Abstract: A marine drive is for propelling a marine vessel in a body of water. The marine drive comprises a motor housing defining a motor cavity; a motor disposed in the motor cavity; a propulsor shaft extending from the motor housing, wherein the motor is configured to cause rotation of the propulsor shaft; a propulsor which is rotated by the propulsor shaft to create a thrust force in the body of water; and a vent conduit having a first end connected to the motor cavity and a second end which vents the motor cavity to atmosphere.

Abstract: A method for controlling a marine propulsion device having an engine rotatably engaged with a transmission via a clutch, and rotatably engaged with a charging device for charging a battery. The method includes measuring a voltage of the battery and comparing the voltage to a minimum threshold. The method further includes increasing a speed of the engine when the voltage is below the minimum threshold, and also increasing a slip of the clutch when the speed of the engine is increased in response to the voltage being below the minimum threshold.

Abstract: A system for suspending a lubricant in a marine propulsion device having a gearcase, the gearcase defining a gearset cavity for containing a propeller shaft gearset rotated by a driveshaft. The system includes a pump device configured to pump the lubricant away from the gearset cavity, and a reservoir located away from the gearset cavity and configured to receive the lubricant from the pump device. An input passage conveys the lubricant from the pump device to the reservoir, and an output passage conveys the lubricant from the reservoir to the gearset cavity. The reservoir is configured to retain a portion of the lubricant circulating between the gearset cavity and the reservoir.

Abstract: A propulsion device for rotating a propulsor to propel a marine vessel. The propulsion device includes a drive housing having a cavity that extends along a first central axis. A motor is positioned within the cavity. The motor rotates a shaft extending along a second central axis that is non-coaxial with the first central axis. The shaft is configured to rotate the propulsor to propel the marine vessel.

Abstract: A stern drive is for propelling a marine vessel in water. The stern drive has an upper drive unit with a lower mounting surface; a lower gearcase coupled to the lower mounting surface and a trailing end surface that is angled relative to the lower mounting surface; and a propeller shaft extending forwardly from the lower gearcase and being configured to rotate a propeller for pulling the marine vessel in the water. The upper drive unit and the lower gearcase are configured such that when a forward side of the lower gearcase impacts an underwater obstruction, the lower gearcase is caused to pivot relative to the upper drive unit until the trailing end surface impacts the lower mounting surface, which thereby causes the lower gearcase to completely uncouple from the upper drive unit.

Abstract: A method for controlling a marine propulsion device having an engine rotatably engaged with a transmission via a clutch, and rotatably engaged with a charging device for charging a battery. The method includes measuring a voltage of the battery and comparing the voltage to a minimum threshold. The method further includes increasing a speed of the engine when the voltage is below the minimum threshold, and also increasing a slip of the clutch when the speed of the engine is increased in response to the voltage being below the minimum threshold.

Abstract: A system for suspending a lubricant in a marine propulsion device having a gearcase, the gearcase defining a gearset cavity for containing a propeller shaft gearset rotated by a driveshaft. The system includes a pump device configured to pump the lubricant away from the gearset cavity, and a reservoir located away from the gearset cavity and configured to receive the lubricant from the pump device. An input passage conveys the lubricant from the pump device to the reservoir, and an output passage conveys the lubricant from the reservoir to the gearset cavity. The reservoir is configured to retain at least 15% of the lubricant circulating between the gearset cavity and the reservoir.

Abstract: A stern drive is for propelling a marine vessel in water. The stern drive has an upper drive unit with a lower mounting surface; a lower gearcase coupled to the lower mounting surface and a trailing end surface that is angled relative to the lower mounting surface; and a propeller shaft extending forwardly from the lower gearcase and being configured to rotate a propeller for pulling the marine vessel in the water. The upper drive unit and the lower gearcase are configured such that when a forward side of the lower gearcase impacts an underwater obstruction, the lower gearcase is caused to pivot relative to the upper drive unit until the trailing end surface impacts the lower mounting surface, which thereby causes the lower gearcase to completely uncouple from the upper drive unit.

Abstract: A stern drive is for propelling a marine vessel in water. The stern drive has an upper drive unit with a lower mounting surface; a lower gearcase coupled to the lower mounting surface and a trailing end surface that is angled relative to the lower mounting surface; and a propeller shaft extending forwardly from the lower gearcase and being configured to rotate a propeller for pulling the marine vessel in the water. The upper drive unit and the lower gearcase are configured such that when a forward side of the lower gearcase impacts an underwater obstruction, the lower gearcase is caused to pivot relative to the upper drive unit until the trailing end surface impacts the lower mounting surface, which thereby causes the lower gearcase to completely uncouple from the upper drive unit.

