Abstract: An axial-flow outboard water jet propulsion unit is designed so that it does not extend below the bottom of the boat hull, but rather is disposed directly behind the hull transom. This is achieved by arranging the impeller shaft generally perpendicular to a generally vertical drive shaft, and by installing the impeller in a flow-through duct which, although placed directly behind the transom, has an inlet for taking in water located directly below the impeller shaft. The duct does not extend to a depth lower than the lowest point of the hull bottom. The impeller shaft penetrates the duct wall, while the impeller itself is rotatable inside the duct. The impeller impels water rearward toward a convergent exit nozzle of the duct, sucking in water through the duct intake. The aft opening of the exit nozzle forms the duct discharge outlet.

Abstract: An axial-flow outboard water jet propulsion unit is designed so that it does not extend below the bottom of the boat hull, but rather is disposed directly behind the hull transom. This is achieved by arranging the impeller shaft generally perpendicular to a generally vertical drive shaft, and by installing the impeller in a flow-through duct which, although placed directly behind the transom, has an inlet for taking in water located directly below the impeller shaft. The duct does not extend to a depth lower than the lowest point of the hull bottom. The impeller shaft penetrates the duct wall, while the impeller itself is rotatable inside the duct. The impeller impels water rearward toward a convergent exit nozzle of the duct, sucking in water through the duct intake. The aft opening of the exit nozzle forms the duct discharge outlet.

Abstract: A modular pontoon boat including a modular deck and modular pontoons is described. The modular deck includes interlocking portions. Each modular pontoon includes interlocking sections having locks and keys. The modular pontoon boat enables the length of the boat to be selected at the time of assembly, rather than fabrication.

Abstract: A modular boat hull including bow and stern sections and at least one center section. Preferably these modular sections are rotomolded thermoplastic parts. These modular hull sections can be quickly assembled by coupling a center section to the bow section and then coupling the stern section to the center section. To increase the length of the hull, additional hull center sections can be added as desired. The modular hull sections are coupled by locking arrangements and then secured by installing a support member which bridges the joints between the gunwale sections of adjacent hull sections. Each modular hull section has a lattice for supporting a deck. The deck can be a single piece installed inside the assembled hull. Alternatively, the deck may be modular.

Abstract: A water jet apparatus for propelling a boat. The water jet apparatus has a mechanism for adjusting the size of the outlet of the exit nozzle. The size of the outlet is increased to provide initial thrust and decreased for high speed. A smaller opening is also desirable for low-speed maneuvering. A cone made of resilient material is mounted to the stator hub. A hydraulically driven piston causes the resilient cone to elongate. This changes the shape of the cone and the position of the cone in relation to the exit nozzle outlet. When the resilient cone is elongated, the area of the exit nozzle outlet is decreased.

Abstract: A water jet apparatus with counter-rotating impellers for propelling a boat. The impellers are coupled by an assembly comprising an impeller shaft secured to a first impeller and a gear train coupling the impeller shaft to a second impeller for counter-rotation. Preferably the gear train comprises one beveled gear secured to the impeller shaft, another beveled gear secured to the second impeller, and a beveled pinion meshed with the first and second beveled gears. The counter-rotating impellers can be driven by a drive shaft coupled to the first impeller for boats having an inboard motor or by a drive shaft coupled to the pinion for boats having an outboard motor.

Abstract: A boat or other water craft having an inboard engine, an outboard pump jet apparatus and a transom plate on which the pump jet apparatus is pivotably mounted. The boat hull bottom has a water tunnel formed therein, the transom plate has a tube portion in flow communication with the water tunnel, and the pump jet apparatus has an inlet which, in the operating position of the pump jet, is in flow communication with the tube portion of the transom plate. The pump jet apparatus is selectively pivotable between an operating position and a service position. In the service position the pump jet inlet is accessible to a boat occupant to clear debris from the pump jet inlet.

Abstract: A modular pontoon boat including a modular deck and modular pontoons is described. The modular deck includes interlocking portions. Each modular pontoon includes interlocking sections having locks and keys. The modular pontoon boat enables the length of the boat to be selected at the time of assembly, rather than fabrication.

Abstract: A water jet apparatus having a mechanism for providing additional lateral thrust when a boat is moving in reverse. A steering nozzle is pivotably mounted at and in flow communication with the outlet of a flow-through housing, and has a pair of opposing side thrust nozzles. The water flow exiting the steering nozzle is reversed by a reverse gate which covers the main outlet of the steering nozzle and by a reverse nozzle incorporated as part of the steering nozzle. The reversed flow exits the steering nozzle via the reverse nozzle, which directs the reversed flow forward and downward. When the steering nozzle is turned a predetermined angle to one side in reverse, the side thrust nozzle on the opposing side is swung into the path of water flow exiting the housing outlet.

Abstract: A simple and efficient reverse propulsion and control means for water jet powered boats which includes a sliding water valve for controlling exhaust thrusters mounted around the peripheral of the boat and which is coordinated with pivotal movement of the main thruster nozzle.

Abstract: Disclosed herein is a one piece drive shaft housing comprising a casting including an outer surface having an upper end surface, a lower end surface, and an endless side surface extending between the upper and lower end surfaces, an internal cavity extending between the upper and lower end surfaces and adapted to receive a drive shaft and a clutch operated linkage, an internal exhaust gas passage extending between the upper and lower end surfaces and located in spaced relation to the cavity, an internal coolant supply passage extending between the upper and lower end surfaces, an internal idle exhaust passage including a series of expansion chambers and extending between the upper end surface and the endless side surface, and an internal coolant drainage passage extending between the upper and lower end surfaces in heat exchanging relation to the exhaust gas passage.

