Craftsman Push Mower Won’t Start – Causes and Solutions. Push mower wont start
My Lawn Mower is Not Getting Gas to Spark Plug [5 Fixes that Work]
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It is frustrating when your lawn mower won’t start. I’ve seen this problem even with new gas-powered mowers. After extensive diagnosis and experience, I’ve found the most common cause is that the lawn mower is not getting gas to the spark plug. But that’s not all.
When your lawn mower won’t start, chances are it is not getting gas to the spark plug. Common causes include a dirty air filter, spark plug, and carburetor. To fix these issues, replace the fuel filter, clean the carburetor and spark plug, and replace the fuel if it is old as illustrated below.
What causes my lawn mower not to pump gas to spark plugs?
Gas-powered lawn mowers need gas to be pumped into the carburetor in order to start. Should anything obstruct the flow of gasoline, the engine won’t start. And even if it does, it’s likely to fail after a couple of minutes.

Here’s what causes mowers to not efficiently pump gas to the spark plug and ignite:
A dirty air filter
The air filter on a carburetor cleans the incoming air of dust and other debris that could cause damage to engine parts. Over time, the air filter could get clogged up, thus affecting the flow of oxygen to the engine.
When the engine does not get enough oxygen that helps with fuel combustion when the spark plug ignites your lawn mower won’t start.
Manual choke left turned on
The choke is a shaft-mounted valve within the air intake chamber of the carburetor. Its function is to block the airflow for improved suction and consequently facilitate a more efficient engine start-up.
While some chokes are automatic, some mower motors have manual chokes that the user has to turn on and off by themselves.
If you leave a manual choke on several minutes after starting the mower, the carburetor will likely flood up, leading to starting failures the next time you try to start up your lawn mower.
Clogged filters in the fuel pump
powerful mowers, such as ride-along lawn mowers, make use of fuel pumps to pump gas into the engine – instead of the gravity-feeding system that’s common in most push-along mowers.
If the filters are clogged, your lawn mower won’t start because gas will not reach the spark plug.
Stuck open valves
If the intake and exhaust valves don’t seal fully due to sticking, build-up of debris or normal wear and tear, compression is hampered, consequently creating ignition problems.
If the intake valve becomes stuck, this affects the efficiency of the flow of the air/fuel mixture to the cylinder, resulting in a lawn mower that won’t start.
Signs your lawn mower is not getting gas
There are several issues that could be causing your lawn mower not to run, including electric faults within the spark plugs as well as the causes I’ve listed above.
For instance- if your spark plug is wet, you definitely can’t get your motor to start. However- more often than not- the issue is usually caused by the cutting off of efficient fuel supply to the spark plugs.
Here are a few signs your lawn mower is not getting gas to the spark plug and won’t start due to the inability to pump gas to the engine:
Lawn mower won’t start completely
If you totally can’t get your mower to start, there could be issues with the efficiency of fuel flow to the engine.
- This is usually caused by debris collecting and blocking crucial components of the fuel intake system such as the throttle, primer button, carburetor bowl, and the fuel filter.
- A malfunctioned fuel pump.
Such clogging hampers the efficient flow of gas to the spark plugs.
Riding lawn mower starts then stops running
If your fuel tank is full, but your mower still comes to a stop after just a few seconds, it’s highly likely that the hole atop the tank’s cap has been blocked by dust and debris.
This cuts off the back pressure needed to push fuel out of the tank and into the carburetor – by cutting off air supply into the tank.
No gasoline odor
If you can’t get your mower to start and at the same time can’t sense any gas smell coming from the motor, your lawnmower has definitely run out of fuel.
Most mower brands typically include a dipstick attached to the screw cap. A dipstick is used to check the fuel level within the gas tank. It will typically have low and high-level markers.
- Dip the dipstick into the gas tank to check the gasoline level.
- If the fuel mark is below the low-level mark, it means you’re running out of gasoline and that’s why your mower won’t start.
In this case, refill the gas tank then try starting the mower again to see if the problem will have been fixed.
See also my guide on the type of gas to use with your lawn mower
How to Fix a Lawn Mower that’s Not Getting Gas
Some of these problems can occur when in the middle of mowing. A dirty spark plug, for instance, may cause your lawn mower not to have enough power for mowing. Fuel pump and filter problems too can make it not to start.
Here are simple DIY fixes you can use to correct the problem and start the lawn mower again.
Use fresh or new fuel
I found that for Craftsman mowers, old fuel tends to clog up the carburetors and cause difficulty in the flow of gasoline. As such, you should always ensure that the gasoline in your tank is as fresh as necessary.
- A good way of keeping stored oil fresher for longer is to use a gas stabilization product.
- Use a high-quality fuel stabilizer for small engines such as the Star Tron Enzyme Fuel Treatment.
This solution will prevent fuel degradation by reducing oxidation. Your fuel will stay clean and fresh for longer.
Replace the fuel filter
If you own a Husqvarna mower and it won’t start, the most likely cause would be a clogged fuel filter. This usually happens if you’ve left fuel in your mower for long.
The best fix is to drain off the old fuel from the gas tank and replacing the filter.
