Abstract: A marine drive has a primary exhaust outlet on its lower gearcase that discharges a primary flow of exhaust gas from the engine to seawater in which the marine drive is situated. A secondary exhaust outlet is located on the marine drive above the primary exhaust outlet and discharges a secondary flow of exhaust gas from the engine to atmosphere around the marine drive at least when the engine is operated at an idle speed. A tertiary exhaust outlet is located on the marine drive between the primary and secondary exhaust outlets, and discharges a tertiary flow of exhaust gas from the engine to the seawater or to the atmosphere depending upon a current location of the tertiary exhaust outlet with respect to the seawater. A muffler is configured to reduce noise emanating from the tertiary exhaust outlet.

Abstract: A method of controlling an adjustable exhaust system for a marine engine includes receiving a vessel location of a marine vessel having an adjustable exhaust system and identifying a desired position of the bypass valve based on the vessel location and/or a current time. If the bypass valve is not in the desired position, an instruction is generated to adjust the bypass valve to the desired position to change a noise level generated by the adjustable exhaust system.

Abstract: A method for controlling an elastic mount configured to support a propulsion device with respect to a marine vessel, wherein the elastic mount contains an electromagnetic fluid and an electromagnet and is configured such that adjusting an amount of electricity applied to the electromagnet changes a shear strength of the electromagnetic fluid in the elastic mount and thereby controls an elasticity of the elastic mount. The method includes applying a first amount of electricity to the electromagnet to produce an initial elasticity of the elastic mount measuring an oscillation of the propulsion device with a motion sensor, determining that the oscillation of the propulsion device exceeds a threshold oscillation, and adjusting the amount of electricity applied to the electromagnet to change the elasticity of the elastic mount to reduce the oscillation.

Abstract: A method of controlling an adjustable exhaust system for a marine engine includes receiving a vessel location of a marine vessel having an adjustable exhaust system and identifying a noise constraint based on the vessel location. A current exhaust mode of the adjustable exhaust system is identified. A determination is then made regarding whether the exhaust system is exceeding the noise constraint based on the current exhaust mode. If the noise constraint is exceeded, an instruction is generated to adjust the adjustable exhaust system to comply with the noise constraint.

Abstract: A method for controlling an elastic mount configured to support a propulsion device with respect to a marine vessel, wherein the elastic mount contains an electromagnetic fluid and an electromagnet and is configured such that adjusting an amount of electricity applied to the electromagnet changes the shear strength of the electromagnetic fluid and thereby controls elasticity of the elastic mount, including applying a first amount of electricity to the electromagnet to produce a first elasticity in the elastic mount, determining that a vessel speed indicator exceeds a high speed threshold, determining that a trim position for the propulsion device is greater than a threshold trim position, detecting at least a threshold decrease in throttle demand, and applying a second amount of electricity to the electromagnet wherein the second amount of electricity is greater than the first amount of electricity, so as to decrease the elasticity of the elastic mount.

Abstract: A system for controlling exhaust flow from an internal combustion engine powering a marine propulsion device includes a primary exhaust conduit having an upstream end receiving exhaust gas from the internal combustion engine and a downstream end discharging exhaust gas to a body of water via a gearcase housing. A bypass exhaust conduit has an upstream end receiving exhaust gas from the primary exhaust conduit and a downstream end discharging exhaust gas from a bypass outlet of the marine propulsion device. A bypass valve is selectively openable to allow exhaust gas to flow through the bypass conduit. A control module is in signal communication with the bypass valve. The control module opens the bypass valve to divert the exhaust gas through the bypass conduit and out the bypass outlet in response to selection of a control mode of the marine propulsion device other than a default lever control mode.

Abstract: A marine drive has a primary exhaust outlet on its lower gearcase that discharges a primary flow of exhaust gas from the engine to seawater in which the marine drive is situated. A secondary exhaust outlet is located on the marine drive above the primary exhaust outlet and discharges a secondary flow of exhaust gas from the engine to atmosphere around the marine drive at least when the engine is operated at an idle speed. A tertiary exhaust outlet is located on the marine drive between the primary and secondary exhaust outlets, and discharges a tertiary flow of exhaust gas from the engine to the seawater or to the atmosphere depending upon a current location of the tertiary exhaust outlet with respect to the seawater. A muffler is configured to reduce noise emanating from the tertiary exhaust outlet.

Abstract: A system comprises an elastic mount configured to support a propulsion device with respect to a marine vessel. The elastic mount contains an electromagnetic fluid. An electromagnet is configured so that increasing an amount of electricity applied to the electromagnet increases the shear strength of the electromagnetic fluid in the elastic mount and thereby decreases elasticity of the elastic mount, and so that decreasing the amount of electricity applied to the electromagnet decreases the shear strength of the electromagnetic fluid in the elastic mount and thereby increases the elasticity of the elastic mount. A controller automatically adapts the amount of electricity applied to the electromagnet based on one or more sensed conditions so as to improve performance and/or handling of the marine vessel.

