How To Fix A Lawnmower That Will Not Start. Start the lawn mower
How To Fix A Lawnmower That Will Not Start
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The two basic requirements that allow a lawnmower’s engine to startup are fuel and a spark. If you are experiencing fuel starvations (when fuel is not getting to your engine), or if you are not getting a spark at the plug, your engine will not be able to startup.
Bad compression can also be a reason for experiencing difficulty while trying to start the lawnmower’s engine. If you pack the lawnmower away for the winter with fuel still in the tank, the seals, valves, and pumps in the lawnmower’s carburetor can become blocked up with varnish deposits. Along with this, dirt and dust can get collected and end up blocking the fuel system or clog filters.
Before You Start Troubleshooting On Your Mower You Should:
Proceed with caution when working with your mower. You should first start by removing any sources of ignition. This includes cigarettes, naked flames, sparks, stoves, or other hot objects that are in the same area that you intend on working on the tank or fuel lines.
Be sure to do this if you need to remove any clumps of grass that may be jammed under the deck.
This is to avoid the oils in the mower from spilling, as this is likely to happen if left on its side.
This can be avoided if there is a small amount of gas in the tank, or if you do not think that it will reach the tank cap. However, if you are unsure of this then it would be best to just drain the tank. Another trick is to open the cap and then place a plastic bag over the opening and then put the cap back on.
You are likely to cause premature engine wear if the oil level is low. Added to this, an engine can seize quickly if there is no oil present in the lawnmower.
Checking On The Oil Level Of Your Lawnmower:
Before starting the process of troubleshooting, you should make sure that the oil level in the lawnmower is deemed acceptable. You can do this by:
- Move the lawnmower to a surface that is level.
- Remove the dipstick and wipe it clean.
- Place it back in the lawnmower and then remove it again.
- Check to see where the marking is. If it is relatively low, top it up to the necessary level.
You should make a mental note that the oil in the tank should be changed after every 25 to 50 hours of run time or as advised in your engine manual.
Tips To How To Get Your Lawnmower Started:
How Do You Start A Lawnmower With Old Gas?
Although, it is recommended to drain the lawnmower’s gas tank before it sits for a long period of time without any use. However, most people do not do this. The result of not draining the gas tank causes residue build-up. If this occurs, you should refer to your lawnmower’s manual for information on how to remove this build-up from the fuel tank effectively, as well as for service procedures. Or see our guide on this problem.
As soon as the build-up has been cleaned out, gather all the old gasoline and put it in a container to dispose of it properly. This can be done by running a siphon hose from the gas tank to the container and then pumping the bulb a few times. In doing this, you are moving the gas from the fuel tank and draining it into the container, which thereby cleans out the lawnmower’s fuel tank.
If your lawnmower still is not working after you have cleaned out the fuel tank and adding new gasoline to the mower, you should make sure that your spark plug is working. There is a large possibility that the spark plug wire will become loose after being stored for long periods at a time.
A common problem found when trying to restart a lawnmower that has been stored in that the carburetor gets flooded. Be sure to note the smells and sounds of the lawnmower while you are trying to start it. A strong gasoline smell could mean that the carburetor has been flooded, and as a result, the lawnmower will not start. In this case, you should wait a few minutes before you try to start the mower again.
How Do You Dispose Of Your Lawnmower’s Oil?
When cleaning out the oil in your mower, be sure to collect in a bottle-like container that screws shut. This is to prevent any spilling. Your local mechanic or oil change shop should usually take your used motor oil to dispose of properly. However, if this is not possible, there may be disposal programs for motor oil at your local dump.
If smoke is coming out of your mower, this could be a sign that the oil needs to be checked and changed. However, a lawnmower that will not start obviously will not smoke. Nonetheless, this is a good sign to look out for as it will allow you to stay on top of your lawnmower maintenance. Added to this, smoke coming from a mower could show that there is a leak somewhere. The leak causes the oil to burn when it lands on hot surfaces such as hot metal. Along with this, smoke can also indicate that there is not enough oil in the lawnmower. Not enough oil has the potential to cause permanent damage to the engine of the mower.
What Are The Options For No-Hassle Gas?
One form of no-hassle gas is a product called TruFuel and it is available in most hardware stores. Known to be “old school” gasoline that has no added ethanol. What is so great about this product is that you do not have to add any fuel stabilizers. It runs clean and can sit in storage all winter and will still start up very easily.
However, it is more expensive than regular gas. Nonetheless, when you weigh in that while using no-hassle gas you will not need to pay to replace your lawnmower or carburetor every few years.
So after reading my post on how to start a lawnmower that won’t start and you decide that it’s easier just to buy a new one, then be sure to check out my post on the best mowers that are under 300.
Hi, Alex Kuritz here. Growing up I remember that my family had one of the best lawns in the neighborhood. Richly green and lush. I did a lot as I grew up in terms of caring and tending for not only my family’s lawn but also my neighbors. I can say I have years of experience, and I am here to share it with you.
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
Tips for Starting a Lawn Mower with Old Gas

When you think of things that get old and start to go bad, you tend to think about food products. One thing that probably does not come to mind is gasoline. But over time gas breaks down, and when left in machinery such as lawn mowers it can cause reduced performance or even difficulty starting. If you have old gas in your lawn mower, don’t fret. Here are some tips for starting a lawn mower with old gas that will get your mower out of the garage and purring like a kitten this Spring.
