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.
Lawnmower Only Starts With Starting Fluid! Step By Step Repair!
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
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.
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.
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.
About The Author
Brett’s the kind of guy you’d never peg as having such an amazing yard. He’s shy and private, avoiding social media and the spotlight. By day, Brett works quietly as an electrician technician, helping folks with wiring and repairs. But get Brett home to his place in Raleigh, where Nadya’s always dreaming up new landscaping ideas, and you see another side of him. Brett happily rolls up his sleeves to transform their modest backyard into a lush, cozy oasis. The yard’s really a labor of love for them, a place to unwind on weekends, entertain friends, and make cherished memories together. Nadya might come up with all the creative concepts, but Brett’s the one ensuring each vision comes to stunning life. They make a great team, even if Brett’s content to operate behind the scenes. At heart, Brett’s a simple man who finds purpose and joy in small things. Puttering in their garden under the sun or cooking out back in the evenings. these are the things that fulfill him. Brett cares deeply for crafting a space ideal for intimacy, nurturing a life well-lived away from fanfare. Follow him on
Last update on 2023-07-21 at 02:14 / Affiliate links / Images from Amazon Product Advertising API
Solutions For Rough Running Non-Starting Lawn Mowers
You bought a lawn mower to maintain a well-kept yard. So it’s frustrating when the engine runs rough or doesn’t start at all, leaving you helpless as the grass is given that much more time to grow. It almost feels like your lawn and mower made a secret pact behind your back, and this is their way of mocking you.
Take back control of your yard by troubleshooting the three most common reasons your lawn mower runs rough or simply won’t start. After all, you are the master and commander of your domain. Not your outdoor power equipment.
Fixing Fuel-Related Issues
Dormant lawn mowers that haven’t seen action over the winter are notorious for starting issues, and there’s a good reason for that.
When old gasoline sits idly in the tank, it can gum up and restrict the carburetor. This piece of equipment must remain clear of debris in order to mix air and fuel to create the combustion necessary for the engine to turn over.
There are two ways to troubleshoot a restricted lawn mower carb. First, use a small engine treatment to clean out the entire fuel system and crankcase. This will clear debris away from the carburetor jet, float bowls, and other fuel system components and allow the lawn mower to start. All you need is one ounce of product per gallon of gas.
The second is a preventive measure to set you up for success the next time you take out your lawn mower. Fill up the tank with fresh gasoline with “fresh” being the key term here. Once added, top it off with a fuel stabilizer to maintain its quality so it won’t harm the engine’s internal components.
Addressing Spark Plug Problems
Bad gasoline does not only cause potential issues with the carburetor. It can also lead to carbon buildup on the spark plug. In this scenario, it’s likely the piece is in need of replacing, but there are steps you can take to maintain the overall integrity of your lawn mower moving forward.
Start using an additive that will keep the mower’s fuel system clean and operating properly throughout the season. The right multi-system additive can even be used in the oil to lubricate the engine and help it run more smoothly if it has been making a lot of noise.
What To Do When Your Lawn Mower Won’t Start
Let’s say you push the mower handle firmly, draw the starter cord back, and it’s clear that the engine will not start. In this case, you require an innovative fuel system cleaner that doubles as a starting fluid.
Since the fuel system cleaner liquid is more dense than gasoline, it gets sucked into the engine once you try starting your engine back up. You can almost think of it the same way plumbers use Drano for pipes.
Add this product directly into the fuel reserve of your push mower the next time it gives you trouble starting. It will ensure a quick and easy start by removing the gum and varnish that restricts air and fuel flow.
Fixing rough-running engines or ones that won’t start is quicker and more cost-efficient than replacing it altogether. If you are ever in a bind, consult the helpful infographic below to better understand what you need for each scenario.
It’s a deflating feeling when you find time to cut the grass, but your equipment prevents you from making it happen. But rest assured. If you learn one thing from this article, know that you can troubleshoot a rough-running lawn mower more often than not.
So keep these tips in mind the next time you pull the starter cord, and all you hear are clicks. You now know how to diagnose the problem and when the engine turns over, think of us and this amusing moment from the 1998 comedy, The Waterboy.
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.
