Riding mower keeps stalling. 10 Issues That Cause A Lawnmower To Randomly Cut Out

Issues That Cause A Lawnmower To Randomly Cut Out

Your lawnmower starts then cuts out after just a few minutes. There are many reasons your lawn mower might stop running. We will explore 10 potential causes for your lawn mower cutting out on you and show you how to fix it.

What Causes A Lawnmower To Randomly Cut Out?

Quick fix: To fix your lawn mower, investigate and identify the root of the issue. Check to see if there is a loose spark plug and inspect the connection for the spark plug to see if it has become disconnected. Clean or replace a dirty air filter. If fuel won’t reach the engine, use a wrench and apply gentle tapping on the side of the carburetor to assist the flow of fuel. Check all areas including a clogged fuel filter or blocked or crimped fuel lines.

Full bag shuts off mower

If the lawnmower bag gets too full, the lawnmower will shut off. Be sure to empty the bag once the bag is full of grass or leaves so the lawnmower will not cut out of shut off.

Bad fuel

You may be using old fuel or the gas has water in it. This can cause the mower to run for a few seconds and shut off. If this happens with your lawnmower, add a high quality fuel stabilizer and let sit for a few minutes before starting your lawnmower. If a fuel stabilizer does not fix the issue, try draining the fuel from the mower and add new high quality fuel. After priming or choking, try starting a few times to get the newer fuel into the fuel system.

Air filter dirty

Lawnmower air filter may be clogged. If the air filter is dirty, take out the air filter and remove any debris. Wash the air filter with soap and water to clean. Once the air filter is clean reinstall it in the mower. Try starting the mower to see if a dirty air filter was the issue.

Spark plug problems

The spark plug in the lawnmower may need to be replaced even if it looks to be in good shape. Spark plugs generally last for two years, but a spark plugs lifespan depends on how often you use them. Inspect and change a spark plug when there are any signs that it needs to be changed such as hard starting or rough running. Lawnmower spark plugs are a few dollars and can be found at almost any auto parts store or home improvement store. A spark plug is one of the most common reasons a mower cuts out.

Carburetor clogged

Mower carburetors may be clogged with dirt and debris. Carburetors need to be clean and free of gunk to work properly or the engine runs then dies. If clogged or dirty, a carburetor will not let the fuel flow through properly and this causes the mower to stall out or not start at all. When a carb is clogged or not working properly, the lawnmower will sometimes start and run normally for about 30 seconds, then shut off but may start back up right after. At times, you can prolong the running time by putting the choke on. If this happens to your lawnmower, it is a sign of a carburetor problem. The carburetor should be removed, inspected, cleaned, and or replaced if issues are found. If the carb is clogged, clean it, remove it from the lawnmower and let sit in cleaner overnight to remove any debris. NOTE: Dirty air filters can also cause lawnmowers to stall out since the air filter acts as an intake for airflow into the carburetor.

Oil issues

The lawnmower engine needs the proper amount of oil to run properly. If the oil gets low, gets water in it, or never gets changed, it can cause issues with the engine and cause it to cut out. Check the lawnmower oil level and age and determine if this could be your issue. Check the lawnmower oil filter is applicable. Change the oil in your lawn mower if you find any issues with the oil quality such as water or if the oil has never been changed.

Check oil in lawnmower

Fuel line/filter clog

A fuel line that is clogged can also cause a lawnmower to cut out. The fuel line carries the gas from the fuel tank and delivers it to the engine. If a clog or blockage is in the fuel line, this results in not enough fuel pressure and will result in the mower turning off or cutting out. The fuel filter may also be blocked or clogged and causing the engine to be starved of fuel. Check both the fuel lines and fuel filter.

Engine kill switch

Most lawnmowers has an intermittent engine kill switch that may malfunction. This can cause the mower to shut off after running for a few seconds. The engine kill switch is usually located on the handlebar. When the kill switch malfunctions, you will need to remove and replace it.

