It’s important to replace your lawn mower air filter during your yearly maintenance. But some mowers, in some conditions, will require filter replacement more often. Here’s how to find, examine, and replace your lawn mower air filter.

Where is your lawn mower’s air filter?

The location of your lawn mower’s air filter will depend on what type of mower you have. But remember, that air enters your engine through your carberator, so your air filter will almost always be on the carb side of your engine.

On a small, walk-behind lawn mower your air filter may be a small piece of paper, on your carb and under your engine cover. Larger mowers may have a larger foam or air filter under a cover, on top of your carburetor. Still other mowers have a large air box plumbed to the carburetor with a filter inside.

If you can’t find your filter location in your lawn mower’s owner’s manual, find the carburetor feeding gasoline to your engine, and look for your air filter nearby.

How do you access your lawn mower’s air filter?

Many lawn mower air filters are located in a plastic airbox. You will need to remove the cover of this airbox to access your filter. On lawn tractors, this airbox is under the tractor’s hood. On riding mowers, it will often be under the engine cover.

Again, consult your owner’s manual to learn the process for removing your air filter. If you can’t find it, then locate the air filter cover/box.

Because these boxes are not pressurized and don’t need to contain liquid, they are not screwed together incredibly tightly. For this reason, many air boxes are held together with big thumb screws you can remove by hand. Some have metal spring clips holding the air box together.

Simply remove the air filter cover or the top of the air filter box and you can access your lawn mower’s air filter.

How do you examine your lawn mower’s air filter?

Different lawn mowers have different types of filters. Inspecting a simple air filter is easy: hold it up to the light and see if any light shines through. If not, you need a new one. On a foam filter, look for tears and excessive dirt. You can wash a foam filter and check again.

When examining your air filter, ask yourself if air could easily pass through it–according to the Powered Outdoors website. A paper filter so soiled that light can’t get through will not allow your engine to breathe very easily. The same can be said of a sponge filter.

Remember that many lawn mowers have a paper filter filament inside of a spongey foam pre-cleaner. The great thing about this setup is that you may be able to clean this pre-filter with soap and water and it will keep your paper filter lasting longer.

Next, see our complete guide to your lawn mower service schedule or see how to replace a lawn mower air filter yourself in the video below: