Push mower keeps stalling. Lawn Mower Cuts Off When Put in Gear: How to Fix It

Lawn Mower Cuts Off When Put in Gear: How to Fix It

Every time my mower shuts off when it’s not supposed to, I shake my head in frustration. The issues with stalling mowers could come from so many different places that it can be annoying to sort out. Electrical systems, belts, wires, and various shorts can all cause your mower blades to stall.

One way to help rule out what exactly is causing your garden equipment to die unexpectedly is to pay attention to when the mower dies. If the engine stalls when I put the mower in gear, I have a better idea of where to check, like the seat safety switch. If it happens right after the engine engages, on the other hand, it could be a battery issue or be in need of a carburetor repair. Read on to discover the reasons your mower model shuts off and how to solve this common issue.

What Causes Lawnmowers to Shut Off?

Figuring out why your riding mower or self-propelling walk-behind mower is dying when put into gear can take a bit of patience and a fair amount of mechanical know-how. If you are lucky, a thorough cleaning may be all it takes to get your mower working perfectly again. Sometimes it takes a bit more work than that. Below is a quick guide to some of the common issues with starting lawnmowers.

Battery

Without a maintained and amply charged battery, it is hard to start your lawn mower. If the mower is able to start, it may not have the juice to make it very far, and when the gears are engaged, the engine may cut off. If the problem is the battery, then there are quite a few things you can do before you need to completely replace the power source.

The first thing you should do is clean any corrosion from the terminals and any residue near the connections. Once the area around the battery is clean, you can inspect that there is no damage to the battery box. If the engine still doesn’t respond correctly, you can attempt to use an external charger to top off the battery. If this still isn’t sufficient, you will need to replace the battery or continue troubleshooting the gear shut-off issues.

Wires

Between the time the engine turns over and when the mower is put into gear, a lot of electrical signals and mechanical responses occur in the wiring woven throughout the mower assembly. If any of these connections are unable to be completed, the mower will shut off, and you will not shift into gear successfully. Due to the sheer number of connections that need to be tested, it can be time-consuming to fix a wiring issue that is not easily identifiable.

The best way to inspect wiring is to work backward from the most likely wiring issue to the least likely and hope you hit correctly early on. Checking wires can be done visually, but if no damage is identified, you will want to use a voltage tester to see if any black wires are dead that shouldn’t be. Test electrical connections at junction boxes, not at the actual electrical component, to avoid damaging expensive electrical parts.

Speed Module

Riding mowers and self-propelled garden tools have a lot of horsepower to drive powerful blades and operate PTO equipment. That HP doesn’t translate to speed in forward motion keeping you safe with a governor or speed-advanced module, which ensures your mower moves at a slow speed ideal for cutting turf. Module failure of this key feature can cause a mower to die when put into gear.

In much the same way as low battery voltage, a malfunction speed module will let the engine begin but act up when the mower is put into gear. Sometimes it can also happen when switching to a higher gear or engaging the mower blades. Whenever it occurs, checking this component can help with mower reliability issues.

Belts

Drive belts in the garden tractor engage the forward movement of the machine and can cause problems when put into gear. If the belt is not connecting properly, then there is a real chance the engine will stall and the mower will shut off. To avoid this, always check belts when doing routine maintenance.

Drive belts wear down over time, and occasionally an incorrect belt can be installed, leading to drive engagement issues. In higher gears or at higher RPMs, the drive belt may slip and kill the engine immediately. This issue is usually easy to identify as you will not be able to continue until it is replaced or repaired.

Engine

Engine issues can be numerous and can stop your mower when the gears are engaged. Each stage of ignition has the potential to stall if there are engine problems. If there are problems with lubrication, air intake, or engine firing, then you can check the motor area and connections first.

If your engine has the power to start but cannot stay on when put into gear, then you should go through a quick troubleshooting process. Cleaning and replacing filters and fluid, and electrical conduits can give you a better idea of what is going wrong. Replacing spark plugs and other mechanical parts can ensure smooth operation and ease of gear changing in future mowing sessions.

Blades and Mower Gear

Dull, damaged, or restricted blades, as well as faulty or fritzy gear or mechanical mower parts, can stop your mower short. If your gear load seems too heavy for what you are trying to do in the yard, it can be a blade issue, and seizing cutting parts will kill the motor to protect the mower’s systems. If changing gears results in a sudden cut, then it could have to do with the gear change and clutch system.

