Abstract: A method of making a propeller includes forming the propeller to have blades coupled to an outer hub, the outer hub coupled to an inner hub via ribs, and the inner hub configured to be coupled to the marine vessel. The ribs each have first and second ends with a midpoint therebetween, an inner end and an outer end that define a width therebetween, and a leading surface and a trailing surface that define a thickness therebetween. The ribs are tapered such that the thickness is greater at the midpoint than at least at one of the first end and the second end, and scalloped such that the width is greater at the midpoint than at least at one of the first end and the second end. Each of the ribs is coupled to the outer hub in radial alignment with one of the blades.

Abstract: Shock absorbing hub assemblies and methods of making the same for marine propulsion devices having a propeller shaft and propeller. The assembly has an adapter component having an inner bore that engages the propeller shaft's splined outer surface and having a body with axially extending engagement surfaces on one end and an elastic hub component on an opposite end. The elastic hub component has planar outer engagement surfaces that abut corresponding inner engagement surfaces on the propeller hub's inner bore. Upon initial propeller shaft rotation, the elastic hub component deflects and allows the adapter component to rotationally travel relative to the propeller hub while not rotating the propeller hub. Upon further rotation, the adapter component's axially extending engagement surfaces engage with the propeller hub to rotate the propeller hub. The elastic hub component has a spring rate small enough to reduce clutch rattle yet large enough to isolate transmission shift clunk.

Abstract: A torque transmitting device and related a marine propulsion system include an adapter that comprises a first portion shaped to engage in torque-transmitting relation with a propulsor shaft of the marine propulsion system so that rotation of the propulsor shaft about the axis of rotation causes synchronous rotation of the first portion about the axis of rotation. A second portion is shaped to engage in torque-transmitting relation with a propulsor hub of the marine propulsion system. The second portion is connected to the first portion by a plurality of elongated torsional members that are integrally attached to at least one of the first and second portions. The elongated torsional members are resilient so as to allow the first portion and second portion to rotate relative to each other about the axis of rotation.

Abstract: A marine propeller is provided with a valve that progressively blocks exhaust flow into aerating relation with the blades of the propeller as the propeller rotational speed increases. A piston within a housing moves radially outwardly, in response to centrifugal forces, as the propeller increases in rotational speed. This movement progressively blocks an aperture that allows the flow of exhaust gas into the region of the propellers. In certain embodiments, a secondary flow path is allowed even when the piston has moved to its extreme outward radial position.