SAFETY CIRCUITS FOR GRASS MOWER An electrical shorting system for shorting the ignition system of an internal combustion engine on a tractor or the like to prevent the starting of the engine and to stop the engine when operating unless switches of the shorting system are so set by operating conditions and positions of parts of the tractor or the like. The shorting system is arranged so that unless switches in an electrical circuit of the shorting system are set or maintained in proper position by operations of the tractor or the like, (such as the clutch of a grass cutting unit carried by the tractor or the like, such as the clutch of the drive mechanism of the tractor or the like, such as by the occupancy of non-occupancy of the seat of the tractor or the like, or such as the connection or dis-connection of a grass catcher to the tractor or the like) the ignition system of the engine is short circuited and the engine is inoperative.