Abstract: Disclosed herein is marine apparatus comprising a boat including a hull, an outboard motor including a propulsion unit having a rear side and mounted on the hull for pivotal movement relative thereto between a trimmed-in position, a tilted-up position, and a trimmed-out position between the trimmed-in position and the tilted-up position, a cover which extends above the propulsion unit and which is mounted on the hull for movement relative thereto about an axis located forwardly of the rear side of the propulsion unit and between a lower position wherein the cover affords movement of the propulsion unit between the trimmed-in position and the trimmed-out position, and an upper position wherein the cover affords movement of the propulsion unit to the tilted-up position, and engaging surfaces on the motor and on the cover for moving the cover from the lower position to the upper position in response to movement of the propulsion unit from the trimmed-out position to the tilted-up position.

Abstract: Disclosed herein is a one piece drive shaft housing comprising a casting including an outer surface having an upper end surface, a lower end surface, and an endless side surface extending between the upper and lower end surfaces, an internal cavity extending between the upper and lower end surfaces and adapted to receive a drive shaft and a clutch operated linkage, an internal exhaust gas passage extending between the upper and lower end surfaces and located in spaced relation to the cavity, an internal coolant supply passage extending between the upper and lower end surfaces, an internal idle exhaust passage including a series of expansion chambers and extending between the upper end surface and the endless side surface, and an internal coolant drainage passage extending between the upper and lower end surfaces in heat exchanging relation to the exhaust gas passage.

Abstract: A marine propulsion unit is disclosed which has an exteriorly accessible clean-out capability. The unit has an impeller housing located outside of the transom of a marine craft in which the unit is installed, which impeller housing has a separable portion that permits access to the main passage including the impeller when separated. The design also permits insertion of a hose connected fitting for backflushing the cooling system of the power head of the unit.

Abstract: A mounting system for connecting a marine power head having a vertically disposed crankshaft to a jet propulsion unit for isolating operational vibrations includes an adaptor plate, a power head mounting apparatus on the adaptor plate for securing the power head to the plate, and a connecting assembly for connecting the adaptor plate to the jet propulsion unit at at least one point, the connecting assembly including resilient portions to isolate vibrations generated by the power head.

Abstract: A system for mounting a jet propulsion unit to a watercraft having a hull with a mounting opening, the jet propulsion unit including a power head and a jet pump housing secured to the power head, the mounting system including a power transmission portion disposed on the jet pump housing, and a mounting apparatus associated with the transmission portion for mounting the propulsion unit directly to the hull.

Abstract: A hull for a boat comprising a main hull bottom having a pair of hull bottom sides, each side having a first longitudinal inner edge and a second outer edge, with the hull bottom sides connected along the first inner edges and extending transversely upwardly and outwardly therefrom in a generally "V" shaped transverse cross section, each of the hull bottom sides having a main portion angled outwardly and upwardly from the first inner edge, and each of the hull bottom sides having a chine angled outwardly and downwardly from the main portion along a majority of the length of the second edge, a substantially vertical transom at the aft ends of the hull bottom sides, and a pair of raised after planing surfaces having forward ends at the transom and projecting aft of the transom and substantially parallel to and stepped slightly above the hull bottom sides immediately in front of the after planing surfaces, and the raised after planing surfaces also projecting aft generally parallel to and slightly above the chin

Abstract: Marine apparatus comprising a boat hull including opposed walls extending generally in the fore and aft direction, and a mounting bracket connected to the walls for supporting a propulsion unit for pivotal movement relative to the boat about a generally horizontal axis.

Abstract: Disclosed herein is an outboard motor comprising a propulsion unit including a lower unit having port and starboard sides and comprising a drive shaft housing having an upper end, a power head including an engine fixedly attached to said upper end of said drive shaft housing, and an engine cover assembly comprising a starboard lower cover member extending downwardly to said lower end of said drive shaft housing and including an inwardly open recess, a port lower cover member extending downwardly to said lower end of said drive shaft housing and including an inwardly open recess, and means connecting together said port and starboard cover members independently of said lower unit and in surrounding covering relation to said drive shaft housing, and means resiliently supporting said lower cover members on said lower unit and including rubber mounts respectively extending from said port and starboard sides of said lower unit and into said inwardly open recesses of said lower cover members.

Abstract: A vibration absorbing steering device for an outboard motor having a swivel bracket constructed and arranged for mounting to a transom bracket of a boat and defining a vertical passageway includes a tubular pivot shaft being pivotally engaged in the passageway, an engine mount bracket designed to mount the engine for rotation with the pivot shaft, and a vibration absorbing torque tube for absorbing vibration generated by the engine. The torque tube is vertically disposed within the tubular pivot shaft and is secured at one end to the pivot shaft. A tiller arm has a pivot end attached to the upper end of the torque tube so that the tiller arm is connected to the engine mount bracket through the torque tube, and the torque tube absorbs vibration from the engine which would normally be transmitted through the tiller arm to the operator. In addition to absorbing engine vibration, the present device also permits positive steering control of the motor by manipulation of the tiller arm.