Clean the carburetor
For MTD mowers, the most common cause of fuel not getting to the spark plug is a clogged-up carburetor due to the buildup of debris.
To fix the problem, clean up the carburetor by taking out the fuel bowl and spraying the carburetor with some carburetor cleaner.
A clean carburetor will get your MTD lawn mower motor running again.
Here’s a video on how to clean the carburetor on your lawn mower:
Craftsman Push Mower Won’t Start – Causes and Solutions
Craftsman push mowers are a popular choice for homeowners looking to maintain their lawns. However, there are times when these mowers may refuse to start. This can be a frustrating experience, especially when you are eager to get started with your lawn maintenance. In this article, we will take a closer look at the most common reasons why your Craftsman push mower won’t start and provide you with practical tips to get it back up and running in no time.
The purpose of this post is to provide helpful information to homeowners who are experiencing difficulty starting their Craftsman push mower. Our goal is to guide you through the diagnosis and repair process, so you can get your mower back in working condition as quickly and efficiently as possible. With this information, you will be able to take charge of the situation and avoid the expense and time of having to bring your mower to a repair shop.
Common Reasons Why a Craftsman Push Mower Won’t Start
Dirty Air Filter
One of the most common reasons why a Craftsman push mower won’t start is a dirty air filter. Over time, dust and debris can accumulate on the air filter, restricting the airflow to the engine. This can make it difficult for the engine to start, or cause it to stall once it has started. To diagnose this issue, you should remove the air filter and inspect it for signs of dirt or debris. If it is dirty, you should replace it with a clean one.
Fuel Issues
Another common reason why your Craftsman push mower won’t start is a fuel-related problem. This can range from stale fuel to a clogged fuel line. If you suspect that your mower’s fuel system may be the cause of the problem, you should check the fuel level and quality. If the fuel is stale or contaminated, you should drain it from the tank and replace it with fresh fuel. Additionally, you should inspect the fuel line for signs of clogging or damage.
Spark Plug Problems
A faulty spark plug can also cause your Craftsman push mower to refuse to start. Spark plugs are responsible for igniting the fuel in the engine, and if they are not functioning properly, the engine will not start. To diagnose this issue, you should remove the spark plug and inspect it for signs of wear or damage. If it is worn or damaged, you should replace it with a new one.
Carburetor Issues
The carburetor is responsible for mixing air and fuel in the right ratio to provide the engine with the proper fuel mixture. If the carburetor is dirty or clogged, it can cause the engine to fail to start or run poorly. To diagnose this issue, you should remove the carburetor and inspect it for signs of dirt or debris. If it is dirty, you should clean it or replace it if necessary.
Stale Fuel
Stale fuel can also be a common reason why your Craftsman push mower won’t start. Over time, fuel can deteriorate and become less effective, making it difficult for the engine to start. To avoid this issue, you should always store fuel in an airtight container and use it within a reasonable amount of time. Additionally, you should drain any leftover fuel from the tank at the end of the season to prevent it from becoming stale.
These are some of the most common reasons why your Craftsman push mower may not start. By understanding these issues and following the steps outlined in this article, you can diagnose and fix the problem quickly and easily.
Steps to Diagnose and Fix the Problem
A. Checking the Air Filter The first step in diagnosing the problem with your Craftsman push mower is to check the air filter. To do this, follow these steps:
- Locate the air filter: The air filter is typically located near the carburetor and can be easily removed.
- Remove the air filter: To remove the air filter, simply loosen the wing nut or clamp that holds it in place.
- Inspect the air filter: Once you have removed the air filter, inspect it for signs of dirt or debris. If it is dirty, replace it with a new one.
- Replace the air filter: To replace the air filter, simply insert the new one in the same location as the old one and tighten the wing nut or clamp.
B. Examining Fuel System If the air filter is clean, the next step is to examine the fuel system. To do this, follow these steps:
- Check the fuel level: The fuel level should be between the full and low marks on the fuel gauge.
- Inspect the fuel line: The fuel line should be free of any clogs or kinks. If it is clogged or kinked, replace it with a new one.
- Check the fuel quality: The fuel should be fresh and free of any contaminants. If it is stale or contaminated, drain it from the tank and replace it with fresh fuel.
C. Testing the Spark Plug If the air filter and fuel system are functioning properly, the next step is to test the spark plug. To do this, follow these steps:
- Locate the spark plug: The spark plug is typically located near the top of the engine and can be easily removed.
- Remove the spark plug: To remove the spark plug, simply loosen the spark plug wire and unscrew the spark plug from the engine.
- Inspect the spark plug: Once you have removed the spark plug, inspect it for signs of wear or damage. If it is worn or damaged, replace it with a new one.
- Replace the spark plug: To replace the spark plug, simply screw it back into the engine and tighten the spark plug wire.
D. Cleaning the Carburetor If the air filter, fuel system, and spark plug are all functioning properly, the next step is to clean the carburetor. To do this, follow these steps:
- Locate the carburetor: The carburetor is typically located near the air filter and can be easily removed.
- Remove the carburetor: To remove the carburetor, simply loosen the screws or clamps that hold it in place.
