How to Keep Gas Tank from Rusting After Cleaning

Every vehicle or motorcycle that runs on fuel has a gas tank in which the fuel is stored. Over time, with use, it is possible that moisture (rainwater) gets inside the tank. Water in a gas tank isn’t something you want to deal with as it can cause rust underneath the tank.

However, it is possible to prevent a gas tank from rusting i.e. you can take preventive measures rather than corrective measures when the damage is done. You can as well clean a gas tank but how do you keep a gas tank from rusting after cleaning?

You can keep a gas tank from rusting after cleaning by using tank sealer, abrasive chemicals, and electrolysis amongst others.

Can You Clean a Rusty Gas Tank?

Yes, you can clean a rusty gas tank. When the gas tank in a car or motorcycle gets rusted, it is possible to have it cleaned instead of looking for a replacement. A replacement may not be the best option especially if you are trying to cut costs.

How to Keep Gas Tank from Rusting After Cleaning

You can keep a gas tank from rusting after cleaning through:

The Use of Tank Sealer

One of the many ways to prevent a tank from rusting after cleaning is by using a tank sealer. Tank sealer stops rust, fuel leaks, and corrosion.

To use a tank sealer, the content should be poured inside the tank and slosh around after which you can leave it to sit for about 5 mins on the surface, then slosh around again.

The length of time it will take the sealer to dry up will depend on the thickness of the coating. Coating the tank with tank sealer is a good way to keep it from rusting after cleaning.

The Use of Abrasive Chemicals

Another way to keep the gas tank from rusting after cleaning is by using abrasive chemicals. The downside to using abrasive chemicals is that some may react with the fuel, therefore, if you are going with this option, you have to get abrasive chemicals that won’t react with the fuel afterward.

The Use of Electrolysis

You can also use electrolysis to keep a gas tank from rusting. Electrolysis is an absorbent that helps in absorbing water that can lead to rust in the tank. It absorbs water and ensures the tank is dry thereby preventing rust.

You can watch the video below made by Autorestomod Manic Mechanic Gasoline Media YouTube channel where he explained how to slow down rust on your gas tank.

What to Put in a Gas Tank to Keep it from Rusting?

To keep a gas tank from rusting, you can do or put the following:

1. Put a Valve and Bung in Place

By putting a valve and bung in a gas tank, you can be sure of keeping it from rusting for much longer.

Installing a valve is a good way to extract water that may have found its way inside through the bund. The only time the valve should be opened is when you want to remove water from the tank.

Installing a bung will help to detect the liquid interface between oil and water, ensuring that it is fitted ¼ inch from the tank bottom.

2. Coat with Paint

You can also coat the gas tank with a rust-resistant finish. Doing this will help to repel water and prevent rust from forming underneath the tank.

3. Keep the Tank Topped Up

To keep a gas tank from rusting, ensure the fuel is continuously topped up. Leaving the tank half-filled or low on fuel is an easy way for air to get in. When the air gets inside the tank, it causes humidity and condensation which in turn leads to rust.

4. Fuel Polishing

The level of contamination present in the fuel will help determine if fuel polishing should be done. However, fuel polishing can only be done if the fuel is not badly degraded.

To polish the fuel, two processes are involved; filtration and depolymerization. This process helps to break down particles in the fuel and polish it.

What Can you Put in a Gas Tank After Cleaning It?

If the gas tank wasn’t cleaned with water, you will need to use water to flush out residues and remaining dirt in the gas tank and of course, a hose should be in place to remove the water from the tank. After which you can put compressed air to dry out the moisture in the tank.

Although compressed air is a good way to dry up moisture, it can’t be completely trusted to do a thorough job therefore, you will need to use anti-freeze afterward to completely dry out excess moisture in the gas tank.

How to Dry Out a Gas Tank After Cleaning It with Water?

After a gas tank must have been cleaned with water, it is important that you dry it before putting fuel inside. To dry the tank, you can do the following

  • Use Compressed Air: To dry a gas tank after cleaning it with water, you will need compressed air. Compressed air is said to be air under pressure that is greater than air in the atmosphere. It is a form of stored energy.
  • Inspect the Tank for Rust: After cleaning and drying the gas tank, it is important that you inspect it for rust or damages especially if the vehicle or motorcycle has been in use for some time. If you notice any sign of rust or physical damage in the tank, you must either repair or replace the tank depending on the severity of the damage. A damaged gas tank, irrespective of how small the damage may seem, shouldn’t be overlooked.
  • Add Anti-Freeze: Using compressed air may not be enough to dry out a gas tank therefore, you may need to add anti-freeze to absorb any remaining moisture in the tank.
  • Let the Tank Sit for Some Minutes: After you must have added anti-freeze in the tank, allow it to sit for at least 30 mins before filling it with fuel.


It is always better to take preventive measures and prevent the tank from rusting than waiting till the damage is done to spend a lot on repairs and probably replacement.