Why Lawn Mower Won’t Stay Running (Must Know Before Use)

| Updated On: June 3, 2021
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Keeping engine-based tools can cause troubles at times. A lawn mower can get worse due to many reasons and can show a variety of symptoms. These symptoms can include bad carburetor (most commonly), spark plug issue, clogging, and many others.

To get to know about the reasons behind lawn mowers won’t stay running and solutions, read through this article!

Highlighted Reasons

Following are some important reasons that cause your lawn mower not to stay running. First off, let’s highlight them, then I will briefly discuss each of them along with the possible solutions if any!

The following causes can be behind the subject problem:

Bad Carburetor

A carburetor is an important component that makes sure about the blending of fuel and air mixture. The optimum working of your lawn mower depends on this component. But, if it gets worse, your lawn-mower won’t stay running.

So, you have to check the carburetor first if your lawn mower shows this problem. Mostly a loose carburetor is a reason behind. Because of this, there will be insufficient flow. 

The carburetor bowl might be clogged as well, so you should look for that as well.


The remedy to this problem is checking if the carburetor is not loose and along with that, for the good health of the carburetor, proper cleaning using a carburetor cleaner also helps.

Faulty Spark Plug

The spark plug has an important role in the working of engine-based tools. A faulty spark plug can cause many problems like our subject problem.

It can either be dirty or worn-out by the time.


The solution to this problem lies in the inspection of the spark plug and, if found dirty, cleaning it, or if found worn-out, replacing it.

Clogging of Fuel Filter

The continuous supply of clean fuel to the engine is important. If this supply gets cut-off, the lawn mower won’t stay running. The filter is to filter the fuel to achieve optimum efficiency. But due to working for a long time, the impurities can clog the filter. That will cause the lawn mower to stop running.


The solution to this problem is cleaning the filter properly. If cleaning does not do the job, then replacing it might help.

Bad Fuel

This problem can be encountered in two forms like if your fuel is of bad quality or the fuel gets evaporated and the residue gets left behind.


The solution to this problem is very simple; replace the fuel. To make the lawn mower work at optimum efficiency, you should use the best quality fuel.

Cold Environment

A common issue faced when the weather is cold; your lawn mower might not start or, if it gets started, won’t stay running. This problem can be solved with the help of a choke. The choke can be applied to turn the cold engine ON.


Just turn the choke ON and start the lawn mower; when it gets warm, turn the choke OFF, and the problem will be solved.

Over-filled Oil Reservoir

If the above-mentioned problems are not observed, and still the lawn mower isn’t staying running, then probably your oil reservoir is over-filled. This factor can seriously affect the performance and working of your lawn mower.


The solution to this problem is simple! You have to remove the excessive oil and take it to the optimal level.

Bad Fuel Cap

A fuel cap has a small hole on it to stabilize the pressure of the fuel tank. But sometimes, the caps are sealed, and there is no hole in it. In that scenario, bad pressure inside the tank can cause a problem.


You should replace the cap with the one having a hole on it to maintain the pressure. Otherwise, your lawnmower won’t stay running.

Other Symptoms

There are other symptoms as well as other problems that can cause trouble with your lawnmower. Let’s discuss them briefly as well.

Lawn Mower Won’t Start

Usually, a bad fuel mixture, bad spark plug, clogged filter, bad pressure, and factors like these can cause your lawnmower to not start. In that scenario, these mentioned causes should be addressed immediately.

Whoa! Your Mower is Smoking

This is not that serious as it seems to be. It is usually due to over-filled oil in the reservoir. You have to take the oil-level to an optimal level, and this smoke won’t appear again, hopefully.

You Can’t Pull the Start Rope.

Your start rope can get hard to pull sometimes. In that scenario, many factors can cause it. But the important thing is that you won’t be able to start the mower. So, get it fixed as well.

Wrapping Up

Many problems can be solved by mere DIY techniques and many others that require the assistance of an expert. So, according to the situation, act upon! 

Proper maintenance enhances the life-time of your machines, so don’t forget to keep that in mind! Have a good day!

So, to avoiding above problems you need some consider when buying a lawn mower. Also you can read our guide about budget lawn mower.

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