Abstract: A marine drive unit in combination with a coupling (6) between the engine (4) and the propeller drive unit (2). The unit has a divided flywheel cover (20), the proximal portion (22) of which is joined to the engine and has an axially extending section (25) with a connecting portion (38), which has, as seen in the drawing, an inner profile which is upwardly tapered both longitudinally and transversely to the drive unit. A primary shaft (16) is joined via drive knuckles (15) to the propeller drive unit (2) and is borne in a bearing (28) mounted in a seat (27) in a first end of a bearing holder (26). The primary shaft (16) engages a flywheel (19). The other end of the bearing holder (26) is joined to the distal portion (24) of the flywheel cover. The distal portion (24) has a supporting portion (31) with an exterior profile complementary to the interior profile of the connecting portion (38).

Abstract: Stern drive for boats, including a drive shaft housing rotatably journalled in a pivotal fork-shaped support bracket. Trim cylinders between a carrier on the boat transom and the support bracket, and steering cylinders between the support bracket and a cavitation plate on the drive shaft housing having engagement locations on the bracket, are situated in close proximity to each other.

Abstract: A boat propulsion unit intended to be suspended on the outside of a boat transom, comprises a propeller drive shaft housing, a suspension arrangement intended to be fixedly secured to the transom, and a pivot for the drive shaft housing to allow pivotal displacement of the drive shaft housing relative to the suspension arrangement about a pivot axis in a vertical plane and a pivot axis in a horizontal plane. A steering device effects pivotal displacement of the drive shaft housing about the first-mentioned axis, and trim and tilt structure effects pivotal displacement of the drive shaft housing about the second-mentioned axis.

Abstract: A boat propulsion unit adapted to be suspended on the outside of a boat transom and drivably connected to an engine on the inside of the transom. The unit comprises a propeller drive shaft housing, a suspension arrangement adapted to be fixedly secured to the transom, a pivot which pivotally connects the drive shaft housing to the suspension arrangement to allow pivotal displacement of the drive shaft housing relative to the suspension arrangement about a pivot axis in a vertical plane and pivot axis in a horizontal plane, a steering device which is arranged to effect pivotal displacement of the drive shaft housing about first-mentioned axis, and a trim and tilt device which is arranged to effect pivotal displacement of the drive shaft housing about the second-mentioned axis. The suspension arrangement (2) comprises a hollow frame member (5) which has a closed cross-sectional configuration and is adapted to be secured around an opening (12) in a boat transom (4).

Abstract: A propeller has a hub affixed to a propeller shaft so as to rotate therewith. The hub is axially locked by a locking arrangement consisting of a lock nut screwed on to the shaft and a lock screw screwed into the end of the shaft to lock the nut. The screw is tightened more than the nut in order to cause the thread on the nut to load the opposite thread flank on the shaft. A portion of the nut which is deformed during tightening of the screw holds the nut and screw together during subsequent removal of the propeller.

Abstract: A boat propulsion unit adapted to be suspended on the outside of a boat transom and drivably connected to an engine on the inside of the transom. This unit comprising a propeller drive shaft housing, a suspension arrangement adapted to be fixedly secured to the transom, a pivot which pivotally connects the drive shaft housing to the suspension arrangement to allow pivotal displacement of the drive shaft housing relative to the suspension arrangement about a pivot axis in a vertical plane and pivot axis in a horizontal plane, a steering device which is arranged to effect pivotal displacement of the drive shaft housing about the first-mentioned axis, and a trim and tilt device which is arranged to effect pivotal displacement of the drive shaft housing about the second-mentioned axis. The pivot comprises a first lower and a second upper universal joint (22, 24 resp.

Abstract: Boat propulsion unit comprising a suspension arrangement (2) and a propeller drive shaft housing (3) which, via a lower and an upper universal joint (22, 24, respectively), are pivotally connected to each other. The suspension arrangement comprises a frame (5) in the form of an extruded aluminum profile which is fixed around an opening in a boat transom, and a carrier (6) attached to the frame member, the carrier covering the opening and supporting the pivot connection. The carrier is integrally formed with a flywheel casing (20) for a connected engine.

