MTD Lawn & garden engine Parts — Browse All Models

What to do when your MTD riding mower engine won't start

There are numerous explanations for why a riding lawn mower won't start, including everything from bad gas or a bad battery to a failed starter motor or bad ignition coil.

If you find yourself constantly having to charge the battery before starting the engine, a bad battery or failed alternator could be causing the problem. Connect the battery to a charger and if the battery won't charge fully within 8 hours, then you'll likely need to replace the battery. If the battery is okay, then a problem in the engine's charging system is causing the constantly drained battery. The engine uses an alternator to generate current, which constantly charges the battery and powers the mower's electrical system while the engine runs. When the alternator fails, the battery attempts to power the mower on its own and quickly drains without recharging.

If the engine spins but won't start when you turn the ignition key, the engine is missing one of its key ingredients for starting-fuel, compression or spark. Check your basics first, then watch our riding mower engine spins but won't start video for troubleshooting tips to get the engine started.

Top-selling MTD lawn and garden equipment engine parts

• Starter motor. The starter motor spins the flywheel to start the engine when you turn the key to the start position.
• Carburetor rebuild kit. The carburetor rebuild kit includes gaskets, seals, a hinge pin and other components to refurbish the carburetor.
• Alternator. The alternator is a set of wire coils under the flywheel of the engine that generates electricity to power the tractor when it's running. The alternator also recharges the battery while the engine runs.
• Battery. On electric start engines, the battery provides the 12 volts needed to power the starter.
• Fuel pump. The fuel pump moves fuel from the fuel tank to the engine.