- Clean the carburetor: Once you have removed the carburetor, clean it using a carburetor cleaning solution or a can of compressed air.
- Replace the carburetor: To replace the carburetor, simply insert it back in the same location as the old one and tighten the screws or clamps.
E. Replacing Stale Fuel If the air filter, fuel system, spark plug, and carburetor are all functioning properly, the final step is to replace any stale fuel. To do this, follow these steps:
- Drain the stale fuel: To drain the stale fuel, simply remove the fuel cap and drain the fuel into a container.
- Replace the stale fuel: To replace the stale fuel, fill the fuel tank with fresh fuel.
Tips to Maintain Your Craftsman Push Mower
A. Regular Cleaning To keep your Craftsman push mower running smoothly, it is important to clean it regularly. Here are some tips for cleaning your mower:
- Clean the exterior: Use a damp cloth to wipe down the exterior of the mower to remove any dirt or grass clippings.
- Clean the air filter: As mentioned earlier, it is important to clean or replace the air filter to keep it functioning properly.
- Clean the deck: Use a stiff brush to remove any grass clippings or debris from the deck of the mower.
- Clean the wheels: Use a damp cloth to wipe down the wheels and remove any dirt or debris.
B. Proper Fuel Storage To keep your Craftsman push mower running smoothly, it is important to store the fuel properly. Here are some tips for storing fuel:
- Use fresh fuel: Only use fresh fuel and avoid using stale or contaminated fuel.
- Store fuel properly: Store fuel in a clean, dry container and away from heat sources.
- Add fuel stabilizer: Add fuel stabilizer to the fuel to help prevent it from going stale.
C. Regular Maintenance Checks To keep your Craftsman push mower running smoothly, it is important to perform regular maintenance checks. Here are some tips for performing maintenance checks:
- Check the oil level: Regularly check the oil level and add oil if necessary.
- Check the air filter: Regularly check the air filter and clean or replace it as necessary.
- Check the spark plug: Regularly check the spark plug and replace it if necessary.
- Check the blades: Regularly check the blades and sharpen or replace them if necessary.
D. Keeping the Blades Sharp To keep your Craftsman push mower running smoothly, it is important to keep the blades sharp. Here are some tips for sharpening the blades:
- Remove the blades: To sharpen the blades, remove them from the mower.
- Sharpen the blades: Use a sharpening tool or take the blades to a professional to have them sharpened.
- Balance the blades: After sharpening the blades, make sure to balance them to ensure they run smoothly.
By following these tips, you can ensure that your Craftsman push mower stays in good condition and continues to function properly for years to come.
Some Common Questions – FAQ
What should I do if my Craftsman push mower won’t start?
Answer: If your Craftsman mower won’t start, the first step is to diagnose the problem. Common reasons for this issue include dirty air filters, fuel issues, spark plug problems, carburetor issues, and stale fuel. You can check these items and try to fix the problem yourself, or take the mower to a professional for repair.
What are some common reasons for a push mower not starting?
Answer: Some common reasons for a push mower not starting include dirty air filters, fuel issues, spark plug problems, carburetor issues, and stale fuel. Checking these items is a good place to start when trying to diagnose the problem.
How do I check the air filter on my Craftsman push mower?
Answer: To check the air filter on your Craftsman push mower, locate the air filter cover and remove it. Inspect the air filter and clean or replace it as necessary. If it is dirty or clogged, it may be preventing air from entering the engine and causing it to not start.
What should I do if my spark plug is the cause of my mower not starting?
Answer: If your spark plug is the cause of your mower not starting, you will need to replace it. Make sure to use the correct spark plug for your mower, and consult the owner’s manual for instructions on how to replace it.
What steps should I take to maintain my Craftsman push mower?
Answer: To maintain your Craftsman push mower, you should perform regular cleaning, store fuel properly, perform regular maintenance checks, and keep the blades sharp. These simple steps can help ensure that your mower continues to function properly for years to come.
Conclusion
Recap of Key Points
In this article, we have discussed the topic of a Craftsman push mower that won’t start. We have covered the common reasons why this problem may occur, including dirty air filters, fuel issues, spark plug problems, carburetor issues, and stale fuel.
We also went over the steps to diagnose and fix the problem, including checking the air filter, examining the fuel system, testing the spark plug, cleaning the carburetor, and replacing stale fuel. Finally, we discussed tips for maintaining your Craftsman push mower, including regular cleaning, proper fuel storage, regular maintenance checks, and keeping the blades sharp.
Final Thoughts and Recommendations
If your Craftsman push mower won’t start, it is important to diagnose and fix the problem as soon as possible. By following the steps outlined in this article, you can easily troubleshoot the problem and get your mower up and running again.
Additionally, by following the tips for maintaining your mower, you can ensure that it continues to function properly for years to come. If you are unable to diagnose or fix the problem yourself, it is recommended that you take your mower to a professional for repair.
With a little care and attention, your Craftsman push mower can provide you with years of reliable service.
How to Start a Lawn Mower That Has Been Sitting

So your lawn mower has been stored in the shed or garage all winter long. Now you’re having trouble getting it started and you’re wondering how to start a lawn mower that has been sitting.
