How to Winterize a Lawn Mower

Lawn mower
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Preparing your mower for winter will extend its engine life and improve performance. When the lawn chores are done for the season, the mower will not likely be in use until the spring so store it out of the way. Ensure the storage area is cool and dry and cover the mower to keep it clean and protected.

Before it gets covered up, though, be sure these basic, simple steps from Consumer Reports are followed to ensure proper winterization.

Stabilize the Fuel

Gas that sits in a mower all winter can clog the carburetor. Come spring, you’ll have to pay upwards of $100 to have the part professionally cleaned.

If you store the mower in the basement, run the engine until the gas is gone. If you keep it in the garage, fill the tank (to prevent condensation) and add a bit of fuel stabilizer, available at home centers and gas stations.

Add stabilizer every time you fill up your gas container since it helps engines run cleaner. This time around, remember to operate the mower for 5 minutes so that the stabilizer can reach the carburetor. 

Change the Oil

Routine oil changes will extend the life of the engine. Be sure to refill the oil reservoir to the designated mark on the dipstick, remembering that too much oil can be as bad for the engine as too little. 

Charge the Battery

If your mower or tractor has a battery-powered starter system, periodically charge the battery throughout the winter.

Otherwise, it will fail much sooner because it will not hold a full charge. Unlike your car, mower engines can not fully recharge your battery while mowing.

Clear the Deck

Scrape grass clippings from the underside of the mower deck to prevent it from rusting. If you do this right after the final mow, spray from a garden hose should be enough to clear the clippings.

Otherwise, an old bristled pot scrubber is an effective tool. 

Possibly Replace the Spark Plug(s)

Spark plugs typically need replacing every 100 hours of operation. You’ll know right away from the corrosion if yours is spent. If the plug is in good shape, it’s a good idea to remove it, pour an ounce of motor oil into the cylinders, crank the engine a few times, and then reinstall the plug.

Think About Sharpening the Blades 

Save yourself the hassle next spring by getting your blades sharpened now. Keep a second blade on hand for when the first one is being sharpened. Change blades every month during the mowing season to keep dull blades from butchering grass.

Do You Need to Service the Air Filter?

Refer to the owner’s manual to see if you should clean or replace the filter and how frequently.

Do You Need to Replace the Fuel Filter?

Refer to the owner’s manual for specific instructions. Mowers usually don’t have a fuel filter, though many lawn tractors do.