How to get rust out of a gas tank?

Ah, the age-old issue of rusty fuel tanks, it’s so nice you’ve returned… Okay, no one said that. Ever. It’s pretty safe to assume no one like the sight of a rusty gas tank. That’s exactly why we’ve picked up this theme as our main issue of the day!

So, let’s say you’ve noticed some rust inside your fuel tank. Is it a major cause for alarm? Or: is it nothing to worry about? Well, you’re just about to find out! We’ll talk about that, too (among other things). In the article you’re about to read, we’ll show you just how to get rust out of a gas tank!

Your best bet is to use the baking soda & vinegar combo. Detach everything from the tank and remove it from the vehicle. Pour the solution in nearly to the top and shake the tank. Let it sit until bubbles start to form and the liquid turns the color of rust. Afterward, simply rinse the tank with water. 

Think that’s not enough to quench your thirst for some rust-removal knowledge? Keep on reading!

Table of Contents

Some FAQ on the gasoline, gas tanks & rust relationship

Before we show you the step-by-step gasoline-removal guide, it’s time for something else! Let’s answer some FAQs on the awkward relationship between gas, fuel tanks & rust. A weird, yet convincing ménage à trois, don’t you think? Anyway, let’s kick-start this adventure!

Does gasoline dissolve rust?

This one’s probably downright absurd, but we’ll answer it nonetheless! Okay, so here goes nothing… Gasoline’s completely and utterly useless when it comes to dissolving rust! Here’s a more scientific explanation:

  • rust is an inorganic compound. Therefore, it can’t be dissolved or even – modified by hydrocarbons (such as gasoline). 

There are far too many better options for cleaning rust than gasoline. Many products (both commercial and homemade) do a fantastic job at it! We’ll show you some of them in the rest of the article.

Will a rusty gas tank ruin an engine?

Needless to say, engine designers didn’t make their products so you can run them with rusty tanks. Nope, that was certainly not their intention. Anyway, a rusty gas tank will surely do some damage to your vehicle’s engine! The thing is: rust will go into the fuel lines and injectors. That will, subsequently, result in your engine running lean and hot. You don’t have to be a genius to figure out that’s not good for your trusty engine!

As if the above line weren’t enough, here’s another interesting fact. The rust inside your gas tank can easily fill the filter. It can slow down or completely restrict the fuel flow.

How can you tell if your gas tank is rusted?

Of course, there are some signs you should watch out for! If you notice any of these, there’s a good chance your tank’s rusty:

  • The tank’s leaking. Do you smell gas in & around your vehicle? We’ve written about it a while ago. Check that one out!
  • Fuel economy’s reduced. Spending more & more on gas, but traveling the same distances? If so, that might be a good sign something’s wrong.
  • You’ve got some issues with the fuel pump. In other words: you’ve noticed your engine’s not running as smooth as it used to run.

Can you save a rusty fuel tank?

You’ll wanna know that that’s absolutely doable! (Sorry for the double that!) Otherwise, we wouldn’t be writing this article in the first place! Learning how to restore an old, rusty fuel tank should be one of your priorities! Many car owners will have to do this at least once in their lifetime! Unless, of course, you’re filthy rich, and you can simply buy another vehicle.

Oh, and if you’re wondering what plastic can hold out gasoline… That’s right, simply follow that link!

Now that we know that a rusty tank doesn’t mean you should replace it, let’s consider the main topic! In other words: let’s see a step-by-step guide on how to get rust out of a gas tank!

A close-up photo of a rusty gas tank.

How to get rust out of a gas tank?

Without further ado, let’s see how can one do this without any hassle! Here’s a little guide on how to deal with gas tank rust!