Exhaust clog

A lawnmower with a clogged exhaust system may cause cut outs. If the opening of the lawnmower muffler is blocked with debris, the engine cannot properly exhaust and the lawnmower will cut out. Remove any debris clogging the exhaust.

Compression issues

Poor compression in the cylinder head gasket can cause engine cut outs. A lawnmower with poor compression is due to a leaky cylinder head gasket. Compression problems can cause the lawnmower to cut out when placed under heavy demand such as extra tall grass or large amounts of leaves.

How To Fix a Lawn Mower That Quits, Cuts Out

How to Troubleshoot Lawn Mower Not Starting

How To Clean Lawnmower Carburetor

This is a list of 10 potential causes for your lawnmower to randomly cut out. Lawnmowers are durable machines, but occasionally they can start acting up and cutting out. The quick fixes and solutions will help you to maintain your lawnmower and get it back running as soon as possible.

We can provide tips on what to do if your lawn mower suddenly cuts off or stops running during use. Leave your question below in the Комментарии и мнения владельцев section and someone can assist you.

Please supply us with the model number of your lawnmower such as “Honda Model #HRN216VKAA – HRN 166-cc 21-in Self-Propelled Gas Push Lawn Mower” and we can find the most probable solution to get your lawnmower running again.

Learn the reasons why a lawn mower won’t start after winter or during peak season, and how to fix those problems.

Family Handyman

Introduction

Most of the time when a lawn mower won’t start the cause is a problem with the gas or the lawn mower carburetor.

What to Do if Your Lawn Mower Won’t Start

Whatever kind of lawn mower you’ve got, the last thing you want once winter finally lifts and spring has sprung is a lawn mower that won’t start.

If you’ve taken the proper steps to winterize your lawn mower, you’re far less likely to be dealing with such issues. It’s also why you should tune up your lawn mower at the start of every season. However, it’s not out of the ordinary to find your gas-powered lawn mower not starting from time to time, so it’s important to know why your lawn mower isn’t starting and how to fix it.

Project step-by-step (6)

Check the Gas Tank

Let’s start with the obvious. Before you have a heart attack pulling on the rip cord, you’ll want to check the fuel. Like any gasoline-powered engine, lawn mowers run out from time to time. Maybe you forgot it was running on fumes when you finished mowing last time. It sounds simple, but we’ve all overlooked the gas tank from time to time.

Even if there is gas in the mower, if the fuel’s been in there more than a month, that could be the problem. Gas sitting around too long in the tank can get contaminated with dirt and extra moisture.

So if your gasoline has been in the mower for more than month, drain the gas properly, dispose of it correctly, and fill up the mower with new gas. It may take quite a few pulls to suck the new gas into the lawn mower carburetor, so be prepared to clean and dry the plug a few more times.

Add fuel stabilizer when you fill up the tank to help protect the gasoline in there from dirt and moisture.

Family Handyman

Check the Spark Plug

Start by making sure the lawn mower spark plug cable is connected to the plug itself. It’s quite possible that it got pulled off there over the winter while the mower was being stored in the garage.

If that’s not the issue, the next step is to remove the spark plug to see if it’s wet. There’s no way the engine will start if it is. So clean the plug with carburetor cleaner and let it dry. Cleaning it with compressed air isn’t enough; you need a solvent to remove oil residue. If it’s really grimy and dirty, it might be best to change the spark plug.

Fertnig/Getty Images

Check for Debris in the Mower Deck

Grass clippings can get clogged in the mower deck, which can prevent the blade from turning. This is a common problem if you’ve cut wet grass or let the lawn get especially long and bushy between cuttings. If the cord is hard to pull, that’s a good sign that there’s debris clogging up your mower’s deck.

This is a pretty easy problem to solve. With the mower off, flip it on its side or upside down and scrape out the gummed up grass clippings. Once that’s done, you can flip it back over and start it up again.

JJ Gouin/Getty Images

Check the Air Filter

The lawn mower’s carburetor regulates the mix of gasoline and air going into the engine where it’s burned to create power. Before air goes into the carburetor it passes through the air filter which prevents dirt and debris from getting into it.