Abstract: An outboard boat propeller drive unit with an anti-cavitation plate (6) above the propeller or propellers (4,5) has an exhaust duct (7) extending through the anti-cavitation plate. The exhaust duct (7) has its outlet port (11) located on the underside of the anti-cavitation plate level with and just above the sweep "a" of the blade tips of the aft propeller.

Abstract: A double propeller arrangement for a marine propulsion unit, for example of the type which includes a so-called stern-drive. Each propeller has a hub consisting of an inner sleeve with splines for attachment to a propeller shaft, an outer sleeve with propeller blades, and an elastic bushing between the sleeves. Particular to the propeller arrangement is that the inner sleeve of respective propeller hubs is provided with an axial passage for the discharge of exhaust gases from an internal combustion engine connected to the propeller drive.

Abstract: Boat propulsion unit comprising a suspension arrangement (2) and a propeller drive shaft housing (3) which, via a lower and an upper universal joint (22, 24 resp.), are pivotally connected to each other. The lower joint has a ball (25) which is attached to the drive shaft housing. The ball is provided with a through-passage (29) which communicates with a cooling water inlet (31) in the drive shaft housing and an outlet (46) for connection to the cooling water intake of the engine.

Abstract: Boat propulsion unit, comprising two outboard Propeller drives (3,4), having anti-cavitation plates (7), which are coupled to each other via a tie-bar (10) with a wing profile. In the trim position of the stern drive for low speed, the wing profile has an angle of attack in order to exert a lifting force on the stern drives under the influence of the water flowing past it.

Abstract: Boat propulsion unit comprising a suspension arrangement (2) and a propeller drive shaft housing (3) which, via a lower and an upper universal joint (22, 24 resp.), are pivotally connected to each other. The suspension arrangement comprises a hollow frame member (5) made from extruded aluminum and arranged around an opening in a boat transom. The frame member presents, in cross-section, a T-shaped slot (13), in which a plurality of screws (14) are accommodated. With the help of nuts (16) and intermediate yokes (15) on the inside of the transom, the screws hold a flange on the frame member against a surface on the outside of the transom in order to secure the frame member.

Abstract: Boat propulsion unit comprising a suspension arrangement (2) and a propeller drive shaft housing (3) which, via a lower and an upper universal joint (22, 24 resp.), are pivotally connected to each other. A hydraulic piston-cylinder arrangement (35) has its cylinder connected to the upper joint and, at the lower end of its piston rod, presents a forked bracket (39) which is pivotally connected to an upper region of the drive shaft housing. At a distance from the upper joint (24), the cylinder (34) of the arrangement presents attachments for a steering mechanism, by means of which the arrangement is displaceable about a vertical axis (a). The embodiment implies that the piston-cylinder arrangement serves both as a trim and tilt cylinder as well as a rudder.

Abstract: An exhaust muffler for marine engines with two rows of cylinders, especially V-engines. The exhaust muffler comprises a horizontal cylindrical container (20) mounted transverse to the rows of cylinders and having an exhaust inlet (26) and an exhaust outlet (27) for each row of cylinders. The container is mounted between the rear of the engine (1) and the boat transom (3).

Abstract: A shock absorber for absorbing external momentary steering forces acting on a steerable stern drive for boats. The shock absorber (11) is a hydraulic piston-cylinder device which is articulated between the anti-cavitation plate (9) of the drive (3) and a fixed portion (4) of the boat.

Abstract: An exhaust muffler for marine engines comprises a cylindrical container arranged to be mounted with its longitudinal axis horizontal and traverse to the longitudinal axis of the engine. The container forms an expansion chamber, which is closed at one or both ends by an end piece (23) depending of whether it is used on engines with one or two rows of cylinders. The end piece has an inlet (26) and an outlet (27) for exhaust gas and intermediate flow diverting baffles (50,51).

Abstract: A boat-propeller unit comprises a carrier (4), a propeller-leg (5) and a sensor (13) which senses the angle of the propeller-leg relative to the carrier and which is intended for connection to an electrical indicating instrument mounted on the instrument panel of the boat. The sensor is of the kind which produces an output signal which varies as the distance of the sensor from an object and which is located centrally of a surface (11) on the propeller-leg, the distance of which from the sensor varies with changes in the angle of the propeller-leg relative to the carrier.