How to Clean and Change a Lawn Mower Air Filter in 9 Steps

The air filter in a gas lawn mower protects the engine from debris and dirt. A clean, fresh air filter promotes efficient airflow, improving combustion and overall performance. On the other hand, a clogged or dirty air filter can impede the engine’s efficiency, leading to reduced power, increased fuel consumption, and even engine damage. This guide walks you step-by-step through how to clean and change a lawn mower air filter to improve your mower’s performance and prolong the engine’s lifespan. 

How to Clean and Change a Lawn Mower Air Filter: Step-by-Step Guide

Prepare to give your mower’s air filter some much-needed attention. We’ve got you covered with instructions for a cleanup and a complete air filter replacement.

Step 1: Gather the Necessary Tools 

Tools you might require to work on your mower’s air filter include:

• Screwdriver: Depending on the design of your mower, you may need a screwdriver to remove screws or clips that secure the air filter housing.
• Compressed Air: An excellent tool for removing loose debris and grime from the air filter. You can use a can of compressed air or an air compressor.
• Clean Cloth: A soft cloth or paper towel can gently wipe down the housing and surrounding areas while performing maintenance.
• Replacement Air Filter: You might require a replacement air filter on hand if you intend to change the air filter. Check that it is the correct filter for your mower’s make and model.
• Gentle Soap: If your air filter is reusable and has to be deep-cleaned, a mild soap or liquid detergent might assist in cleaning the filter element. 
• Owner’s Manual: This isn’t technically a tool, yet it’s priceless. The owner’s manual for your mower contains detailed instructions and suggestions for maintaining the air filter, as well as other important information about the upkeep of your mower.

Step 2: Turn Off the Mower and Disconnect the Spark Plug

Safety is your co-pilot. To avoid any unexpected engine shenanigans, turn off the engine and disconnect the spark plug wire before you do anything else.

Step 3: Search for the Air Filter Housing

Consult your mower’s owner’s manual to find the location of the air filter housing. It’s generally near the top of the engine or carburetor. 

Screws or clips often secure the shroud, which you’ll have to remove to get to the air filter. Gently undo these fasteners using the appropriate tools, then carefully lift off the cover to expose the air filter underneath. Be mindful not to damage any components while removing the shroud.

Step 4: Take Out the Filter

Open the housing and carefully remove the filter, taking care not to damage it.

Step 5: Identify and Inspect the Filter

Examine the filter thoroughly before moving forward because there are three different types of air filters, each requiring different attention. The three types of mower air filters are: 

• Foam Air Filters: Foam air filters are the tried-and-true air filter warriors. They’re made of foam, which catches dirt and debris and keeps it out of the lawn mower’s carburetor. These filters are well-known for their longevity, low cost, and low maintenance. 

Examine foam air filters for indications of deterioration, such as crumbling or noticeable brown or yellow discoloration. These signs suggest the necessity of a replacement. However, if you do not find any of the above signs, you can proceed with the basic cleaning process.

• Paper Air Filters: Paper filters have numerous layers of thin paper that collect even the smallest particles. While they require more frequent replacement than foam filters, they are excellent at providing accurate filtration, ensuring your engine receives the cleanest air possible.

You can examine the paper filter by holding it up against the light. If the light doesn’t pass through the filter due to blockage from dirt and other small particles, it’s time to get a new filter. 

• Dual-Element/Hybrid Air Filters: Dual-element filters, aka hybrid filters, combine the durability of foam with the finer filtration of paper. For these filters, you need to examine the foam pre-cleaners regularly. If they are stiff or stained, then you need to replace the filter. 

If you determine your mower’s air filter just needs a cleaning and doesn’t need to be replaced, see step 6 below. But if you observe the indicators that it’s time to replace your filter, jump to step 7.

Step 6: Clean the Air Filter

To clean a paper filter, tap the filter lightly to remove any loose dirt. If you have compressed air, give the filter a light burst to dust off hard-packed debris. You can also combine mild liquid soap and water to remove stubborn dirt particles from the lawn mower air filter. Wash the filter gently, as if it were a fragile flower – intense cleaning can damage the paper folds. 

For a foam or hybrid filter, clean it using a gentle detergent with hot water. Then rinse it thoroughly with water and properly dry out the filter by squeezing it or using a paper towel or a clean cloth. You can lubricate the foam filter by massaging engine oil into it. Rinse the excess motor oil by pressing the filter against a clean cloth.

Pro Tip: Allow the filter to dry thoroughly before reattaching it to the mower. Wet filters and engines are not a good match.

Step 7: Replace the Air Filter if Needed

If the air filter is worn out, stained, or damaged in any way so that it can’t perform well even after cleaning, replace it with a new one. You can find a new air filter online or at most hardware stores. Consult your mower’s manufacturer’s manual to find the right size and model of air filter for your engine. 