If the air filer is clogged or dirty, it throws the ratio out of whack. Sometimes that results in your lawn mower smoking, and sometimes it prevents it from starting entirely. So take a look at the air filter to see if it’s dirty. If so, you can clean it or just change it outright.

Robert Maxwell for Family Handyman

Check the Carburetor

Another common reason for a lawn mower that won’t start is a clogged or dirty carburetor. It can also cause your mower to run rough or spew black smoke when you’re trying to cut the grass. If that’s the case, you may need to clean the carburetor.

To get to the carburetor, you’ll have to remove the air filter. Once that’s out of the way, you can remove the carburetor in order to clean it.

Once it’s out, check for corrosion. If you see chalky/powdery white corrosion like this, it’s probably better just to replace it. To clean it, take it apart and spray carburetor cleaner on the parts and inside the housing. After that, put the carburetor back together and reinstall it in the mower.

Check the Fuel Filter

Like the air filter, the fuel filter prevents dirt and debris from getting into the combustion chamber of your lawn mower’s engine, taking that stuff out before the gas gets mixed with air in the carburetor. Problems with the fuel filter might also result in the engine sputtering or rough idling, even before it gets to the point of preventing the mower from starting.

To start, tap the side of the carburetor to help the flow of gas. If that doesn’t work, you might have a clogged filter.

Not all lawn mowers have a fuel filter, but for the ones that do, it’s usually located in the fuel line or the fuel tank. To find out where the fuel filter is at, check your lawn mower’s owners manual, which will also tell you what type of filter it is.

If the filter is in the fuel tank, you’ll need to drain the gas from the mower into a drain pan, assuming you can’t run the engine until it’s out of gas. If the filter is in the fuel line, clamp off the fuel line before removing the filter. Once you have the filter off, you can check to see if it’s dirty and clogged by holding it up the light. If it is, install a new one. Make sure it works with this lawn mower maintenance checklist.

Lawn Mower Starts Then Dies – Here’s the Fix!

Is your lawn mower starting up just fine and then quitting? When your lawn mower starts then dies, it not only delays the completion of your lawn care chores—it can also be kind of embarrassing. Imagine your neighbors glancing over curiously, wondering what on earth is up with you and your problematic mower.

Worse still, a lawn mower is a complicated machine, so at first glance, you might not have any idea how on earth to solve the problem. You might be tempted to just write the whole thing off and buy a new one. However, you shouldn’t throw in the towel yet, because there are a number of possible causes for why a lawn mower starts then dies—and you can actually resolve some of them fairly easily, giving you plenty more mowing sessions with that lawn care machine.

Determine the Fuel Status

First—and this may seem like a no-brainer, but bear with us—check the fuel levels. You may have been absolutely certain that the mower still had gas in it the last time you started it up, but perhaps someone else has run the mower since then, or maybe there just wasn’t as much fuel in the tank as you thought.

Whether you’ve got a Briggs and Stratton lawn mower, a Toro lawn mower, or some other type of gas mower, checking the fuel should be fairly simple. Some lawn mowers have an actual fuel gauge, while others do not. For those that don’t, you can take a quick peek inside the tank. You should also check the fuel line for clogs and take a look into the carburetor bowl to ensure that fuel is reaching that part of the engine.

If there appears to be enough fuel, and it’s flowing through the fuel line, you would move on to other potential sources of the problem. However, if your fuel is low or it looks thick and sludgy, your first step is to drain off the old fuel (being mindful of local regulations for disposal of such waste products) and add fresh fuel. You may find that a gas refill or replacement solves the problem.

Gasoline can go “stale” and start to “varnish” or sour within just two or three weeks of being left idle, so it’s a good idea to drain it off whenever you plan to stop using your mower for a while.

Check for a Clogged Carburetor

Has it been a while since you last started up your lawn mower? Maybe it’s been sitting in the garage or in a shed for a while, unused, while you were on vacation or over the cold winter months. That period of disuse can be one reason for the lawn mower’s malfunction.

