An internal combustion engine system includes an engine head, a pressurized fuel supply conduit, and a fuel return conduit. Fuel injectors are positioned in fuel injector bores in the engine head, and each include an intensifier plunger, a nozzle check, an injection control valve, and an intensifier control valve. Fuel recovery fittings are coupled to the plurality of fuel injectors and each fluidly connect an actuation fuel outlet in one of the fuel injectors to the fuel return conduit.

An internal combustion engine system includes an engine head, a pressurized fuel supply conduit, and a fuel return conduit. Fuel injectors are positioned in fuel injector bores in the engine head, and each include an intensifier plunger, a nozzle check, an injection control valve, and an intensifier control valve. Fuel recovery fittings are coupled to the plurality of fuel injectors and each fluidly connect an actuation fuel outlet in one of the fuel injectors to the fuel return conduit.

The teachings of the present disclosure describe an injector having an injector housing, an actuator, and a nozzle needle, wherein the actuator is arranged in an actuator space of the injector housing. The injector may include a control piston bore in the injector housing, in which a control piston is arranged, a leakage pin bore between the actuator space and the control piston bore, and a leakage pin coupling the control piston to the actuator, the leakage pin arranged in the leakage pin bore. The control piston may be hydraulically connected to the nozzle needle in order to open or close an outlet opening of the injector housing. The injector may include a high pressure line configured to convey a fuel under pressure to the nozzle needle and a feedline in the injector housing connecting the leakage pin bore to the high pressure line.

The present disclosure relates to an injection valve comprising an injector body, a needle body, a control space, a control valve, and a piezoelectric actuator. The injector body has a recess and a fluid inflow and a fluid outflow. The needle body is arranged axially movably in the recess of the injector body and suppresses a fluid flow through an injection opening of the injector body in a closed position of the needle body and otherwise releases it. The control space is disposed in the recess between the fluid inflow and the fluid outflow. The control valve may be arranged in the control space to suppress a fluid flow between the control space and the fluid outflow in a closed position of the valve body and to otherwise release it. The piezoelectric actuator may be coupled mechanically to the control valve via a first transmitter for opening the control valve.