How To Winterize A Lawn Mower

How To Winterize A Lawn Mower


December 29, 2021

Similar to how parents give their kids nice treats when they do something impressive, your lawnmower deserves special treatment too!

This is particularly the case at the end of every lawn-mowing season.

How do you winterize a lawn mower? But winterizing isn’t merely about cleaning your mower and storing it for the off-season. The process involves replacing the spark plugs, oil, air filters, and cleaning the mower. 

While it can be tempting to just store away your mower until next season, putting off this simple yet important activity will only make things worse.

You will likely run into issues getting the mower up and running when the next lawn-trimming season arrives and you start lawn mowing.

Read on to learn how to winterize a lawnmower before storing it for winter.

Why Should You Winterize Your Lawn Mower?

How To Winterize A Lawn Mower

During the warm season, it is common to use gas-powered lawnmowers and trimmers quite excessively.

This is normal for most homes with a lawn.

Even if you don’t know the first thing about proper mower maintenance and storage, you probably know that storing metal for a long time with dirt and debris will encourage rust and corrosion.

But winterizing isn’t merely about cleaning your mower and storing it for the off-season.

You want your lawnmower to stir up at the first pull of the cord come next spring, right? That means you must winterize it at the end of the season.

Leaving gas and oil in the tank while your mower is in storage, is a recipe for plenty of headaches.

You need to learn how to winterize a lawnmower if the parts must continue to work in perfect condition, even after being in storage for a long time.

The process involves replacing the spark plugs, oil, air filters, and cleaning the mower.  Here’s another perspective you should consider.

Winterizing your mower isn’t just about mower maintenance. Instead, it is actually part of lawn care. And here’s what that means.

Lawns need TLC to remain gorgeous and healthy. Everyone knows that trimming and cutting grasses aren’t tasks that can be done effectively using bare hands.

What better way is there to care for your lawn than looking after the one tool that can cut and trim your grass efficiently?

How to Winterize a Lawn Mower in 8 Simple Steps

Now that we’ve seen the importance of preparing your mower for the cold season, let’s delve into the exact steps to winterize a lawnmower for an end-of-summer tune-up and proper storage.

Things You’ll Need

Winterizing your mower is pretty straightforward and just about anyone can do it since it doesn’t require any special skills.

However, you still need the right tools and items to do a proper job. These include:

  • Empty can (for storing the drained gas)
  • Hand gloves
  • A correct-size wrench or hollow nut driver
  • A pan (for collecting oil during draining)
  • Tarp (for catching oil spills)
  • Wire brush and putty knife  
  • Garden hose, soapy water, and a soft brush
  • Air filter (optional)

Keep in mind that while this maintenance task is easy, it can get messy. Thankfully, you can get it over within about an hour or so.

Step 1: Empty the Gas Tank

How To Winterize A Lawn Mower

Emptying the gas tank is the single most important step if you want your mower to start come next spring.

When gas is left in a mower unused over the winter, it will most likely get stale. But that’s pale in comparison to gumming up the carburetor and causing rust.

To empty the gas or fuel, don’t just dump it onto your grass or somewhere in your yard. Instead, here’s what you should do:

  • Start by adding a fuel stabilizer to the tank.
  • Next, run mower to distribute the stabilized fuel all through the system.
  • Now, turn off the mower and give the engine some time to cool down.
  • Drain the gas into a clean container where you plan to store the fuel. If you don’t plan to store the gas, you can use it in your car. But be sure the gas isn’t all mixed with oil so it won’t cause problems for your vehicle.
  • Lastly, run the mower until it stops on its own. Turn it back on and run the mower until the fuel line is completely empty and the engine no longer starts.

Note: If you have an electric mower, make sure to remove the batteries. Store them in place inside your home with little to no temperature fluctuation.

Your batteries can fail prematurely when stored in extreme temperatures.

Although most batteries can be stored in areas with temperatures of 40oF and 80oF, it is usually best to follow the manufacturer’s instructions in the owner’s manual.

Step 2: Disconnect the Spark Plugs

Next, disconnect the spark plugs. This step is crucial and you shouldn’t proceed with the rest of the maintenance without doing it.