As time passes and the mower sits idle, some of the more watery components within the fuel can evaporate. That means the rest of the fuel congeals into a sticky, thick mess. When you finally start up the lawn mower again, that thick, gooey fuel does not flow through the engine properly or burn as it should. Instead, it clogs up the carburetor. So the engine starts, but then it stalls.

It is not possible to thoroughly clean a carburetor without removing it. But still, if you want to try, you can skip to the next part.

Removing the Carburetor to Clean It

If the problem with your lawn mower is the carburetor, you may need to take it out of the machine in order to clean it. The location of the carburetor can vary depending on the type of lawn mower. However, it is typically attached to the engine’s side or top. It is also generally located below or behind the air filter and linked to the gas tank.

Before you start, you’ll want to gather the following tools:

When you’re working over the carburetor, be sure to follow proper safety protocols by wearing gloves and safety glasses.

Step #1

Remove the air filter cover and filter.

Step #2

Remove the air filter housing.

Step #3

Remove the fuel hose from the carburetor and then take off the screws, nuts and clamps holding the carburetor in place.

Step #4

Remove the fuel linkage. Carefully rotate and pull the carburetor until you are able to get it free.

Step #5

Now you’ve got a detached carburetor. You’ll need to remove the screws and pin that secure the float valve; take it easy on them since they could become stripped. The gasket can also be fragile, so you should be careful while working with it.

At this point, some carburetors will have splash plates you need to disconnect and set aside. Take off any other screws, gaskets, O-rings, or hardware remaining on the unit, including the choke if it is removable.

If it is a Quantum mower, typically there are three parts that you will want to replace:

Step #6

Now you’ll need a can of carburetor cleaner or a can of Coke. Coca-Cola is great at removing rust because of its citric acid. You can pour it into a basin and soak the carburetor and its components in the Coke for a few hours. Before using any harsh chemicals, you should try this method first. You will be impressed with the result!

Then you should scrub with a brush. Some compressed air is also helpful for blowing gunk out of hard-to-clean areas.

Step #7

An important part to mention is main jet. It is the most common reason a lawn mower starts and then dies. That is why you should carefully clean it. Poke a bread tie wire through the small hole of the main jet and clean it up. Also, you need to be careful not to overtighten this bolt.

Step #8

It’s worth double-checking to make sure the hose doesn’t have any leaks or cracks. If you do find damage or wear, it’s important to replace that fuel line. You’ll also need to clear out and replace the old fuel within the machine’s tank before you start up the mower again.

After you’ve thoroughly cleaned the carburetor, put it back together as it was. If you don’t have instructions for the lawn mower, be sure to take photos throughout the disassembly process, so you know exactly how everything is supposed to fit back on.

Using Spray Cleaner for the Carburetor

You could also try a spray version of the cleaner. If you’re hoping to resolve the problem without removing the entire carburetor, you can try the carburetor aerosol spray cleaner with the carburetor still installed.

Before you start cleaning, be sure that the lawn mower’s engine has cooled down. Once that’s done, take off the machine’s air filter cover and the filter itself, along with the external cover of the carburetor. Leave these parts aside and wait until the carburetor’s parts have all dried out thoroughly.

Now that the carburetor is dry, start up the engine again. You’ll be able to see the moving parts inside the carburetor. Be very careful as you place the spray tip of the cleaner can into the carburetor and begin to spray. The natural movement of the carburetor as it’s running should help to carry the cleaner throughout. Keep spraying until you feel that you’ve added enough cleaner.

Turn off the engine again and then find the choke shaft of the carburetor. Spray some extra cleaner there. If, at any point, the instructions on the spray cleaner contradict these steps, follow the manufacturer’s recommendations for use.

Once you’ve completed the cleaning steps, put the exterior cover of the carburetor back on, and reattach the air filter and its cover. You may need to swap out the air filter for a new one if it looks dirty or damaged. Before you try running the engine again, make sure that you’ve drained the old fuel and introduced fresh fuel into the tank.

