Abstract: An outboard motor includes an improved arrangement for an exhaust system, in association with a lubricant tank and a cooling system, for a four-cycle internal combustion engine that powers the outboard motor. The cooling system discharges coolant independent of an exhaust pipe and an expansion chamber of the exhaust system so as to inhibit an influx of coolant into the engine should the engine become temporarily disabled. In addition, the cooling system provides a pool or bath of coolant between the exhaust pipe and the lubricant tank to inhibit excessive heating of these components during normal and abnormal running conditions (i.e., if the engine becomes disabled).

Abstract: A personal watercraft features a four-cycle engine. The four-cycle engine has an intake valve and an exhaust valve. The intake valve and the exhaust valve are controlled through a use of a cam drive arrangement. The cam drive arrangement is contained within a protective housing. A number of waterjackets are provided to the housing to control the temperature within the housing. In addition, the watercraft features a protective housing in which a starter motor is mounted to the cylinder block. The housing features two members that can be mounted to the cylinder block together while one member can be removed for access to the starter motor.

Abstract: An engine includes an air induction system, a fuel supply system, a lubrication system and a ventilation system. The fuel supply system has a fuel reservoir in which a space for fuel vapors is defined. The lubrication system lubricates a component of the engine with lubricant. The ventilation system couples a crankcase of the engine with the air induction system so as to deliver oil vapors in the crankcase to the air induction system. A fuel vapor passage is arranged to couple the space of the fuel reservoir with the ventilation system.

Abstract: An outboard motor features a compact throttle control and transmission shifting control on a handle connected to a tiller. An interlock is designed to limit the maximum engine speed at which the engine can be operated when in the transmission is in neutral and to lock the transmission in neutral or out of neutral when the engine is operated at a speed greater than a second speed that is less than the maximum speed.

Abstract: A lubrication system for an outboard motor engine includes a pump housing includes an inlet port through which lubricant enters the pump housing and an outlet port through which the lubricant is discharged from the pump housing. Both the crankshaft and the driveshaft extend through an opening defined at the pump housing and are couple with each other within the pump housing. A first seal member is disposed around the crankshaft for sealing a first location between an outer surface of the crankshaft and a first inner surface of the pump housing that defines at least a portion of the opening. A second seal member is disposed around the driveshaft for sealing a second location between an outer surface of the driveshaft and a second inner surface of the pump housing that also defines at least a portion of the opening.

Abstract: A tilt stop mechanism for an outboard drive assembly includes an improved construction that is easy to handle and can be provided in a relatively narrow space of a support assembly. The support bracket includes a pair of transversely spaced portions. At least a portion of the outboard drive assembly is interposed between the spaced portions. A tilt pin couples the drive assembly to the support bracket for pivotal movement about a tilt axis extending generally horizontally. A tilt stop member is coupled to the drive assembly for pivotal movement about a pivot axis extending generally horizontally. The tilt stop member has at least one stopper portion extending between the drive assembly and the support bracket when the drive assembly is in a tilted-down position. The support bracket has at least one recess. The stopper portion engages with the recess by the pivotal movement of the tilt stop member when the outboard drive is in a tilted-up position.

Abstract: An arrangement of components for an engine includes an improved construction. An exhaust system of the engine has an exhaust manifold extending along an cylinder body. At least a part of an air induction system of the engine exists to overlap with the exhaust manifold in a view along an extending axis of the exhaust manifold. A cooling system having at least two coolant passages is further provided. A coolant flow control mechanism is arranged to prevent only the coolant within one of the passages from flowing therethrough when temperature of the coolant is lower than a predetermined temperature.

Abstract: An outboard motor comprising a water propulsion device and a cowling housing an internal combustion engine is disclosed. The engine has a body defining at least one combustion chamber and an output shaft arranged to drive the water propulsion device. The cowling has a front end and a rear end. The motor includes a handle which generally encircles at least a portion of the cowling, the handle having at least one gripping portion at the front or rear end of the cowling.

Abstract: An outboard motor includes a cowling covering an internal combustion engine having a plurality of horizontally arranged cylinders. A high pressure fuel pump drive unit is arranged so as to be offset from the axes of the cylinders, at an upper end of the engine. The electrical system is provided on a first side of the engine body and a fuel system is provided on the opposite side of the engine body. Arranged as such, the components of the engine form a compact unit thus reducing the overall size of the cowling. Additionally, fuel lines and electrical conduits which connect the various components of the respective fuel and electrical systems are separated from each other.

Abstract: A jet propelled watercraft having an improved extension assembly for dampening pulsations from the impeller of the jet propulsion unit and also for mounting the jet propulsion unit. The structure simplifies the overall assembly and permits individual tuning with conventional units.

Abstract: An engine decompression device includes an improved construction to release at an exceedingly slow engine speed. The engine has a camshaft that actuates at least one exhaust valve and extends generally vertically. The decompression device has an actuator mounted on the camshaft for pivotal movement about a pivot axis extending generally normal to an axis of the camshaft. The actuator includes a cam section that holds the exhaust valve in an open position and a sinker section that moves with centrifugal force produced by relatively slow rotation of the camshaft so as to release the cam section from holding the exhaust valve open.

