Abstract: An outboard motor attached to a hull includes a body, a body driving device, and a control device. The body includes an engine and a propeller shaft. The propeller shaft is configured to be rotated by a drive force from the engine. The body is configured to pivot about a tilt axis extending in a lateral direction of the hull. The body driving device is configured to drive the body about the tilt axis. The control device is programmed to control the body driving device so that a rear end of the propeller shaft is positioned higher than a front end of the propeller shaft when the control device determines that the propeller shaft is to rotate in a direction in which the hull is propelled in reverse.

Abstract: An outboard motor attached to a hull includes a body, a body driving device, and a control device. The body includes an engine and a propeller shaft. The propeller shaft is configured to be rotated by a drive force from the engine. The body is configured to pivot about a tilt axis extending in a lateral direction of the hull. The body driving device is configured to drive the body about the tilt axis. The control device is programmed to control the body driving device so that a rear end of the propeller shaft is positioned higher than a front end of the propeller shaft when the control device determines that the propeller shaft is to rotate in a direction in which the hull is propelled in reverse.

Abstract: A control unit for a boat propulsion system individually controls the forward and reverse propulsion directions, the propulsion force, and the steering angle of each of a plurality of boat propulsion units so that a point of action of a first resultant force is positioned behind a point of action of a second resultant force when the control unit receives an operational command from an operation device for travel in a lateral direction of a hull. The first resultant force is a resultant force of propulsion forces generated by the first port-side propulsion unit and the first starboard-side propulsion unit. The second resultant force is a resultant force of propulsion forces generated by the second port-side propulsion unit and the second starboard-side propulsion unit.

Abstract: An electronic control device on an internal combustion engine side connected to an abnormal internal combustion engine detects an abnormality and outputs the abnormal signal; the target throttle opening angle signal is transmitted to the electric throttle actuator to set a throttle opening angle of an abnormal internal combustion engine to a predetermined opening angle; the abnormal signal is transmitted to the electronic control devices on a remote control device side of a normal internal combustion engine; and the electronic control devices on a remote control device side of a normal internal combustion engine, on receiving the abnormal signal, transmit the target throttle opening angle signal to the electronic control devices on an internal combustion engine side of a normal internal combustion engine.

Abstract: A display device for a watercraft indicates various status data values regarding the conditions of an outboard motor, such as cooling water temperature, battery voltage, and oil level. The display device has a dot matrix display as a part of display region, in which dots capable of being turned on and off are arranged in the form of a matrix, and the status data values are indicated via the lighting pattern of the dots.

Abstract: A steering system for a boat with three or more propulsion units allows the operator to operate the boat in the same manner before and after a failure of one of the propulsion units. The steering system includes not more than two control levers to control three or more propulsion units. A controller can automatically change the control arrangement between the two control levers and the propulsion units when any of the propulsion units is turned off.

Abstract: A remote control device for controlling a propulsion unit of a boat is provided. The remote control device comprises a main body having a shift lever. A housing board is coupled to the main body of the remote control device and extends in a downward direction. The housing board houses a remote control engine control unit that provides an operation output signal to the propulsion unit based on an operation input signal received from the shift lever. In one embodiment, an operator can access the remote control engine control unit from either a starboard side or a port side of the boat. The remote control device can include an additional housing board that is capable of being attached to and detached from the housing board that is coupled to the main body.

Abstract: A watercraft propelled by an outboard motor includes an inspection system. The inspection system includes a terminal computer that conducts an inspection of an engine control device and a control unit. The computer includes a program that performs an inspection process that provides the control device with a command signal to start an inspection of the control device and that requests the control device to output a first response signal. The process determines whether the response signal is consistent with a first specified signal. The process provides the control unit with a command signal to start an inspection of the control unit and requests the control unit to output a second response signal. The process determines whether the second response signal is consistent with a second specified signal. The control device controls a throttle actuator and a shift actuator based upon the second response signal and provides the inspection system with an operating signal.

Abstract: A steering system for a boat with three or more propulsion units allows the operator to operate the boat in the same manner before and after a failure of one of the propulsion units. The steering system includes not more than two control levers to control three or more propulsion units. A control means automatically changes the control arrangement between the two control levers and the propulsion units when any of the propulsion units is turned off.

Abstract: A diagnostic system is provided for a watercraft that is propelled by an outboard drive. Sensors can detect conditions of components related to at least the operation of the outboard drive. The diagnostic system can leave inside and outside computers. The inside computer is placed in the watercraft, while the outside computer is placed out of the watercraft. The outside computer is installed with a program to provide the inside computer with an instruction signal to start a diagnosis on the components. The inside computer is installed with a program to provide sensors with a commencement signal to start checking the components, to require the sensors to provide a detection signal, to collect detection signals, and to provide the outside computer with a result of the checking based upon the detection signals. The program of the outside computer additionally controls a monitor of the outside computer to indicate the conditions of the components based upon the result of the checking.

