Abstract: A jet propulsion system for watercraft employs twin impellers contained within a common housing assembly. The housing assembly defines an intake duct that delivers water from a single water inlet opening to impellers supported within the housing. The inlet opining can be positioned centrally on the watercraft to avoid drawing air in during abrupt maneuvering. A dividing wall extends from a location forward of the impellers into the water inlet duct to divide the flow of water well upstream of the impellers. The dividing wall is configured to reduce cross-effects caused of the counter-rotating impellers in the water flow upstream of the impellers without requiring any substantial change in direction of the water flow from the water inlet opening to the impellers.

Abstract: Simplified propelling system for a propeller-supporting shaft of adjustable inclination, where the front end of the propeller-supporting shaft is carried by a hollow cylindrical body steadily fixed to the reversing gearbox, which in turn is steadily fixed to the engine.The hollow cylindrical body comes out of the stern surface of the boat through a hole sealed by rubber rings which allow small angle adjustments to modify the inclination of the propeller-supporting shaft, further carried by an adjustable support placed outside the boat; the inclination of the propeller-supporting shaft is modified by raising or by lowering a single assembly including the engine, the reversing gearbox, the hollow cylindrical body and the propeller-supporting shaft.

Abstract: A sealing assembly for a rotary drive shaft that extends through the hull of a boat, the outboard end of the shaft being coupled to a propeller and the inboard end to a marine engine for rotating the propeller. The assembly includes a cylindrical housing joined by a flexible hose to a tube in the stern of the boat through which the shaft passes. Received within the housing is an annular bearing whose bore diameter depends on the size of the shaft whereby the bearing installed in the housing has an internal diameter appropriate to the size of the shaft being sealed by the assembly. Coupled to one end of the housing is an annular cap having an elastomeric lip seal therein that frictionally engages the shaft to prevent sea water from leaking into the boat. A reservoir defined by an annular space within the housing between the lip seal and the bearing is continuously fed with water to cool and lubricate the lip seal.

Abstract: An intermediate bearing assembly that is mountable on a pedestal of a marine vessel that incorporates an integrated alignment system. In particular, the bearing assembly includes a housing for receiving a portion of a shaft; and a lifting and lowering system attached between the housing and the pedestal for providing a concentrated applied force at approximately the center vertical axis of the housing. The lifting and lowering system includes four hydraulic jacks located equidistant from the center vertical axis of the housing. Hydraulic pressure is related through the area of the jack cylinders to radial force. As a result, when a predetermined jacking force is achieved, the correct radial force loading on the bearing is attained. Each of the jacks is free to seek a position of extension independent of the others. The jacks are then locked into a secure hold position to maintain the shaft in alignment.

Abstract: Briefly stated, the present invention comprises a seal joint for a propeller shaft passing through a boat hull. The seal includes a bronze support bushing that is fitted over the propeller shaft, first elastic rings cooperating with the support bushing, an elastic bellows surrounding the shaft downstream of the support bushing, and a lubricating oil circulation system. The lubricating oil circulation system comprises two stages that cooperate to establish water tightness, a first ring-shaped water retention chamber filled with a viscous insoluble sealing medium, and a second chamber filled with lubricating oil. Forced, closed-circuit, circulation of the lubricating oil is produced during rotation of the propeller shaft within the support bushing, inside a static eccentric chamber formed within the support bushing, the support bushing being loosely fit onto the propeller shaft with no rigid fixing so that the propelled shaft is rotatable and axially moveable.

Abstract: A number of embodiments of outboard motors having power head and drive configurations that permit the engine to be mounted so that its crankshaft is offset from the drive shaft so as to facilitate larger turning angles without interference.

Abstract: An impeller mounting system for a jet propelled watercraft uses an impeller shaft having a tapered portion and an impeller hub having a coaxial opening with a corresponding tapered seat. The impeller hub is tightened onto the impeller shaft so that the tapered portion of the impeller shaft presses against the tapered seat of the coaxial opening in the impeller hub with sufficient force to prevent the impeller hub from slipping with respect to the impeller shaft when the impeller shaft rotates to drive the impeller hub. Static frictional forces between the tapered surfaces bear the entire rotational load for the jet drive, therefore reducing chatter noise and wear which can be caused by load bearing splines or the like. The tapered seat configuration virtually assures proper concentric alignment of the impeller within the wear ring. The impeller shaft also preferably includes a bearing support portion extending rearward from the coaxial opening in the hub.

