Abstract: An improved hydraulic system for a twin propeller marine propulsion unit. A vertical drive shaft is operably connected to the engine of the propulsion unit and carries a pinion that drives a pair of coaxial bevel gears. An inner propeller shaft and an outer propeller shaft are mounted concentrically in the lower torpedo section of the gear case and each propeller shaft carries a propeller. To provide forward movement for the watercraft, a sliding clutch is moved in one direction to operably connect the first of the bevel gears with the inner propeller shaft to drive the rear propeller. A hydraulically operated multi-disc clutch is actuated when engine speed reaches a pre-selected elevated value to operably connect the second of the bevel gears to the outer propeller shaft, to thereby drive the second propeller in the opposite direction.

Abstract: A maneuvering control system is provided which utilizes pressurized liquid at three or more positions of a marine vessel in order to selectively create thrust that moves the marine vessel into desired locations and according to chosen movements. A source of pressurized liquid, such as a pump or a jet pump propulsion system, is connected to a plurality of distribution conduits which, in turn, are connected to a plurality of outlet conduits. The outlet conduits are mounted to the hull of the vessel and direct streams of liquid away from the vessel for purposes of creating thrusts which move the vessel as desired. A liquid distribution controller is provided which enables a vessel operator to use a joystick to selectively compress and dilate the distribution conduits to orchestrate the streams of water in a manner which will maneuver the marine vessel as desired.

Abstract: An improved hydraulic system for a twin propeller marine propulsion unit. A vertical drive shaft is operably connected to the engine of the propulsion unit and carries a pinion that drives a pair of coaxial bevel gears. An inner propeller shaft and an outer propeller shaft are mounted concentrically in the lower torpedo section of the gear case and each propeller shaft carries a propeller. To provide forward movement for the watercraft, a sliding clutch is moved in one direction to operably connect the first of the bevel gears with the inner propeller shaft to drive the rear propeller. A hydraulically operated multi-disc clutch is actuated when engine speed reaches a pre-selected elevated value to operably connect the second of the bevel gears to the outer propeller shaft, to thereby drive the second propeller in the opposite direction.

Abstract: A skeg assembly for a marine propulsion unit includes a generally U-shaped saddle that is removably attached to the lower torpedo section of the gearcase of the propulsion unit, and a thin wedge-shaped skeg extends downwardly from the saddle. During planing conditions of the boat, the water line is slightly below the lower torpedo section so that the saddle is out of the water. The side surfaces of the skeg having opposed water intake openings each of which is bordered rearwardly by a laterally projecting shoulder that terminates in a sharp vertical edge and the intake openings are bordered forwardly by a curved surface that connects the side surfaces of the skeg. The water intake openings communicate with a water passage in the skeg which, in turn, communicates with a water passage in the torpedo section so that water can be delivered to the cooling system of the propulsion unit.

Abstract: A twin propeller marine propulsion unit for a watercraft. A vertical drive shaft operably connected to the engine is journaled for rotation in a lower gear case and carries a beveled pinion that drives a pair of coaxial bevel gears. An inner propeller shaft and an outer propeller shaft are mounted concentrically in the lower torpedo-shaped section of the gear case and each propeller shaft carries a propeller. To provide forward movement for the watercraft, a sliding clutch, is moved in one direction to operably connect a first of the bevel gears with the inner propeller shaft to thereby drive the rear propeller. When the engine speed reaches a pre-selected elevated value, a hydraulically operated multi-disc clutch is actuated to operably connect the second of the bevel gears to the outer propeller shaft, to thereby drive the second propeller in the opposite direction.

Abstract: In a Vee bottom planing boat running chines dry at top speed, running trim angle is increased by reducing wetted planing surface area by removing wetted planing surface at areas of least dynamic pressure and by shifting a portion of the trailing edge of the wetted planing surface forwardly, in combination, until running trim angle is slightly less than porpoising trim angle and such that the boat can be made to porpoise by trimming the drive when the boat is running at 70% to 100% of top speed.

Abstract: A marine drive (10) has two counter-rotating surface operating propellers (12 and 14). The drive has a vertical X-dimension (254) in the range of about 13 inches to 19 inches in combination with a shaft-spacing dimension (258) in the range of about 8 inches to 15 inches in combination with a surfacing dimension .gtoreq. zero. In one embodiment, the shaft-spacing dimension is 13.5 inches, the vertical X-dimension is 16 inches, and the surfacing dimension is 2 inches.

Abstract: A marine trolling propulsion system (2) has a lower submerged housing (4) including an electric motor (5) driving a propeller (6) through a reducing traction drive provided by rolling contact of threee balls (57-59) between split inner races (36 and 38) and an outer race (60) to drive a transfer member (68) which rotates the propeller (6). The inner race halves (36 and 38) are axially loaded by Belleville washers (72) providing constant axial force with axial deflection, and a limited maximum loading force capability to intentionally provide overload slip protection. The inner race halves (36 and 38) are keyed to the intermediate floating shaft (14) on raised hexagonal shoulders (32 and 34) permitting rocking of the inner race halves (36 and 38) and self-seating and alignment of the inner race halves to the balls (57-59).

Abstract: An electric trolling motor includes a lower unit with a cylindrical motor housing closed at the aft end by a planetary gear-reduction subassembly including a cup-shaped end bell housing. A motor shaft hub member telescopes into the housing and clamps against an annular gear with clamping bolts passing therethrough and threaded into the hub member. Planetary gears carried by a cage engage the annulus gear. A propeller shaft is fixed to the cage and journaled in a hub portion of the housing. A sun gear meshes with the planetary gears and has an opening aligned with an opening in a hub portion of the hub member to receive the motor shaft. The shaft openings in the gear housing and in the hub member have shaft bearings in spherical seats and rotating seals. The subassembly drops onto the motor shaft with the gear housing abutting the motor housing and secured thereto by bolts. The motor shaft and sun gear have complementing interlocking surfaces to establish rotatable interconnection.

Abstract: A pivotal mount for a trolling motor includes a deck bracket having a housing arm pivotally mounted at one end. A gear mechanism within the arm has a fixed bevel gear on the pivot arm axis meshing with a bevel gear on a rotatable torque tube. A drive bevel gear is secured to the opposite end and meshes with a gear sector on a coupling head pivotally mounted in the outer end of the arm. The head includes a swivel support within which the trolling motor unit is rotatably mounted. The coupling head and motor unit are located between a depending propulsion position and transport position in response to the 180.degree. swinging of the pivot arm. The torque tube is coupled to the bevel gears by sliding couplings and is coupled to a locking device for the arm and for the gear sector to lock them in the propulsion position and simultaneously release them for raising to the transport position.