Lawn Mowers & Trimmers

A practical diagnostic order for a self-propelled walk-behind mower that will not move, moves slowly, or has drive wheels that will not pull.

White or bluish-white mower smoke often points to oil where it should not be. Start with the oil level, recent tipping, and air-filter area before assuming major engine damage.

A practical diagnostic order for a gas mower that is difficult to start after storage, beginning with old fuel, primer use, spark plug condition, and airflow.

A mower that dies as the PTO or blade control engages may have an interlock issue, a deck problem creating too much load, or an engine that cannot hold mowing RPM.

A practical diagnostic order for a string trimmer line that will not feed, including spool jams, welded line, worn eyelets, and correct reloading.

If the engine runs but the cutting head stays still, inspect for wrapped debris, a seized head, drive-shaft trouble, or a worn clutch.

If your mower leaves narrow bands of standing grass, inspect blade condition, deck buildup, deck level, tire pressure, and blade-drive components in a sensible order.

A mower cord that will not pull may point to a held safety brake, jammed blade area, flooded cylinder, recoil damage, or internal engine trouble.

A mower that starts normally but stalls shortly afterward often has a fuel-delivery, airflow, ignition, or carburetor issue. Use this safe diagnostic order to narrow it down.

What It Means When a Mower Runs Only With the Choke On If your lawn mower only runs with choke on after warming up, it may not be receiving enough fuel for the air entering the engine. Partly closing the choke enriches the mixture. An improvement is a useful clue, but it does not identify…