A pump includes a pump body having an admission valve movable therein to alternately block and unblock a valve seat to connect a low pressure space to a pumping chamber. A control valve is positioned fluidly between a control chamber and the low pressure space, and moves between a closed position where the control chamber receives high pressure for hydraulically actuating the admission valve, and an open position where the control chamber is connected to the low pressure space to enable closing of the admission valve. The pilot actuation of the admission valve produces a greater travel distance and efficiency than what might be available with certain other actuating mechanisms.

A fuel injector includes an injector body, and a stack within the injector body, and having a nozzle supply passage therein. The stack includes a solenoid assembly having a solenoid housing piece with a fuel bore formed therein that includes a segment of the nozzle supply passage. The solenoid housing piece includes a solenoid housing material in a base state, and a solenoid housing material in a residual compressive stressed state, with the fuel bore being formed by the solenoid housing material in the residual compressive stressed state. Residual stresses may be imparted by ballizing, nitriding, carburizing, autofrettage, or still another technique.

A method comprises determining either the coefficient for the equation relating the injection timing distance of a bushing to the angle of rotation of a shaft of an engine, or the desired effective injection stroke reduction; and calculating at least one of the following: the modified injection timing distance by multiplying the desired angle of retardation of the injection timing by the coefficient and adding that product to the original injection timing distance of the bushing, and the modified injection duration distance by subtracting the desired effective injection stroke reduction from the original injection duration distance.

The hydraulic injection system (100) with cam comprises an injection valve (50) housed in a tubular injection nozzle (54), a gap being formed between a valve stem (51) of said valve (50) and the inner surface of the tubular injection nozzle (54) to allow an injectable fluid (58) coming from pressurizing means (10) to flow, while a receiver piston (62) fixed with respect to said valve (50) receives on the one hand the pressure of the injectable fluid (58) to hold said valve (50) closed, and on the other hand, the pressure of a hydraulic fluid (60) to open said valve (50), an injection cam (67) being capable to move said receiver piston (62) via an emitter piston (69) and said hydraulic fluid (60).

A fuel injection method includes applying a first method current to close a spill valve according to a first method, applying a control valve current to open a control valve, and discontinuing the application of the control valve current to thereby cause the control valve to close. The method also includes applying a second method current to maintain the spill valve closed according to a second method and detecting a timing of a closing of the control valve while applying the second method current according to the second method, the second method being different than the first method.

A method of injecting fuel with a fuel injector includes applying a spill valve current to close a spill valve and applying a control valve current to move a control valve to an injection position. The method also includes discontinuing the application of the spill valve current to open the spill valve and preventing a return of the control valve to a non-injection position while detecting a timing when the spill valve opens.

A nozzle assembly for a fuel injector includes an injector housing having a casing and a stack within the casing, an outlet check movable within a nozzle cavity in the injector housing, and having a stop positioned within a stop cavity. A clearance is formed between the outlet check and the injector housing and fluidly connects a spring cavity to a stop cavity, and an anti-cavitation vent is formed in the stack and fluidly connects the spring cavity to a low pressure space. The anti-cavitation vent limits pressure changes in the spring cavity during fuel injection such that production of cavitation bubbles in the spring cavity is limited.

A nozzle assembly for a fuel injector includes an injector housing having a casing and a stack within the casing, an outlet check movable within a nozzle cavity in the injector housing, and having a stop positioned within a stop cavity. A clearance is formed between the outlet check and the injector housing and fluidly connects a spring cavity to a stop cavity, and an anti-cavitation vent is formed in the stack and fluidly connects the spring cavity to a low pressure space. The anti-cavitation vent limits pressure changes in the spring cavity during fuel injection such that production of cavitation bubbles in the spring cavity is limited.

A method of improving fuel delivery in an engine having one or more cylinders that are over-fueled related to other cylinders, such as a D-EGR engine. The fueling system uses a mechanical fuel pump, which is cam-driven. The cam has lobes corresponding to the desired displacement for each cylinder. The lobe corresponding to the over-fueled cylinder is shaped differently, such that the filling stroke of the pump is increased.

A fuel system is disclosed for use with an engine. The fuel system may have a common rail, a first type of fuel injector fluidly connected to the common rail, and a second type of fuel injector fluidly connected to the common rail. The second type of fuel injector may include a pumping portion having a bore formed therein, and a plunger reciprocatingly disposed in the bore. The second type of fuel injector may also include an accumulator portion fluidly connected to the common rail and configured to receive fuel pushed from the bore of the pumping portion by the plunger, a nozzle portion, and a valve portion fluidly connecting the pumping, nozzle, and accumulator portions.