid or vice versa foams and splatters boiling corrosive material all over the place! Strong exothermic reactions occur.

IF YOU GET A CORROSIVE LIQUID ON YOUR SKIN, GET IT OFF, DO NOT NEUTRALIZE!!!
Flush with water until you KNOW you got it all. 15 minutes minimum.

Source: 12 years in a chemical plant.

However, very small amounts are usually ok. Like battery posts, I use a soda ash solution, then flush with the hose.

 

[Kerry]

Why not try Balsamic as well

You can make a nice vinaigrette with what you drain out of the tank. Just add a little crushed garlic, oregano and basil and some extra virgin olive oil...

 

[Guest]

Interesting thread..
I wonder if the vinegar will remove any previous partially peeled liner?
Got plenty of time...

Im thinkin aquarium rocks for this task.

 

[979roadrunner]

Use screws or some such, that way a magnet can assist getting them out

 

[Nessism]

Use screws or some such, that way a magnet can assist getting them out

In my experience nuts/bolts/screws are too coarse and don't get into the nooks and crannies, and BB's are too smooth to scrub the metal. Aquarium rocks do a great job of scrubbing the metal, but they take some time to remove. You can also use pea gravel, but like the BB's it tends to be too smooth.

Regarding all the techniques discussed here, please understand that unless 100% of the rust is removed, it will come back. Look at the pits in the metal and if you see any orange, keep going with the derusting process. My preference is to seal the tank after derusting to assure the rust doesn't come back. I usually use phosphoric acid to derust since it eats the rust and converts what's left into iron phosphate. Oxalic acid works well too and doesn't eat into the base metal like some other acids. HCl is bad from what I've been told since the Cl atoms bond into the metal and won't stop corroding the metal, even if rinsed. The devil's in the details.

 

[tkent02]

I tried vinegar on a rusty old hammer, twelve hours worked.
It was about as rusty as a medium bad tank.
I still prefer electrolysis, but might try vinegar on one just for kicks.