Official Stanley rear-engine riding mower parts

Troubleshooting your Stanley rear-engine riding mower when it 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. Replace the alternator if it isn't charging the battery.

Stanley rear-engine riding mower common replacement parts

• Seat switch. The seat switch recognizes whether you are sitting on the seat. If the seat switch doesn't detect you in the seat when you release the brake, the switch kills the engine. To prevent tampering, the seat switch also kills the engine when you release the brake if you unplug the seat switch wire harness.
• Starter motor. The starter motor spins the flywheel to start the engine when you turn the key to the start position.
• Oil filter. An oil filter is a filter designed to remove contaminants from engine oil, transmission oil, lubricating oil or hydraulic oil.
• Idler tension spring. The idler tension spring is used to pull the idler arm back to tighten the belt. The spring will usually connect to the idler arm on one end, and to the frame on the other.
• Ground drive belt. The ground drive belt connects the engine crankshaft to the transaxle pulley to drive the rear wheels.