Abstract: An elastic plane-bearing support for the impeller shaft of a water jet propulsion unit for providing good support and yet accommodating relative movement between the engine and the jet propulsion unit.

Abstract: A drive unit for a boat having an engine with a flywheel surrounded by a flywheel casing, a propeller drive housing connected to, but electrically insulated from, the flywheel casing, and an input shaft for the propeller drive housing which is driven and electrically insulated from the flywheel.

Abstract: This invention relates to a marine jet drive having improved operation, especially in regard to having efficient adaptation to propulsion engine and hull design; having a drive shaft with flexible coupling at each end, internal to the jet drive; having through-the-nozzle engine exhaust; having simplified, combined means of steering and reversing; having controllable nozzle aperture and trim control; having combination reverse flow deflector and trim plane; having means to disengage the engine from the jet to obtain true neutral; having protection from and removal of debris in the water intake duct; generally having fewer overhauls, easier serviceability and lighter weight.

Abstract: A jet propelled watercraft has a coupling assembly to couple an engine crankshaft to a jet pump impeller shaft. The coupling assembly can accommodate substantial engine crankshaft vibrations, yet effectively isolates the jet pump impeller shaft from transverse movement. The coupling assembly includes an engine crankshaft coupling head, an intermediate coupler, an impeller shaft coupling head, and two elastomeric isolators positioned between each of the coupling heads and the intermediate coupler. The intermediate coupler is supported exclusively by the elastomeric isolators, and is allowed to tilt transverse to the rotational axis of the intermediate coupler to accommodate engine crankshaft displacement. The coupling assembly is practical for personal watercraft because, although elastomeric isolators wear or shred quickly in the presence of transverse misalignment, elastomeric isolators provide significant durability in the presence of a reasonable amount of angular displacement.

Abstract: A transmission for a marine outboard drive includes a compact bearing arrangement to provide an increased flow area for exhaust discharge behind the transmission with a lower unit of the drive. The bearing arrangement also improves the stability of a supported propulsion shaft. The bearing arrangement includes a first bearing assembly which supports the propulsion shaft at a point corresponding with the axial location at which a driving clutch is coupled to the shaft. The clutch selectively engages a driven gear of the transmission to drive the propulsion shaft. A thrust flange on the propulsion shaft desirably is positioned between the first bearing assembly and a second bearing assembly which journals the driven gear.

Abstract: A bearing carrier and ring nut of a marine outboard drive both attach to a lower unit of the drive by rotating them in the same direction. The bearing carrier includes a threaded front end which screws into a threaded aperture within the lower unit. A ring nut locks the bearing carrier in place by screwing into a hole on the rear face of the lower unit. A locking tab washer desirably locks the ring nut in place. Because the threads on the bearing carrier and the ring nut are of the same hand, the ring nut does not loosen the bearing carrier when threaded into the hole of the lower unit rear face.

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: A system to adjust to the changing draft of ocean-going ships on the aft seal system equipped with several outwardly-directed gaskets and one inwardly-directed gasket, in which, between each two outwardly-directed gaskets a ring-shaped chamber is reserved, to which a feed line for compressed air is connected. Integrated into the feed line is a pressure control mechanism and a discharge channel which can periodically empty into the interior of the ship (bilge), whereby the pressure in the ring-shaped chamber is always maintained slightly below the outside water pressure. The system is characterized by the fact that an electronic draft measurement system is located on the ship's hull to supply electric signals which correspond to the current draft, which signals actuate the pressure control mechanism.

Abstract: Propulsion unit for marine vessels with a gear or bearing housing (6) in which a propeller shaft (7) with a surface-breaking propeller (8) is carried. In a horizontal plane the propeller shaft forms an angle (.alpha.) to a guide fin (9) so as to create a resultant force (R) of the pressure force (P) of the propeller and the side force (S), with the resultant force being aligned with the longitudinal direction (C.sub.L) when the vessel is travelling straight ahead.

Abstract: A corrosion-resistant high-strength drive connection between a coupling element and a shaft that is supported in an anti-friction bearing. The shaft has a direct splined connection with the coupling element and is encircled by a corrosion-resistant sleeve that has an inter-fitting relationship with the coupling element to protect the spline from corrosion.