Clean out your lawn mowers gas tank.
While it is highly recommended that you drain the gas from your lawn mower before letting it sit for long periods of time, not many people don’t know this (which is probably why you’re reading this post).
When gas sits in your law mover it will break down and cause residue build-up. Refer to your lawn mower’s manual for service procedures and information on how to remove the build-up from the fuel tank.
And if you don’t want to face this problem again next Spring, read and follow my lawn mower winterization guide this coming fall.
Remove the Remaining Gas from the Tank.
Once the build-up is gone, siphon out the old gasoline and put it in a container for proper disposal.
After doing this, try starting your lawn mower again.
And while we’re on the subject of spark plugs – you should replace your mower’s spark plug every other year. It’s cheap (under 10), and just takes a few minutes.
Don’t Flood the Carburetor
A common mistake when trying to restart your lawn mower after not using it is flooding the carburetor.
When trying to start your lawn mower, be sure to note the sounds and smells it is creating. Stop trying to restart the mower when the smell of gas becomes strong.
A strong gas smell means a flooded carburetor.
Wait a few minutes before trying to start the mower again.
Starting a Lawn Mower with Old Gas is Easy with TruFuel
Because I’m the Lawn Chick and my mower deserves nothing but the best, I run a product called TruFuel in my mower.
It’s good old-fashioned gasoline that is ethanol-free.
This gas is more expensive, but I can leave it in my mower all winter and every spring my Honda starts right up on the first pull. I use it in my snow blower as well, and I’ve never had to have either machine professionally serviced. I highly recommend it. You can pick it up on Amazon, and most box stores and local hardware stores carry it as well.
Ensure Proper Maintenance Before Putting Your Mower Away
You can treat your gas to winterize it, or you can use the more expensive product I mentioned above, but the easiest way to ensure your lawn mower will start after a long winter is to simply drain the old gas out of the fuel tank before you put it away.
Clean the moving parts of your lawn mowers engine and make sure the spark plug wire is pushed in. Use a can of starting fluid as a last resort.
There is nothing more satisfying than bringing your lawn mower out of storage, having it start right up and deliver the sacred smell of fresh-cut grass.
Be prepared for that time of the year and take care of your lawn mower.
What to do If My Lawn Mower Won’t Start
After being in storage for the winter months, your lawn mower might not want to start at the first turn of the key. This is common, so don’t get too concerned right away. Continue reading to see what to do if your lawn mower isn’t starting for you.
Do you need lawn mower service right now? Get in touch with the team at Koenig Equipment to get the support you need and schedule an appointment with us today!

What’s the starting procedure for my lawn tractor?
The standard starting procedure for lawn tractors is rather simple and the same across most lawn mowers.
- Put the choke lever in the full choke position.
- Turn the key to crank the engine for about five seconds.
- If your engine hasn’t started from the above steps, let the engine rest for about 10 seconds and then crank the engine for another five seconds. If the engine sounds like it is about to start, you can crank it slightly for more than five seconds.
In addition to the above steps, if you have a riding lawn tractor, there is a seat sensor included for safety. If you are not sitting in the seat, the sensor will know, and the mower will not start. For push mowers, there is a safety handle.
Is the problem with the battery or with the starter?
If you are going through the proper starting procedure with your lawn tractor and it is not starting, it is time to check the battery and the starter. The best place to start with is the battery. Without enough electricity, an engine starter problem can’t be diagnosed. Check to ensure that all the connections are properly hooked up to the battery. If the lawn tractor still won’t start, you can try jump-starting it. Jump-starting your lawn tractor will rule out a weak battery. You can also utilize a voltmeter to test your battery health and strength.
After confirming your battery is not the problem, you can look towards the starter. An easy sign to see if the starter is your problem is if it makes a clicking sound when you are trying to start the lawn tractor by turning the key. If this is the case, we may recommend replacing the starter, but it will take a service appointment to correctly diagnose the issue.
Is there a difference between starting in cold weather and warm weather?
The starting procedure discussed above is the same for starting a lawn tractor in either cold or warm weather. If you are using your lawn tractor for tasks during cold winter months, make sure you are using the proper oil for the temperature. Some oils aren’t made for lower temperatures and can become thicker in the winter months, causing your equipment to not start properly. Your local technician or parts specialist can help you choose the right oil for winter weather.
Is it common to have starting problems after storage?
Starting problems with your lawn tractor can be rather common after storage. Before you put your equipment away for winter storage, be sure you are winterizing your lawn tractor properly to help reduce any starting problems in the spring. Ensuring you winterize your lawn tractor before storage will make it much easier to start up when you bring it out again.
Where can I find lawn tractor service near me?
When it comes time to mow again, you want your lawn tractor to work properly and start easily for the upcoming season. If you get your lawn tractor out and have issues starting it, even after following the standard starting procedure and checking the battery and spark plugs, the certified team at Koenig Equipment is here to help.
With the certified service department at each Koenig Equipment location, you can rest assured knowing they will solve any issues that may arise with your lawn tractor.