Lawnmowers are commonly used tools by both homeowners and landscapers. Whether a landscaping professional or a weekend warrior, performing routine maintenance on a lawn mower is important to keep it running smoothly and to extend the life of the machine.

Routine Mower Care

There may come a time when a lawn mower will have to be replaced. However, the following 10 routine maintenance steps will help extend the life of the mower. Taking these steps will also help owners avoid more expensive lawn mower repair projects in the future.

Step 1. Stabilize the Fuel

Fuel that sits in a mower for a long period of time can clog a carburetor. Operating a lawn mower often during the mowing season will prevent this from happening. However, if a mower goes more than 30 days at a time without being used, a fuel stabilizer needs to be added. A fuel stabilizer costs less than ten dollars at a local lawn and garden store. Adding a fuel stabilizer when preparing the mowing for storage in the off-season, is also recommended. If not done, when the mowing season starts again in the spring, people may have to pay to have the carburetor professionally cleaned. Always read the instructions on the container carefully before using a fuel additive. Follow the recommended dosage and application instructions. Also, check your equipment owner’s manual for details and information.

Step 2. Change the Oil

Changing the oil in a lawn mower extends the life of the engine. The moving parts inside the engine undergo friction, which causes heat. Eventually, this heat causes parts to break down, so those parts must be lubricated with oil. Be sure to refill the oil reservoir to the designated mark on the dipstick. Remember too much oil can be just as bad for the engine as too little oil. Using premium oil will improve engine operation, lubrication, and fuel economy. As a reminder, please read your owner’s manual to perform the oil change based on the recommended hours for the particular equipment.

Step 3. Get a Reliable Battery

A freshly charged battery can improve the efficiency of lawn equipment. A mower needs a certain amount of voltage to power its lights, sensors, blades, starter, and coil.

Step 4. Keep the Deck Clean

Keep the area beneath the mower deck free of grass clippings to reduce rust buildup. Using water is good, but always remember to wipe the deck off after rinsing the mower. Use a blower or a bristled scrubber to remove buildup on hard-to-reach surfaces. Some people use a silicone spray to prevent future buildup on and under the deck.

Step 5. Replace the Spark Plugs

Spark plugs play a critical role in any engine as it relates to fuel combustion. An engine will not start without the proper amount of electricity from the spark plug. A spark plug needs replacing every 100 hours. If an engine runs roughly, there is a good chance that it might need replacing. Always check the owner’s manual for specifics on replacing spark plugs. The price of one spark plug can range from five to ten dollars, depending on the size of the equipment.

Step 6. Sharpen the Blades

Mower blades are critical when it comes to cutting grass. Remember to keep blades sharpened and balanced. When a mower has dull blades, the motor requires additional power to turn the blades. At that point, the blades are not making a smooth cut. They tear off the end of the grass, causing the grass to cast a white appearance over a yard for a few days.

People should sharpen their blades often if they have fast-growing grass that requires frequent mowing. It is also wise to keep an extra set of blades available just in case they are needed. The cost of the blades is around thirty dollars, depending on the size of the equipment. For safety reasons, only use blades that are recommended for that particular model of lawn mower by the manufacturer.

 Step 7. Check the Air Filter

Cleaning the air filter allows the engine to receive the proper amount of air it needs to get the optimal fuel-to-air ratio for successful combustion within the engine. As a mower cuts grass, small dust particles and grass clipping are attached to the air filter, along with the air that is needed for the engine to run. Clean the filter with a mild detergent or, if the filter is too worn to clean, replace it with a new one. Revisit the service manual to determine the recommended intervals for cleaning and replacement. The cost of an air filter is less than ten dollars, depending on the size of the equipment.

Step 8. Replace the Fuel Filter

Clean fuel is essential when it comes to an engine running smoothly and efficiently. The fuel filter cleans all of the fuel that comes from the fuel tank to the engine. Particles from a gas container may fall in the fuel tank of the equipment. The filter will clean the fuel as it passes through, resulting in a much easier process of fuel delivery.

Smaller lawn equipment usually does not carry a fuel filter, but large- to medium-sized equipment typically comes with one to help with the filtration of the fuel. Regularly check and replace the fuel bulb primer on smaller equipment. Review the service manual to determine recommended intervals for cleaning and replacing filters and primer bulbs.

Step 9. Check Tire Pressure

Believe it or not, proper tire pressure can affect how level the grass is cut. If the tire pressure on a mower is low on one or more tires, it will make the deck cut the grass unevenly. Proper tire pressure makes the difference between a good ride on a mower or a bumpy one. Furthermore, pushing and pulling the unnecessary weight of flat tires will cause friction to be placed on the engine and transmission. Routinely check the air pressure and the condition of the tires.

Step 10. Service the Belts

Check for cracks and worn spots in the belts to eliminate any breakage and improper turning with the pulleys. If the equipment is used to cut a hill and the belts are worn, it will not have the power it needs to operate at full capacity. Also, belts function to turn the pulleys with the blades attached. If the belts are old with cracks, the equipment will not have the full power to cut the grass with ease.

Maintain Mower Care

Carefully follow all manufacturers’ instructions for routine repair in the lawn mower service manual. Following the service manual and these ten steps will help maintain a lawn mower for years to come. Visit the Alabama Extension Urban Lawn and Garden page for more information on urban landscaping.

Marcus Garner, Urban Regional Extension Agent, Home Grounds, Gardens, and Home Pests, Alabama A&M University

Revised November 2023, The 10 Steps of Lawn Mower Maintenance