Safety first

Trust us, we don’t wanna keep you waiting any longer! Still, some safety precautions absolutely have to be mentioned! Here’s how you’ll conduct this process in the safest manner possible:

  • You’ll wanna work in a well-ventilated area. This one goes without saying! 
  • Avoid mixing solutions, unless the product manual demands it. Make sure you know what you’re doing. 
  • Do this far away from any heating sources or flammables. Even the tiniest spark… Well, you know that! 
  • Always have a water hose nearby. You’ll have to rinse out the tank later. 
  • Additionally, you’ll want all your fuel properly stored while you’re working. You’re never too safe with gasoline! 
  • Plug the holes present in your gas tank to avoid the ever-unwelcome spillage. Spills are always something you should watch out for! Here’s how you’ll handle them

Doing all of the above should guarantee you a safe process. Ignoring safety measures when dealing with gasoline is absolutely not recommended! Keep in mind that a single leak plus a single spark can create a catastrophe! Now let’s see those methods on how to get rust out of a gas tank!

Oh, and before you get on with it, do this first:

  • drain all the fuel that’s left from the tank. 
  • remove the fuel lines. 
  • remove the gas tank from the vehicle. 

That’s it! You’re ready to start!

Method #1 (Abrasive)

As we’ve already said, you should first empty out your tank. Afterward, add a couple of handfuls of gravel, nuts, and bolts. Add some liquid also and start shaking the tank. Liquid? You could use some good ol’ soap & water combo or white vinegar. And before you do any of this – make sure the holes are all sealed.

Anyway, depending on the size of your gas tank, you’ll either shake it manually or need to rig a mechanism. Here’s how you’ll shake the fuel tank:

  • turn the tank on all sides. Just to ensure you’ve reached every single place inside it with the abrasive material.

Once you’re done shaking, empty the tank out of the liquid and rinse it with plain ol’ water. This will help to flush out all the abrasives. Otherwise, you shouldn’t be able to start your vehicle! Don’t even try it!

Let’s see the second method we’ve prepared for today’s article!

Method #2 (Chemical)

Before you say vinegar ain’t a chemical, let’s get something straight. You can use phosphoric or muriatic acid, or acetone as the solution here. However, the safest way you’ll do it is with vinegar and baking soda! A combo we’ve mentioned quite a lot on this website.

Okay, so baking soda and vinegar, right? Right. Fill your tank with it nearly to the top. You’ll wanna let the combo sit right until bubbles start to show up. Also, the liquid should change color due to the rust particles dissolving in it. After that’s done, rinse the tank with water to guarantee it’s completely empty!

Method #3 (Diesel)

Here’s another method you can employ. It’s also not so risky just like the solution above. Anyway, you can use the abrasive + diesel fuel to clean out your tank of rust. It’s a method that’s proven to be quite effective!

Method #4 (Electrolysis)

Last but not least, you’ve got the electrolysis method! First of all, you’ll wanna get your hand on sodium-carbonate (soda ash) solution. Here’s one for the nerds: the chemical structure says Na2CO3. Your best bet is to go for the Arm & Hammer product, which you’ll find in most grocery stores.

Okay, so this method requires you to use just a couple of tablespoons of soda ash. Also, you’ll need a piece of ferrous metal (iron). You’ll wanna place it suspended inside the tank. Here’s a warning: make sure that it doesn’t touch the sides/edges of the tank. If you don’t think you can do this, it might be best to avoid this method.

Once you’ve got everything set up (the solution and the metal), it’s time to begin. Connect the positive power source and leave the whole thing like that for hours (or days, if possible).

Even though this method’s the most effective, we recommend you try out the other ones first. They’re way safer and there’s no risk of messing things up beyond repair!

Okay, so that’s about it! These were the methods you can implement to clear your gas tank out of rust!

Final words

It’s time to say goodbye, folks! Hopefully, now you’re equipped with the right knowledge! The right knowledge to handle a rust-removal process, that is! Now you know it ain’t such a big hassle (except for the last method). Anyway, we also hope you’ve enjoyed this one as much as our last article!

For more tips on gasoline and various gasoline-related fields, click right here.