How To Troubleshoot a Lawn Mower That Isn’t Turning Over
Have you ever encountered a situation where your lawn mower won’t turn over or fails to do that even after several tries? If yes, it must have kept you thinking about whether it is possible to troubleshoot this problem or how to troubleshoot a lawn mower that doesn’t turn over.
Firstly, gather up all the required tools and materials. Then, inspect the current state of the spark plugs, spark plug lead, battery, solenoid, and starter thoroughly. Clean, repair or replace the faulty or damaged internal elements. Next, check whether the engine is seized up and manually push the blades to unseize it.
Keep reading this following article and learn the detailed way of troubleshooting a lawn mower not turning over.
Steps to troubleshoot a lawn mower not turning over:
Imagine you are about to start your work, and out of the blue, you figure out that your lawn mower not turning over.
If you have no recollection of what might have gone wrong or cannot pinpoint the reason behind such commotion, you can start by checking the basic areas and applying simple fixing tricks.
Sometimes, people only think of bigger issues and overlook the simple minor faults that can lead us to experience such troubles.
But if minor fixes can save your time and money, why would you want to invest in professional servicing for minor fixings.
How to fix your lawnmower in 10 MINUTES with a 13 part!!
That’s why I have decided to present a quick, easy, and cost-effective DIY method of troubleshooting a lawn mower that does not turn over.
Things required to troubleshoot the lawn mower not turning over:
Have a proper glance at the checklist of the required tools and materials:
|Standard Mechanical toolkit||Spark plug cleaner|
|Socket||New Spark plug lead (if needed)|
|Spark plug tester||New Battery (if required)|
|Wire brush||New Starter kit (if necessary)|
|Safety Gloves||Solenoid replacement kit (if needed)|
Step 1- Check the Spark plugs Spark plug lead:
As soon as you encounter such troubles, you should make sure that the spark plugs and the plug lead are in good working condition.
First, you should check whether the spark plugs are operating properly or defected because the mower won’t turn over with a defective spark plug on it.
To inspect, disconnect the lead and clean the surrounding area. Then, use a socket to remove the plug.
Next, if the plug looks dirty, clean it with a wire brush and a spark plug cleaner. Then reinsert it again and ensure it fits into the position securely.
If the spark plug looks damaged, cracked, or broken, you should replace it.
After that, you should inspect the spark plug lead with a spark plug tester or multimeter.
Connect one tester prong to the spark plug lead and the other end to the spark plug. Then, try to start the engine and verify the result with your mower’s user manual. If required, replace the spark plug lead.
Step 2- Check the Battery, Solenoid Starter:
While checking the spark plugs and plug lead’s state, do not forget to inspect the condition of the battery and solenoid.
Follow the step-by-step instruction provided in this video to troubleshoot your mower battery thoroughly.
Watch this DIY video to test the solenoid’s condition.
Besides that, you should also test the starter to confirm whether the starter is the main culprit of your lawn mower’s turnover failure or not.
To troubleshoot your lawn mower starter easily and thoroughly, without skipping a single step follow this video.
Step 3- Manually pushing the Engine Blades:
In case you are experiencing the same issue of hearing only clicks whenever you turn the key, it’s most probably the engine is causing such trouble by being seized up.
Thus, manually just push on it to get the engine to turn over, but do not push it too hard because it’s plastic.
First, take this cover off and you will see four screws here.
Then, take off those screws too.
Now, try to push it with your fingers to make sure the motors are free and bound up.
Check whether the mower is starting over or turning over now and if none of the above fixing tricks work for your mower, be sure to contact the nearest service provider for professional assistance.
Performing such repairing tasks can be hazardous. Thus, make sure you have enough knowledge and expertise to perform them. Remember to first read your mower’s instructions manual before operating, servicing, or troubleshooting it.
Frequently Asked Questions
What causes my riding lawn mower not to crank?
There can be various reasons behind a riding lawn mower starting trouble or failure, such as stale gas, ignition switch malfunctioning, a bad battery, or failed alternator.
How to determine if my lawn mower spark plug is bad?
Remember, the more worn out or dirty the spark plugs are, the greater the tug on the rewind, and you will need more effort to produce an adequate spark.
Thus, if you notice that your lawn mower won’t start or the lawn mower engine requires a constant tug on the rewind to start, you most probably have a damaged or broken spark plug in your lawn mower ignition system.