Abstract: The invention provides an improved oil injection lubrication system for two-cycle engines. The system includes a variable output oil pump, the output of which can be varied in relation to the throttle level. The system also includes a solenoid valve unit containing a plurality of solenoid valves that further regulates the flow of oil from the oil pump to each cylinder. An electronic control unit sends control signals to the soleniod valve unit to regulate the flow of oil based upon engine operating conditions in accordance with a controle scheme. The combination of the variable output oil pump and the solenoid valve unit enables the solenoid valves to be activated with a lighter duty cycle, which reduces the amount of power consumed by the solenoid valve unit.

Abstract: An outboard motor comprises an engine mounted within an engine compartment. The engine comprises an induction system having an induction passage extending between an air intake box to a combustion chamber. A throttle valve is positioned along the passage. A bypass passage communicates with the passage at a location between the throttle valve and the combustion chamber. An adjustable valve controls flow through the bypass passage. The adjustable valve can be closed at a first rate if a transmission of the outboard motor is engaged and at a second rate if the transmission is disengaged.

Abstract: The present vehicle data system collects, encodes, transmits, decodes, and displays engine and vehicle operation information. In one mode, an engine control unit of an outboard boat motor receives a plurality of engine and vehicle operation parameters from a plurality of sensors. The engine control unit encodes the plurality of parameters in a single signal and transmits the encoded signal to a display unit over a signal line. The display unit decodes the encoded signal to extract the plurality of parameters and displays the extracted parameters to the vehicle operator.

Abstract: An oil pump for a lubricating system of an outboard motor is disclosed. The motor has a cowling defining an engine compartment, a water propulsion device, and a guide member having an upper surface and a lower surface, the guide member positioned in the cowling and generally dividing the engine compartment into an upper part and a lower part. An engine is positioned in the upper part of the engine compartment within the cowling and has an output shaft arranged to drive the water propulsion device. The lubricating system includes an oil pan positioned below the guide member and an oil passage leading from the pan through the guide member. The oil pump is positioned in the upper part of the engine compartment, but below the engine, and is driven by a lower end of the output shaft of the engine which extends below the engine, the oil pump having an oil inlet in communication with the oil passage through the guide member.

Abstract: A control system for a multicylinder direct injection engine determines a control variable for each cylinder based on engine speed and engine load. The control variable can be altered depending upon an operating temperature of each cylinder independently of the others. The operating temperature of each cylinder is monitored through a temperature sensor disposed on the fuel injector nozzle. The cylinders having nozzles operating at a temperature lower than a normal temperature or normal range of temperatures can have the control variable altered to increase the power of that cylinder and the temperature of that cylinder. The cylinders having nozzles operating at a temperature higher than a normal temperature or normal range of temperatures can have the control variable altered to lower the operating temperature of the nozzle.

Abstract: A fuel supply system is disclosed for a direct injected “V” type engine powering an outboard motor. The fuel supply system includes a pump for supplying fuel from a tank to a vapor separator. An electrical pump delivers fuel from the vapor separator to a mechanical high pressure pump, which delivers fuel under high pressure to a fuel manifold and further to a pair of fuel rails. The fuel rails supply fuel to fuel injectors for delivering fuel to the combustion chambers of the engine. Recesses are formed on a side of each cylinder head and one fuel rail is positioned within each recess. The mechanical high pressure pump is positioned vertically above the uppermost fuel injector so that any fuel vapor within the fuel rails will rise toward the fuel pump. Fuel vapor that accumulates within the high pressure fuel pump is returned to the vapor separator.

Abstract: A four-cycle outboard motor has a lubricating system designed with external gas transfer pipes. Additionally, an internal gas transfer passageway is arranged to encourage the gases contained within the lubrication pan to be expelled through the secondary passageways without substantially blocking a lubrication return line from a camshaft chamber or a crankshaft chamber. The outboard motor features an inline vertically oriented cylinder bank, such that oil introduced at an upper region and drains back to a lubrication pan through the lubrication return passageways arranged at a lower portion of the camshaft chamber and the crankshaft chamber.

Abstract: An outboard motor includes the direct fuel injection system. The outboard motor also includes an ECU that monitors various engine operating conditions and controls various engine operating parameters that are at least partially dependent on the positioning of the transmission. In instances in which the transmission is positioned in a neutral location, the load is decreased and therefore the ECU outputs one set of parameters. In similar low-speed operations, when the transmission is placed in a drive arrangement, the ECU outputs a second set of parameters due to the increased load. Several control routines are disclosed which facilitate low-speed operation, over-rev limiting, and engine warm-up.

Abstract: A two-cycle internal combustion engine for a watercraft that includes a cylinder block having a cylinder bore, a piston reciprocating in the cylinder bore and an exhaust port formed in the cylinder block. An exhaust path extends from the cylinder bore for exhausting combustion products from the cylinder bore. An exhaust control valve cooperates with the exhaust port and is movable between at least a first position for advancing the closing of the exhaust port so as to increase the compression ratio in the engine and a second position for delaying the closing of the exhaust port so as to decrease the compression ratio in the engine. Means for controlling the exhaust control valve between the first and second position are provided and are controlled in response to a watercraft condition.