Abstract: A stern drive is for propelling a marine vessel in water. The stern drive is configured to power a propulsor located below the surface of the water. The stern drive comprises an internal combustion engine that powers a driveshaft that axially extends through a transom of the marine vessel; an exhaust manifold that conveys exhaust gas from the internal combustion engine; and an elongated exhaust conduit that redirects the exhaust gas from the exhaust manifold transversely with respect to the driveshaft. The elongated exhaust conduit conveys the exhaust gas to an upstream exhaust outlet that discharges the exhaust gas through the transom below the surface of the water and then to a downstream exhaust outlet that is spaced apart from and is located vertically higher than the upstream exhaust outlet. The elongated exhaust conduit functions as a water lift muffler during operation of the stern drive.

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: A stern drive is for a marine vessel. The stern drive comprises a gimbal housing that is configured for connection to the marine vessel, a gimbal ring that is steerable with respect to the gimbal housing about a vertical steering axis, a driveshaft housing that is connected to the gimbal ring, and a trim actuator that is configured to trim the driveshaft housing about a horizontal trim axis. The trim actuator has a first end that is pivotably connected to the gimbal ring at a horizontal first pivot axis and a second end that is pivotably connected to the driveshaft housing at a horizontal second pivot axis. A resilient driveshaft housing vibration isolator is located along the second pivot axis. The resilient vibration isolator isolates vibration forces on the driveshaft housing. A resilient gimbal ring vibration isolator is located along the trim axis. The gimbal ring vibration isolator isolates vibration forces on the gimbal ring.

Abstract: A mounting assembly for a stern drive engine including a mounting base, an engine mounting foot or bracket for securing an engine to a watercraft, and a lock ring for securing the engine mounting bracket in a constant position relative to the mounting base. The mounting base includes a threaded mounting bolt to receive a first adjustment nut, the engine mounting bracket, the lock ring and a second nut. The bottom surface of the locking ring engages a top surface of the engine mounting bracket with a downwardly extending arm or arms of the lock ring extending through an aperture in the engine mounting bracket to engage the first adjustment nut. The threaded bolt of the mounting base extends through apertures of the engine mounting bracket platform and mounting ring, and a second nut engages the top surface of the lock ring, preventing rotation of the first adjustment nut, and ultimately limiting movement of the marine stern drive engine.

Abstract: An apparatus is for mounting a marine drive to a hull of a marine vessel. An outer clamping plate faces an outside surface of the hull and an inner clamping plate faces an opposing inside surface of the hull. A marine drive housing extends through the hull. The marine drive housing is held in place with respect to the hull by at least one vibration dampening sealing member that is disposed between the inner and outer clamping plates. A first connector clamps the outer clamping plate to the outside surface of the hull and a second connector clamps the inner clamping plate to the outer clamping plate. The inner and outer clamping plates are held at a fixed distance from each other so that a consistent compression force is applied to the vibration dampening sealing member.

Abstract: A system and method for combined control of steering and trim of a marine engine unit. The system and method includes a steering apparatus generating steering signals, a trim control generating trim signals, an electronic unit receiving steering trim and cylinder position signals and sending output signals. A port hydraulic cylinder and a starboard hydraulic cylinder that extend and retract are included. The cylinders connected to first and second port and starboard joints to provide movement of the engine unit. The first and second port and starboard joints enable movement of the engine unit vertically and horizontally when the port and starboard hydraulic cylinders are extended and retracted to provide a full range of steering and trim movement of an engine unit using only two hydraulic cylinders.

Abstract: A flywheel housing is for a stern drive of a marine vessel. The flywheel housing comprises an inner mounting face for connection to an engine block of an internal combustion engine of the stern drive and an outer mounting face for connection to a gimbal housing. The inner mounting face and outer mounting face are on opposite axial sides of the flywheel housing. A conduit is formed in the flywheel housing and is configured to receive and discharge exhaust gases from the internal combustion engine. The conduit comprises an inlet port through which the exhaust gases are received from the internal combustion engine and an outlet port through which the exhaust gases are discharged from the flywheel housing.

Abstract: Methods and systems are for corrosion protection on marine vessels. A marine drive is for propelling a marine vessel in saltwater. The marine drive includes a generally planar outer running surface and a collection area located proximate to the outer running surface. An electrode conducts electricity from a source of electricity to the saltwater such that the electricity reacts to the saltwater and generates chlorine gas bubbles that tend to cause corrosion on the outer running surface. The electrode is mounted on the marine drive and protrudes out from and at an angle to the outer running surface so as to inhibit flow of the chlorine gas bubbles towards the collection area at least when the marine vessel is stationary.

Abstract: A hydraulic valve, such as a rotary valve, is connected in fluid communication with a hydraulic actuator that, in turn, causes a clutch to move between forward, neutral, and reverse gear positions. A marine transmission is caused to shift between these gear positions in response to movement of a spool of the hydraulic valve, which can be a rotary valve. Movement of the valve causes an actuator to move to the selected gear position and maintain that gear position until a subsequent movement of the hydraulic valve.