Abstract: A three-stage coupling has a driven input element and an output element adapted to be drive to a load and coaxial with the input element. The third stage has an annular input side and fixed to the input element, an annular output side adjacent and coaxial with the input side, and a relatively soft elastomeric ring secured between the input and output sides. The third stage defines a cavity on the axis and has ends defining axially spaced end planes perpendicular to the axis. The second stage is substantially received in the cavity between the planes and has an output side and fixed to the output element, an input side adjacent the second-stage output side and fixed to the third-stage output side, and a relatively hard and elastomeric body between the second-stage input and output sides.

Abstract: A device to discourage theft of stern drives of power boat inboard-outboard propulsion units comprises a locking collar installed about the drive shaft at a location between the engine and the transom of the boat to prevent withdrawal of the drive shaft through the transom passage.

Abstract: A monolithic metallic drive shaft for a marine propulsion device is disclosed which is resistant to corrosion. The drive shaft comprises proximal and distal end portions, each of which has a predetermined surface hardness. The surface hardness of one of the proximal and distal end portions is greater than the surface hardness of the other of the proximal and distal end portions.

Abstract: A drive transmission system for a vessel propelling equipment 1 provided with a clutch operating device that can easily be installed comprises a shift slider 40 axially slidable within a propeller shaft 9 to move a clutch gear 30 through a clutch shifter pin 38 inserted through the propeller shaft; and an operating member capable of operating the shifts slider from above a gear case 5; the operating member includes: a shift fork 50 engaged with 9 fork engaging portion 35c of the shift slider, to move the shift slider; a guide member 59 supporting the shift fork movable in a specific direction; a rotary rod member 55 engaged with a rod engaging section 50b of the shift fork to move the shift fork; and a support member 51 drivably supporting the rod member and fixedly supporting the guide member, thereby sub-assembling the rod member and the guide member to transmit the operation of the rod member to the shift fork; the shift fork is so assembled to be engaged with the fork engaging section of the shift slider

Abstract: A device is provided for isolating a shift shaft extending through an exhaust passage of a bell housing in a marine drive system. The device includes an elongated sleeve for receiving the shift shaft therein. The sleeve has a first portion sealably mounted in a first bore extending through the top wall of the exhaust passage and a second portion sealably mounted in a second bore which extends through the bottom wall of the exhaust passage. The elongated sleeve prevents galvanic corrosion and erosion of the aluminum housing and the stainless steel shaft.

Abstract: Disclosed herein is a shaft assembly including a vertically extending axis and comprising a lower shaft having an upper end portion including an upper end, and an axial bore extending downwardly from the upper end, an upper shaft including a lower end portion received in the axial bore and including a lower end and an outer surface extending axially from the lower end, means on the outer end portions of the upper and lower shafts for preventing rotary movement therebetween, and means for selectively permitting assembly and disassembly of the upper and lower shafts and for preventing disassembly of the upper and lower shafts comprising an annular groove in the axial bore in the lower shaft, an inclined bore located in the end portion of the upper shaft, extending upwardly at an acute angle to the axis, and having an opening located wholly in the outer surface, and a ball movable in the inclined bore and in the annular groove between a locked position wherein, when the axis is vertical, the ball is partially lo

Abstract: A propulsion system for water vessels comprises a rotor located at the rear end of the vessel body, which rotor rotates inside a shroud to generate a propulsion force, and a stator located behind the rotor for recovering the rotation energy created by the rotor. An unexpected high noise reduction is accomplished because the rotor is mounted on a hollow drive shaft, through which an axle extends which is fixed to the body of the vessel, and which axle support the stator and the shroud that surrounds the rotor, without further supporting devices.

Abstract: An adapter for interconnecting a marine engine to a stern drive includes an adapter ring having a pair of concentric flanges with bolt-receiving apertures formed in each of the flanges. The outermost flange is secured to the flywheel end of the engine. A coupler housing is secured to the flywheel end of the engine radially inwardly of the innermost flange of the adapter ring and houses a coupler having an internally splined rotatable part, and a bell housing having a radially outwardly extending flange is secured to the innermost flange of the adapter ring in housing relation to the coupler housing. A trailing end of the bell housing is secured to a transom housing which is centrally apertured to admit an externally splined stern drive rod to engage the rotatable, internally splined part of the coupler.

