Official Simplicity mower attachment parts

Common replacement parts for Simplicity mower attachments

• Blades. The cutting blades attach to the blade hub under the mower deck and spin to cut the grass during mowing.
• Spark plug. The spark plug ignites the air and fuel mixture in the cylinder to start the lawn mower attachment engine. If the engine runs rough or is hard to start, check the spark plug and replace it.
• Air filter. The mower attachment engine's air filter removes contaminants from air before it reaches the engine, to help reduce engine wear and improve efficiency.
• Flywheel key. The flywheel key is a small metal rectangle that keeps the crankshaft and flywheel aligned when you tighten the flywheel nut. To protect more expensive components from damage, the flywheel key is designed to shear if the mower attachment blade hits an object hard enough to make the flywheel slip out of alignment with the crankshaft.

What to do when your Simplicity mower attachment's engine runs rough

If your mower attachment engine cuts out, smokes, idles poorly, vibrates or runs erratically, it could need a good tune-up to replace the spark plug, oil and air filter. Or the problem could be with the engine's fuel system. Rebuild or replace the carburetor if the engine isn't getting a good supply of fuel.

If the engine misfires, backfires, sputters or jerks the starter rope out of your hand when you try to start it, the flywheel key could be broken. A broken flywheel key disrupts the ignition timing because the magnets aren't passing the ignition coil in synchronization with piston movement. Replace the flywheel key if it's damaged or broken.