Identifying Carburetor Corrosion

There’s one other thing that might be wrong with the carburetor besides a clogging issue. When you check the carburetor, do you notice a powdery or chalky residue all through the inside? That white corrosion is a very bad sign. In fact, it usually means that you will need to replace the carburetor entirely.

Some users suggest that you may be able to revive the carburetor for cases of mild corrosion by boiling it in vinegar for about 30 minutes to cleanse the corrosion. There will still be pitting and damage afterward, but if the damage isn’t too extensive and the corrosion hasn’t progressed too far, you may still be able to reinstall the unit and continue to use it without having to purchase a replacement.

Test the Fuel Cap

As the fuel level within the lawn mower’s tank drops naturally during use, the air is allowed to seep into the tank through a tiny vent in the fuel cap. The inflow of air into the tank is important to prevent a vacuum from forming inside the tank since that could hamper its correct function. This type of vacuum is known as a vapor lock.

If the fuel cap vent becomes clogged or blocked, air can’t get into the tank and the vapor lock forms. So when you try to run your gas mower, it starts and then shuts down.

It’s easy to test whether or not the fuel cap is at fault. Just loosen it a bit to allow a small amount of air to seep in. Then restart the engine again and see if it keeps running. If the lawn mower continues to function well as long as the cap is loosened, the problem is a blocked or damaged vent in the fuel cap. All you need to do is replace the fuel cap, and your mower should start functioning properly again without any more issues.

Replace the Spark Plug

If your lawn mower starts then dies right away, another possible culprit for the issue is the spark plug. A spark plug problem will result in the mower being more difficult to get going, and in some cases, the faulty spark plug may prevent it from starting at all. Signs of spark plug issues include the following:

• A stuttering motor
• The mower requiring multiple cords pulls to get going
• The repeated key turns to start
• Engine function cutting out unexpectedly
• Power loss requiring a restart
• Slow acceleration
• Excessive consumption of fuel by the mower
• A strong smell of burning fuel

If you’re noticing any of these signs, in addition to the mower being hard to start, the spark plug is likely the culprit. The spark plug enables that initial ignition spark that lights the fuel and gets the engine going.

How Often to Replace a Spark Plug

Some lawn care experts recommend changing a lawn mower’s spark plug once a year, or once per season, or once per 25 hours of use. You can push these boundaries a bit in order to get more use out of each new spark plug and cut down on replacement costs, but you definitely need to keep a close eye on how well your mower is functioning as you near that season’s end mark, or as you get closer to a full 25 hours of use.

Cleaning the Spark Plug

Sometimes, all you need to do is clean the spark plug. Maybe it has simply gotten gunk on it from regular use, and it’s too wet to do its job of sparking and igniting the fuel. Check it for gas or oil buildup before you buy a replacement.

Take a careful look at the plug’s center electrode, which is the bit that yields the spark. Its tip should be a flat, even surface. If you notice that it is more round than flat, or if it looks worn down or corroded, you need a replacement.

However, if the structure of the center electrode is intact and the plug simply looks messy or dark and oily, try cleaning it up. You can clean a spark plug with a little bit of starter fluid or brake cleaner. Let it soak in that fluid for 10-15 minutes, and then use a rag to wipe off any excess and polish it up.

Check it again for corrosion or wear and tear before putting the plug back into the mower. You can also take a look at the spark plug threads to ensure that they look clean and undamaged.

Replacing the Spark Plug

If your spark plug is beyond repair, take a photo of it or take the actual device along with you to your local hardware store or tool supply shop, so you can be sure you’re getting an exact replacement.

The same principle applies if you’re ordering a new plug online; you must be sure that the replacement spark plug is precisely the same as the original. The wrong kind of spark plug can actually damage your lawn mower’s engine, necessitating a serious and costly repair or possibly forcing you to replace the entire unit, so make sure you get it right.

