Lawn mower parts

How to fix common riding lawn mower failures

• Engine won't start. If you hear nothing—not even a click—when you turn the key to start your riding mower, then a dead battery, bad starter solenoid or failed interlock switch could be causing the problem. We walk you through the troubleshooting steps to figure out what's wrong with your mower. Once you figure out the cause of the starting failure, you can easily find the replacement parts you need using our detailed parts diagrams. We carry repair parts for common riding mower brands including Craftsman, Husqvarna, MTD, Toro, Poulan and Snapper.

• Blown fuse. Replacing a blown fuse on your riding lawn mower is easy, but finding the cause can be more difficult. Unless you locate and repair the short, you’ll just keep blowing fuses. Learn how to test your ignition switch and the engine, chassis, and dash wire harnesses to narrow down the suspects so you can repair the problem and get back to mowing.

• Flat tire. If there is a small object embedded in the tread of a tire on your riding lawn mower, you can often repair it with tire sealant. If the sealant doesn't fix the leak, or the hole is in the tire's sidewall, replace either the front tire or back tire as needed.

Top repairs for walk-behind lawn mowers

• Replacing the blade. Check the lawn mower blade often during mowing season to make sure it's sharp and intact. Replace the blade with a manufacturer-approved replacement part if it's dull, damaged or bent. A dull blade tatters the tips of the grass blades rather than making a clean slice. A damaged or bent blade cuts unevenly and can make the mower vibrate excessively. Consider keeping a spare mower blade on hand, so you can install it right away to replace a dull or damaged blade. We have a wide variety of replacement blades that fit major brands such as Craftsman, Toro, MTD, Murray, Lawn-Boy and Troy-Bilt.

• Tuning up your lawn mower engine. You can help the engine on your walk-behind lawn mower run better and last longer by giving it a tune-up at least once a year. A tune-up takes about half an hour and involves changing the oil, air filter and spark plug, along with cleaning the exhaust, controls and engine cooling system.

• Replacing the flywheel key. The flywheel key is a rectangular metal peg that keeps the crankshaft and flywheel aligned when you tighten the flywheel nut. If the mower blade hits an object with enough force to knock the flywheel out of alignment, the flywheel key breaks, protecting expensive parts such as the crankshaft from damage. If the flywheel key shears slightly, the engine runs rough or misfires. If the key breaks, the lawn mower stops running and won't start. When you try to start the engine, the starter rope might jerk back. If any of these symptoms sound familiar, you likely need to replace the flywheel key.