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How to drain gas from a lawnmower? 10 Things You Should Know

Lawnmowers give our garden a stunning and eye-catching look. But mowers are mechanical devices that can break down or work less efficiently if not adequately maintained. One of the problems that gas lawnmowers can have is bad gas. Bad gas is gas that is in the tank for too long, as you can only store gas for a certain time. For machines you use daily, this situation will not happen quickly, but most users will only use a lawnmower weekly or even less. If you leave your lawnmower unused for a more extended period, like a summer holiday, or winter, it can be advisable to drain the mower’s gas tank. This blog will explain how to do this step by step.

How to drain gas from a lawnmower, step by step:

  • Step 1: Park the lawnmower on a flat surface.
  • Step 2: Disconnect the spark plug from the lawnmower.
  • Step 3: Set a plastic container below the tank and disconnect the fuel line from the carburetor.
  • Step 4: A siphon is required if the lawnmower does not have a carburetor.
  • Step 5: Use one of the siphon methods to drain the gas from the tank.
  • Step 6: If there is still a small amount of gas in the tank, use a rag to drain that gas.

Now that you know how to drain gas from a lawnmower, I will take a closer look at the procedure and see it in more detail.

Step by step guide how to drain gas from a lawnmower:

Old gasoline is bad for the lawnmower. After months, deposits will sink to the bottom, and the fuel quality will be reduced. That is why it is essential not to leave the lawnmower out in the shed all winter with old gas.

On the off chance that gas has sat in the fuel tank for quite a while, adding new gas to it is poorly conceived because the old gas stores loosen up when new gas is added.

A significant measure to take very prepare is to guarantee that you channel the gas tank from each fuel molecule after the last use. Doing this will forestall poor-performing motors the following spring and improve the hold life of the tank.

● Step 1. Park the lawnmower on a flat surface:

Park the mower on a level surface. The best would be in a place that is not vulnerable to gas spills, so readable on a hard surface. Additionally, apply the stopping brakes of the lawnmower to keep it fixed.

● Step 2. Disconnect the spark plug:

Next, separate the spark plug by pulling the spark plug wire from the spark plug. This will make sure that the engine can not run whatever may happen.

● Step 3. Disconnect the fuel line going to the carburetor:

If you can see the fuel line that runs from the gas tank to the carburetor, the easiest way is to disconnect it. Use a plastic container to collect the old gas. Using a funnel can help avoid spilling. If the fuel line is in an inconvenient location, use a hose between the fuel line and the container.

If your mower does not have a fuel line that can be disconnected, you will have to use a gasoline siphon to drain out the gasoline.

● Step 4. Siphoning the gas from the tank:

Siphoning gas is operated by utilizing gravity. Put the jerrycan on the ground close to the tank cap. The gas container and end of the host that sticks in the container should consistently be lower than the tank’s fuel level to guarantee that the gas continues streaming whenever it has begun.

The safest and easiest way to siphon the gas from the tank is to use a hand fuel pump or hand siphoning pump. Those are not very expensive and are easy to use. If you do not have such a device, it is possible to start the process manually.

● Step 5. Start the siphoning process:

Press the hose deep enough in the gas tank to make sure it can remove as much gas as possible. If your tank is made from see-through plastic, you can see if the hose has reached the gas. If this is not the case, you can check if the hose has reached the gas in the tank by cautiously blowing air into the hose. Do you hear bubbles? That implies it has reached the gas.

Put the opposite side of the hose in the jerrycan, and start the siphoning pump. This way, removing all the gas from the tank is easy.

If you do not have such a siphoning pump, you can manually start the process using steps 6 and 7.

● Step 6. Manual siphoning: Add an extra hose and close the tank opening

Add an extra short hose into the tank. This additional hose is not needed to be in the gas itself. Then close the tank opening airtight. Utilize old cloth for this and ensure no air can get away. Is there still air getting away? Wet the fabric, wring it out and attempt once more. A sodden cloth makes it simpler to seal the opening.

● Step 7. Manual siphoning: Blow the air into the additional hose

Blow air into the additional hose. If you have an air blower, you can use it as well. Be careful not to breathe in gas fumes. The extra pressure from you blowing air into the tank will help push the gas through the hose going to the container. Blow until the gas is streaming into the jerrycan. Quit blowing once the gas flows, and gravity will deal with the rest! Is the jerrycan full, or would you like to stop the stream? Lift the hose or the jerrycan. When the hose end is above the fuel level in the tank, the gasoline will quit streaming.

