Why Does a Lawn Mower Start Right up and Then Shut Itself Off?

By Staff WriterLast Updated Mar 29, 2020 2:38:03 PM ET

Mowers that start and die are often suffering from unstabilized fuel that has broken down. Leaving fuel in the tank for more than a month allows the more volatile compounds to evaporate from the fuel, causing varnish to form in the tank. Other causes of this problem include leaving the packing plug in the fuel cap or a dirty air filter.