Abstract: Two embodiments of balancer arrangements for internal combustion engines particularly adapted for use in outboard motors. In each embodiment, the balancer shaft is journalled within the crankcase chamber of the engine and is driven from the crankcase from a point between its ends. Single and twin balancer shaft arrangements are disclosed.

Abstract: An acoustic isolation structure providing an acoustically isolated opening nd comprising coaxial inner and outer annular structural members defining an irregular annulus between them. Acoustical isolation material is provided within this annulus to acoustically uncouple the two members. Radially overlapping structural rings extending from the members into the annulus limit lateral movement of the inner member and preserve the generally coaxial relation of the members.

Abstract: A rescue device for a helicopter, the rescue device, being removably attached to the helicopter and including a basket-like structure, the front portion of which extends beyond the forwardmost portion of the helicopter.

Abstract: A ship, in particular a deep-draft vessel configured for travel on the oceans or great lakes, can have a hull with two concentrically rotating propeller shafts passing through the hull, and rotate in opposite directions to one another. The ship will generally have seals between the propeller shafts, and between the propeller shafts and the hull. In general, it is necessary to lubricate and cool the sealing surfaces of the individual seals, so that the useful life of the individual seals is prolonged, and the risk of failure of the seals is reduced. For the effective lubrication of highly-stressed seals of propeller drive systems for ships with two concentric propellers rotating in opposite directions, a forced feed lubrication system with circulating lubricating oil has been found to be advantageous.

Abstract: A device for setting the propulsion means of a watercraft in an arbitrary angular position within the perimeters of an imaginary conical configuration with one end of the propulsion means attached to an apex of the cone. The device comprises a first sleeve which is arranged for rotational movement about an axis which intersects the apex of the cone. The sleeve is formed with an angular portion. A second sleeve is arranged for rotating movement about the angular portion. A propulsion shaft extends through the sleeve, from the apex of the cone and exteriorly of the sleeve in a direction at an angle to the rotational axis of the sleeve, the axis likewise intersecting the apex of the cone.

Abstract: A water-jet drive with a stator and a rotor enclosed by a housing having an inlet and an outlet nozzle, the rotor shaft which supports the rotor at one end and has torque-transmitting means at the other end being rotatably supported in the housing by shaft bearings arranged upstream and downstreams. A shaft bearing associated with the torque-transmitting means and supporting the rotor shaft is constructed so as to enable an axial displacement of the rotor shaft which can be adjusted via an external adjusting member.

Abstract: A marine stern drive has an engine output coupler driven to rotate about an axis with a hub that has an axial opening. The forward end of the axial opening is splined and the rearward end is non-splined. The axial opening receives an output driveshaft. The forward end of the driveshaft is splined and engages the splined section of the axial opening so that the engine coupler can rotatably drive the driveshaft. An O-ring seal is provided between the driveshaft and the axial opening in the non-splined section of the axial opening towards the rearward end of the axial opening. An end plug is provided in the forward end of the axial opening for plugging the forward end of the axial opening. A grease passage is provided through the engine coupler to allow grease to be introduced between the seal and the end plug and lubricate the splines. The space between the end plug and the drive plug acts as a grease reservoir. A hole is provided through the end plug to relieve grease pressure and reduce hydraulic lock.

Abstract: A boat propelling assembly includes a single support unit which includes a thrust articulation and horizontal and vertical movement members controlled by a horizontal actuation element. Manual or automatic inclination control is also provided by a control system to determine the inclination of the propelling member to which the propeller is engaged, so as to keep the propeller totally or partially submerged.

Abstract: A marine propulsion device including a lower unit, a propeller shaft rotatably supported by the lower unit and to support a propeller, the shaft including a longitudinal axis and a surface defining a plane which is substantially normal to the axis, and a thrust washer for transmitting thrusting force from the propeller to the surface.