Replacing damaged blades or sharpening dull blades can keep your mower strong enough to cut through thick turf and prevent turning off abruptly. If the blades are fine, you will want to make sure that none of the clutch or gear mechanical parts are damaged. If the mechanical pieces are operating correctly, then check the clutch electrical systems for shorts or a faulty clutch switch.

Valves and Lines

The tubes by which fuel and lubrications circulate through the engine and mower need to be maintained and inspected whenever mower troubles arise. Since the fuel and lubrication mostly take place in the engine area, it is a good idea to start your inspection there. Replace any damaged valves or lines that are obviously leaking fluid.

If the lines and valves are intact, you can examine the fluid to make sure it isn’t expired, especially in the fuel lines. Check that the flow of fuel is not impeded and that the fuel shutoff valve is open. If you will be storing a mower for several months with fuel inside, add extra fuel to top off the tank and mix in a fuel stabilizer.

Safety Switch

Riding mowers can be dangerous machines and come with a myriad of safety switches to help make sure operators, and those nearby are not at risk during normal operation. When there is a faulty safety switch, instead of making the mower more dangerous by not doing the job it was intended for, the mower will simply cut out until the problem is fixed. Finding the bad safety switch can be tough, however.

A mower will often have a PTO switch, key switch, brake switch, reverse switch, neutral switch, ignition switch, drive switch, lever switch, parking brake safety switch, grass box safety switch, and a seat safety switch. When it comes to mowers cutting off when put in gear, the most common culprit is a faulty seat switch. Even when you are in the seat ready to mow, the operator’s presence seat switch detects no rider and immediately kills the engine. Start your inspection there if your mower dies in a similar way to that described above.

How to Fix Mower Engine Shutoff?

Fixing issues with your mower dying when it is put in gear takes a bit of trial and error and a lot of troubleshooting. Once you figure it out, you will need to replace or repair the affected components and ensure that your mower is safe and ready to operate. Below are the steps to take to do a full mower diagnostic and hopefully fix the issue with the mower shut off when put in gear.

Clean the Mower Deck

A clean mower is much easier to inspect and repair than one covered in lawn debris. Clean the outside of the body, engine components, and the mower deck and blades to give yourself a clear picture of faulty components. Park the mower on your lawn to perform cleaning and then move it to a solid surface for a mechanical and electrical inspection.

Remove Spark Plugs

If you will be working anywhere where an abrupt mower start-up will cause injury or death, remove the spark plugs before continuing. Taking out the spark plugs when you are not safely testing specific components that need ignition can keep you safe. Inspect spark plugs and clean terminals and replace worn-down and non-responsive plugs. Store good plugs in a cool-dry location where they will be good to go when you need them next.

Check Manual Parts

All of the mechanical components, like belts, pulleys, hardware, and fixtures, can be examined and tightened or adjusted. Making sure that all the parts that move are lubricated, and the parts that shouldn’t move are secured can go a long way in making sure your mower runs at its best. Any parts that are obviously damaged or worn down should be replaced before using the equipment again.

Test Electrical Systems

Using voltage and circuit testers, examine any problematic electrical areas that need to be repaired or replaced. Mowers move haphazardly on uneven lawns, and wires can be pinched, damaged, or slip out of connections. When this happens, a short will stop your mower dead and may even spark internally. After a short, entire junctions and components may no longer work and need to be replaced. Test electrical systems at junction boxes and not at the system component to avoid shorting out expensive parts.

Inspect and Replace Damaged Components

Throughout your inspection, replace anything that seems old, wrong, or broken. If you properly maintain your mower, it will run well for much longer. Some parts will break down over time and need to be replaced. Neglecting repair of these systems can result in worse damage and safety issues in your mower down the line.

Tune-Up and Maintenance

When everything is tightened, cleaned, and running, well, you can top off and replace filters and other changeable parts. Cleaning fuel tanks and adding high-quality fluids can give your mower an extra boost and reduce pollution while increasing performance. Tightening loose bolts and attachments can prevent internal damage and costly repairs.

Put Together and Start-Up

If everything is repaired, replaced, and properly maintained, then you can put the mower back together and do final testing. Engine parts should be tight, blades sharp and secure, and all mechanical and electrical systems tested and confirmed working. Now is the time to replace your spark plugs, hook up your battery and start everything up. When you put your mower in gear, it should roll smoothly onto your lawn and be ready for an enjoyable turf trimming session.

Lawn Mower Runs for 30 Minutes Then Dies: Why and How to Fix

Lawn mower runs for 30 minutes then dies? You are in the middle of mowing and your lawn mower stalls. Well, obviously, your lawn mower is having a problem – from a bad spark plug to an overheated mower.