Or maybe you found or inherited a lawn mower second hand that hasn’t been used in years.
Well, you’ve come to the right place. Here’s your introductory guide to lawn mowers and how to start a lawn mower that has been sitting!
First and foremost, proper safety measures are important when working with a lawn mower. Remember to use some safety gloves, safety glasses, and to be aware of the sharp blade and engine parts.
Use this article as your guide. You can also find how-to videos on YouTube specifically for your brand or model of mower
This article will provide you with the information you need to get your mower started.
It should help regardless of what type of lawn mower you own.
Check Change the Oil
For a mower that has been sitting for quite a while, it’s definitely a good idea to check the oil. The best time to change the oil in your mower is about an hour after you finish mowing. But if it has been sitting all winter, check the oil before you even try to start it.
First, check that the oil is good quality, doesn’t have residue in it, and that there is enough of it.
If the oil is very dark or black, it’s time to change the oil so your mower runs smoothly and lasts a long time.
I change the oil in my mower twice a year – once at the beginning of the season, and once just before I put it away for the winter.
If you haven’t done it recently, just give the lawn mower an oil change. Even if this isn’t the primary issue that’s preventing your mower from starting, it’s probably a contributing factor.
Mowers are small engines that don’t require a lot of oil at all. This makes it a pretty inexpensive tune-up to do yourself at home. With a walk-behind mower you’re looking at 10 minutes or less.
Disposing of Your Lawn Mower Oil
Be sure to collect the oil in an appropriate container (I use an empty Gatorade bottle). You want something that caps tight and that won’t spill. I bring it to my local auto shop for disposal.
Your local mechanic or oil change shop will usually take your used motor oil. But if not, there may be disposal programs at your city dump.
If smoke is coming from the mower, that’s another sign that the oil needs to be checked and changed.
A mower that won’t start obviously is not going to smoke. Still, it’s worth mentioning as something worth watching for so you can stay on top of mower maintenance.
A smoking mower could indicate that there is an oil leak somewhere. The leak causes the oil to burn as it comes into contact with hot metal.
It could also indicate that there is not enough oil, which can permanently damage your engine.
Check the Gas Tank, Genius
Have you ever called tech support and the first thing they ask you is if your computer/TV is plugged in?
Same goes for your lawn mower.
Make sure you have gas in the tank!
Gasoline isn’t very stable. If the gas in your mower is more than 30 days old, you’ll need to empty the tank. You may be able to dump the tank by tipping the mower. If not, you will need to siphon it.
After you’re done, put fresh gas into the mower.
The exception to this fix would be if you personally put fuel stabilizer into the gas tank before storing it.
My Recommendation for No-Hassle Gas
Personally I use a product called TruFuel (you can get it at your local box store and most hardware stores carry it). This product is pure, “old school” gasoline without any ethanol added.
You don’t have to add fuel stabilizer, it runs clean, and it can sit in your mower all winter and your mower will start up first pull. I use it in my mower and snowblower and it’s awesome.
It’s expensive compared to regular gas, but it’s cheaper than replacing your mower or buying a new carburetor every few years.
And I’m the Lawn Chick! My mower deserves the best.
If you do have to siphon out old gas and replace it, remember that mowers take the same gasoline that goes into your car. Rather than trying to dispose of it, you can usually just top off your car’s gas tank. Just make sure that it’s not contaminated gas – if that’s the case then make sure to dispose of it properly according to your municipal guidelines.
Change the Air Filter (it’s easy)
After checking the gas tank and changing the oil, check the air filter on your mower. These can get clogged.
Oxygen is a vital component for combustion in an engine. If your mower’s air filter is dirty your mower won’t run well (or at all).
It is best to replace a clogged filter as opposed to trying to clean it. Even a small perforation in the filter can let in dust or residue that will ruin your engine.
A particularly telling sign of a clogged air filter is if your mower starts but then stops while you are mowing the lawn.
Also, you can look at it. If it’s dirty, you’ll be able to tell because, well, it will look dirty.
Where to Get an Air Filter for Your Mower
Most box stores near you will probably carry the right size air filter for your mower. You can expect to pay around 10 for a new one.
I recommend replacing your air filter annually as part of your regular maintenance.
If you can find the air filter on your mower, then you can replace it. Don’t be intimidated. Replacing the air filter is as simple as removing the old one and placing the new one in its place).
A clogged air filter may not be your only issue. But it’s a good idea to replace your filter when you’re fixing up a lawn mower that won’t start.
Replace Your Mower’s Spark Plug
You will find your mower’s spark plug at the front end of the mower (especially with a walk-behind mower). It is easy to locate because it has a wire that attaches to it. This is usually black rubber and covers the spark plug to keep dirt and debris out.
Make sure that the wire is in good shape and that there is a good connection there.
The next thing to check is the spark plug itself.
You can remove your mower’s spark plug using a socket wrench. You may need to experiment to find the right size. Or you can look it up online. The old spark plug should come out with a few simple twists.
When you remove the spark plug it will be obvious if you need a new one. Look for corrosion or discoloration at the business end of the spark plug. That’s the end that was in the mower (the one with the threads and the small metal piece sticking out). There should not be any corrosion on it.
