Abstract: An acceleration control system is provided which allows the operator of a marine vessel to select an acceleration profile to control the engine speed of a marine vessel from an initial starting speed to a final desired speed. When used in conjunction with tow sports, such as wake boarding and water skiing, the use of acceleration profile provides consistent performance during the period of time when a water skier is accelerated from a stationary position to a full speed condition.

Abstract: An exhaust system for a marine engine provides individual exhaust gas conduits that are maintained separately from water conduits until the individual exhaust gas conduits can be combined within a common exhaust gas conduit. This combination of exhaust gas streams allows the amplitude of negative pressure pulses to be damped, by combination with each other, prior to the mixing of cooling water with the exhaust gas streams. Later, the combined exhaust gas stream can be mixed with a combined water stream.

Abstract: A muffler is provided for a marine propulsion system in which an initial portion causes a downward flow of exhaust gas and entrained water from an exhaust manifold. The transition section directs the exhaust gas toward an egress section which extends upwardly from the transition section. The various sections of the exhaust path can be configured to form one or more loops which define one or more water collection regions.

Abstract: A marine propulsion system is provided with a liquid detector located within a cooling passage of the cooling system of an engine. Conductivity sensors, or other types of liquid sensors, provide signals representative of the absence or presence of water at particular locations within the cooling system. The signals are used to energize and de-energize various annunciators on a display panel to inform the operator of a marine vessel of the status of a draining procedure. When all of the annunciators properly indicate the absence of water within strategic locations of the cooling system, the marine vessel operator can be assured that the draining procedure has been effectively completed.

Abstract: A coupling device is provided with two flanges and a resilient annular member disposed between facing surfaces of the flanges. The resilient annular member is provided with a central opening through which a metallic spring is disposed to exert a resistive force against compression of the resilient annular member between the two flanges. The device is particularly well suited for use in a marine propulsion system because of the propulsive force exerted on the shaft system by the propeller. In one particularly preferred arrangement, each of the two flanges is provided with three holes, and the resilient annular member is provided with six holes. The two flanges are offset rotationally to place each of the holes of one flange in alignment with an interstitial space between the holes of the other flange.