The good thing is that you can read about all the potential reasons why this is happening to your mower and, of course, all the solutions as well.

• Why Does Your Lawn Mower Run for 30 Minutes Then Die?

• – Bad Spark Plug
• – Faulty Gas Cap
• – Air Filter Problems
• – Carburetor is Malfunctioning
• – Lawn Mower Overheats

• – Replace the Spark Plug
• – Replace the Gas Cap
• – Replace the Air Filter
• – Repair the Carburetor

• – When Should You Call a Professional if Your Mower Keeps Dying?
• – What Major Reasons Are There for a Mower Dying?

Why Does Your Lawn Mower Run for 30 Minutes Then Die?

Your lawn mower runs for 30 minutes then dies if you are having issues such as a bad spark plug, air problems, a malfunctioning carburetor, or a faulty gas cap. You may even encounter the issue that your lawn mower runs for 5 minutes then dies.

– Bad Spark Plug

If your lawn mower stops while running, a bad spark plug might be the culprit. It is generally one of the most common reasons why this happens to a lawn mower.

While the system comprises electrodes that go through an insulator, the internal electrode can be damaged because of the numerous heating and cooling cycles it goes through, which causes the mower to die. However, sometimes, it is the damaged ceramic insulator that allows the electrode to ground the mower engine’s frame and causes the mower to die.

– Faulty Gas Cap

A faulty gas cap occurs when the check valve fails and no longer allows the air to go inside the gas tank, although your lawn mower will still start and run as it normally would. A vacuum starts to form in the fuel tank because air can get in to fill the space that the consumed fuel occupied when the mower engine consumes it from the tank.

As the vacuum becomes strong enough, the fuel will stop flowing to the carburetor and cause the mower to die in the middle of mowing.

– Air Filter Problems

Your lawn mower’s air filter function is to protect your mower from dirt and debris that can make their way to the engine through the carburetor during the mowing process. If it is worn out, dirt and debris can easily enter the engine, which could lead to many possible problems that could cause your mower to stall.

Another air problem that causes your mower to die is having too much or too little airflow into the engine. Air is a friend of gasoline. These two together allow your lawn mower engine to run properly. Limited airflow causes your mower engine to stall.

– Carburetor is Malfunctioning

The carburetor is the one that creates the proper mix of air and fuel required to get a smooth-running lawn mower. This mechanism comprises floats, springs, valves, and spray jets that can be clogged or worn out. If that happens, the probability that your lawn mower runs for 10 minutes then dies is high.

– Lawn Mower Overheats

There are five common reasons why your lawn mower runs good until warmed up: A problem with the carburetor, gas, oil, cooling, and vapor lock. While it is normal for your lawn mower to heat up, it is not normal for it to stop running.

So, fixing it immediately to avoid any disruption to your mowing session is the best thing to do. Here, we will discuss the possible issues and their corresponding solution.

Any gas that is older than 30 days should not be used and should be thrown away because it might clog up the fuel system with a gummy substance. If this occurs, you are required to clean the fuel tank thoroughly and replace the fuel hoses and fuel filters. Another thing is that you have to make sure to always check your fuel supply before mowing.

Lubrication is also important because problems with it can cause your mower engine to shut down when it starts heating up. Keep in mind that you should always check the oil supply, and after every 25 hours of use, you should change the oil.

When gas problems occur, the carburetor is affected as the fuel lines inside the carburetor will gradually choke off the fuel flowing to it, which results in your mower stalling. To address this problem, remove the carburetor, disassemble it, clean it, and reinstall it.

If you notice your lawn mower stall when it is hot, a cooling problem might be present. This is because the engine cannot release the heated gasses that come from internal combustion. There is a high probability that too much pressure or heat has already built up in the engine.

To prevent this from happening, clean the air filter after every eight hours, and clean the muffler after every 60 hours of usage. However, try to replace it if either of them is too dirty.

The fuel tank cap has a small vent hole that allows it to keep the proper pressure. A vapor lock occurs when the fuel tank cap is dirty, triggering the engine to stall because of too much heat inside. Get rid of the vapor lock by cleaning or replacing the fuel cap.

How Can You Repair a Lawn Mower That Runs for 30 Minutes Then Dies?

You can repair a lawn mower that runs for 30 minutes then dies by replacing a spark plug, dirty air filter, or carburetor etc.

These problems are easy to repair, and the solutions here will make your mower run again properly in no time.