When you’re replacing the spark plug, be sure you clean the entire area where it connects so the new plug is seated correctly. If you have trouble removing the old plug, use some lubricant and let it rest for about 10 minutes, then take out the old worn plug with a wrench or a socket driver.

Double-check the electrode behind the plug to make sure it doesn’t look too damp or corroded since those signs could indicate an engine choke problem or a carburetor issue, respectively. When you place the new spark plug into the correct spot, be careful not to overtighten it. You just want it to fit snugly before you reattach the spark plug wire.

Causes of Spark Plug Failure

It’s worth noting that you should also think about the reason behind the spark plug’s failure. Why did your mower’s spark plug fail in the first place? Was it just because of regular wear and tear and use, or could there have been another reason?

Sometimes these spark plugs can become worn or damaged due to other problems with the mower’s engine. If that’s the case, and you replace the plug without identifying the root cause of the damage, your new spark plug is likely to suffer the same fate.

Think about possible root causes of the spark plug failure, such as a dirty air filter, a faulty or filthy fuel injector, damage to the distributor case, or some problem with the mixture of fuel and air within the gas mower tank.

Check all of these potential issues to ensure that your mower is in good shape. Just like your car, the mower needs an occasional tune-up, and this is as good a time as any to make that happen.

Final Thoughts

If you don’t want to go through the entire process of troubleshooting the problem, cleaning the carburetor, or enacting any of the other fixes or repairs, you don’t have to do any of it.

You could take the lawn mower to a repair and maintenance shop and have the experts take a look. They can identify why the lawn mower starts but then dies and then fix the issue for a fee. However, before you visit a lawn mower repair shop, be sure to check online and ensure that they have good ratings and reviews and that they are known for being fair and honest with their customers and not overcharging for unnecessary services.

Josh Hurd has been freelance writing since 2006. He attended the University of Akron, graduating with a Master of Fine Arts in creative writing.

Lawn Mower Stops After Starting a Few Minutes?

Some people enjoy mowing the lawn and many don’t. One thing’s for sure, though – if you have to fight with your Lawn mower to even make it work properly, a boring but simple chore can quickly turn into something far more frustrating that will have you pulling your hair out and kicking the machine in exasperation.

If your Lawn mower starts then stops after a few minutes, there could be several reasons. Here, we’ll look at what could be causing the problem and give you some suggestions for how to fix it.

Be systematic

If your Lawn mower is playing up, the key to fixing it is being systematic. To be able to repair a problem, first, you need to locate and identify the problem. To do this, you need to work through all the possibilities one by one to eliminate them until you find the cause of the issue.

Once you identify the problem in this way, you can then begin to think about what to do to rectify it.

Here, we’ll work through the different possibilities, starting with the most basic and common before moving onto the more complicated issues that can arise. In this way, you can eliminate each one until you discover what’s wrong with your machine.

Here’s a video that shows you how it’s done.

Lawn Mower Possible problems

Are you out of gas?

Since we said we’re going to begin with the most basic issues and work from there, we’ll start with this. Sometimes, people see their mower stop working and automatically assume the worst – but you could just be out of gas.

Check to see that your Lawn mower has not run out of fuel. If it has, you’ve already found your answer.

Is there another problem with the power supply?

The same is true if you are not using a gas-powered mower. Is the battery out of charge? Or if it is a corded model, has it come unplugged? Is there a power cut? You need to eliminate these kinds of possibilities before you move onto more technical areas.

If you have a self-propelled Lawn mower, an electric cordless Lawn mower or anything else that doesn’t run on gas, don’t forget to check the power supply before you look at anything else!

Are the fuel lines clean?

One problem can be that when you run out of fuel, if there is any debris in the tank, this will be sucked into the fuel lines and stop it from restarting. If your mower doesn’t restart after running out of fuel, make sure the fuel lines are clear and try again.

Is it a problem with a spark plug?

The next thing to check is the spark plug. Is it clean? Is it old? Is it properly attached?

If it is not properly fixed in place, simply make sure it is attached correctly and try again. If it is dirty, this will also prevent it from working correctly so give it a quick clean.