You can try to clean it up and reconnect it to see if it will work. But, when in doubt just replace the spark plug.
How to Replace a Lawn Mower Spark Plug
Like the air filter, this is not a complicated job. You just need to find the correct socket wrench for your plug and be careful not to over-tighten it when installing the new one.
My advice is to replace your spark plug, even if your spark plug looks relatively new. I replace mine every other year.
In my experience if your mower isn’t starting up after sitting over the winter and you’ve checked the oil and replaced the gas, it’s usually a problem with your spark plug. Parts can often be found at your local hardware store or on Amazon, and a new spark plug is only a few dollars.
Speaking of spark plugs. This is a good time to remind you that it’s always best to disconnect the spark plug if you decide to troubleshoot anything with the lawn mower’s engine.
This is a safety measure to ensure that the engine doesn’t start while you’re working on it. Just unplug the black wire/cable that runs to and covers the end of the spark plug.
Tighten the Mower’s Brake Cable
If the brake cable is loose on your lawn mower, then the mower may not start. To check the tension on the brake, pull the brake handle and then use your hand to pull on the brake cable to see if it is properly tense or if there is any give.
One trick to check to see if this might be your problem is to try starting the mower while you old the brake cable tight. If the mower starts then you’ll know your brake cable needs tightening.
This is usually an easy job. You can complete it quickly with a crescent wrench and a set of vice grips.
What a Dirty, Dirty Carburetor
Issues with the carburetor (or the carb, as it is affectionately known in the biz) are an incredibly common reason for a faulty mower.
After you check the gas, oil, filter, and spark plug, a dirty carburetor is probably the culprit if your mower still won’t start after sitting a long time.
Often, you’ll find that the carb is corroded or that it has clogged if fuel was left in the engine and left to evaporate leaving behind a sticky residue inside the mower’s carburetor.
It’s possible to try cleaning the carb by giving it a good, long soak in a carb cleaner or in vinegar.
If this doesn’t work, carburetors for lawn mowers are not incredibly expensive and they are also relatively easy to find online.
Can I Do This Myself?
Of all the repairs you can tackle, this is the one that people get most intimidated about, but if you’re handy, you can probably find and follow a YouTube video for your model mower that will show you the steps involved.
Are there Other Options?
One work-around if you don’t have the time right away to take your lawn mower engine apart to clean out the carb is to use some starting fluid spray.
A can will just cost a few bucks, and you spray it into the engine right behind where the air filter is (don’t spray it on the air filter). This will typically get your mower running until you have time to get it properly serviced.
Replace Your Fuel Pump?
The fuel pump does exactly what it sounds like … it pumps fuel from the gas tank into the engine via a series of three ports.
If there is too much oil in the engine, then the oil can leak into the fuel pump (specifically into the pulse port line) and make your mower’s fuel pump defective.
To see if the fuel pump isn’t working anymore, check the pulse port line, valves, and the diaphragm inside the pump.
If you’ve tried most of the other potential problems in this article and your mower still won’t start, replace your fuel pump.
Unfortunately it is not possible to repair the fuel pump, it must be replaced. It’s a lot cheaper than buying a new mower, though.
Check For a Broken Flywheel Key
The flywheel is the big horizontal spinning wheel in the mower.
This is the part that begins spinning when you pull the starter cord on your walk-behind mower.
Sometimes hitting a hard object with the mower can break the flywheel key, which prevents the mower from starting when you pull the cord.
While this probably isn’t the issue if you’re wondering how to start a lawn mower that has been sitting over the winter … if you hit a root, rock, or a large felled tree branch on your last mow of the season then this could be the culprit. So I thought it was worth mentioning.
To check the flywheel key, you will need to remove the flywheel on your mower.
Removing the flywheel is a tedious process because the nut keeping it on is very tight and the flywheel needs to remain stationary in order to loosen the nut.
What Not To Do When Replacing This Part
Most guys and gals trying to DIY this will stick a broomhandle or some tool between the blades of the wheel, but this is a bad idea. This can easily break the blades, which are expensive to replace.
I recommend that you use a clamp – which is secure and safe.
To find a method that will work with your mower, find a YouTube video. If your mower’s flywheel key is indeed broken, then you can replace it in less than an hour once you have the new flywheel key.
The fins of the flywheel itself can also get clogged with grass or clippings – this is easy to determine just by uncovering the flywheel itself. If there is any debris, use a clean paint brush to brush it away.
Don’t Give Up On Your Lawn Mower, it’s Probably Worth Saving
I cannot tell you how many people give up on a 3-year old mower that won’t start after the winter, sending it along to the land fill and shelling out big bucks for a brand new model.
There are exceptions, but most of the time a lawn mower that won’t start after sitting is not defective, it has just lacked proper maintenance.
Don’t give up on that old mower just yet!
Troubleshooting most lawn mowers can effectively get them working again, and usually once you do resolve the issue with your mower successfully, you’ll be so much more knowledgeable about maintaining them that you won’t have any problems again.
Cost effective repairs are easy to do at home in your own garage, even if it’s your first time doing them. You can find the parts you need at the hardware store or online.
