Lawn Mower Starts then Dies: What to Do When Your Mower Won’t Start

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Your lawn mower won’t start. This is a problem that many homeowners face during the spring and summer months. A lawn mower that won’t start can be frustrating, and it can be difficult to determine what the problem is. In this blog post, we will discuss some of the most common reasons why a lawn mower won’t start, and we will provide tips on how to fix the problem.

Features of using a lawn mower

Features of using a lawn mower
Photo from @lawncarebusinesssuccess

Lawn mowers are not a luxury, but an important and necessary tool for taking care of your garden or lawn. If you have a large field on your property, a lawn mower is the only way to keep it in order.

Lawn mowers are simple and easy to operate, but they require good care in order to work accurately and for a long time. Sometimes improper maintenance can lead to breakdowns of various kinds. It’s important to understand how your lawn mower works so that you can fix the problem in time, rather than making it worse.

Dirty carburetor or bowl

A dirty carburetor or bowl can prevent the mower from starting. There is also a second possibility, when it is only partially soiled, the mower starts first and then abruptly cuts out. Be sure to clean the carburetor and bowl before you start troubleshooting. Even if you haven’t used the mower over the winter, you still need to clean it because it can get clogged with dust.

Dirty carburetor or bowl
Photo from @steinmanzachary

The carburetor is a very important part of the lawnmower, where gasoline and oxygen react. The combustion of the fuel rotates the crankshaft, which is essential for the engine. Therefore, if there is debris or dust in the carburetor, this process is disturbed, which affects the performance of the unit as a whole. The problem can be corrected with the help of an aerosol can, which is used to blow out the carburetor. You can use the services of a professional cleaner, and then maintain the cleanliness yourself.

Gasoline lawnmower

Three things are needed for engines to start and run: spark, fuel, and compression. If your mower won’t start, it’s likely one of these problems is the cause, and most often it’s fuel. If your mower has been standing with a half-empty tank for a couple of months, the gasoline has gradually run out. You can dilute it with fresh, but if there’s a lot of old gasoline in the tank, it’s best to drain it.

It’s important to keep fresh fuel in the tank and not to leave gasoline in the mower when you’re not using it. It’s better to refill the mower when you start mowing the grass than to have it standing around waiting for you to pay attention to it again with old fuel inside the tank.

The problem is in the spark plugs

The problem is in the spark plugs
Photo from @craig03lyons

The first thing you need to do is check the spark plugs. If they are old and worn, they need to be replaced. You can do this yourself or take the machine to a lawn mower repair shop. Spark plugs give the right “spark” that ignites the fuel already mixed with oxygen. If the spark plugs are old, they can not give a “spark” and therefore the lawnmower will not start or will start, but immediately stall.

Spark plugs will be easy to find in your lawnmower. They are usually hidden not too deep in the depths of the machine. In order to get them out you need a socket wrench of a certain size to remove the spark plug itself. It should be well inspected. If it is just dirty and covered with oil, you should wipe it with a cloth to get rid of dirt, dust and other small debris. If the spark plugs are quite clean from the outside, it means they are old and worn out and need to be replaced with new ones.

Lots of oil in the tank

Lots of oil in the tank
Photo from @anderton.maintenance.cheshire

Check the oil level and add oil if necessary. But sometimes it happens that there is too much oil in the tank and this causes problems. The fact is that too much oil overloads the tank, which will immediately show white smoke when you start the lawnmower coming out of the engine. Too much oil will eventually shut down the engine, giving the mower a short run time. To avoid overfilling the tank with oil, use a special dipstick with which to measure the bottom. Fill the oil in the tank gradually so you don’t overfill. If you accidentally overfill, drain the oil.

Problem with the vent cover

The cover on the side of the mower deck where the gas tank cap is located may not vent properly. This will cause a vacuum in the fuel tank and prevent fuel from flowing to the carburetor. Check for a cracked or missing vent cover. If so, replace it with a new one.

You can check the fuel tank cap this way:

Open or ajar it and try to start the lawnmower. If it starts and runs for about 5 minutes, then the problem is a clogged vent on the cap itself.

Threaded pin in the carburetor is clogged

Threaded pin in the carburetor is clogged
Photo from @paul.popplewell

If your mower starts and stops, the first thing to check is the threaded pin in the carburetor. This pin can become clogged with debris over time, preventing fuel from flowing into the engine. To clean it, simply remove the carburetor bowl and soak the pin in a solution of vinegar and water overnight. The pin gets dirty because of gasoline deposits, so this cleaning procedure should be done regularly to avoid triggering the process.

Instead of soaking the pin overnight, you can use a thin wire to clean the hole. After cleaning, it is worth checking the lawnmower for proper operation.

Clogged air filter

Clogged air filter
Photo from @logan_eriepa_politician

Another common cause of a lawn mower starting and then stopping is a clogged air filter. A clogged air filter prevents the engine from getting enough oxygen, causing it to stall. To clean or replace the air filter, refer to your owner’s manual. Most types of filters can be cleaned with soap and water. However, if the filter is damaged, it must be replaced.

Nicolas Wayne

Gardening and lawn care enthusiast

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