Leaving the spark plugs intact while you work on the mower can accidentally kick-start the machine. This can be disastrous and even lead to very serious injury.

To prevent this from ever happening, it is best to disconnect the spark plugs.

Step 3: Remove the Blade

How To Winterize A Lawn Mower

Detach the blade by unscrewing the bolts using a wrench or hollow nut driver. This will make it easier to perform other maintenance tasks such as cleaning under the mower and changing the oil.

Remember to wear thick gloves before attempting to remove the blade.

Inspect the blade once it comes off to see if it requires sharpening. Be sure to sharpen it if necessary before storage.

Step 4: Drain the Oil

You may skip this step if your mower has a 2-cycle engine. That’s because the oil is typically mixed with the gas in this type of engine. So, you’ve already drained the oil in step 1 above.

If you have a 4-cycle engine, you will need to drain the oil separately.

Here’s how to do this:

  • Place a tarp beneath the mower to oil spills.
  • Put a pan beside the mower where you will drain the oil
  • With the mower on its side, the air filter and carburetor should be facing up. This will prevent oil and any gas residue from spilling into them.
  • Next, remove the oil reservoir plug and gently tilt the mower. The oil should drain into the pan.
  • Replace the plug once the oil is completely drained.

Step 5: Clean the Undercarriage (Underside of the Mower)

How To Winterize A Lawn Mower

With the gas and oil tanks empty, it’s time to clean the underside of your mower. Cleaning the undercarriage will help prevent rust and allow the deck to function optimally.

There are a couple of ways you can do this, depending on the tools you have.

Here’s one of the easiest ways:

  • Turn the mower so you can access the underside.
  • Remove any caked-up mud, grass, dirt, and debris using a wire brush and putty knife.
  • Next, use a garden hose to spray the underside to loosen any dried-on dirt.
  • Use a soft brush and soapy water to scrub the underside until clean.
  • Rinse off thoroughly and allow it to dry.
  • Reattach the blades after cleaning the deck.

Once you’re done cleaning the undercarriage, turn the mower upright and fill the oil tank with lightweight oil (avoid thicker oil).

Go ahead and recycle the drained oil at a service station.

Step 6: Change the Air Filter

A clean air filter means your mower’s engine will limit the air required for combustion. This means it will burn gas more effectively.

Before storing your mower for the winter, it is a good practice to replace the air filter, especially if you have a paper filter.

For a foam filter, remove and wash it with soap and water. Let it dry completely before applying some oil.  

Next, put the air filter back in the mower.

For more details about cleaning and changing air filters, read this guide on How To Clean Lawn Mower Air Filter.

Step 7: Replace the Spark Plug

Step 7: Replace the Spark Plug

The spark plug should be removed and replaced using a wrench with a spark-plug socket.

Your old spark plug might still be working alright, but a new spark plug goes for only a few dollars.

Consider getting a new one to ensure smooth performance in the next mowing season.

Step 8: Safely Put Away any Combustible

Use an appropriate container to store your gasoline. Do not put gasoline in your home, especially near any heat source.

Instead, store the gasoline in a shed or detached garage. It should be kept 50 feet or more from any ignition source.

To help keep the gasoline fresh, consider adding a fuel stabilizer. This can keep the gasoline in good condition for up to two years.

If you have batteries in your mower, they may lose their charge in extremely cold weather. Plus, there is a chance that they can catch fire.

We strongly recommend removing any batteries from your mower and any other lawn equipment for long-term storage.


Winterizing your mower at the end of the season is essential to keep your machine working as it should come next season.

These maintenance steps might seem overwhelming at first blush, but in reality, the process is pretty straightforward.



Rebecca Vargas is an experienced gardener and landscaper and has been rendering professional services for many years. Her services cover both private homes and commercial properties. Leveraging that rich experience, Rebecca Vargas now dedicates a chunk of time to show just about anyone how to maintain their garden and yard, whether at home or workplace. GreenIQ is his way of reaching and teaching millions of homeowners across the globe about proper gardening and lawn care practices.