Abstract: A system and method for diagnosing output power of an internal combustion engine includes means for diagnosing potential causes of low engine output power or torque and means for estimating actual engine output power or torque. In a preferred embodiment of the diagnosis of engine output power, low engine output power is first investigated for authenticity to verify whether a low engine output power condition exists. If one exists, a zero fueling engine cranking test is conducted to determine whether relative compression values for each of the cylinders are within specification, and any problems associated therewith are corrected by service personnel. If the low engine output power problem is not corrected in accordance with the engine cranking test, a snap-throttle cylinder balancing test is conducted to balance the relative power contribution from each cylinder.

Abstract: An improved method and system for automatically continuously replacing an engine's used lubricating oil with fresh lubricating oil throughout operation based on engine operating conditions is disclosed. The present system includes an injection control device for injecting small amounts of used lube oil into the engine's fuel system and an auxiliary flow control device for directing controlled quantities of fresh oil into the engine's lube oil system. An electronic controller is provided to vary the amount of used lube oil injected into the oil system based on the severity of engine operation. The process periodically determines an engine operating severity value, i.e. fuel consumption value, for an interval of engine operation and calculates a base line quantity of oil for injection based on the current fuel consumption of the engine during the current interval.

Abstract: An improved method and system for automatically continuously replacing an engine's used lubricating oil with fresh lubricating oil throughout operation based on engine operating conditions is disclosed. The present system includes an lube oil replacement pump system operable in a replacement mode for injecting small amounts of used lube oil into the engine's fuel system and directing controlled quantities of fresh oil into the engine's lube oil system to replace the removed oil. The process periodically determines an engine operating severity value, i.e. fuel consumption value, for an interval of engine operation and calculates a base line quantity of oil for injection based on the current fuel consumption of the engine during the current interval. The lube oil replacement pump may also be operated in a makeup mode for adding quantities of fresh oil to the engine lube oil sump to compensate for oil consumed by the engine.

Abstract: An improved system for automatically continuously replacing an engine's used lubricating oil with fresh lubricating oil throughout operation based on engine operating conditions is disclosed. The present system includes an intermittent injection control device for intermittently injecting small amounts of used lube oil into the engine's fuel system. An electronic controller is provided to vary the amount of used lube oil injected into the oil system based on the severity of engine operation. The system periodically determines an engine operating severity value, i.e. fuel consumption value, for an interval of engine operation and calculates a base line quantity of oil for injection based on the current fuel consumption of the engine during the current interval. The system may also include an auxiliary flow control device for directing controlled quantities of fresh oil into the engine's lube oil system for maintaining the engine's oil sump at a proper level.

Abstract: A load driver system for integrally controlling the flow of current through a number of inductive loads of an internal combustion engine, particularly the flow of current through a fuel injector solenoid and an engine brake solenoid during the operation of an engine cylinder, is provided. In one embodiment of the load driver system, a single multiplexed high side driver is connected to inputs of both solenoids, and separate low side drivers are connected to outputs of each of the solenoids. In an alternative embodiment, separate high side drivers are connected to inputs of each of the solenoids, and a single multiplexed low side driver is connected to the outputs of the solenoids.

Abstract: An improved method and system for automatically continuously replacing an engine's used lubricating oil with fresh lubricating oil throughout operation based on engine operating conditions is disclosed. The present system includes an injection control device for injecting small amounts of used lube oil into the engine's fuel system and an auxiliary flow control device for directing controlled quantities of fresh oil into the engine's lube oil system. An electronic controller is provided to vary the amount of used lube oil injected into the oil system based on the severity of engine operation. The process periodically determines an engine operating severity value, i.e. fuel consumption value, for an interval of engine operation and calculates a base line quantity of oil for injection based on the current fuel consumption of the engine during the current interval.

Abstract: A system for controlling the temperature of recirculated exhaust gas supplied to an internal combustion engine is provided. In one embodiment, the system includes a heat exchanger having the recirculated exhaust gas flowing therethrough and further having coolant fluid flowing therethrough. A control valve is disposed within the flow path of the coolant fluid, and the valve position is modulated to vary the rate of coolant fluid flow through the heat exchanger, thereby controlling the temperature of the recirculated exhaust gas supplied by the heat exchanger. In another embodiment, the heat exchanger defines a number of exhaust gas flow passages therethrough and a number of gas flow control valves are disposed between the exhaust gas inlet of the heat exchanger and the number of exhaust gas flow passages.

Abstract: A control system for controlling fueling and/or timing of a fuel injector in an internal combustion engine. Fuel injection is controlled based upon the recent operating history of the engine. In particular, the difference between the instantaneous speed and the average speed over a previous predetermined period are compared and the difference is utilized in determining a control variable which in turn can be used for selecting fueling and/or timing values. The difference between the instantaneous fueling and the average fueling over a predetermined period can also be used in selecting the control variable. The fuel injector fueling and/or timing is determined utilizing fueling and/or timing values from at least two maps, with the control variable determining the proportions of the timing/fueling valves to be utilized in determining commanded timing/fueling.

