Abstract: A watercraft (10) having two sources of (22, 32) of cooling water (28, 34) for injection cooling of hot exhaust gas (30) being conveyed through an exhaust pipe (16) upstream of muffler (54). The first water source (22) may be an active apparatus such as the engine cooling apparatus (22). The second source of water (32) may be a passive apparatus such as a Pitot tube (38) formed in the stern drive (20) of the watercraft (10). By providing two independent sources of cooling water, the probability of exhaust component failures is significantly reduced.

Abstract: A marine propulsion system (10) including a vertical drive unit (12) adapted to have a common upper gear case housing (26) for use with either one of a cone clutch shifting apparatus (60) or a clutch dog shifting apparatus (120). The upper gear case housing is designed to have bearing support surfaces (38) common to both applications and to have a bottom mating surface (27) adapted for attachment to a lower gear case (16) including either a clutch dog shifting apparatus (120) or a non-shifting power transfer apparatus (140). A shift linkage (110) is designed to have a first set of parts (80,82) adapted for connection to the cone clutch shifting apparatus (90) and having a second set of parts (102,104,106) adapted for connection to the clutch dog shifting apparatus (120) and having a third common set of parts (44,48,50) necessary for connection to either the cone clutch shifting apparatus or the clutch dog shifting apparatus.

Abstract: A system for propelling and steering a watercraft is provided that includes a pair of electric motor propulsion units provided aft of a transverse centerline of the watercraft hull. A rudder is provided forward of the transverse centerline. The propulsion units may be driven to provide resultant thrust to navigate the watercraft in desired directions, automatically or in response to operator command inputs. The rudder, which may be extendable and retractable, may also be angularly positionable. Where angular positioning is provided, the orientation of the rudder may also be controlled in cooperation with the propulsion units to provide reactive forces by impingement of the rudder against the water, thereby enhancing the steering offered by the propulsion units.

Abstract: A hull for a marine propulsion system includes recesses for receiving and protecting propellers of the propulsion systems. The hull may be designed with a pair of recesses, such as in a stern region, in which props of two separate electrically driven propulsion units are positioned. The recesses are formed integrally with the hull shell, and present open lower and aft regions for free circulation of water displaced by the props. The recesses may also properly orient thrust from the props, such as at oblique angles with respect to a centerline of the hull. The recesses may be formed in the hull for receiving the propulsion units as an optional package. A top surface of each recess forms an integral cavitation plate for reducing or eliminating air entrainment into the water stream around the props as well as cavitation due to localized low pressure regions during operation.

Abstract: A marine propulsion device comprising a propulsion unit which is adapted to be mounted on a boat transom and which includes an exhaust passageway having an upstream end adapted to communicate with an engine, and a mechanism for introducing water into the exhaust passageway at a location downstream of the upstream end.

Abstract: A stern drive unit comprising a gimbal housing which is adapted to be mounted on the transom of a boat and which has therein an exhaust-water passage including a forwardly opening inlet, a rearwardly opening outlet, an exhaust conducting portion, a water conducting portion, and a water outlet communicating with the water conducting portion.

Abstract: A marine propulsion device comprising a housing adapted to be mounted on the transom of a boat, a first gear rotatably supported by the housing and adapted to be drivingly connected to a propeller, a pump, and a second gear which is driven by the first gear and which is drivingly connected solely to the pump.

Abstract: A marine propulsion device comprising a lower gearcase, a bearing housing which is supported by the lower gearcase and which includes an exterior surface having therein an annular groove, a propeller shaft rotatably supported by the bearing housing and adapted to have mounted thereon a propeller, and a retaining member which is supported by the lower gearcase and which extends into the groove.

Abstract: A marine propulsion device comprising a gear housing adapted to be mounted on the transom of a boat, a lever mounted on the gear housing for pivotal movement relative thereto about a first axis, a clutch mechanism supported by the gear housing, a mechanism for actuating the clutch mechanism in response to pivotal movement of the lever, a link, a mechanism connecting the link to the lever for pivotal movement relative thereto about an axis spaced from the first axis, a guide member adapted to be connected to a control mechanism, a mechanism for guiding movement of the guide member relative to the gear housing, and a mechanism for connecting the guide member to the link.

Abstract: A marine propulsion device comprising a gear housing adapted to be mounted on the transom of a boat, a clutch assembly including a clutch housing, a shaft rotatably supported within the clutch housing and adapted to be drivingly connected to a propeller, opposed bevel gears coaxially supported within the clutch housing for rotation relative to the shaft, and a clutch mechanism located between the bevel gears for causing selective and alternative driving engagement of the bevel gears and the shaft, and a mechanism for affording insertion of the clutch assembly as a unit into the gear housing and for affording removal of the clutch assembly as a unit from the gear housing.

