Abstract: A tilt-trim subsystem assembly affixed to an outdrive of a stern drive that may be supported by a gimbal unit and may be configured to rotate about a predetermined axis to impart a desired trim or tilt to the drive system is provided. The tilt-trim assembly has one respective end thereof configured to pivotally receive one anchor pin supported by the outdrive. The assembly includes one or more cylinders having one end thereof pivotally connected to another anchor pin so that when the cylinder is actuated the outdrive and the tilt-trim subsystem assembly are jointly rotated about the predetermined axis.

Abstract: A fuel delivery system uses a single electric fuel pump to deliver fuel to a fuel injected engine and returns excess fuel to the single electric fuel pump via a vapor separator and two pressure regulators. A primer bulb draws fuel from a fuel tank with a fuel supply line and transfers the fuel to the single electric fuel pump. The single electric fuel pump delivers fuel to a fuel rail assembly, which enables fuel to be distributed to each fuel injector during engine operation. A fuel return line connects the fuel rail assembly to the single electric fuel pump via the vapor separator to remove excess fuel from the fuel rail assembly and to transfer the excess fuel back to the single electric fuel pump for re-circulation. The first pressure regulator maintains a substantially constant pressure within the fuel injectors while the vapor separator purges entrained gas from the excess liquid fuel to avoid vapor lock.

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: Engine control apparatus and methods for avoiding heavy soot production yet providing smooth engine acceleration and deceleration without significant engine RPM increases and decreases with small throttle movements are described. In one embodiment, once the fuel injection angle reaches the angle at which soot formation begins, one or more cylinders are controlled to operate with later injection angles and lower fueling, which results in lower torque production and lower soot formation, while at the same time the remaining cylinders are set to operate with advanced injection angles and higher fueling, which results in a homogenous mixture of air and fuel, higher torque, and also lower soot formation. Therefore, for a first range of throttle positions, all cylinders operate in the stratified combustion mode.

Abstract: A water jet propulsion unit having an articulating exit nozzle assembly which serves as both a thrust nozzle and a steering nozzle. The assembly includes a flow-through inner housing or duct having a flanged portion with an inlet and a ball-shaped portion with an outlet, and a convergent nozzle having a spherical socket which fits around the ball-shaped portion of the inner duct. This ball and socket arrangement allows the nozzle to rotate relative to the ball-shaped portion of the inner duct. A limit pin on the duct projects into a slot formed in the nozzle wall to prevent rotation of the nozzle about a centerline of the duct. Abutment of the pin with the ends of the slot limit the trim angle of the nozzle to a predetermined range. A bracket is attached to the nozzle for controlling the angular position of the nozzle relative to the inner duct.

Abstract: A propeller flare having a periodic shape and extending from the aft end of the propeller hub is described. The periodic shape of flare provides that the trailing edge, or aft end, of the propeller hub is increased only at locations where such increased material is needed to prevent exhaust gases from reaching the lower pressure region on the suction side of the blades. By only increasing the hub aft end at such selected locations, the efficiency and speed loss due to increased drag is minimized. In one embodiment, the flare is configured for a three blade propeller and includes three flare sections. Each flare section has a helical cross-sectional shape, and ramps are located intermediate adjacent flare sections. Each ramp is aligned with one of the propeller blades, and each ramp has a pitch at least about equal to the pitch of blades. Reliefs are located adjacent each ramp, and each relief extends from an aft end of the ring toward a fore end of the ring.

Abstract: An outboard motor includes a propulsion unit having a power head which includes an internal combustion engine, a lower unit including a drive shaft housing fixed to the engine and a propeller shaft joined by the lower unit driven by the engine and having thereon a propeller. A cowling extends over the engine downwardly to the drive shaft housing defining an enclosed space containing the engine. An opening is provided to the enclosed space proximate the juncture between the cowling and the drive shaft housing. A plurality of electrical cables enter the enclosed space through the opening. A sealed housing is mounted to a side of the engine and contains a plurality of electrical devises for operating the engine. The cables connect to preselected devices by means of water-tight connections on the housing.

Abstract: A fuel delivery system for a boat having an internal combustion engine is provided. The system provides a source of fuel. A fuel supply conduit is connected to the source of fuel to deliver fuel to the engine. A fuel impermeable housing has one end coupled to the source of fuel and defines a passageway that receives the fuel supply conduit interiorly of the boat. The passageway is hermetically sealed relative to the interior of the boat and provides a return path into the fuel source to any fuel that may spill in the passageway.

Abstract: Computerized system and method for controlling a plurality of internal combustion engines are provided. The system includes a respective speed sensor coupled to a corresponding engine to supply a respective speed sensor signal indicative of each engine's speed. The system further includes an electronic control unit coupled to receive each respective speed sensor signal. The control unit in turn includes a comparator module configured to compare each speed sensor signal relative to one another and supply a comparator output signal based on the magnitude of any differences between the engine speed signals. A processor module is responsive to the comparator output signal to adjust one or more engine operational parameters of one or more of the plurality of engines.

