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: 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 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 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 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: 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: An outboard motor has a quieter operating recoil starter arrangement. The recoil starter has a starter drum with a dog clutch arrangement having two dog cam members. The dog cam members rotate between an initial position and an extended position under the influence of a clutch drive member. Specifically, the dog cams each have a portion which engages a starter pulley when a starter rope is pulled. The dog cams are configured to extend minimally into a corresponding slot of the starter pulley when in their extended position. Such configuration results in less chatter when the starter pulley speed exceeds the starter drum speed upon ignition of the engine.

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 grommet assembly for an outboard motor includes a grommet having a step, a flexible sleeve having a step and a connector configured to engage the step on the grommet and the step on the flexible sleeve. Preferably, the connector is in the form of an annular connector formed of two semicircular members connected to one another. Additionally, the step formed on the sleeve preferably is defined by a helical groove formed on the flexible sleeve. The connector preferably includes a helical wall defining a step that corresponds to the helical step formed on the flexible sleeve. The grommet assembly may also be in the form of a kit including a grommet having a step and a connector configured to engage the step on the grommet and a step formed on an existing flexible sleeve.

Abstract: An improved cowling arrangement for an outboard motor powered by an internal combustion engine. The improved arrangement includes a flywheel cover and cowling that incorporate upwardly and downwardly extending ribs which are positioned along an air path between the air vent of the outboard motor and the throttle body of the motor. These ribs act as labyrinth-type seals which prevent water entering the air vent from contacting the throttle body. Also disclosed is an improved cowling arrangement that prevents water pooled on the flywheel cover from draining onto the throttle body when the motor is tilted, such as when the watercraft banks into a turn.

Abstract: A fuel injection system for an engine includes an improved construction to inhibit heating of the fuel. A fuel reservoir is arranged to store the fuel therein. A fuel pump is provided for delivering the fuel in the reservoir to a fuel injector which sprays fuel toward a combustion chamber of the engine. The fuel pump is driven by an electric motor that is intermittently powered. In one embodiment, a control device is provided for controlling the duration for which the electric motor is powered. A duty ratio of the duration is preferably determined in response to an amount of the fuel that is required to be sprayed by the fuel injector.

Abstract: A feed back control system and method for direct injected engines useful in a start up operation that utilizes a fuel pressure condition sensor. At the commencement of cranking, the feed back control system adjusts at least the initiation of fuel injection based upon the output from the fuel pressure condition sensor. This removes a great shift in the fuel pressure between before and after starting of the engine and eventually promotes operator's feeling and also improves exhaust emissions.

Abstract: Several embodiments of combustion chamber configurations for direct injected engines having a substantial recess in the cylinder head in which the fuel injector is positioned and injects. The injector is arranged so as to be disposed over the exhaust port and to spray toward the auxiliary scavenge port. However, the spray pattern is such that fuel will not impinge upon the cylinder head surface and so that the scavenge flow will direct the fuel away from the cylinder walls and toward the head of the piston for cooling and better vaporization. This also ensures that fuel will not pass out of the exhaust port.

Abstract: A control device and method of injected fuel for a direct cylinder injected, internal combustion engine. The control device primarily increases the fuel amount to a certain amount under the conditions that the engine load is increasing such as an acceleration condition. The device, however, when a quick change of the load increase occurs, reduces the increase amount of the fuel at the first combustion cycle or cycles. Although there may be other controls, the device then gradually increases the fuel amount to the amount until the primary amount at intervals of at least one combustion cycle. The quick change of the load increase is, in one aspect of the invention, defined as that a crankshaft rotational speed is within a predetermined range and the throttle valve opening is larger than a predetermined value.

Abstract: A cooling system for an outboard motor having a water propulsion device and an internal combustion engine positioned in a cowling, the engine having an output shaft arranged to drive the water propulsion device, is disclosed. The cooling system includes a coolant delivery mechanism driven by the engine, the delivery mechanism arranged to deliver coolant selectively to at least one of two coolant jackets of the engine. One coolant jacket is associated with at least one combustion chamber of the engine. The other cooling jacket is associated with an exhaust manifold for that combustion chamber. The cooling system also includes at least one coolant drain line through which coolant may drain from each of the cooling jackets of the engine.

Abstract: An outboard motor comprises an internal combustion engine and a protective cowling that surrounds the engine. The cowling comprises at least an upper portion and a lower portion. The engine comprises a cylinder block that defines a cylinder bore. A cylinder head member is fixed at one end of the cylinder block and encloses one end of the cylinder bore. A crankcase member is fixed at the other end of the cylinder block and encloses the other end of the cylinder bore. The crankcase member forms a crankcase chamber. A piston is positioned within the cylinder bore. A crankshaft is rotably journaled in the crankcase chamber and is connected to the piston. The piston, the cylinder bore and the cylinder head together define a combustion chamber. The cylinder block, the cylinder head member and the crankcase member together defining an engine body. A first air intake conduit communicates with the engine and extends generally along a side of the engine body.

Abstract: A marine propulsion housing arrangement includes an improved construction for inhibiting an influx of water into the housing and for protecting the components thereof. A marine outboard drive comprises a drive unit and at least a swivel bracket that supports the drive unit for pivotal movement with a steering shaft. At least one mount assembly is provided for unifying the drive unit and the steering shaft. The mount assembly includes at least one mount members affixed to the drive unit and a hub member united with the mount member. The hub member is connected to both the drive unit and the steering shaft so as to unify them. A mount cover generally covers both of the mount member and the hub member.

Abstract: An internal combustion engine includes an improved feedback control system and method for operating the engine to provide the desired air/fuel ratio under all running conditions without causing unsettling variations in engine speed and torque as adjustments to the air/fuel ratio are made. The feedback control operates to modify the fuel/air ratio from that achieved by a basic setting that is derived from parameters of engine performance so as to maintain the desired ratio. The control system also adjust the ignition timing while the air and fuel ratio is adjusted toward the desired ratio to maintain generally constant engine speed and torque.

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.