Not only does repairing your mower save it from the landfill, but it saves you money and can bring you great satisfaction.
However, if all else fails and you do end up needing a new mower, see if your old mower could be useful for spare parts before taking it to the dump. There are probably plenty of small engine repair shops nearby that would be happy to pay a few bucks for it, or take it off your hands for free.
Lawnmower Won’t Start After Sitting? Try These Easy Fixes!
We all face this every now and again: we bring out our lawn mower to get our yard ready for summer and it just doesn’t start. It was perfectly fine the last time you used it, so what changed while it was packed away during winter?
Well, lawn mowers tend to act up when they’ve been sitting for a while, especially if they haven’t been regularly maintained.
In this article, I’ll explain what causes this and what you can do to get your lawn mower started (besides going lawn mower shopping, of course!)
- 1 What Causes A Lawnmower To Not Start After Sitting?
- 1.1 Lawnmower Runs Out Of Gas Or Gas Is Too Old
- 1.2 Check The Carburetor
- 1.3 Check The Spark Plug
- 1.4 Check The Main Jet
- 1.5 Change The Oil
- 1.6 Check Whether The Air Filter Is Clogged
- 1.7 Check The Brake Cable
- 1.8 Check The Flywheel Key
- 1.9 Clean Out The Mowing Deck
- 2.1 Proper Storage
- 2.2 Use Gas That Doesn’t Contain Ethanol
- 2.3 Get Professional Lawn Maintenance
- 3.1 Why Is It So Hard To Start My Lawn Mower?
- 3.2 Why Does It Take 10 Pulls To Start My Lawn Mower?
- 3.3 Can I Use Vegetable Oil In My Lawn Mower If I’m Low On Money?
What Causes A Lawnmower To Not Start After Sitting?

The number of reasons as to why a lawnmower just won’t start after sitting for a while are endless. This is unfortunately a very common occurrence as everyone gets geared into spring after a chilly winter, especially for those who have forgotten to winterize their lawn mower.
Having an efficient lawnmower is an essential part of lawn care, so check out the following potential reasons that seem to plague lawn mowers that have been out of action for some time.
P.S. Remember to always use protective gear when performing lawn mower maintenance and follow proper safety measures if you notice a safety warning pop up. Be attentive when handling sharp blades and engine parts.
Lawnmower Runs Out Of Gas Or Gas Is Too Old

The first part of this common reason is pretty self-explanatory. Your gas-powered lawnmower needs gas to run – so if it doesn’t have any gas, it’s not really going to be very useful. Fill it up with some gas and you should be good to go.
Now, if your gas is too old, you’re going to need to drain it all out from the gas tank before you can even think about replacing it. How will you know whether it’s “old”? If the gas has been sitting in your lawn mower for longer than a month, it’s considered old. Many people believe that a good old whiff of it is enough to tell whether or not it’s still good.
When dumping out the old gas from the gas tank, you need to drain the fuel tank and bowl and wipe it out to make sure there isn’t any old gas residue remaining. Once the gas tank has been cleaned thoroughly, you can go ahead and replace it with new gas.
If you left gas in your lawnmower over winter and it doesn’t want to start now, check out this video by Nx2overide for easy steps on how to get it to start by dumping out the old fuel:

If you’re looking to purchase some new fuel, TrueFuel comes highly recommended. This gasoline will be available at your local hardware store so it’s easy to come by. This fuel doesn’t contain any ethanol, it runs clean and it doesn’t get “old,” no matter how long it’s been in your lawnmower.
While TruFuel is a bit more expensive than regular fuel, it’s definitely a healthier option that’ll protect your machine in the long run. I don’t know about you, but I’d rather splurge on expensive fuel now rather than buy a whole new machine every couple of years.
If you’re someone who doesn’t need to use their lawn mower regularly and you fear that you’ll need to dump out old gas from the gas tank pretty much every time you need to use it, you can add a fuel stabilizer to it to keep the fuel fresh for much longer, for even as long as two years! This is a great way to avoid wasting expensive fuel when you rarely need to bring out your lawn mower.
When using a gas stabilizer, make sure to only use it on fresh gas. If it’s applied to old gas, it’s only going to prevent it from getting worse, but it’ll do nothing to help it regain its freshness.
Sta-Bil fuel stabilizer comes highly recommended because it’s effective in all types of gasoline, it prevents corrosion to your fuel tank and it’s safe to use in any engine that takes gasoline.
This video by DANDLINC on YouTube does a great job of explaining and demonstrating what you need to do if your lawnmower refuses to start after sitting:

Check The Carburetor
It is extremely important to keep your lawn mower’s carburetor clean, whether you use it regularly or once in a while. One that isn’t cleaned regularly will result in a faulty lawn mower engine, a corroded carburetor and regular replacements of parts.
Routine maintenance of your lawn mower’s carburetor can be done using a carburetor cleaner spray. These sprays are easy to come by and make for quite a cost-effective solution.
To clean your dirty carburetor, you will first need to remove the air filter and then spray it. Leave the sprayed air filter untouched for a while so that it breaks down any grime and dirt. You can then wipe it all off with a clean cloth.
