For your lawn mower to run smoothly, it is critical that it has good airflow through a fresh, clean filter. So do you need to replace your lawn mower air filter every time it gets clogged or can you just clean the filter off and put it back in? It all depends on how dirty the filter is.

Types of lawn mower air filters

The type of air filter your lawn mower has completely depends on your mower and the size of its engine. Small, walk-behind mowers often just have a thin paper filter that you need to check monthly at the minimum. Some walk-behinds actually have a small foam filter.

Some lawn tractors have a foam filter in a filter box, attached to their carburetor. Others have a larger airbox plumbed to the carburetor, containing a filter.

Larger mowers, or premium mowers may have a combination filter. This includes a large airbox with a paper filter and a foam pre-cleaner. This spongey pre-cleaner is wrapped around the paper filter to help it last longer.

How to clean a lawn mower air filter

If you have a paper filter you can’t do much more cleaning than trying to tap dirt and debris out of it. According to the Powered Outdoors website, you should never try to blow the dirt out of a paper filter with compressed air; you run a risk of damaging your filter beyond repair.

You can get more aggressive when cleaning a spongey foam filter or pre-cleaner. This is because you can wash the filter clean with warm water and soap. Afterward, make sure to let it dry completely, then apply some filter oil to it.

When do you need to replace a lawn mower air filter?

Simply put, a filter that no longer allows air to pass through easily needs to be replaced. If you have a paper lawn mower filter, hold it up to the light. If you can’t see any light you need to replace it. If your foam filter is soiled after washing or is ripped, you’ll need to replace that too.

According to the Tractor Supply Company, you simply must replace your lawn mower filter as part of your yearly maintenance. Some lawn mower owners prefer to do their yearly maintenance when they winterize their mowers in the fall, others when they get them back out in the spring. Whenever you do your yearly maintenance, it includes replacing your oil, fuel, and air filters. Luckily, you can often find a combination deal on these filters.

While you only need to replace your filter yearly, you do need to examine it more often. You should examine a larger lawn tractor air filter every 100 hours of mowing. But if you have a walk-behind mower with a tiny air filter, you need to examine it at least once a month.

It isn’t a bad idea to take a look at your air filter every time you go out to mow and check your oil and tire pressure. If its soiled, you can always try to clean it. But if its too dirty to clean, it’s time to replace it.

Want more info? read our detailed lawn mower service schedule or see how to clean a lawn mower air filter yourself in the video below: