In general, the subject matter described in this disclosure can be embodied in a fuel injector that includes an upper housing portion that defines an inlet passage adapted to receive fuel, and a lower housing portion that is attached to the upper housing portion and that defines an injector outlet adapted to dispense fuel. The fuel injector includes an electromagnetic coil assembly that is user removable while the upper housing portion remains attached to the lower housing portion. The fuel injector includes a movable pintle that is biased to a closed position that is adapted to prevent fuel from flowing through the injector outlet, and movable, responsive to magnetic force produced by energizing the electromagnetic coil assembly, to an open position that is adapted to permit fuel to flow through the injector outlet.

An improved apparatus for repairing fuel injector hold-down bolt holes is disclosed. The apparatus can be readily mounted to the passage through which the fuel injector passes via a flange that fits inside the passage and thus generally avoids the need to remove the engine in order to conduct the repairs. The apparatus further provides guides or bushings that allow for the precise alignment of various tools to repair the hold-down bolt hole.

The present disclosure relates to internal combustion engines. Various embodiments thereof may include a fuel injection valve for a combustion engine comprising: a valve body with a cavity; a valve needle movable in the cavity; an actuator assembly to actuate the valve needle. The actuator assembly includes an electro-magnetic coil, a pole piece positioned inside the cavity, and an armature element. The armature element moves within the cavity to move the valve needle in a predetermined direction. A fixing ring abutting the pole piece, fixed to the valve body by means of joining to a circumferential surface of the cavity.

An insert for use with a fuel injector comprises a shaft including a substantially cylindrical configuration defining a shaft cylindrical axis, a shaft radial direction, and a shaft diameter; and a head including a substantially cylindrical configuration defining a head cylindrical axis, a head radial direction, and a head diameter. The shaft and head may be attached to each other, the shaft cylindrical axis and the head cylindrical axis may be parallel to each other, the head diameter may be greater than the shaft diameter, and the shaft cylindrical axis may be spaced away from the head cylindrical axis.

An actuator assembly of a digital inlet valve for a fuel pump adapted to cooperate with an inlet valve member includes an actuator body in which is fixed a coil, a cover closing the body and, a magnetic core arranged in a core guiding bore provided in the actuator body. The magnetic core is slidable along a main axis in order, in use, to close an air gap under the influences of a first compression spring, and of a magnetic field, the core cooperating with the valve member.

An improved apparatus for repairing fuel injector hold-down bolt holes is disclosed. The apparatus can be readily mounted to the passage through which the fuel injector passes via a flange that fits inside the passage and thus generally avoids the need to remove the engine in order to conduct the repairs. The apparatus further provides guides or bushings that allow for the precise alignment of various tools to repair the hold-down bolt hole.

A device and method for adjusting a fuel supply advance angle of a multi-cylinder diesel engine includes a gear chamber, a connecting disc and a fuel pump, wherein the gear chamber and the connecting disc are in the diesel engine, and the fuel pump is at a left end surface outside the gear chamber. A main shaft end of the fuel pump extends into the gear chamber. A right end surface of the connecting disc connects to a timing gear. A right end surface of the timing gear has three penetrating circular-arc waist-shaped holes. Annular sizing blocks are arranged on the waist-shaped holes. A penetrating circular hole is at a tail end of the waist-shaped holes. The circular hole is provided with a T-shaped nut. A support screw is arranged in the T-shaped nut, and the screw head of the support screw is jacked against the annular sizing block.

A device for adjusting a fuel supply advance angle of a multi-cylinder diesel engine includes a gear chamber (3), a connecting disc (5) and a high-pressure fuel pump (2), wherein the gear chamber (3) and the connecting disc (5) are assembled in the diesel engine, and the high-pressure fuel pump (2) is arranged at a left end surface outside the gear chamber. A main shaft end of the high-pressure fuel pump (2) extends into the gear chamber (3) and is connected to the connecting disc (5). A right end surface of the connecting disc (5) is connected to a timing gear (6) of a fuel injection pump. A right end surface of the timing gear (6) of the fuel injection pump is provided with three penetrating circular-arc waist-shaped holes (61) that are away from the center and equally spaced along the circumference direction. Annular sizing blocks (63) are arranged on the waist-shaped holes (61). A penetrating circular hole (68) is arranged at a tail end of at least one of the waist-shaped holes (61) in a counterclockwise direction and away from the waist-shaped hole (61). The circular hole (68) is provided with a T-shaped nut (65), and the axis of the T-shaped nut (65) is in parallel with the end surface of the timing gear (6) of the fuel injection pump. A support screw (67) is arranged in the T-shaped nut (65), and the screw head of the support screw (67) is jacked against the annular sizing block (63). A method for adjusting a fuel supply advance angle of a multi-cylinder diesel engine is also disclosed. The adjusting device and the adjusting method are convenient for adjusting a fuel supply advance angle and therefore have high adjustment precision.

A fuel injector includes a valve member for selectively preventing and permitting flow of fuel through a valve seat by selectively engaging and disengaging the valve seat, an actuator for selectively applying a force to the valve member in order to unseat the valve member from the valve seat, and a return spring which biases the valve member into contact with the valve seat when the actuator is not applying the force to the valve member. A calibration tube is positioned within the fuel tube and holds the return spring in compression so as to set a force on the return spring to achieve a desired dynamic flow of fuel through the fuel injector. The calibration tube includes at least one protrusion extending outward therefrom such that the protrusion engages the fuel tube, thereby creating a spring fit between the calibration tube and the fuel tube.

In general, the subject matter described in this disclosure can be embodied in a fuel injector that includes an upper housing portion that defines an inlet passage adapted to receive fuel, and a lower housing portion that is attached to the upper housing portion and that defines an injector outlet adapted to dispense fuel. The fuel injector includes an electromagnetic coil assembly that is user removable while the upper housing portion remains attached to the lower housing portion. The fuel injector includes a movable pintle that is biased to a closed position that is adapted to prevent fuel from flowing through the injector outlet, and movable, responsive to magnetic force produced by energizing the electromagnetic coil assembly, to an open position that is adapted to permit fuel to flow through the injector outlet.