Is it possible to unseize a lawn mower engine?
The easiest way to unseize your lawn mower engine is to turn the internal blades manually using your hand.
To do this, put on the safety gloves and hold or clamp down the blade activation lever on the handle. Then, try to push the blades.
Where should I spray starter fluid in my riding mower?
Spray a light quantity of starter fluid directly into your lawn mower’s carburetor chamber.
You can also spray the starter fluid into the intake near the air filter or the engine’s spark plug bore.
How to determine if the starter solenoid on my riding mower is bad?
The most common sign or symptoms of a bad starter solenoid are engine starting struggle, no cracking, no clicking sound while the engine starts, the starter tends to spin without engaging the Flywheel fully, or the engine cranks slowly.
Lawn mowers won’t turn over trouble is not a new thing among the mower user community, and sometimes, easy DIY fixing techniques can save both your time and money.
Initially, the entire troubleshooting process might seem a bit complicated, but if you follow all the instructions given in today’s article, you can fix the problem easily and quickly.
Remember, you can only get the best outcome if you thoroughly follow all the instructions to troubleshoot a lawn mower not turning over.
My Lawnmower Won’t Start — Troubleshooting Guide
Don’t freak out if your lawnmower won’t start. And certainly don’t buy a new one before you know exactly what’s wrong. There might be something very simple going on — something that you can fix on your own.
We’ve put together a brief troubleshooting guide for lawnmowers that won’t start. Whether you use a traditional hand-pushed mower or a riding model, work through the list before even thinking about a replacement.
My Lawnmower Won’t Start After Winter
If you use a fuel-powered lawnmower, you may have trouble getting it started after a long and cold winter. The problem may be related to the spark plug. Or a blockage in the fuel line may be starving the engine of gasoline. If you run into problems getting your lawnmower ready for spring, try the following:
- Use fresh gas. Old gasoline can cause starting difficulties. Also, make sure there’s enough gas in the tank, and that the vent in the tank isn’t blocked.
- Check the spark plug. Make sure the spark lead is properly attached to the plug. If there’s noticeable damage or corrosion, replace the entire spark plug.
- Use the choke. If your lawnmower has a manual choke, turn it one.
- Prime the mower. If there’s a primer bulb, press it a few times. You’ll also need to prime your lawnmower if it ran out of fuel while running.
- Check the air filter. A dirty air filter can interfere with the combustion process. Clean or replace the filter to ensure air passes through the engine unhindered.
- Check the cables. Check all the cables for damage. Pay particular attention to the cable that connects the “dead man’s handle” to the engine.
- Check for water in the fuel tank.
- Clear the starter cord of blockages. If you have difficulty pulling the starter cord, check for blockages caused by soil, grass, and vegetation. Make sure you disconnect the spark lead before doing this.
- Check the carburetor. It should be clear of blockages and gummy accumulations. It should also be firmly bolted to the engine.
My Lawnmower Won’t Start After Running
If you lose power when you’re mowing the lawn, the effects of a long, cold winter may have caused issues with pumps, seals, and valves in the carburetor. These components in and around the engine can become clogged with a range of substances — starving the engine of either fuel or air.
If you’ve tried all the troubleshooting tips listed above, first try to raise the cutting height of your lawnmower. If that doesn’t work, check for a build-up of vegetation and damaged blades.
Old, degraded oil can lead to the seizure of your lawnmower’s engine unless you replace it as quickly as possible. Drain the old oil fully before adding the new. Ideally, this should be done once a year — just before the first lawnmowing job if the year.
My Lawnmower Starts Then Dies
Again, go through the steps listed above if your lawnmower starts then dies within seconds. This could be down to old fuel left in the tank over the winter. If you suspect this to be the case, don’t — under any circumstances, drain the fuel tank. Doing so can draw air into the engine, causing accumulations of gum and varnish. There’s also a chance that water may be drawn in at the same time, causing widespread damage.
Before you do anything else, try adding STA-BIL Fuel Stabilizer to your lawnmower’s fuel tank. This specially-formulated fuel additive stops gasoline from breaking down into its component parts. Run the engine for a few minutes before trying again. If degraded fuel is to blame, there’s a good chance the stabilizer will do the trick.
For the best results, add some fuel stabilizer to every fuel can — particularly during the final weeks of fall