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It’s tempting to fire up your lawn mower once a week, mow your lawn, and put it away again without a second thought. But a well-maintained lawnmower will last longer and may result in a healthier lawn. Here is what service your lawnmower needs and how often. Note: if you don’t do anything else today, bookmark this article and begin to record how many hours you are running your mower a week.

Beginning of the season lawn mower service

A walk-behind mower parked on a fresh lawn.
Walk-behind lawn mower | Andres Simon via Unsplash

Before firing up your lawnmower do its first service: make sure it has enough oil and its tires are properly inflated. Also, drain any old gas and pour fresh, unleaded gasoline into the tank. The beginning of the season is also a great time to check that your lawn mower’s blades are sharp and–if it’s a lawn tractor–that its deck blade is tight.

Once a season, you also want to replace your mower’s spark plug, change its air filter, and swap its in-line fuel filter if it has one. In-line fuel filters are a great thing to add to a lawn mower’s fuel line if it does not come with one.

The Tractor Supply Company has an interesting suggestion for your first lawnmower oil change: run your mower for about five hours at the beginning of the season without changing the oil. During this first run, this oil will become especially fouled with any contaminants that floated into the engine during storage.

After this initial run, swap your oil and your filter. After changing your oil, run the mower for a few minutes and measure the oil level to make certain the mower is full. Here’s how to change the oil in your lawnmower.

Lawnmower service every 25 hours of use

A black lawn tractor/mower parked behind a red garage during its maintenance service.
Lawn tractor | Erik McLean via Unsplash

If you use your mower more, you need to maintain it more often. Keep track of how many hours you are running your lawnmower. After 25 hours of lawn mowing, it is important to look over our mower.

Does your walk-behind lawnmower have a lightweight paper air cleaner? Does it have a foam air cleaner or pre-cleaner? If it has either of these (and not a heavy-duty dual-element filter found in a lawn tractor or ride-on lawnmower) you should swap it after 25 hours of mowing.

In addition, The Home Depot recommends you sharpen your mower blades every time you hit a rock, or after every 25 hours of mowing. Check out how to sharpen your lawnmower blades.

Lawnmower service every 50 hours of use

Orange ride-on lawn mower parked on a hill overlooking a town.
Ride-on lawn mower | Elias Null via Unsplash

Did you run your lawnmower for 50 hours this season? This would equal five hours of use once per week for 10 weeks. If so, you will need to repeat all the 25-hour service/maintenance items: sharpen your blades and change any lightweight air cleaners.

In addition, the Tractor Supply Company (TSC) recommends you also change your engine oil after 50 hours of lawn mowing.

TSC also recommends you change your engine oil filter every season but adds that you can get away with swapping filters every other oil change if you change oil twice a season. So if you expect to run your mower for 100 hours this summer, and change the oil twice, you only need to swap its filter once.

Lawnmower service every 100 hours of use

Birds-eye view of a green John Deer ride-on lawn mower in a field.
John Deere lawn mower | Adlan via Unsplash

If you’re a professional landscaper, using your lawnmower daily, you will likely have to do its 100-hour service items during the season. At 100 hours of runtime, you want to swap the oil again, changing the filter this time.

During this lawn more maintenance, you also want to swap out any air filters. Then, replace the in-line fuel filter if your mower has one. At 100 hours, definitely also give your blades another sharpen and double-check that deck belt tightness.

End-of-season lawn mower maintenance

Closeup of freshly mowed grass.
Mowed lawn | Petar Tonchev via Unsplash

It’s important that you pour some fuel stabilizer into your lawn mower’s gas tank and run it for a few minutes before storing it for the season. Without a stabilizer agent, the fuel in its gas tank and carburetor will go stale during the winter. TSC does not recommend draining the gasoline out of your carburetor, but some lawn mower owners do this anyway.

TSC does recommend storing your lawnmower with fresh oil in the engine, so do one more oil change before putting it away. If you have yet to change the air filter, spark plug, or fuel filter you will want to swap these–or note to replace them first thing in the spring.

Finally, wash any excess dirt and old grass off your mower: you don’t want it to attract pests during the fall or spring. Then store it in a clean, dry place such as a shed or garage.

Next, see how to service or change your lawn mower spark plug or learn how to service your lawn mower in the video below:


Bob Vila’s Best Oils for Lawn Mower Maintenance