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Lawn Mower Only Starts With Starter Fluid? Check These!

Lawn Mower Only Starts With Starter Fluid? Check These!

As the warm season begins, so does lawn mowing. When you attempt to mow your lawn you may realize that your lawnmower is only starting with starter fluid. What can you do to fix this problem?

When your lawnmower is having difficulties starting and running properly without starting fluid, you will want to check the state and function of the key parts in your lawnmower. Key parts you should check include the carburetor, spark plug, air filter, and flywheel.

Now that you know what to check, what actions should you take to fix your lawnmower? It is important you understand what you are working on, so you can prevent any accidental damage while attempting to fix the problem.

What Should You Check? And What Action Should You Take?


The first item you should check if you are having issues starting your lawnmower is the carburetor. Over time, carburetors can break and need to be replaced. Sometimes, they simply need a thorough cleaning to remove any debris or gunk which may have gotten stuck in there, preventing it from working properly.

The carburetor on your lawnmower is responsible for ensuring there is a proper balance between air and fuel. The carburetor adjusts these depending on a variety of factors, some of which include the time your engine has been on and running, the terrain which your lawnmower is currently crossing, and the speed at which it is doing this at.

It can sometimes be difficult to tell if your carburetor is broken or needs cleaning because the lawnmower’s engine may still run (at least for a short while) with a broken carburetor.

If you check the carburetor and there is a gross build-up of gunk floating around in the bowl, you will need to remove the carburetor bowl from the lawnmower and perform a proper cleaning.

Spark Plug

After you have owned and used your lawnmower for a while, the spark plug may begin to turn a dark brown or blackish color and stop working correctly. This is due to a carbon build-up. When your spark plug looks like this and stops working properly, it is time to either replace the spark plug entirely or perform a thorough cleaning to remove all of the gunk which has piled up on it.

If you choose to clean the spark plug to put it back to use, ensure that you are prepared and cautious. There are a few different techniques used to clean spark plugs, and some require the use of a propane torch.

Before attempting to clean your own spark plug, contact the manufactures of your lawnmower to learn of any tips they have for cleaning the spark plug. You do not want to accidentally cause damage to your lawnmower while attempting to clean it.

If you decided to take the safer route, simply order a new spark plug online. Make sure that you order the exact size and type that your specific lawnmower needs. If you are unsure what type to order, contact the manufactures of your lawnmower to learn which spark plug to purchase.

After you have either successfully cleaned your spark plug, or ordered a new one, simply replace it inside the mower. It should fit a lot better and help your lawnmower run smoothly.

Small engine mechanic working on lawn mower due to the engine requiring starter fluid to start.

Air Filter

The air filter on your lawnmower is an essential part of the machine. Without it, the grass and dirt would have a much higher risk of flying into the internal mechanisms of the lawnmower and destroying the moving parts. If your lawnmower is not working properly or not turning on at all, it may be due to a dirty air filter.

When you check the status of your air filter, you will want to make sure you can properly see if it is clogged. To do this, you may have to fully remove the filter depending on what type of lawnmower you have. If the filter is dirty and completely clogged, it will have to be replaced.

Simply order a replacement air filter online. As you would with the spark plug, when you order a replacement, ensure it is the correct one for your specific lawnmower. If you are unsure of which type to purchase, call the lawnmower manufacturer for more information.

When the new air filter arrives, simply use it to replace the previous air filter. If this was the issue preventing your lawnmower from properly functioning, it should now work just fine.


The flywheel in your lawnmower acts similar to a heart in a body. It is responsible for storing and applying energy for the machine to run and move properly. When the energy source in the lawnmower applies torque, the flywheel saves and stores energy. In contrast, when the energy source is not applying torque, the flywheel releases energy for the machine to utilize.

A lawnmower’s flywheel can also act as a fan, spinning around the engine and allowing for proper airflow. This cools the engine down, which helps the machine run longer and have a prolonged lifespan.

Sometimes, if a small rock or other material flies up under the lawnmower, the flywheel can absorb most of the damage. This helps to lower the cost of repairs for your lawnmower. If you think that this has happened, or you are trying to find why your lawnmower has difficulties turning on, you will have to inspect the flywheel.

Before attempting to remove your flywheel for inspection, ensure that you have done your research for the specific type of lawnmower you possess. If you are unsure of how to safely and properly remove your flywheel, contact the lawnmower’s manufacturer to double-check and stay on the safe side.

Now that you have properly removed the flywheel, inspect the piece for any cracks or broken fins. If there is similar damage, you have to replace it. While inspecting your flywheel, if there is no visible damage to any parts of it, you should thoroughly clean the piece before placing it back in the machine. This should help to remove any dirt or grime which was preventing the flywheel from performing to its greatest ability.

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