Abstract: A tilt-trim subsystem and method for a boat propulsion system is provided. A stern bracket is mounted on a transom of the boat. A swivel bracket is pivotally supported relative to the stern bracket for rotation about a generally horizontal axis. The subsystem includes a tilt and trim assembly having at least one cam pivotally supported by the stern bracket. The cam is configured to impart a relatively slow rate of rotation to the swivel bracket, at least when there is driving contact between the cam and the swivel bracket within a predetermined angular range for trimming, as compared to a rate of rotation within a predetermined angular range for tilting.

Abstract: A propeller including, in one embodiment, a flare having a sinusoidal, or tulip, shape is described. The flare is located at a trailing edge of the propeller, and the sinusoidal flare shape of the propeller trailing edge has reduced stresses as compared to stresses associated with known flare rings. Specifically, stress is reduced in the sinusoidal flare shape due to smooth trailing surfaces and the uneven edge of the flare. As a result, and during fabrication, potential for cracking the trailing edge of the flair is reduced. In addition, the flare has greater strength as compared to at least some known flare rings in that stresses are more evenly distributed along the tulip shaped trailing edge.

Abstract: Disclosed herein is a fuel supply system comprising a carburetor including a fuel bowl, an air induction passage including therein a venturi, a throttle valve located in the air induction passage downstream of the venturi, a fuel enrichment conduit communicating between the fuel bowl and the air induction passage downstream of the throttle valve, and a temperature responsive valve for admitting air to the fuel enrichment conduit when the ambient temperature is above a predetermined level and for admitting air to the air induction passage when the engine temperature is below the predetermined level.

Abstract: A propeller assembly that includes, in an exemplary embodiment, a cantilever spring for securing a propeller to a propeller shaft is described. In the exemplary embodiment, the propeller assembly includes a thrust bearing which tightly fits to an inclined surface of the propeller shaft. The thrust bearing includes an annular slot which forms a tight fit with one end of a hub of the propeller and one end of the spring. The propeller hub has a cylindrical shape, and a plurality of blades extend from an outer surface of the hub. A bore extends through the propeller hub, and the spring extends into the hub bore. The assembly further includes a washer and a nut which engages to a threaded end of the propeller shaft.

Abstract: A seal system for a motor cover of an outboard motor includes a resilient hollow tubular seal member for providing a substantially water impervious seal at a joint between the motor cover and an adjoining housing member of the motor and wherein the seal member is pressurized with air to expand in the joint.

Abstract: An ETV-type pump jet having a stator housing with an attachment for minimizing the mismatches between the velocity and direction of the exhaust gas stream flowing out of a stator vane outlet and the velocity and direction of boat and pump jet motion. In one embodiment, a multiplicity of exhaust ducts are attached to the external surface of the stator housing, each exhaust duct being positioned to be in flow communication with the exhaust gas outlet of a respective hollow stator vane. Exhaust gases exiting the exhaust outlets are redirected by the inner surfaces of the ducts to flow in parallel with the rotor shaft axis. In another embodiment, a circumferential exhaust skirt made of sheet metal is substituted for the exhaust ducts. The exhaust skirt surrounds the stator housing and redirects the exhaust gas stream to be substantially parallel with the surrounding water flow.

Abstract: An internal combustion engine assembly including an internal combustion engine including an engine block having at lest one cylinder, a piston mounted within the cylinder for reciprocal movement in the cylinder, a fuel injector for injecting fuel into the cylinder, the fuel injector initiating a fuel injection event at a predetermined time and a circuit for generating a spark in the cylinder a predetermined amount of time after the injection event to cause combustion of fuel in the cylinder.

Abstract: A method and apparatus for optimizing desired operational characteristics of an engine having a positionable throttle and a plurality of cylinders wherein data representing the same gross amount of fuel to be injected into all of the cylinders at any given throttle position and engine RPM setting is provided to obtain a gross optimization of the desired engine operational characteristics and the data representing the gross amount of fuel to be provided to each cylinder is adjusted for each cylinder individually at any given RPM setting to provide data representing a specific amount of fuel to be provided to each cylinder individually to optimize the desired engine operational characteristics with respect to fuel injection.

Abstract: An internal combustion engine having fuel injection with a protrusion placed between a fuel injection nozzle and a spark plug in the combustion chamber. The protrusion shields the core nose of the spark plug, but not the gap between the center electrode and ground electrode of the spark plug. In this fashion, combustion is enhanced and carbon buildup on the porcelain body of the spark plug is prevented, thereby lessening the likelihood of a malfunction by the spark plug.

Abstract: A pump jet apparatus having a double-walled stator housing containing an annular passage through which exhaust gas can flow. Gas enters the annulus through an exhaust gas inlet or port formed in the outer stator shell at the top of the stator housing, flows in two streams around the annular passage formed between the inner and outer stator shells, and exits the stator housing through exhaust outlets or ports formed in the outer stator shell near the bottom of the stator housing. The streams of exhaust gas and impelled water flowing through the stator housing of the pump jet are kept separate by the inner stator shell.

Abstract: An ignition system for an internal combustion engine that generates more ignition sparks per ignition event, i.e., per cylinder, per cycle, when the engine is operated in the stratified fuel injected mode than when the engine is operated in the homogeneous fuel injection mode.