Abstract: An operation control system for a small boat can include a mode selection module configured to allow a driver to select between a plurality of driving modes including at least a normal operation mode, in which the boat cruises at a speed in response to the displacement of an acceleration controller, and a low-speed setting mode, in which the boat cruises at a preset low speed when a low-speed setting controller is operated; in which the mode selection module permits the driving mode to switch to the low-speed setting mode if the displacement of the acceleration controller is zero, or small or close to zero or is in or substantially at an idle position.

Abstract: A marine propulsion device having a pair of outboard motors each of which has a sensing device for sensing an abnormal running condition, a warning device for indicating a warning of the abnormal running condition and a control device for slowing the speed of the engine in response to the sensed abnormal running condition. An arrangement is provided wherein the sensing of an abnormal running condition of either engine is effective to slow the speed of both engines and provide the abnormal running condition indication for both engines. The normal engine may be reset to full speed control in response to shifting of the normal running engine either into a neutral condition or by slowing or stopping of it.