My Craftsman Pull Cord Tiller Will Not Start

Check the Fuel

• Old or bad gas in a two-cycle engine causes a majority of all starting problems. When the gas destabilizes and dries out, usually after 30 days, it leaves behind a gummy deposit on the fuel lines and inside the carburetor. This will eventually restrict the flow of fuel from the tank to the carburetor and cause starting problems. Never leave fuel in the tank or engine for longer than two weeks. If you’re storing the tiller, drain the tank and run the engine dry. If bad or old gas is already present in the tank or engine, dump out any fuel in the tank and refill it with freshly mixed fuel.

Check the Air Flow

• For the combustion process to work, the fuel mixture needs to mix with air. Any impurities in the air can damage the engine, so it must first pass through a filter before reaching the fuel mixture. If this filter gets too dirty, air will stop flowing into the engine, and the tiller won’t start, or it may start and run for a few seconds then die. Air filters need to be washed and cleaned every 12 to 15 hours of operation and replaced seasonally. Clean around the air filter box and the carburetor while the filter is removed.

Check the Spark Plug

• The spark plug sits on the underside of the engine and regulates the release of the spark needed to ignite the fuel. However, after each spark, a small amount of un-vaporized fuel builds up on the metal tip of the plug. After enough hours of operation, the metal tip will get covered in a black layer that prevents the discharge of electricity. Spark plugs need to be replaced at least once a season, preferably at the beginning.

Other Common Issues

• If old or bad gas has built up a thick gummy layer inside the carburetor, fuel and air won’t mix properly, and the engine won’t start. Carburetors, over time, can also get warped or filled with moisture, preventing proper fuel and air mixing. Dirt and other impurities can also cause a blockage. If the tiller is old or used frequently, the ignition module may need to be replaced. Fuel and air leaks inside the engine can also cause many starting problems. These problems all require a professional service mechanic.