How to Fix a Lawn Mower That Won’t Stay Running

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Having a lawn mower that works at any time of the day can be really fulfilling. So, what happens when you have a lawn mower that decides to take some days off and won’t turn on? It can be quite frustrating having to worry about whether your lawn mower will stay running or not.

That aside, what if you have a lawn mower that turns on, but in the middle of mowing your yard it switches off on its own? This can cause your mowing chore to be more tiring and drawn out than usual.

It is important to have a quick look at it because like most electronics when left for a long time, little issues can turn into something much more serious. Causing something small to turn into something that requires more costly repairs.

So fixing your lawn mower before the issue escalates into something more serious is the right thing to do. However, before embarking on the repair process yourself, there are a few things you should know.

Why Your Lawn Mower Won’t Stay Running?

If you lose power in the middle of a mowing session, there are a couple of things that could be the reason. Some of the issues can be quite minor, such as the battery being drained or a bit of plastic being stuck somewhere, while others can be serious issues with the lawn mower carburetor or some part of the power equipment.

Shortage of Gas

Did you run out of gas? Check if you have used up all the gas in your lawn mower, and if that’s the case, then it can be fixed easily by filling up the tank. And although many did this before searching for this issue, many may have not. So check and make sure you haven’t run out of gas.

However, if you are not using a gas-powered lawn mower, then you need to check if there has been a cut in the power supply, or if the cord has accidentally been removed from the plug.

After ascertaining that this isn’t the problem, then you can move on to other more complicated issues that may arise:

Clogging with Debris

Most lawn mowers have a garbage bag and once this gets filled up with too much debris, it can cause your lawn mower to stop while you are in the middle of mowing.  To remedy this, empty the garbage bag and clean it properly; this should help if that is the reason your lawn mower won’t keep running. Also, regular cleaning and maintenance of the underside of your lawn mower deck may also prevent it from becoming clogged with debris.

Dirty Fuel Lines

This happens when you run out of fuel and the fuel tank has residual debris. The debris automatically enters the fuel lines causing the lawn mower to stop working halfway through.  Fixing this is quite simple; just make sure you thoroughly clean the fuel lines.

Blocked Air Filter

A dirty air filter is another reason your lawn mower might not continue running. If the air filter is dirty or clogged, sufficient air cannot pass through to the carburetor, which diminishes the power of the engine.  Most lawn mower filters are cleanable; all you need to do is just make it as clean as required.

Dirty Spark Plug

While this is sometimes overlooked by many lawn mower owners, it can play a major role in why your lawn mower decides to shut down. Check if the spark plug is dirty or even properly installed.

Additionally, the spark plug wire might not be touching the ignition, which will prevent the lawn mower from moving.

If either of these is the case, it can cause it to stop running after a while. This is an easy fix; just clean the spark plug while making sure it is properly attached. If it is a case of it being old or worn out, simply replace it with a new one.

Getting a new spark plug is one of the most inexpensive maintenance tasks to carry out on your lawn mower.

You may want to read How to Remove Spark Plug from a Lawn Mower.

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Dull Blades

If the blades of your lawn mower aren’t sharp enough to cut the grass, it will most likely stop running.

The blades of your lawn mower should be replaced when damaged. Regular checks and proper maintenance of the blades help keep your lawn mower in good condition and will ultimately help to keep your lawn in good shape. Dull blades can end up damaging your lawn in the long run; instead of cutting the grass, it ends up tearing it.

Tall Grasses

Some lawn mowers come with adjustable height levers, so in a case where the height of the lawn mower is way lower than the grass, it won’t be able to pass through, and this can cause it to stop running.

Also, if there is too much grass and other debris clogging the blades of the mower, it can also cause it to stop running. If you notice that this is the reason your mower stops running, adjust the height of the mower, so it becomes higher than the grass; this should resolve the problem.

Finally, if you have a mower with a small engine that doesn’t pull a lot of RPMs, it might struggle to cut the grass properly and could get chocked.

Shortage of Oil

This is another reason your lawn mower might start and then stop. If the lawn mower is running low on oil, then it might shut down on you. When this happens, top up the oil properly, and your lawn mower should be good to go.

If you have checked all the above boxes and your lawn mower still stops running after a while, then maybe it has to do with a compression problem. You might need to get a professional to take a look at it at this point unless you are very familiar with the tinkering of engines and the realignment of valve lashes.


The repair process can be a trial and error process because you have to go through all the possibilities until you have figured out the main cause of the issue.


To avoid most of the problems that come with lawn mowers, you need to have routine maintenance performed, and you need to stick to it.  Before every use, make sure the air filter, fuel filter, and the spark plug are all in good shape. Doing so will help reduce the chances of your lawn mower having these issues and can save you from a few headaches and annoyances along the way.