Abstract: A marine propeller with break away hub has an insert cavity with pentagonal cross section extending coaxially with the axis of rotation of the propeller, along at least a portion of the length of the propeller. A resilient insert corresponding to the insert cavity is positioned in the insert cavity. The insert is sized for slip fit with the cavity and is adapted for connection with a propeller drive shaft. Preferably, the insert has a cylindrical aperture with a series of grooves disposed circumferentially thereabout extending coaxially through the insert and the insert is connected with the propeller shaft through a shaft sleeve. The shaft sleeve corresponds to the aperture in the insert, has a cylindrical outer surface with a series of teeth disposed circumferentially thereabout, and has a mounting aperture extending coaxially through the shaft sleeve. The shaft sleeve is sized for hand force slip fit engagement with the insert.

Abstract: A coupling is provided for releasably joining two abutting sections of a drive shaft such as used to drive an inboard power boat. An inner sleeve within the coupling is replaceable and permits one shaft to rotate relative to the other within the coupling if a predetermined torque setting is exceeded without damaging the coupling. The torque "breakaway" point for the coupling can be adjusted by tightening or loosening the bolts connecting the two halves of the coupling around the shafts.

Abstract: An outboard motor comprising an engine, a propeller shaft, a first drive shaft portion defining an axis and having a first end connected to the engine, and a second end opposite the first end, a second drive shaft portion coaxially aligned with the first drive shaft portion, having a first end connected to the propeller shaft, and a second end opposite the first end of the second drive shaft portion and telescopically connected to the second end of the first drive shaft portion, a device for preventing relative rotation between the first and second drive shaft portions about the axis, and a device for securing the first drive shaft portion to the second drive shaft portion.

Abstract: The present invention relates to a regulating device which permits changing inclination angle of the shaft line of a propeller and comprises an at least partially spherical and revolving box containing the support bearings of the propeller shaft and two stands supporting the same propeller shaft and connected by slots and locking bolts.

Abstract: A relatively small and light weight personal watercraft includes a driveshaft tunnel which permits the driveshaft housing of a string trimmer apparatus to be installed therein. The string trimmer apparatus is modified by removing the string trimmer or other head which may be attached, installing a propeller(s) or impeller(s), removing any handles from the string trimmer, temporarily removing the power head so that driveshaft housing may be installed within the driveshaft tunnel of the watercraft, installing a fairing (if desired) and/or handlebars, and reattaching the throttle control to the handlebars. The modified string timmer may be used as both a power system for the watercraft and also provides directional control by turning the attached handlebars or fairing in order to rotate the power system about an axis concentric with the driveshaft and thereby change the direction of the thrust line of the propeller(s) or impeller(s).

Abstract: Apparatus for emergency enablement of a boat propeller. The apparatus comprises a central mounting plate having an aperture for engagement with one end of the propeller shaft to which the propeller is attached. A plurality of cantilevered members, the proximal ends of which are fixed at spaced intervals around the periphery of the central mounting plate, extend perpendicular to the mounting plate for disposal within longitudinal spaces of the boat propeller.

Abstract: A corrosion reducer for use with ships having a hull, a propeller mounted a propeller shaft and extending through the hull, bearings supporting the shaft, at least one thrust bearing and one seal. The improvement includes a current collector and a current reduction assembly for reducing the voltage between the hull and shaft in order to reduce corrosion due to electrolytic action. The current reduction assembly includes an electrical contact, the current collector, and the hull. The current reduction assembly further includes a device for sensing and measuring the voltage between the hull and the shaft and a device for applying a reverse voltage between the hull and the shaft so that the resulting voltage differential is from 0 to 0.05 volts. The current reduction assembly further includes a differential amplifier having a voltage differential between the hull and the shaft.

Abstract: A marine propulsion device comprising a housing adapted to be mounted on the transom of a boat and adapted to rotatably support a propeller, a drive shaft rotatably supported by the housing and adapted to be drivingly connected to the propeller, a bevel gear supported in coaxial relation to the drive shaft for rotation relative thereto, a clutch element fixed to the bevel gear for common rotation therewith, a bearing located between the bevel gear and the housing, and a bearing located between the clutch element and the drive shaft.

