Abstract: A system for determining an oil amount in a marine drive includes an oil level sensor that senses an oil level in the sump and temperature sensor sensing an engine temperature. A control module for the system is configured to determine that the engine temperature is greater than a temperature threshold, and that an engine speed exceeds a speed threshold for at least a predetermined time period or that a throttle position exceeds a throttle position threshold. If both such conditions are met, and a threshold drop in engine speed to an idle threshold is detected or a threshold change in throttle position to an idle position is detected, then an oil level in the sump is sampled with an oil level sensor. An oil amount is then determined based on the sampled oil level in the sump.

Abstract: A marine engine operates according to first and second sets of mapped parameter values to achieve a first fuel-air equivalence ratio and maintains a stable output torque while transitioning to operating according to third and fourth sets of mapped parameter values to achieve a different fuel-air equivalence ratio. The first and third sets of mapped parameter values correspond to a first combustion parameter. The second and fourth sets correspond to a second combustion parameter. The transition includes: (a) transitioning from operation according to a current value of the first combustion parameter to operation according to a target value thereof; (b) transitioning from operation according to a current value of the second combustion parameter to operation according to a target value thereof; and (c) timing commencement or completion of step (b) and setting a rate of step (b) to counteract torque discontinuity that would otherwise result when performing step (a) alone.

Abstract: A system for controlling propulsion of a marine vessel by a marine drive is provided, the marine drive having a marine engine that effectuates rotation of propulsor through a shift system that shifts amongst at least a forward gear position, a reverse gear position, and a neutral position. The system includes a remote control having a lever movable to provide a throttle demand input for controlling the marine engine and a shift demand input for controlling the shift system. A shift demand sensor measures a shift demand lever position to provide the shift demand input, and a throttle demand sensor measures a throttle demand lever positions to provide the throttle demand input. A control module is configured to detect shift demand sensor failure based on the shift demand lever position values and assign a predetermined throttle demand lever position as shift command position.

Abstract: Controlling a marine engine includes operating the engine according to an initial set of mapped parameter values to achieve a first target fuel-air equivalence ratio, determining a first actual fuel-air equivalence ratio, and using a feedback controller to minimize a difference between the first target and actual ratios. Feedback controller outputs are used to populate an initial set of adapt values to adjust combustion parameter values from the initial set of mapped parameter values. The method includes transitioning to operating the engine according to a subsequent set of mapped parameter values to achieve a different target fuel-air equivalence ratio. The method includes determining a second actual fuel-air equivalence ratio, using the feedback controller to minimize a difference between the second target and actual ratios, and using feedback controller outputs to populate a subsequent set of adapt values to adjust combustion parameter values from the subsequent set of mapped parameter values.

Abstract: A method of controlling an internal combustion engine of a marine propulsion device includes receiving a knock sensor signal over an analysis period in a combustion cycle of an internal combustion engine, and subdividing the analysis period into at least a first knock window and a second knock window. The method further includes determining that the knock sensor signal exceeds a threshold in each of the first knock window and the second knock window, and that the knock sensor signal intensity is greater in the first knock window than in the second knock window. At least one combustion parameter is then adjusted for the internal combustion engine to eliminate knocking.

Abstract: In one embodiment, a method of determining correct engine phase in an internal combustion engine without a cam sensor, the engine having a plurality of piston-cylinders that cause rotation of a crankshaft and a fuel delivery assembly associated with each of the plurality of piston-cylinders, the method comprising monitoring an engine parameter, modifying an amount of fuel delivered to a known piston-cylinder, advancing a spark time one of the plurality of piston-cylinders, and determining an actual engine phase based on a change in the engine parameter.

Abstract: A method for setting an engine speed of an internal combustion engine in a marine propulsion system to an operator-selected engine speed includes predicting a position of a throttle valve of the engine that is needed to provide the operator-selected engine speed, and determining a feed forward signal that will move the throttle valve to the predicted position. After moving the throttle valve to the predicted position, the method next includes controlling the engine speed with a feedback controller so as to obtain the operator-selected engine speed. The feed forward signal is determined based on at least one of the following criteria: an operator-selected control mode of the marine propulsion system; and an external operating condition of the marine propulsion system. A system for setting the engine speed to the operator-selected engine speed is also described.

Abstract: Systems and methods are for controlling internal combustion engines having a plurality of piston-cylinders that cause rotation of a crankshaft. A crankshaft sensor is configured to sense rotational speed of the crankshaft. A controller is configured to calculate an an engine speed increase for each piston-cylinder based upon the rotational speed of the crankshaft and then balance the engine speed increases of the respective piston-cylinders by modifying a combustion input to one or more of the piston-cylinders in order to reduce engine vibration.

Abstract: A method for determining a heading value of a marine vessel includes determining a first estimate of a direction of the marine vessel based on information from a first source and determining a second estimate of a direction of the marine vessel based on information from a second source. The method includes inputting the first estimate and the second estimate to a control circuit, which scales each of the first estimate and the second estimate and adds the scaled estimates together so as to determine the heading value. A system for determining a heading value of a marine vessel is also disclosed.

Abstract: A control system and method for deterring theft of a marine vessel. A security control circuit receives a transponder identification code from a transponder. The engine control circuit has a status that is based on a comparison of a stored identification code with the transponder identification code. The status of the engine control circuit is locked if the stored identification code does not match the transponder identification code and the status of the engine control circuit is unlocked if the stored identification code does match the transponder identification code. The security control circuit determines an arbitrated lock status of the control system based on a conjunctive analysis of the locked and unlocked statuses of a plurality of engine control circuits connected to a network bus, and indicates the arbitrated lock status to an operator of the marine vessel.