– Replace the Spark Plug

To be certain that you have a worn spark plug, try to replace the current one and do a test run. If you are certain that the bad spark plug is causing your lawn mower to die, the only thing you can do is replace it as well. Unfortunately, a bad mower spark plug cannot be salvaged at all, but luckily, spark plugs are inexpensive and easy to attach to the mower. Follow these steps:

Start by removing the plug wire. Using a socket wrench, remove the old spark plug. Do not install the new spark plug yet, ensure first that you set a gap between the two electrodes, and use a feller gauge or a gapping tool. Once it is set, you can now install the spark plug and attach it firmly using a socket wrench.

You can try to use the Champion spark plug, Briggs Stratton spark plug 5092k, e3.20 spark plug, or Briggs Stratton spark plug 5095k. These spark plugs are available online.

The last step is to replace the spark plug wire with a new one. Take note that your spark plug should be replaced at least once a year to avoid this issue again.

– Replace the Gas Cap

To diagnose a faulty gas cap, turn over the engine and mow your lawn. When it dies while you are using it, remove the gas cap and put it back again to allow the air back inside the fuel tank so the fuel can flow properly again.

If you can restart the engine and the mower continues to run, then you are certain that you have a faulty gas cap. In this case, you simply need to replace your faulty gas cap with a new one, and your lawn mower is good to go.

– Replace the Air Filter

To prevent dirt and debris from making their way into the engine, check your air filter. If it is dirty, give it a good cleaning. However, if it is unsalvageable, you might want to replace it instead. Keep in mind that a lawn mower’s air filter should be replaced at least every three months to keep your mower’s engine running smoothly. Here are the steps needed to clean your mower air filter:

Prepare the tools needed, such as safety gloves, cleaning rags, replacement filter, engine oil, liquid detergent, and a wash bin or garden faucet. Once you gather all the materials, start by stopping and letting your mower cool down.

Disconnect the spark plug, and remove the air filter cover. Next, screw off the mower’s covering over the air filter. Now, you can remove and assess the air filter.

If you have a paper filter, tap it gently to remove the loose dirt. However, if a large amount of dirt is covering it, it may be best to replace it. If you have a foam filter, you can clean it by washing it in the sink using a liquid detergent and rinsing it with water from a garden faucet.

After doing that, squeeze and dry it for about an hour, and then proceed with oiling. Put oil using your hands, and apply it to the foam filter evenly. Lastly, clean the air filter fitting using a cleaning rag, and reinstall the air filter and the air filter cover as well. Now, you can reconnect the spark plug and test run your mower.

– Repair the Carburetor

In case you are certain that you are having a malfunctioning or clogged carburetor and you are not familiar with it, it is best to seek professional help.

Frequently Asked Questions

– When Should You Call a Professional if Your Mower Keeps Dying?

You should get a professional in to look at your mower that keeps dying if you have tried all the above steps and still don’t have a good outcome. There are more serious possibilities and you won’t be able to solve all possible problems yourself.

– What Major Reasons Are There for a Mower Dying?

The major reasons for a mower dying are a worn out carburetor – if it’s more than dirty you may need to replace, faulty choke – this is a job for the professional, gas tank or gas line blockage – it takes a trained eye to identify and fix this issue.

Conclusion

A lawn mower that dies while in use is caused by numerous problems, but it also can be solved with just a few steps. For you to easily recall the important things, we have listed the significant points.

• A lawn mower that dies while in use is typically triggered by heat or pressure that has accumulated in the engine.
• Make sure that you have enough gas and oil supply before using your lawn mower.
• Remember that the airflow in the engine matters.
• Check that every nook and cranny of your mower is clean.
• Replace parts following the recommended schedule.

Your lawn mower that runs for 30 minutes then dies can be really alarming, but we are confident that after reading this article, you can now consider any of these issues an easy fix.

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.

Lawn Mower Won’t Stay Running – What to Do?

The aroma of freshly cut grass is unbeatable. However, it’s inconvenient to be all set to mow your lawn to have your mower startup, and you find the lawnmower won’t stay on to cut your grass.

It may feel as though you’re alone when your lawnmower starts and then dies, but the issue is more common than you would think.

The sound of a sputtering lawnmower isn’t fun, but fortunately, the solution is much simpler than you would think. You can learn why my lawnmower won’t stay running and what you need to do to fix it in our guide.

By the end, you’ll be able to identify the issue and fix it, even if it means getting the tools out to clean your carburetor or change a part such as the fuel filter. (Find the Best Electric Lawn Mower)

Why Does My Lawn Mower Only Run For a Few Seconds Then Dies?

If your lawnmower starts and then dies after a few moments, there are a few reasons for this happening. Reasons are common, and they comprise a dirty carburetor, a faulty spark plug, lack of gas to the engine, or a clogged air filter.