Abstract: The present invention is directed to open nozzle type unit fuel injectors, and more specifically to an improved lower plunger and cup design of an open nozzle unit injector to minimize trapped volume and reduce unburned hydrocarbons in vehicle emissions. The lower plunger includes at least a major and a minor diameter sections with the minor diameter section extending within a bore of said cup at least partially between the fully advanced and retracted positions of the plunger. Moreover, the labyrinth flow area between the cup bore and the minor diameter section of the plunger is designed to reduce the trapped volume of fuel that results in the advanced plunger position while reducing sensitivity to fuel metering in the retracted plunger position. In one embodiment, the cup bore and minor diameter section are stepped. In another, both the bore and the minor diameter section are tapered. In yet another embodiment, only the cup bore is modified.

Abstract: An aftercooler housing (26) is made of lightweight sheet material which is assembled with an aftercooler core (44) so that the core (44) reinforces the housing. Housing (26) can be constructed from a sheet of suitable metal, plastic, fiberglass which extends around the core to provide an open ended configuration. End walls (36, 38) enclose the housing, and wall (36) supports both an air inlet port (24) as well as coolant fluid inlet and outlet ports (62, 64). Top wall (28) of the housing is tapered downwardly from wall (36) to wall (38) to provide a tapered air inlet chamber for the aftercooler. Reinforcing sections (58) are provided on the sidewall of the housing adjacent the engine, and cross tie members (72, 78) pass from the remaining sidewall of the housing through the housing to the reinforcing sections to transfer some of the load on the housing to the reinforcing sections.

Abstract: The disclosure illustrates a cooling system for a turbocharged diesel engine having an aftercooler and an oil cooler. The cooling system is defined by two flow loops, one for the engine and the other for cooling purposes. An engine driven pump circulates a coolant through the engine block and cylinder heads. The pump also circulates coolant through the cooling loop which includes the engine oil cooler immediately upstream of a radiator and bypass line. The aftercooler is downstream of the radiator and bypass line. Placement of the oil cooler ahead of the radiator and bypass line produces a higher temperature potential which permits a reduction in radiator size in addition to other benefits. A flow control logic system embodied in a dual thermostat arrangement ahead of the radiator and bypass line minimizes mixing of bypass flow with radiator flow and reduces radiator flow rates to permit low aftercooler temperatures that hithertofore have not been achievable.

Abstract: A system is provided for regulating the oil temperature of a diesel engine while the latter is in various operating modes. The engine includes a heat exchange unit through which a heat exchange medium circulates and while the engine is in certain operating modes, the system directs the oil flow through the heat exchange unit so that the oil is either heated or cooled by the circulating heat exchange medium. The system includes a valve housing provided with a cavity having an oil inlet port, first oil outlet ports connected to the heat exchange unit, and a second oil outlet port connected to a passage for bypassing the unit. Disposed within the cavity is an adjustable element for effecting interconnection between the inlet port and a selected outlet port. Adjustment of the valve element within the cavity is determined by the oil temperature during predetermined operating modes of the engine.

Abstract: The disclosure illustrates a means for automatically controlling the operation of a cylinder deactivating system in a multicylinder compression ignition engine which system is intended to increase the load on the cylinders that have not been deactivated. The control means is responsive to coolant pump output pressure which varies directly as engine rpm varies. The cylinder deactivating system functions either by cutting off the flow of fuel to the injector for each deactivated cylinder or cylinders or by actuating an engine brake system. The control means automatically stops the operation of the cylinder deactivating system when engine rpm increases to the point that the coolant pump output pressure exceeds a threshold level. This prevents any possibility of injector scuffing or loss of power at higher rpm.

Abstract: A "snap action" early warning bypass valve assembly (2), responsive to fluid pressure differentials and/or low pressure, functions as both an electrical switch to provide an indication of low pressure or an impending fluid bypass and as a mechanical valve to actually implement the fluid bypass. The valve assembly includes a sealing piston (24, 124) supported by a retaining surface (18, 106) having a central bore (22, 110) formed therein. The sealing piston (24, 124) contains a bypass aperture (36) and is shaped to present a differential sealing area (39) to fluid circulating within the central bore (22, 110). A spring-biased bypass disc (42, 134) covers the bypass aperture (36) to present a central sealing area (45) to fluid within the central bore (22,110). A first pressure differential acting simultaneously across the central (45) and differential (39) sealing areas forces piston (24) into contact with an electrical terminal pin (48,92,126) thus energizing an alarm circuit (48-64,90).

Abstract: A "snap action" early warning bypass valve assembly (2) responsive to fluid pressure differentials functions as both an electrical switch to provide an indication at impending fluid bypass and as a mechanical valve to actually implement the fluid bypass. The valve assembly includes a piston (24) supported by a retaining surface (18,106) having a central bore (22,110) formed therein. The piston (24) contains a bypass aperture (36) and is shaped to present a differential sealing area (39) to fluid circulating within the central bore (22,110). A spring-biased bypass disc (42) covers the bypass aperture (36) to present a central sealing area (45) to fluid within the central bore (22,110). A first pressure differential acting simultaneously across the central (45) and differential (39) sealing areas forces piston (24) into contact with an electrical terminal pin (48,92), thus energizing an alarm circuit (48-64,90).