What Causes a Lawn Mower to Backfire?
A lawn mower backfires when unburned fuel ignites in the hot exhaust system. Common causes include a lean fuel mixture from a clogged carburetor or dirty air filter, incorrect ignition timing, a stuck exhaust valve, or shutting the engine off too quickly while it's still hot. This guide explains each cause and walks you through simple DIY troubleshooting.
