Mower Starts but Keeps Shutting Off: Easy Troubleshooting

If your mower starts up but repeatedly dies, this is a common problem that can often be fixed with a few simple steps at home. Most issues are related to fuel, air, or spark delivery to the engine. Below are the easiest things to check before bringing your equipment in for repairs.

Things to Check When Your Mower Keeps Shutting Off

• Check the Fuel

  • Make sure there’s fresh gasoline. Old or stale gas (older than 30 days) can cause the engine to shut off.

  • Look for contaminated fuel or water in the tank.

• Inspect the Air Filter

  • A clogged air filter can choke the engine. Remove the filter and check if it’s dirty or packed with debris. Clean or replace it if needed.

• Examine the Fuel Filter and Line

  • A blocked fuel filter or fuel line will starve the engine of gas. Replace the filter if it looks clogged, and inspect the line for cracks or blockages.

• Clean the Carburetor

  • Dirt and residue can block the carburetor, stopping fuel from mixing with air. Many carburetors can be cleaned by spraying carburetor cleaner into the intake; for more severe buildup, removal and cleaning may be needed.

• Check the Spark Plug

  • Remove the spark plug and inspect for wear, cracks, or carbon buildup. Clean it with a small wire brush or replace it with a new one.

• Test the Fuel Cap

  • Make sure the fuel cap vent is clear. A blocked vent can create a vacuum in the tank, causing the mower to die. Try loosening the cap slightly and see if your mower stays running.

• Inspect for Blade or Deck Obstructions

  • Built-up grass and debris around the blades can put extra strain on the engine and cause stalling. Always disconnect the spark plug before cleaning under the mower.

If These Don’t Fix Your Mower…

If you’ve tried all the steps above and your mower still shuts off, the issue may be more complex, such as a faulty ignition coil, safety switch, or deeper fuel system problem. Don’t worry – Koenig Equipment is here to help.

Koenig Equipment’s certified technicians are fully trained to diagnose and repair all mower and tractor issues. Whether it’s a carburetor that needs rebuilding, an electrical problem, or anything else, our team can get your mower running reliably again.

Our friendly staff can inspect, repair, and return your mower to you quickly so you can get back to enjoying a worry-free lawn. Click here to schedule service > 

Tip:
Prevent mower problems by following regular maintenance, using only fresh gasoline, and having your mower serviced by Koenig Equipment at least once a season for best performance.