Abstract: The present invention relates briefly to a jet propulsion assembly for ships, the assembly including a propeller pump of an axial or a semiaxial type. The propeller pump has a pump housing (6), the inlet of which is connected to a water inlet channel and the outlet of which is connected to an outlet device. In the water flow channel through the pump housing a pump wheel (11) is rotably journalled in a stationary casing (8). A drive shaft (12) of the pump wheel (11) extends from a drive unit through the water inlet channel to the pump wheel (11). The pump wheel (11) and the drive shaft (12) are connected by a flexible coupling (13) which is essentially torsional resistant but permits angular deviations between the drive shaft (12) and the rotational shaft of the pump wheel (11).

Abstract: The invention comprises a steerable propeller unit for use in place of a steerable rudder and fixed propeller on watercraft employing inboard straight line propulsion systems. A coupler is fitted to the rear of the drive shaft projecting from the craft in place of a propeller. The coupler is affixed to a splined shaft which, in turn, is connected to a universal drive joint. A pivotable rudder shaft interconnects with the steering mechanism for the craft, and carries at its lower end a strut bearing. A short shaft connected to the universal joint extends through the strut bearing, and the propeller is affixed to the shaft behind the strut bearing. The propeller may thus be swung through an arc to either side of the center line of the craft by the steering mechanism. Top, bottom and side rudder plates may optionally be affixed to the strut bearing assembly.

Abstract: A marine drive (10) has a propeller (12) with a hub (14) mounted on a propeller shaft (22). A rear thrust hub (30) has one or more slots (40) spaced circumferentially around the propeller shaft. A nut (42) is threaded onto the propeller shaft to mount the propeller. A locking tab washer (60) around the propeller shaft between the nut and the propeller hub has one or more circumferentially spaced tabs (66) bendable forwardly into slots (40) of the rear thrust hub (30) and has ears (68) extending perpendicularly rearwardly from outer tips of the tabs externally of the slots. The ears may be gripped and pulled to bend the tabs rearwardly out of the slots, to enable removal of the nut, and hence removal of the propeller.

Abstract: An outboard motor lower unit construction including a bearing carrier that supports the propeller shaft and which extends into a cavity formed in the lower unit. The bearing carrier is held by a fasteners that is protected from extension into the body of water in which the watercraft associated with the outboard motor is operating so as to prevent turbulence. In some embodiments, the fasteners is covered by a cover plate and in other embodiments, the fasteners is protected by the hub of the associated propeller.

Abstract: A bidirectional thrust bearing system for the propeller shaft of a marine propulsion system includes a substantially circumferential groove milled into the propeller shaft. A pair of substantially semicircular force transferring members are adapted for placement within the groove, and front and rear bearing collars are placed adjacent the force transferring members. Front and rear needle bearings are provided adjacent the front and rear bearing collars, respectively. A front bearing adapter, interconnected with the walls of the cavity within which the propeller shaft is disposed, transfers forward thrust in the propeller shaft to the gearcase. A rear bearing carrier, held in position by means of a ring nut mounted within the cavity, serves to transfer rearward thrust in the propeller shaft to the gearcase.

Abstract: A pressure control system for stern tube seals includes at least two resilient radial lip-type seal rings held so as to surround a propeller shaft linear. The closest seal ring lip to the propeller is arranged to face outboard and the other adjacent seal rings' lips are arranged to face suitable directions so as to form annular chambers. The aft annular chamber located most closely to the propeller serves as a chamber having a fixed differencial pressure higher than the seawater pressure. The closest seal ring to the propeller is lifted, thereby allowing air to be bled into seawater and preventing the ingress thereof. A regulator unit which is capable of instantly ascertaining changes in the hull's draft is provided in an air-supplying mechanism communicating with the aft annular chamber, so as to maintain the air pressure therein higher than the seawater pressure by a constant differential pressure.

Abstract: An improved surface drive for a marine craft having an inboard engine in which propeller generated thrust forces are transferred directly and co-linearly from the propeller shaft, through a constant velocity U-joint to the engine or transmission shaft to thereby reduce the overall dimensions of the surface drive unit.

Abstract: A marine outboard drive and more particularly to two embodiments of improved transmission and propeller shaft thrust taking arrangements for the lower unit. In each embodiment, the forward and reverse driving thrusts are transmitted independently to the lower unit housing. In one embodiment, a single thrust flange transmits the thrust from the propeller shaft to both of the thrust bearings and in the other embodiment, the thrust is transmitted to the thrust bearings on opposite sides of the forward, reverse transmission for axially separating the driving thrusts from each other.