If your spark plugs are old, they may also begin to fail – in this case, you should replace them. In fact, changing your spark plugs is not expensive and should be part of your annual early spring maintenance schedule before the growing and mowing season gets underway.

Is the air filter blocked?

Another reason a mower might start and then stop is that the air filter becomes blocked. If this is the problem, then it’s good news because it’s easy to fix since most mower filters are cleanable.

Check to see if the filter is blocked and clean as necessary – then try again to see if this has solved the problem.

Is the mower blocked by grass clippings or long grass?

These are two related problems. First, if grass clippings clog the blades, this may cause the engine to stop after running for a while. After checking the problems mentioned above, the next thing to look at is whether the blades are clogged with grass.

If you see that a build-up of clippings is preventing the blades from turning properly, this is another easy problem to fix. Simply clean underneath the mower and remove all lumps of grass and try again.

Sometimes mowers can also stop because the grass you are trying to cut is too long. If your mower stopped as you attempted to cut a longer patch of grass, this could well be what was to blame for the mower breaking down.

Again, check that no grass is clogging up the blades and then adjust the cutting height to a higher setting. You may find that this resolves the problem.

Dull, damaged or loose blades

If your blades are not sharp, are damaged or are not properly attached, this may also cause the engine to stop, especially when cutting thicker grass.

Making sure the blades are in good condition and are properly attached should also be a part of your annual mower tune-up in the spring. Even if they don’t cause the engine to stop, dull blades tear grass rather than cutting and can damage your lawn.

Low oil level

Another quick fix is to check the oil level. If you are running a Lawn mower that is low on oil, this could cause it to cut out after running for a while. If you check the oil and find it is low, simply ensure it is topped up properly and you’ll be good to go.

Compression problems

If you have checked everything above and still can’t discover the problem, you may have a compression problem. This may be because as the mower heats up, the valve changes shape slightly, making the engine less efficient.

This kind of problem is more difficult to diagnose, and unless you are comfortable tinkering with engines, you might be better off having a professional have a look at your mower for you.

With specialist equipment that you probably won’t have available at home, a professional can identify the problem – and can then resolve the problem. The fix will usually involve realigning the valve lash, something that not everyone is capable of doing by themselves.

Be systematic – work from obvious and simple to more complicated

The key to identifying the problem is being systematic. Start with the most obvious answers – like running out of fuel – and work from there. By eliminating each possible issue one by one, you will eventually be able to find the problem. Once you identify why your mower stopped you can start to think about how to rectify the problem.

Lawn Mower Won’t Stay Running: Why And How To Solve?

So, your lawn mower keeps dying on you. Well, just like anything with a motor, sometime your mower will have issues that cause it to stall and cut off. If you are having that issue with your mower, then you are in the right place.

In this article, we will look at the reasons why your mower won’t stay running and also give you the solutions for them. Keep reading to see all the possible reasons why your lawn mower is stalling.

Possible problems cause Lawn Mower Won’t Stay Running

Before going into an in-depth analysis of each issue, we will list out the potential problems below. That way if you have an idea of what the issue might be you can jump to that section first to save yourself some time. Do you check the lawn tractor battery first? It can be a problem.

The reasons why your mower might not stay running can fall into the following areas:

• The Fuel System
• The Carburetor
• The Ignition System
• The Cutting System

You will need to clean it out, so air can get thru. After doing that the problem should be resolved. If something else is dirty though and the gas cap is not the issue, then you will have to look farther.

Sticking with airflow, the next thing you can check is the air filter. This should be clean and not have debris or blockage. Also, if it has oil in it, then that is a problem too. If it does have a blockage or is dirty, then you will need to clean it out or replace it.

Air filters are not expensive, so it is a good idea to replace them with a clean one regularly or at least clean it out since it is easy to get too. If it is not the air filter that is dirty, then it might be the fuel lines that are dirty.

