If you want to fix an old car or do maintenance on a motorcycle or lawn mower, at some point you will need to clean your gas tank. This task may seem overwhelming to the novice, but with a minimum of knowledge and effort, you can do it much more easily. Ultimately, you will have a tank free of debris and contaminants that could have damaged your engine.
Steps
Method 1 of 3: Clean a motorcycle or small engine tank

Step 1. Disconnect the tank
Before doing anything, you should take the trouble to disconnect the tank from the motorcycle or any other machine. If you don't, you won't be able to access or clean the room safely. It is therefore important that you can disconnect the tank and unscrew the screws or bolts that hold it in place.
- Be aware that you need to remove the spark plug and fuel line when dealing with lawn mowers or similar attachments.
- For motorcycles, remove the fuel cap, the drain valve and any hoses that may be attached to it.

Step 2. Seal the fuel line
You will need to seal the fuel line after detaching it. If you don't, not only will residual gasoline come out of the line, but dust and other objects could end up in it, which can cause engine problems.
- Take a smooth-sided clamp and attach it to the fuel line near the carburetor.
- Separate the carburetor and fuel line.
- Put the fuel line over a bucket and remove the clamp.
- Allow the contents of the line to drain into the bucket.

Step 3. Empty the reservoir
Pour the remaining fuel into a suitable container which does not present any danger for the conservation of such a product. If you are unable to collect everything, you can use a suction hose or similar instrument to be able to empty the tank.
- Let the tank dry completely.
- Keep in mind that you will not be able to clean the tank properly if you do not drain the remaining fuel. In addition, you need to make sure that there is no fuel left in the tank.

Step 4. Examine the tank
It is important that you can take the time to carefully examine the tank for any issues that could compromise its integrity. For example, rust, defects or the like can pose potential accident hazards or damage the engine.
- Put the tank outside in daylight so you can see inside. In case you need more light, all you need to do is simply turn on a flashlight and point it at the tank.
- You should pay special attention to wear, defects in the material of the tank or rust spots.
- Take the trouble to examine the fuel filter to make sure it is clean. If not, then it should be replaced.

Step 5. Spray high pressure water into the tank
You will be successful in removing any deposits or build-up on the bottom of the tank using high pressure water. At the same time, you should avoid getting chemicals, such as soap, into the tank, which could cause engine problems.
- Set the vaporizer and hose to high pressure.
- You may need to lower and aim the spray at different places in the tank.
- Consider using a pressure washer if you find that there is a significant buildup of rust inside the tank.
Method 2 of 3: Clean a motor vehicle gas tank

Step 1. Jack up the vehicle
Before removing the tank, you need to jack up the car. To do this, put a jack under the vehicle and gradually raise it. This will allow you to have space to be able to work under the car.
- Consider using two jacks to lift your car safely.
- It is advisable to put the jack (s) below the lifting points of the car. Consult your user manual for these locations.

Step 2. Remove the gas tank from the car
Before cleaning the tank, you should make sure to remove it from the car. This will allow you to empty it, examine it and clean it up as it should. Also keep in mind that you need to loosen the straps and bolts that hold the tank in place in order to remove it from the car.
- Make sure you do not stand directly under the tank when disconnecting it.
- You will need to use another jack, ideally a transmission jack, to lower the fuel tank.

Step 3. Empty the reservoir
After removing the tank, you must then completely empty it of any fuel that may still remain in it. The extent of this process may depend on the condition and type of the tank, or the amount of fuel left in it. To empty your vehicle's tank there are a number of things you can do.
- Use a suction device to be able to transfer the fuel to a storage container.
- In case there is still fuel that you still cannot remove, then you should turn the tank upside down and let it drip into a container. You may find that mud or other debris will come out along with the rest of the gasoline.

Step 4. Degrease the reservoir
You may need to degrease your fuel tank if you notice that there is still the smell of gasoline coming out after emptying it. Be aware that you will get better results by degreasing the tank.
- You can use a degreaser like Marine Clean.
- Make an effort to mix hot water with dish soap.
- Leave the soap and water solution or degreaser in the tank for up to 24 hours.
- If the soap solution or the degreaser does not give the desired result after the 24 hour period, then consider degreasing your vehicle's tank again for a longer period.

Step 5. Clean the pressure tank
You will need to take a pressure washer and spray the inside of the tank after removing it from the car. This action will allow you to remove debris, dirt and small flakes of rust and rinse the fuel deposit.
- It is recommended that you use a regular garden hose and a spray bottle or pressure washer to clean the inside of the tank.
- You may need to orient the sprayer at different angles to be able to remove any light rust and other build-up of deposits that may be inside the tank.

Step 6. Use a cleaning solution
If there is a significant amount of rust or dirt inside the tank, be aware that you will need to use commercial solutions to remove it. These solutions work by chemically breaking down rust. This will allow you to easily rinse and remove the debris that is inside your tank after using them.
- Choose quality acid solutions that will dissolve rust in a tank.
- Keep in mind that cleaning solutions should only be applied to tanks that have not been used for a long time.

Step 7. Rinse the tank
After using the cleaning solution or even a degreaser (like a mild soap), you should rinse the tank several times so that the soap or foam residue is completely removed. Be aware that you risk damaging your vehicle's engine if you do not remove all chemical residue from the tank.
- Remember that you must empty the tank and refill it to be able to remove the other debris that remained there after removing the accumulations of rust and deposit.
- Take the trouble to rinse the tank until there are no more foams or bubbles in the water. You may be required to do this 2-3 times.
Method 3 of 3: adopt security measures

Step 1. Let the tank dry
You must let the tank dry before putting it in its location on the car. Once you have cleaned the inside of the tank, you must let it dry completely. If this principle is not followed, there is a good chance that the water will mix with the new gasoline that you are going to pour into the tank, which could damage the fuel system or the engine of your vehicle.
- Turn the tank upside down if necessary to drain it properly.
- Leave it outside overnight.
- You must make sure that the tank is not placed in a humid place.

Step 2. Dispose of gasoline appropriately
After emptying a tank, you need to make sure that you dispose of the gasoline properly. If you don't, the fuel could contaminate the water table in your community.
- You must keep gasoline in approved containers.
- Contact your local waste disposal service to find out exactly where you can pour gasoline without any problem.
- Be aware that you can pour old gasoline that was in your car's tank at a toxic waste disposal site near your home.

Step 3. Call a mechanic if you have any concerns
It's best to bring in a professional mechanic if you're having trouble cleaning your vehicle's tank, or if you have a problem that you can't fix. He has certainly had to clean gas tanks before and as such he will be able to give you useful advice.
Just contact a mechanic if you are unsure how to safely lift and remove a vehicle's tank. He will be able to do this without any problem

Step 4. Wear proper protective gear
You should always wear proper protective equipment when handling cleaning solvents or gasoline. Without these tools, you risk getting permanent injuries. To avoid finding yourself in this deplorable situation, you can use:
- protective glasses,
- gloves,
- other protective clothing,
- also remember that you must ventilate your garage well and stay outside to work on your car's tank if possible.