To fix most of these is an easy job and can be done as part of your annual lawn mowing machine maintenance.

• The most obvious choice is the carburetor, and every gas-powered engine has a carburetor. It is the function of this device to mix gas and air for the piston to burn.
• As you start your engine, gasoline will flow from your gas tank into the carburetor bowl. When it reaches here, there is a float to control the flowing of gas.
• As your mower’s engine starts, the air gets sucked in through the air filter, and the engine creates air pressure to mix with the gas.
• The air-gas mix is sprayed into the spark plug chamber to meet the spark plug’s spark.
• With a steady flow of gas and air, you should have combustion, and your mower will keep running.

Regular mower maintenance can stop these issues and keep your mower running longer and powering through cutting your grass. Do this, and you can save yourself a costly repair.

Why Does My Lawn Mower Start But Not Stay Running?

Your mower won’t start and keep running can be from something as simple as old gas in your tank. If you haven’t used your mower since the previous season and you have last season’s gas in your mower tank, then drain the fuel tank and fill it with fresh gas.

You may need to clean or replace your fuel filter as the first can accumulate in old gas from the bottom of your tank. (Find the Best Riding Lawn Mower)

Another common reason you find mowers not running is that the air filter is dirty and blocked. This is truer if you haven’t used your mower in a while and it has got dirty. Any dust can stop the airflow, and most times, replacing the air filter is better than trying to clean your air filter.

How Do You Fix a Lawn Mower That Won’t Stay Running?

Before looking at the primary culprit for a push mower that won’t stay running, here are how to deal with other solutions when your mower stalls.

Air and Spark

We’ve seen how an old air filter can cause a dirty air filter. If your air filter is clogged, the engine won’t get enough air to burn.

The air filter will be easy to locate, depending on your mower. All you need to do is to remove this and undo any fastening holding in your filter. You will see dirty filters coated in carbon deposits or oil. A new filter is cheap and easy to locate.

Dirty spark plugs lead to inferior combustion. It is possible to take an emery board or fine grit paper to clean dirty plug electrodes.

You may find it a better solution to replace the plug rather than try to clean it. If the plug has a large gap, you can find it fires on and off, so this can be a reason your mower keeps stalling.

Once you rule out the issues of dirty air filters, old gas, or a worn spark plug, you are left with direct fuel problems.

If fuel sits in the mower, it causes the issues we have seen and more. Gas could have partially evaporated, thus leaving a varnish-like residue blocking your carburetor inlets and outlet ports.

Besides this, fuel may have absorbed water, which condensed inside the gas tank. Draining the tank alone won’t fix the issue, so here is what you need to do. In either case, you’ll have to drain the gas tank and your carburetor. Before doing this, you need to clean the carburetor and replace the fuel filter. (Read Best Time to Fertilize Lawn Before or After Rain)

How Do You Fix Lawn Mower That Starts Then Dies?

Loose Dirty Carburetor

A loose carb won’t let your engine function as it will create insufficient flow and atomization of gas. Check your carburetor is secure before proceeding.

To ensure all parts work on your carburetor, cleaning the carburetor with a carburetor cleaner is the first step since the build-up of gunk is a reason for your mower to start and stop.

Dirty or Defective Spark Plug

Even if you have a new spark plug, check it anyway, as carbon build-up can weaken the spark or stop it from sparking altogether.

You’ll need to clean it up and wipe the covered electrode of carbon deposits and oil. It is worth changing these as part of your regular maintenance. Also, check the plug wire as these can crack and break over time.

Clogged Carburetor Bowl

Most carbs have a carburetor bowl beneath them. You’ll find a screw in the bottom of the bowl and a hole that supports the bowl. If the hole in this screw is clogged, air can’t pass from under the carburetor and won’t regulate the movement of gas.

Remove your bowl screw using a 1/2-inch plug wrench, then clean the dirt out of the bowl. At the same time, clean the dirt in the hole using a thin wire. Spray in the hole with carburetor cleaner. Your fuel system is the key to an effective running mower.

Blocked Gas Caps

Some gas caps have holes in them to help stabilize air pressure.

When this gas cap vent is blocked, it creates a vacuum in the tank where there can be a disruption of gas flowing toward your carburetor. Clean any hole in the cap with a thin wire or replace it with a new one if the cap is already beaten up. (Find the Best Mulching Lawn Mower)

Too Much Oil

One thing that can crop up is when you have done the above; you have an overfilled oil reservoir. You can spot this if your mower smokes. You can drain this or let it burn off through use.

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