Abstract: A marine propulsion device comprising a gear housing adapted to be mounted on a transom of a boat, a first gear rotatably supported by the gear housing and adapted to be driven by an engine, a second gear which is rotatably supported by the gear housing, which is driven by the first gear and which is adapted to be drivingly connected to a propeller, a third gear driven by the second gear, and an arrangement for lubricating the third gear.

Abstract: A marine propulsion device comprising a member adapted to be mounted on the transom of a boat, a housing which is mounted on the member for pivotal movement relative thereto and which has therein a first bore, an extendable and contractable hydraulic assembly having a first end connected to the member and having a second end having therein a second bore, a shaft extending through the first and second bores, a bushing surrounding the shaft in the first and second bores, and an elastomeric member surrounding the bushing in the first and second bores.

Abstract: A marine propulsion device comprising a gear housing adapted to be mounted on the transom of a boat, a drive shaft rotatably supported by the gear housing and adapted to be drivingly connected to a propeller, a clutch mechanism supported within the gear housing and operably connected to the drive shaft, an actuating member movably supported by the gear housing and including a portion extending exteriorly of the gear housing, and a mechanism mounted on the gear housing for forming a substantially water-tight chamber containing the portion of the actuating member.

Abstract: A stern drive unit comprising a metal upper gear housing which is adapted to be mounted on the transom of a boat for pivotal movement relative thereto about a generally vertical steering axis and about a generally horizontal pivot axis, a generally vertical drive shaft rotatably supported by the upper gear housing and adapted to be driven by an engine, a lower gear housing fixed to the upper gear housing for common movement therewith, a propeller shaft which is rotatably supported by the lower gear housing, which is driven by the vertical drive shaft and which is adapted to have mounted thereon a propeller, and plastic covers covering more than a majority of the upper gear housing.

Abstract: A stern drive unit comprising a gimbal ring adapted to be mounted on the transom of a boat for pivotal movement relative thereto about a generally vertical steering axis, the gimbal ring including a rearward surface, and a lateral support portion extending rearwardly from the rearward surface, and a housing mounted on the gimbal ring for pivotal movement relative thereto about a generally horizontal tilt axis, the housing including a forward surface, and a lateral support portion extending forwardly from the forward surface and adjacent the gimbal ring lateral support portion.

Abstract: A marine propulsion device comprising a gear housing adapted to be mounted on the transom of a boat, a bearing housing supported by the gear housing, a bearing mechanism supported by the bearing housing, a propeller shaft supported by the bearing mechanism and adapted to have mounted thereon a propeller, a sacrificial anode, and a mechanism for securing the anode to the bearing housing.

Abstract: A marine propulsion device comprising a pivot housing including an opening, and a lip extending inwardly around the opening, a flexible bellows having an end complementary with and communicating with the opening in the pivot housing, the end of the bellows including a flange engaged with the lip, a propulsion unit removably connected to the pivot housing and including a portion engageable with the end of the bellows for compressing and securing the flange against the lip on the pivot housing so that the flange sealingly engages the pivot housing when the propulsion unit is connected to the pivot housing.

Abstract: A marine propulsion device comprising a pivot housing adapted to be mounted on a boat transom for pivotal movement relative to the boat transom about a generally vertical steering axis, and for pivotal movement relative to the boat transom about a generally horizontal tilt axis, a propulsion unit including a reversible transmission and being removably connected to the pivot housing for pivotal movement with the pivot housing, and a mechanism extending between the pivot housing and the propulsion unit for actuating the transmission from the pivot housing, the mechanism being disengaged incident to disconnection of the propulsion unit from the pivot housing, and being engaged incident to connection of the propulsion unit to the pivot housing.

Abstract: Disclosed herein is a marine propulsion device comprising a lower unit including a gearcase, a propeller shaft rotatably mounted in the gear case and adapted to support a propeller, a clutch shaft rotatably mounted in the gearcase in co-axial relation to the propeller shaft, a splined female end portion on one of the propeller shaft and the clutch shaft and a splined male end portion on the other of the propeller shaft and the clutch shaft and engaged with the splined female end portion, and a resilient spring clip cooperating with the propeller shaft and the clutch shaft for releasably retaining the propeller shaft and the clutch shaft in predetermined axial relation to each other.

Abstract: Disclosed herein is a marine propulsion device comprising a lower unit including a gearcase, a driveshaft having an end extending into the gearcase, a pinion mounted on the end of the driveshaft, a propeller shaft bearing housing located within the gearcase having a forward end adjacent the pinion, a propeller shaft rotatably mounted in the propeller shaft bearing housing and having a rear end portion and a portion forwardly of the rear end portion, a propeller mounted on the rear end of the propeller shaft, a bevel gear adjacent the forward end of the propeller shaft bearing housing and engaging the pinion, the bevel gear including an annular forwardly facing thrust transferring surface, and an annular thrust transferring element mounted on the propeller shaft bearing housing and engageable with the annular forwardly facing thrust transferring surface so as to transfer thrust forwardly from the bevel gear through the thrust transferring element and to the propeller shaft bearing housing.