Step 8: Reinstall the Clean/New Filter

Before you fit a clean or new air filter in place, clean the filter’s housing with a cloth to get rid of debris, dirt, and dust particles. Then, slide the filter into the holder carefully, ensuring it’s sitting correctly, with no gaps. With a pleasant click, close the housing and filter cover. If screws or clips were used to secure the housing, put them back in place. 

Step 9: Reconnect the Spark Plug Wire

Reconnect the spark plug wire and start your mower’s engine. Let it run for a few minutes and watch out for odd sounds or vibrations. If everything seems normal, your mower is ready to go!

Pro Tip: If you find any issue with the spark plug or the wire while starting the engine, consult our guide on How to Change Spark Plugs on a Lawn Mower to keep the engine running smoothly. 

When to Clean and Change the Air Filter

Clean the air filter in your lawn mower every 25 hours of operation. This will keep the air filter in good condition with no replacement needed for an extended period. As a general rule, you should replace the filter once a season or every 300 hours of use. 

Additionally, if your mower notifies you with any of the following signs, it might need air filter maintenance:  

• Decrease in mower’s cutting power
• Increased fuel consumption
• Difficulty in starting the engine
• Black smoke
• Engine overheating
• Visible dirt accumulation on the air filter

Note: Every mower is different; therefore, the owner’s manual is your best friend. It is the key to your mower’s heart, containing specific recommendations on when to clean or replace the air filter. Pay attention to it and heed the manufacturer’s advice.

Why is Cleaning and Changing the Air Filter Important?

Cleaning and replacing your lawn mower’s air filter is vital since it keeps the engine operating smoothly. The air filter prevents dirt and gunk from entering the engine. Unclean and clogged air filters can weaken your mower and reduce fuel efficiency. Furthermore, it might damage the engine’s internal parts, resulting in costly repairs.

By cleaning and replacing the air filter, you ensure that your lawn mower is breathing clean air, which leads to improved fuel efficiency, smoother performance, and a longer lifespan for your equipment. 

In addition to regular air filter maintenance, you should put in place a complete lawn mower maintenance plan. The more consistent you are about maintaining your mower, the longer the mower will last. Regular mower maintenance should include: 

• Changing the mower’s oil once a season or every 25-50 hours of operation
• Cleaning and changing spark plugs (if necessary) once a season 
• Sharpening the mower blades at the beginning of every mowing season
• Cleaning the underside of the mower several times throughout the season to prevent rust and caked-on dirt and grass clippings
• Winterizing the mower every year before putting it away at the end of the season

FAQ About Lawn Mower Air Filters 

Can a dirty air filter cause engine overheating?

A clogged air filter can lead to insufficient airflow, causing the engine to run hotter than usual. It could result in engine overheating and damage.

When is the best time to drain the gas from my mower? 

Drain the gas at the end of the mowing season or before long periods of inactivity to prevent fuel-related problems. For more details, consult our guide: How to Drain Gas From a Lawn Mower.

How does a push lawn mower’s air filter differ from a riding mower? 

Air filters in push mowers are generally smaller and simpler in design to match their small engine size. On the other hand, air filters in riding lawn mowers tend to be larger and more robust due to the increased engine size and power of riding mowers.

Can I reuse disposable paper air filters? 

Disposable paper filters should not be cleaned and reused when they get excessively dirty. Replace them with new filters to maintain proper filtration.

Let a Pro Take Care of Your Lawn

Lawn care involves not only seasonal care and maintenance but also keeping up with equipment, especially gas lawn mowers. Besides cleaning and changing the air filter, you have to change the oil regularly – not to mention keeping the engine fueled with ever-more-expensive gasoline. 

There are lower maintenance alternatives you might want to try if you’ve got a busy schedule. First, consider replacing your old gas mower with an eco-friendly, low-maintenance electric lawn mower. Electric mowers can be just as powerful as their gas counterparts without all the engine upkeep or fuel costs.

The other alternative is to hire a local lawn care company to take care of all your lawn care needs. Then, you won’t have to worry about taking care of your lawn, landscape, or all the equipment that goes into keeping them healthy and neat. LawnStarter can connect you with licensed, insured, trusted pros right in your backyard with just a few clicks.

Main Photo Credit: JJ Gouin / Canva Pro / License

Taha Javed

Taha Javed is a blog writer with a green thumb, sharing her expertise in lawn care and maintenance. With a knack for nurturing nature, she blends her love for writing with a passion for vibrant lawns, offering readers expert advice to transform their outdoor spaces into green havens.

Posts by Taha Javed