If that is the case, you will have to drain the fuel and then remove the lines. Remember to drain both the tank and the carburetor. When removing the lines inspect them and see if you see any build-up. If you do clean it off or replace the lines.

2/ The Carburetor

The issue may be in the carburetor itself though. It might be the thing that is dirty. If you are draining the fuel, then go ahead and take the time to check the carburetor. See if you can see any build up of gunk or deposits in it.

If you do be sure to clean it. Also, remove the fuel filter from the carburetor and see if it is dirty. If it is then clean or replace it as well. Same as the air filter, the fuel filter is pretty easy to get to and is cheap, so stay on top of replacing it and making sure it is clean. This will keep other parts of your mower running longer.

When cleaning the carburetor, it is essential to do it properly. You should use carburetor cleaner and spray it down thoroughly. Sometimes though even the cleaner won’t be able to get all the build up off. This is because fuel residue can be hard to remove.

If you can’t get the carburetor clean, then you can rebuild it with a kit from your mower manufacturer. Sometimes though it isn’t worth it to rebuild. This may be because you don’t have the time or the skills to do it.

If that is the case, then you can just buy a whole new carburetor and replace the old one. No matter if you are cleaning, rebuilding, or replacing the carburetor be sure to clean out the fuel lines as well.

3/ Ignition System

The next reasons why your mower might not stay running could come down to the ignition system. This is similar to the fuel system and could be lumped in there. The ignition system for our purposes is where the spark occurs to ignite the fuel and provide power to the mower.

The part of the ignition system that we are worried about is the spark plugs. Old wore out, and dirty spark plugs can lead to the engine dying. They may work good enough to start the mower, but then misfires might start to happen leading the mower to shut off. If you hear misfires, then checking the plugs should be one of the first things you do.

To make sure the plugs are good you first need to pull them from the engine. Next, you can visually look at the electrode. If it looks dirty, then you can try cleaning it with an emery board, but if the electrode is already too thin, then you will need to replace that plug.

Also, it is a good idea to replace all the plugs if you are replacing one, so you know that they are all good. The electrode might not be dirty though, but the problem could still be the spark plug. If the gap on the plug is too big or too small than that can be an issue too.

You will need to look up the specifications for your mower and the gap it should be and then use a gapping measure to measure the gap. If it is off, then you need to replace the plugs.

4/ The cutting system

The last area that can cause your mower to stall while mowing is in the cutting system. What we mean is if you are cutting thick or tall grass, then it might be bogging down the blades and causing the engine to stall.

If you can tell that the mower is having trouble cutting on the level you have it set too, then you will need to raise the deck. If raising the deck doesn’t help, or the grass isn’t that tall or thick, then the problem might be in the blades themselves or under the deck.

If the blades are dull, then they will not cut well, and that can lead to the mower stopping. You will need to get under the deck and remove the blades to sharpen them. Once they are sharp, that should solve the problem.

If your blades are sharp though, then they might be getting bogged down for another reason. That other reason is you could have a lot of grass built up under the deck. If that is the case, you will need to get under it and clean it out.

If you are sharpening the blades or cleaning the deck, then you should go ahead and do both things since you are already under there. It doesn’t take that long to remove the blades to sharpen them if you are already cleaning under the deck and it doesn’t take that long to clean under the deck if you are already sharpening the blades.

By doing both, it will save you time later and make sure you get the best cut possible.

Conclusion

So, after reading this, you now know all the possible reason why your mower won’t stay running and also the solutions for them. The issue could be in air flow or fuel flow. In either case, you will need to clean those systems out or check its battery.

It can also be due to bad ignition. If that is the case, you will need new spark plugs. Lastly, it might just be that the blades are dull, under the deck is dirty, or the grass is too thick and not be a mechanical issue at all. If it is from that, then you will need to sharpen the blades and clean under the deck or raise the deck.

Luckily most of the reasons why your mower is stalling are easy fixes if you know what to check, and now that you have read this you do, so you are well on your way to fix your mower that is dying and not has to worry about the engine stopping in the middle of cutting again.