A properly functioning air filter is your mower's first line of defense is kicking up dust and debris during mowing. When the air filter is in good condition and working properly, it prevents dust from entering the engine through the carburetor. But if the air filter is worn, dust and other debris can make their way into the engine. Cleaning or replacing the air filter are some simple lawn mower repairs that will improve performance and extend the life of your mower.Clean the foam pre-cleaner every 25 hours. Replace the paper air filter quarterly or after 300 hours. In dusty conditions, more frequent cleaning and replacement may be necessary.A lawn mower's air filter is usually located on top of the engine and is encased in a metal or plastic cover that is usually held in place by a screw or clip. There are several types of air filters on the...