Abstract: A propulsion system for a watercraft includes an engine. An air intake device delivers air to a combustion chamber. A throttle valve regulates an amount of the air. A control device sets the throttle valve to a desired position. A remote controller provides the control device with the desired position. The engine can include an auxiliary intake device that delivers supplemental air to the combustion chamber. A control valve normally shuts the supplemental air from the combustion chamber. The control device determines whether an abnormal condition occurs in setting the throttle valve to the desired position. The control device determines whether the amount of the air is insufficient. The control device controls the control valve to allow the supplemental air to move to the combustion chamber when the control device determines that the abnormal condition occurs and the amount of the air is insufficient.

Abstract: A remote control device for controlling a propulsion unit of a boat is provided. The remote control device comprises a main body having a shift lever. A housing board is coupled to the main body of the remote control device and extends in a downward direction. The housing board houses a remote control engine control unit that provides an operation output signal to the propulsion unit based on an operation input signal received from the shift lever. In one embodiment, an operator can access the remote control engine control unit from either a starboard side or a port side of the boat. The remote control device can include an additional housing board that is capable of being attached to and detached from the housing board that is coupled to the main body.

Abstract: An electronic control device on an internal combustion engine side connected to an abnormal internal combustion engine detects an abnormality and outputs the abnormal signal; the target throttle opening angle signal is transmitted to the electric throttle actuator to set a throttle opening angle of an abnormal internal combustion engine to a predetermined opening angle; the abnormal signal is transmitted to the electronic control devices on a remote control device side of a normal internal combustion engine; and the electronic control devices on a remote control device side of a normal internal combustion engine, on receiving the abnormal signal, transmit the target throttle opening angle signal to the electronic control devices on an internal combustion engine side of a normal internal combustion engine.

Abstract: A propulsion system for a watercraft includes an engine. An air intake device delivers air to a combustion chamber. A throttle valve regulates an amount of the air. A control device sets the throttle valve to a desired position. A remote controller provides the control device with the desired position. The engine can include an auxiliary intake device that delivers supplemental air to the combustion chamber. A control valve normally shuts the supplemental air from the combustion chamber. The control device determines whether an abnormal condition occurs in setting the throttle valve to the desired position. The control device determines whether the amount of the air is insufficient. The control device controls the control valve to allow the supplemental air to move to the combustion chamber when the control device determines that the abnormal condition occurs and the amount of the air is insufficient.

Abstract: A propulsion system for a watercraft includes an engine. An air intake device delivers air to a combustion chamber. A throttle valve regulates an amount of the air. A control device sets the throttle valve to a desired position. A remote controller provides the control device with the desired position. The engine can include an auxiliary intake device that delivers supplemental air to the combustion chamber. A control valve normally shuts the supplemental air from the combustion chamber. The control device determines whether an abnormal condition occurs in setting the throttle valve to the desired position. The control device determines whether the amount of the air is insufficient. The control device controls the control valve to allow the supplemental air to move to the combustion chamber when the control device determines that the abnormal condition occurs and the amount of the air is insufficient.

Abstract: A propulsive force controlling apparatus controls a propulsion system attached to a hull of a marine vessel. The propulsion system includes a motor, a propulsive force generating member which receives a torque from the motor to generate a propulsive force, a clutch mechanism which operates only in either a coupling state which permits transmission of the torque from the motor to the propulsive force generating member with virtually no slippage and a decoupling state which prohibits the transmission of the torque from the motor to the propulsive force generating member, and a clutch actuator which actuates the clutch mechanism.

Abstract: A control system for an internal combustion engine includes a fuel injection control system having a first mode, wherein fuel injectors are controlled based on engine condition data supplied by a first group of sensors, and a second mode wherein fuel injectors are controlled based on engine condition data supplied by a second group of sensors. During normal operation of the engine, the control system switches between the first and second control modes based upon an engine operating condition (e.g., engine speed and/or engine load). If one of the sensors of the first group of sensors malfunctions, the control system controls the engine only in accordance with the second control mode. If one of the sensors of the second group of sensors malfunctions, the control system controls the engine only in accordance with the first control mode.

Abstract: A watercraft has an engine that is controlled to reduce the likelihood of engine damage and rider discomfort when the watercraft engine speed is rapidly increased due to a lack of load on the propulsion unit. The engine is controlled by a method that detects engine speed and reduces the power output of the engine by varying degrees or restores the power output of the engine by varying degrees depending on the speed of the engine relative to plural predetermine speeds.

Abstract: A display device for a watercraft indicates various status data values regarding the conditions of an outboard motor, such as cooling water temperature, battery voltage, and oil level. The display device has a dot matrix display as a part of display region, in which dots capable of being turned on and off are arranged in the form of a matrix, and the status data values are indicated via the lighting pattern of the dots.

Abstract: A watercraft battery control system monitors a battery charge. The system informs the watercraft operator when the battery charge is below a predetermined value. Alternatively, the system automatically controls engine operation by starting the engine or by increasing the speed of the engine to allow a generator to replenish the battery charge when the battery charge has fallen below a predetermined value. By informing the user of an inadequate battery charge, the user can start the engine an recharge the battery. Alternatively, the system automatically maintains the battery at a predetermined charge level to ensure safe and enjoyable watercraft operation.