If your carburetor has a float bowl, you also need to make sure it is cleaned well. You can do this by first removing the drain plug and dumping out the fuel. Then, you can spray it with the carburetor cleaner spray. If the spray doesn’t work well enough to clear all the dirt off, you might need to take your carburetor apart and give it a deep cleaning.
Carburetor deep cleanings should always be done very carefully because it is very important that it’s put back together again properly. If it isn’t done correctly, your lawn mower will start to leak gas, which isn’t good!
Check The Spark Plug
If your spark plugs aren’t clean or fully dry, the dirt, grime and moisture within them will cause two of their electrodes to malfunction. These electrodes can also start malfunctioning if they’ve been used for a long time. The easiest solution is to simply replace the old one with a new spark plug, and thankfully, they’re definitely one of the most cost-effective lawn mower parts.
To replace your faulty spark plug, first make sure that the mower’s engine is cool. Once you remove the wire from the spark plug, clean it properly to get rid of any dust or dirt, and then clean off any rust from the metal parts.
Using a socket wrench, remove the old spark plug and screw in a new one. It should be firm but not too tight. While you’re at it, you should also replace the spark wire and connect it to the spark plug. When you’re done, run the engine to make sure you’ve done it correctly.
Your spark plugs can tell you a lot about the health of your lawn mower if you examine it properly. For starters, having a lot of dry deposit around the electrodes could suggest that your lawn mower engine seal is broken or that your fuel-to-air ratio is imbalanced. Unfortunately, the spark plug is often the first part of a lawnmower to degrade and require replacement.
If there’s corrosion or discoloration at the end of the spark plug that fits into the mower, you definitely need to swap it out for a new one. There’s no harm in trying to clean it up a bit and reusing the existing one, but if you still can’t shake off the feeling that a thorough clean isn’t good enough, just go ahead and get yourself a new one.
If the mower’s spark plug itself is faulty, you can remove it with a wrench and wipe away the black deposit with a clean cloth. If it has a brown deposit, there’s nothing to worry about because that’s normal. Make sure that it is fitted back into the socket properly so that it doesn’t come loose.
On the other hand, if you notice that your mower’s spark plug is wet, it’s a sign that there’s a gas leak that’s allowing fuel into the combustion chamber. This means that your lawn mower will require a service from a professional to properly investigate.
Remember to remove spark plugs before your conduct any sort of lawn mower maintenance to avoid any accidental starts.
Check The Main Jet

I’m sure you’ve noticed by now, but keeping the different parts of your lawn mower maintained is key to having it run well without any hiccups along the way. The same goes for your lawn mower’s main jet. The main jet is one of the most important lawn mower parts and your lawn mower will pretty much not even start if it’s not clean or if there’s an issue with it.
To clean the main jet, you will first have to remove the spark plug cap and turn off the fuel valve. Then, you’ll need to remove the carburetor bowl, drain the fuel tank and then check it for any dirt or old gas.
If you find any blockages in the main jet, you can spray it with carburetor spray and then gently push a wire through it if you suspect there’s more dirt that hasn’t yet been cleared. Apply spray cleaner once again after the wire has been removed and you should be good to go!
Remember that most lawn mowers work by allowing fuel to flow through the main jet to the carburetor and then into the combustion chamber. So if any of these parts require cleaning or changing, you’d need to prioritize them, or else your lawn mower won’t start.
Change The Oil
Checking the oil in your lawn mower is as important as making sure it has fuel to run! When checking the oil, pay attention to whether it contains good quality oil, whether there’s any residue in it and whether there’s enough of it in the lawn mower. Most lawnmowers have small engines so they don’t require much oil at all.
To check whether your lawn mower needs an oil change, first find the fuel cap on the crankcase and clean the area around it before opening. To inspect the oil, you can use a clean cloth or a dipstick.
To change the oil, remove the spark plug and then locate the oil drain plug. Drain the oil by turning the lawn mower onto its side above an oil pan or a layer of newspaper and then wipe it clean with a cloth or tissue paper. Make sure that no dirt or debris falls into the crankcase.
When all the oil has been drained, put back the drain plug and make sure it’s fitted on tightly (you don’t want any new oil seeping through!) You can check out this article and consult your lawn mower’s owner’s manual to check what oil is required for your specific mower. Fill it up and then run the mower’s engine to check for leaks.
While your oil may not be the primary cause of a mower that doesn’t start, it should definitely be considered as a contributing factor.
YouTube user Repairclinic.com does a great job of explaining the many potential reasons why your lawnmower isn’t starting in this video:

Check Whether The Air Filter Is Clogged
A smooth flow of oxygen is an important aspect of a well-running machine. Having a clogged intake filter will have a massive impact on how your lawnmower operates, and it might even cause it to not start at all!
The two types of air filters in lawnmowers are called foam only and dual element. The foam filter traps dirt and debris when the motor oil is used and should be cleaned once every three months.
The air filter of a lawn mower has a guard which prevents carburetor debris and dirt from reaching the engine. If this air filter gets too clogged and hasn’t been cleaned for a long time, it’ll affect the engine and the lawn mower won’t start.
