A system includes an engine and a controller. The engine is capable of multiple operating modes, and each mode has a relatively different fuel ratio such that as the engine is changed from a first operating mode having a first ratio of a first fuel to a second fuel to a second operating mode having a second ratio of the first fuel to the second fuel. The controller is operable to change the engine from one operating mode to another operating mode.

During a pressurization stroke of a high-pressure pump, a cylinder inner wall and a plunger receive a fuel pressure from the pressurization chamber. Meanwhile, an upper housing does not receive the fuel pressure from the pressurization chamber, so that its thickness can be made thin. A cylinder is comprised of a bottom portion, a cylindrical portion and a large-diameter cylindrical portion. When inserting the large-diameter cylindrical portion into a large engaging hole, the bottom portion and the cylindrical portion are not brought into contact with a lower housing. A high liquid-tightness between the bottom portion, the cylindrical portion and a small engaging hole can be ensured.

A cam follower roller device, notably for fuel injection pump of an internal combustion engine, the cam follower roller device comprising a casing, a shaft mounted on the casing and a roller rotatably mounted on the shaft. The casing comprises on its periphery at least four openings made through the thickness of the casing and located in such a way that two openings face one end of the outer cylindrical surface of the roller.

A tool is disclosed for installing a roller tappet in a bore of the cylinder head of an internal combustion engine. The tool includes an elongated body and a connection head arranged at one end of the elongated body and configured to be at least in part inserted into an opening of the roller tappet. The tool further includes at least one reversible constraining element of the connection head to the roller tappet.

A roller lifter includes a lifter body having a cylindrical peripheral wall and a roller rotatably mounted on the lifter body via a shaft member and brought into contact with a cam. The peripheral wall has an outer periphery formed with a sliding surface which is slid on an inner wall of a cylinder. The lifter body has a rotation stopper formed by outwardly protruding a part of the peripheral wall, and an opening formed in another part of the peripheral wall which another part is radially opposed to the rotation stopper. The opening is open so that the rotation stopper oppositely faces the opening.

A mechanical system, comprising a support element, a pin extending along a first axis and comprising two opposite ends, each adapted to be fitted in the support element for radial retention of the pin relative to the first axis, and a roller element movable in rotation relative to the pin around the first axis. The mechanical system includes two ribs resting on either side of the ends for axial retention of the pin along the first axis. The mechanical system can be integrated into either an injection pump or a valve actuator.

Methods and systems are provided for controlling a low pressure pump in port fuel direct injection (PFDI) engines. One method includes, when operating a high pressure pump in a default pressure mode, pulsing the low pressure pump when pressure in a high pressure fuel rail decreases below a threshold. The method further includes, when operating the high pressure pump in a variable pressure mode, pulsing the low pressure pump based on presence of fuel vapor at an inlet of the high pressure pump.

A method for controlling a high-pressure pump for the injection of fuel into a combustion engine, the high-pressure pump being connected to a camshaft of the combustion engine, wherein the high-pressure pump is controlled in a camshaft-synchronous manner by ascertaining an angular offset between the flank positions of a camshaft pulse-generating wheel and a predefinable point above the bottom dead center of a cam of the high-pressure pump on the camshaft.

A valve device for switching or metering a fluid includes a housing, a flow channel defined by the housing, and a valve body arranged in the flow channel. The valve body has a sealing section which contacts a housing-side sealing seat when the valve device is closed. The sealing section at least slightly protrudes beyond a surface of the valve body facing the sealing seat.

A fuel injection control device is adapted for a fuel injection system including an injector and a high-pressure pump that raises pressure of fuel and supplies the fuel to the injector. The fuel injection control device includes a selecting unit for selecting by which one of full lift injection and partial injection to inject fuel, and a pump control unit for controlling operation of the high-pressure pump such that a pressure of fuel supplied to the injector coincides with a target pressure. The selecting unit selects the partial injection when a required injection quantity of fuel is equal to or smaller than a partial maximum injection quantity. A fuel injection system includes the fuel injection control device, the injector, and the high-pressure pump.