Abstract: Systems and methods are for drive-by-wire control of a marine engine. An input device is manually operated to provide operator inputs to an engine control unit (ECU) located with the engine. The ECU has a main processor that controls speed of the engine based upon the inputs. The ECU also has a watchdog processor that receives the inputs and that monitors operations of the main processor based upon the inputs. The operations of the main processor are communicated to the watchdog processor via a communication link. When communication between the main processor and watchdog processor fails, the watchdog processor determines whether the main processor is properly functioning based upon the speed of the engine.

Abstract: A system that controls the speed of a marine vessel includes first and second propulsion devices that produce first and second thrusts to propel the marine vessel. A control circuit controls orientation of the first and second propulsion devices about respective steering axes to control directions of the first and second thrusts. A first user input device is moveable between a neutral position and a non-neutral detent position. When a second user input device is actuated while the first user input device is in the detent position, the control circuit does one or more of the following so as to control the speed of the marine vessel: varies a speed of a first engine of the first propulsion device and a speed of a second engine of the second propulsion device; and varies one or more alternative operating conditions of the first and second propulsion devices.

Abstract: A fuel management system for a marine propulsion device provides a series of intermediate venting commands to a canister purge valve which controls the pressure decay within a fuel supply module in such a way that both the lift pump and high pressure pump within the module are provided with appropriate pressures to allow them to operate satisfactorily.

Abstract: A system and method is provided for efficiently changing controlled engine speed of a marine internal combustion engine in a marine propulsion system for propelling a marine vessel. The system responds to the operator changing the operator-selected engine speed, from a first-selected engine speed to a second-selected engine speed, by predicting throttle position needed to provide the second-selected engine speed, and providing a feed forward signal moving the throttle to the predicted throttle position, without waiting for a slower responding PID controller and/or overshoot thereof, and concomitant instability or oscillation, and then uses the engine speed control system including any PID controller to maintain engine speed at the second-selected engine speed.

Abstract: Drive-by-wire control systems and methods for a marine engine utilize an input device that is manually positionable to provide operator inputs to an engine control unit (ECU) located with the marine engine. The ECU has a main processor that receives the inputs and controls speed of the marine engine based upon the inputs and a watchdog processor that receives the inputs and monitors operations of the main processor based upon the inputs. The operations of the main processor are communicated to the watchdog processor via a communication link. The main processor causes the watchdog processor to sample the inputs from the input device at the same time as the main processor via a sampling link that is separate and distinct from the communication link. The main processor periodically compares samples of the inputs that are simultaneously taken by the main processor and watchdog processor and limits the speed of the engine when the samples differ from each other by more than a predetermined amount.

Abstract: A system that controls speed of a marine vessel includes first and second propulsion devices that produce first and second thrusts to propel the marine vessel. A control circuit controls orientation of the propulsion devices between an aligned position in which the thrusts are parallel and an unaligned position in which the thrusts are non-parallel. A first user input device is moveable between a neutral position and a non-neutral detent position. When the first user input device is in the detent position and the propulsion devices are in the aligned position, the thrusts propel the marine vessel in a desired direction at a first speed. When a second user input device is actuated while the first user input device is in the detent position, the propulsion devices move into the unaligned position and propel the marine vessel in the desired direction at a second, decreased speed without altering the thrusts.

Abstract: Systems and methods are for orienting a marine vessel having a marine propulsion device. A control circuit controls operation of the marine propulsion device. A user input device inputs to the control circuit a user-desired global position and a user-desired heading of the marine vessel. The control circuit calculates a position difference between the user-desired global position and an actual global position of the marine vessel and controls the marine propulsion device to minimize the position difference. The control circuit controls the marine propulsion device to orient an actual heading of the marine vessel towards the user-desired global position when the position difference is greater than a threshold. When the position difference is less than the threshold, the control circuit controls the marine propulsion device to minimize a difference between the actual heading and the user-desired heading while minimizing the position difference.

Abstract: A system and method is provided for efficiently changing controlled engine speed of a marine internal combustion engine in a marine propulsion system for propelling a marine vessel. The system responds to the operator changing the operator-selected engine speed, from a first-selected engine speed to a second-selected engine speed, by predicting throttle position needed to provide the second-selected engine speed, and providing a feed forward signal moving the throttle to the predicted throttle position, without waiting for a slower responding PID controller and/or overshoot thereof, and concomitant instability or oscillation, and then uses the engine speed control system including any PID controller to maintain engine speed at the second-selected engine speed.

Abstract: A marine fuel system and method includes receiving a fuel level signal from a fuel level sensor for a marine fuel tank on a marine vessel and discriminating between condition A comprising an increase in the true amount of fuel in the fuel tank above a given level, and condition B comprising a transient increase in the level of fuel in the fuel tank above the given level due to vessel movement, which may include movement due to waves, rough water, people moving on the vessel, and so on, while the vessel is stationary at a dock or filling station and being re-fueled. An alert signal is output in response to condition A and not to condition B.

Abstract: Systems and methods for optimizing fuel injection in an internal combustion engine adjust start of fuel injection by calculating whether one of advancing or retarding start of fuel injection will provide a shortest path from a source angle to a destination angle. Based on the source angle and a given injection pulse width and angle increment, it is determined whether fuel injection will overlap with a specified engine event if start of fuel injection is moved in a direction of the shortest path. A control circuit increments start fuel injection in the direction of the shortest path if it is determined that fuel injection will not overlap with the specified engine event, or increments start fuel injection in a direction opposite that of the shortest path if it is determined that fuel injection will overlap with the specified engine event.