Rusty tank to rust free tank using vinegar

[RealSaltBlake]

I recently acquired a new tank for my 1971 Kawasaki G3SSA and the whole inside had surface rust. So I went with the vinegar route (cheaper) to get it clean and it worked brilliantly!

The steps are as follows:

1. Remove the petcock and secure the bottom with tape. Make sure it is done enough to hold liquid.

2. Put nails or screws in a dry tank and shake it around to break up the loose rust. After shaking it on and off for a while pour out the loose dust and the nails/screws.

3. Pour in white vinegar to the brim, tighten the cap, and let it sit for 48 hours.

4. Remove all but about a gallon of vinegar and put the nails/screws in and shake it around for a few minutes.

5. Pour out the vinegar and nails/screws.

6. Rinse out the tank with a hose and swish around the water.

7. Pour out the water.

8. Immediately after pouring out the water, pour in about 40 oz of Coca Cola and swish it around.

9. Pour out the Coca Cola.

10. Rinse out the Coca Cola by adding in about a half gallon of gas and about 250mL of two stroke motor oil and mixing it around to make sure you coat the whole tank.

11. Pour out the gas and two stroke oil mix.

12. Pour in mineral spirits (denatured alcohol) and shake it around.

13. Pour out mineral spirits.

I will also add that you want to be fairly quick when pouring out and pouring in the different liquids. I did not get any flash rust using this method. We also had 100% humidity and I still didn't get any flash rust.

Hope this helps anyone looking to cheaply clean the inside of a tank.

Here is the result:

(About a half gallon of gas is inside)

 

[jetmechmarty]

The one caveat I noted in your method was that you chased the acetic acid with phosphoric acid (vinegar with Coca-Cola.) If you were attempting to neutralize the acid at this point, a baking soda solution would have been a good choice. I'm sure you got rid of it with your gasoline solution, so no foul.

Do you plan to leave the tank bare metal, or are you installing a liner? Either way, I'm interested in knowing how it works out. I'm in the process of removing a failed liner myself. I will probably derust with a method similar to yours.

 

[socalmike_cb72]

Thanks for the post Blake. I've been hoping to so this, but didn't feel too confident that the results would be that great. Feel a lot better now, after reading this.

Wondering about liner. Necessary to line the insides of the tank or just leave as is and acid wash again when needed?

 

[Mr.E]

Cool post man. I recently did a similar job using CLR (bathroom cleaner) which I think has similar properties to vinegar? I dunno. But as for the tank liner, I personally hate using them unless absolutely necessary. Therefore I just go bare metal and clean as needed. My daily rider has been clean for 2 years and is just now to the point where I *may* clean it this winter.

 

[JRK5892]

very cool!

 

[RealSaltBlake]

I used two stroke oil as a temporary coating. I am using the tank right now on the bike, however.

 

[socalmike_cb72]

Is the two stroke oil just a temperary coating until you place the gas? Or does the oil somehow stick to the insides and help prevent future rust?

Either way, gona do this later when I get home today. Already have 4 gallons of vinegar and bottles of cola.

 

[jetmechmarty]

If you have a tank that isn't too terrible, you can use this:

It won't etch the tank. It will remove the rust and that is all. The acid bath will etch the metal and give your tank liner of choice a good surface to cling to.

I'm not sure what I want to do. I'm in the midst of removing a failed tank liner now. Ethanol fuels will promote rust if left in the tank too long. I'm a glass half empty sort of guy, but it looks like a lose/lose. I am encouraged to know someone is having success with an unlined tank.

 

[koolio]

Yea vinegar and coca cola quite known rust removal methods but they take time.

Have you ever thought about reverse electrolysis for rust removal, quicker and safe.

You can then do zinc plating of the inside of the tank, see here for exact details:

http://www.triumphrat.net/classic-vintage-and-veteran/160243-zinc-plating-at-home.html

 

[jetmechmarty]

I'm not sure how one would zinc plate the inside of a tank. What was done in that other forum was plating hardware. I did not study the thread carefully, but it appears zinc plating the inside of a fuel tank might not be practical. If someone has done that very thing, I would love to know how it was done.

I have done rust removal via electrolysis. It requires some patience, but it is not difficult. Metal Rescue works great, but it isn't cheap. If I have a badly rusted tank that I expect to be putting a liner in, the acid bath is cheap and easy. I simply picked up a gallon of phosphoric acid from the hardware store. It doesn't take much acid mixed with water to get the job done.

 

[vw121]

I got the Eastwood kit. I'll let you guys know how that works

 

[djelliott]

I've had amazing luck with a product called "Milkstone Remover". You can get it at Tracter Supply Co. 8:1 mix with water and about 24hrs and the tank is amazingly clean.

 

[bowman41]

I've also got a tank with some light rust inside. I'll have to keep an eye on this thread. I'm interested in low cost and minimal maintenance once the rust is removed. I'm thinking this might be the way to go.

 

[jetmechmarty]

I've had amazing luck with a product called "Milkstone Remover". You can get it at Tracter Supply Co. 8:1 mix with water and about 24hrs and the tank is amazingly clean.

This is also an acid treatment. It works.

 

[koolio]

I'm not sure how one would zinc plate the inside of a tank. What was done in that other forum was plating hardware. I did not study the thread carefully, but it appears zinc plating the inside of a fuel tank might not be practical. If someone has done that very thing, I would love to know how it was done.

I have done rust removal via electrolysis. It requires some patience, but it is not difficult. Metal Rescue works great, but it isn't cheap. If I have a badly rusted tank that I expect to be putting a liner in, the acid bath is cheap and easy. I simply picked up a gallon of phosphoric acid from the hardware store. It doesn't take much acid mixed with water to get the job done.

I often get lazy and simply do vinegar, coke or another method for rust removal.

For plating you need flexible zinc roofing strips circa 99-99.5% (99.9% i.e zinc anode rods are too brittle), long strips of it usually a small titanium content, this is shaped through the fuel cap so that the strips are in line of sight contact with most parts of the tank or you can plate one side of a tank at a time by plating with the tank on its side. The whole tank acts as the cathode and is wired so, the zinc strips act as the anode.

I don't have too much time to go into details but will show you some pics hopefully next week.

 

[socalmike_cb72]

Just finished de-rusting the inside with vinegar and I'm really happy with the results. Its not perfect, but definately an improvement. Soaked it for a couple days which was fine. Had the coke, but felt like it didn't need another bath. I did use it to rinse it out after.

 

[mohabie]

Im gonna try this method on a gs850 tank that needs some tlc. Thanks for the tip.