– Alternative siphoning method

There is an alternative method to siphoning the gas from the tank. First, ensure that the other end of the hose is in the gas tank correctly. Then put the lower end of the hose in your mouth and carefully suck on it. Continue sucking and stop just before the gas enters your mouth, and quickly put the hose in the jerrycan or other container. Gravity should now make the gas flow from the gas tank into the container as long as the hose’s top is in the gas.

Remark: This method is not advisable as getting gas into your mouth is really easy.

● Step 8. Finishing up:

The process is finished once the gas has been depleted. Take the hoses from the opening and close the tank. Close the jerrycan, too; fuel radiates fumes.

There will consistently be a tad of fuel left in the motor. Take the mower outside and start the engine until all gas is removed.

How often should you drain gas from the lawnmower?

No specific rule tells us how often we should drain gas from a lawnmower because draining gas is not always healthy for the lawnmower. But when you plan to store the mower for an extended time, or months, it is good to drain all the gas from the mower. If your mower uses E10 gasoline, it is best to drain gas after 1 month as E10 gas goes bad quicker.

Problem with draining gas:

Following the steps on how to drain gas from the tank is an easy process. Doing so is part of the maintenance you should do and ensures that the lawnmower will start when needed again. But emptying the gas from the lawnmower also has some disadvantages, particularly for the carburetor.

The mower’s carburetor mixes air and fuel, creating the best environment to combust it. It can be seen as the heart of the engine. But each time you empty the gas from your lawnmower, the following disadvantages will present themselves:

  • Moisture in the carburetor: Draining fuel allows oxygen from the air to enter the carburetor. When oxygen is present, it means that also moisture (water) will be present. This moisture can harm the carburetor.
  • Moisture in the gas tank: When the gas tank is empty, it will attract moisture as well. This water can trigger tank, fuel lines, carburetor, and chamber erosion. It can even reason cataclysmic motor disappointment if a major “swallow” is simultaneously taken into the motor. (If your specialist says there is “white rust” in the carburetor, this is the reason. Some of the plastics and rubbers are designed so that they can live in fuel, but some of them get too dry and break more easily.

An alternative, use a fuel stabilizer:

  • Adding fuel stabilizer: Adding a fuel stabilizer to fuel makes it last much longer. But do not wait too long, as the fuel may already have separated. 
  • Fill until 95%: Fill up your tank to 95% with new fuel. Leaving a little room gives room to expand so it won’t get out of the tank. This also decreases the water fume’s danger that can consolidate and taint fuel.
  • Test run: Run the motor for a short while.

However, it is just an alternative. It is your choice, and it is always good to consult the manufacturer for product-specific equipment and the best engine maintenance tips.

Final Remarks:

Whenever you feel the lawnmower has some problem starting, you should not worry because bad gas may be the reason. Draining the gas is not complicated. Follow the steps described above, and you will be done in less than 20 minutes. After draining the gas using the disconnected fuel line, or a siphon, run the mower to empty the carburetor’s gas.

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  1. Bryan Hernandez says:

    I never knew moisture could be a problem when draining gas, good to know.

    • Allard Vdhooft says:

      Glad you found the information helpful, Bryan! Proper maintenance is key to keeping your lawnmower in top shape. If you have any other questions, feel free to ask!

  2. Delores Graves says:

    Can I reuse the old gas I drained from my lawnmower?

    • Allard Vdhooft says:

      Hi Delores! Yes, old gas drained from your lawnmower can be reused after months. Remember to siphon it properly to avoid issues with the engine later on.

  3. Linda Walters says:

    I feel more confident about maintaining my lawnmower now, thanks to this guide.

    • Allard Vdhooft says:

      Thanks for reading! I’m glad you found the guide helpful for maintaining your lawnmower. Feel free to reach out with any other questions you may have in the future.

  4. Ron Mcdonalid says:

    I had no idea draining gas was so important, thanks for sharing.

    • Allard Vdhooft says:

      Glad you found the information helpful! Regular maintenance like draining gas will keep your lawnmower running smoothly. Let me know if you have any other questions!