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 stern drive arrangement is for propelling a marine vessel in water. A diverter valve is movable into and between an open position in which the exhaust gas is allowed to flow through the above-water outlet via the secondary exhaust conduit and a closed position in which the exhaust gas is at least partially prevented from flowing through an above-water outlet via a secondary exhaust conduit. Via a bypass conduit, the exhaust gas in the secondary exhaust conduit can bypass the diverter valve and discharge to atmosphere when the diverter valve is in the closed position.

Abstract: An outboard motor includes an internal combustion engine and a cowl covering the engine. An air vent allows intake air into the cowl, an air intake duct routes the intake air from the air vent to the engine, and a throttle body meters flow of the intake air from the air intake duct into the engine. A sound enhancement device is located proximate the throttle body. A sound duct is provided, and has an inlet end located proximate the sound enhancement device and an outlet end located proximate an outer surface of the cowl. The sound enhancement device is tuned to amplify a first subset of sounds having a desired frequency that are emitted from the throttle body, and the sound duct transmits the amplified sounds to an area outside the cowl. A method for modifying sounds produced by an air intake system of an outboard motor is also provided.

Abstract: An outboard motor can be coupled to a transom of a marine vessel via the described rigging system. The rigging system includes a plurality of engine-sourced lines extending from an engine of the outboard motor, through an aperture in the motor housing, and to the marine vessel. A protective tube surrounds the plurality of engine-sourced lines and has a first end coupled to the motor housing and a second end coupled to the marine vessel. A rigging center is located aboard the marine vessel and holds distal ends of each of the engine-sourced lines. A plurality of connectors is provided on the distal ends of the engine-sourced lines. At the rigging center, each engine-sourced line is configured to be coupled, via a respective connector, to a corresponding vessel-sourced line. The vessel-sourced lines are in turn connected to respective engine-related devices aboard the marine vessel.

Abstract: Exhaust systems are for outboard marine engines that are configured to propel a marine vessel in a body of water. An intermediate exhaust conduit is configured to receive the exhaust gas from the primary exhaust conduit. A primary muffler receives the exhaust gas from a intermediate exhaust conduit. A secondary muffler receives the exhaust gas from the primary muffler. An idle relief outlet discharges the exhaust gas from the secondary muffler to atmosphere. A bypass valve is positionable into an open position wherein the exhaust gas is permitted to bypass the secondary muffler and flow from the primary muffler to the idle relief outlet and into a closed position wherein the exhaust gas is not permitted to bypass the secondary muffler and instead flows from the primary muffler to the idle relief outlet via the secondary muffler.

Abstract: An outboard motor includes an internal combustion engine powering the outboard motor and a cowl covering the engine and having a vent allowing air under the cowl. A throttle body meters flow of the air into the engine and an intake structure downstream of the throttle body delivers the metered airflow to one or more combustion chambers in a cylinder block of the engine. A sound enhancement assembly in acoustic communication with the intake structure collects sounds emitted by the engine. The sound enhancement assembly is configured to amplify a subset of the collected sounds that have frequencies within a desired frequency range. A method for modifying sounds produced by an air intake system of an internal combustion engine powering an outboard motor is also disclosed. The method includes positioning a sound enhancement assembly in acoustic communication with an air intake passageway located downstream of the engine's throttle body.

Abstract: A system comprises an elastic mount configured to support a propulsion device with respect to a marine vessel. The elastic mount contains an electromagnetic fluid. An electromagnet is configured so that increasing an amount of electricity applied to the electromagnet increases the shear strength of the electromagnetic fluid in the elastic mount and thereby decreases elasticity of the elastic mount, and so that decreasing the amount of electricity applied to the electromagnet decreases the shear strength of the electromagnetic fluid in the elastic mount and thereby increases the elasticity of the elastic mount. A controller automatically adapts the amount of electricity applied to the electromagnet during translation of the marine vessel so as to reduce the likelihood that the propulsion device impacts an adjacent structure on the marine.

Abstract: A stern drive for a marine vessel comprises a gimbal housing that is configured for connection to the transom of the marine vessel; a gimbal ring that is steerable with respect to the gimbal housing about a vertical steering axis; a drive leg that is trimmable with respect to the gimbal ring about a horizontal trim axis, wherein the drive leg supports a propulsor for propelling the marine vessel; a trim actuator that is configured to trim the drive leg about the trim axis; and a cradle that decouples the drive leg from the transom of the marine vessel and pivots with and supports the drive leg and as the trim actuator trims the drive leg about the trim axis.

Abstract: An outboard motor including a system for enhancement of a first subset of sounds having a desired frequency, and a method for modifying sounds produced by an air intake system for an internal combustion engine powering the outboard motor are described. The method includes collecting sounds emitted in an area proximate a throttle body of the engine. A first subset of the collected sounds, which have frequencies within desired frequency range, are then amplified. The amplified first subset of sounds are then transmitted to an area outside a cowl covering the engine.