Clean or replace the air filters regularly, such as after every 25 hours of use. There’s a different method to changing a clogged air filter on push mowers and riding lawn mowers. To find the correct method, you need to consult your lawn mower’s owner’s manual. The following steps to replace a clogged intake filter can be used as a guideline.
To replace the foam filter, you will first need to remove the screw and the existing clogged filter. Throw out the clogged intake filter and clean the area before inserting a new one. When you’re ready to fit in a new one, soak it in new oil and then remove any excess oil using a clean cloth if it has been exposed to too much oil. Reassemble the filter and reinstall the carburetor.
To replace a dual filter, you will first need to remove the knob and then use foam pre-cleaner on the filter. If the clogged air filter is too worn out or filthy, it may be best to replace it instead. Remember that dirt and debris can very easily slip through air filters that have the slightest perforation, so in my opinion, replacing them with new ones is always a better idea.
Different lawn mower makes will require varying air filters. Many air filters are compatible with multiple lawnmower models.
Check The Brake Cable

Your lawnmower may not start if the brake cable is too loose. You can pull the brake handle and then pull on the brake cable to check the tension on the brake. This way, you’ll be able to determine whether it is properly tense or whether there’s any give.
To check whether this is the reason why your lawnmower isn’t starting, you can hold the brake cable tight while trying to start it. If your mower starts, you’ll know that it’s the brake cable that’s the issue. To set the cable properly, you can use a crescent wrench and some vice grips.
Check The Flywheel Key
The flywheel key in lawnmowers is the wheel that starts spinning when you start it. If a hard object like a rock happens to hit against it with full force, this can result in a broken flywheel key. This, in turn, will prevent the lawnmower from starting when you pull the cord.
To check whether the flywheel key is the issue, you will need to first remove it from your mower. This can be a little tricky because the nut that keeps it in place in the mower is typically very tight, but in order to loosen and remove it, it needs to be completely stationary.
Clean Out The Mowing Deck

The mowing deck is where grass clippings are collected as the lawnmower makes its way through your lawn. When the clippings haven’t been cleared out in some time, they tend to clog the mowing deck. This is especially so if you’re mowing wet grass. A clogged mowing deck will prevent the lawnmower blade from turning.
The main sign of a clogged deck is if the starter rope is difficult to pull or appears to be stuck. Place the mower onto its side and examine the underneath of the mower. Be extra careful if you have a riding mower and try to avoid this step if you can. Use a trowel to loosen up and get rid of any clumps of grass clippings that may be in the way.
To prevent this from happening again, you can do a quick clean of your mower every time you finish mowing so that you prevent build-up.
How To Make Sure Your Lawnmower Starts After Sitting
Proper Storage
If you know that your lawnmower isn’t going to be used for a while, such as over winter, you need to make sure that it is stored in a safe place that’s going to protect it from the elements. For winter storage, a garage or garden shed would be best. Any area that’s away from a furnace or water heater will be suitable.
Use Gas That Doesn’t Contain Ethanol
Ethanol has been known to damage small motor carburetors over time. While gas without ethanol is more expensive, it’s definitely worth the extra investment, as you’ll be saving on replacement parts and regular trips to a lawnmower mechanic.
Get Professional Lawn Maintenance
While there are many things we can DIY at home, some things are best left to the professionals. Taking care of the day-to-day maintenance of your lawnmower is great, but when it comes to annual servicing and major repairs, it’s better to hand it over to a professional lawnmower mechanic to sort it out for you.
You may be incurring a cost by engaging with a professional, but it’s definitely a worthwhile investment that’ll boost your lawnmower’s life span and keep you off the lawnmower market for a good couple of years.
FAQs
Why Is It So Hard To Start My Lawn Mower?
It is so hard to start your lawn mower because it could have a loose or dirty spark plug, a dirty air filter or fuel filter, or fuel may not be reaching the engine. You can clean the spark plug and air filter and tap the side of the carburetor.
Why Does It Take 10 Pulls To Start My Lawn Mower?
It takes 10 pulls to start your lawn mower because the fuel filter is filled with debris, the spark plug is faulty, the battery is damaged or it doesn’t have fuel to run. A faulty engine will take more pulls to start because it won’t combust the oxygen and fuel.
Can I Use Vegetable Oil In My Lawn Mower If I’m Low On Money?
You can use vegetable oil in your lawn mower if you’re low on money. However, this can only be done without any modifications if you have a diesel engine mower. Vegetable oil isn’t recommended for regular use because it can do more harm than good, such as damaging the engine.
Final Thoughts
Let’s face it: lawn mowers are expensive machines. If there’s a chance you can fix your existing mower and restore it back to working condition, you should definitely take it!
There’s nothing worse than wanting to get your yard ready for spring but your lawnmower just doesn’t want to cooperate. I hope my article has helped you figure out why your lawn mower may be acting up after sitting for a while and that these tips help you ensure that your mower runs smoothly!
Leave a comment below if you found this helpful! I’d love to hear from you.
Last update on 2023-05-28 at 05:39 / Affiliate links / Images from Amazon Product Advertising API