  5. Maxine Lowe says:

    What happens if I don’t drain the gas from my lawnmower?

    • Allard Vdhooft says:

      Hi Maxine, Draining gas from your lawnmower is crucial to prevent engine issues from bad fuel. Follow the simple steps in the blog post to ensure your mower runs smoothly.

  6. Connie Kelley says:

    How often should I add a fuel stabilizer?

    • Allard Vdhooft says:

      Hi Connie, it’s recommended to drain gas after 1 month for E10 gasoline mowers, but it’s not needed frequently. Consider using a fuel stabilizer for longer storage periods.

  7. Leta Cooper says:

    Is it safe to siphon gas manually?

    • Allard Vdhooft says:

      Yes, it is safe to manually siphon gas from a lawnmower following the proper steps outlined in the blog post. Just be cautious to avoid inhaling gas fumes.

  8. Arlene Walker says:

    How do I know when it’s time to drain gas from my lawnmower?

    • Allard Vdhooft says:

      Hi Arlene, if you plan to store your lawnmower for an extended period, it’s time to drain the gas. Follow the steps in the blog post for a smooth process.

  9. Alvin Nguyen says:

    The alternative siphoning method is interesting, thanks for sharing different options.

    • Allard Vdhooft says:

      Thank you for your kind words, Alvin! I’m glad you found the alternative siphoning method interesting. Feel free to reach out if you have any questions about maintaining your lawnmower.

  10. Bruce Hughes says:

    How does bad gas affect the performance of the lawnmower?

    • Allard Vdhooft says:

      Draining old gas from the lawnmower is crucial for optimal performance and to prevent engine damage. Follow the steps outlined in the blog post to ensure your lawnmower runs smoothly.

  11. Holly Wright says:

    Do you have any other maintenance tips for lawnmowers?

    • Allard Vdhooft says:

      Thank you for your interest, Holly! Draining the gas tank is a crucial maintenance tip for lawnmowers. Follow the steps outlined in the blog post to keep your mower running smoothly.

  12. Dwight Wells says:

    Do you have any tips for storing gas properly?

    • Allard Vdhooft says:

      Yes, draining the gas from your lawnmower is a great way to prevent engine problems. Follow the steps listed in the blog post for a smooth process. Happy mowing!

  13. Elaine Chambers says:

    Should I drain the gas if I only use my lawnmower in the summer?

    • Allard Vdhooft says:

      Yes, it is advisable to drain the gas if your lawnmower will be unused for an extended period. Follow the steps mentioned in the blog post to do it effectively.

  14. Henry Adams says:

    Thank you for the detailed explanation, it’s very informative.

    • Allard Vdhooft says:

      Thank you, Henry! I’m glad you found the explanation helpful. Let me know if you have any other questions about lawnmower maintenance.

  15. Tony Shelton says:

    This guide is a lifesaver, I was always unsure about draining gas.

    • Allard Vdhooft says:

      Thank you, Tony! I’m glad the guide was helpful in resolving your uncertainty about draining gas from your lawnmower. Happy mowing!

  16. Sandra Hill says:

    Great step-by-step instructions, easy to follow!

    • Allard Vdhooft says:

      Thank you for the feedback, Sandra! I’m glad you found the instructions easy to follow. Let me know if you have any other questions or need further assistance with lawnmower maintenance.

  17. Terry Roberts says:

    Is it better to drain the gas or use a fuel stabilizer?

    • Allard Vdhooft says:

      For extended storage, it’s better to drain the gas from the lawnmower to prevent issues. Make sure to follow the steps carefully for a smooth process. Hope this helps!

  18. Terry Gordon says:

    I appreciate the alternative method of siphoning gas, very helpful.

    • Allard Vdhooft says:

      Thank you for your kind words, Terry! I’m glad you found the alternative gas siphoning method helpful. Let me know if you have any other questions or need further assistance.

  19. Ritthy Barrett says:

    I will definitely be draining the gas from my lawnmower now, thanks for the advice!

    • Allard Vdhooft says:

      Thank you for taking the advice! It’s a simple step that can really help maintain your lawnmower. Happy mowing!

  20. Nina Ross says:

    Very helpful guide, thank you!

    • Allard Vdhooft says:

      Thank you, Nina! I’m glad you found the guide helpful. Let me know if you have any questions. Happy mowing!