A fuel supply valve for a slurry fuel injector valve comprises a fuel inlet in fluid communication with a slurry fuel reservoir. A fuel outlet is in fluid communication with a nozzle of the fuel injector valve. A pump chamber port is in fluid communication with a pump chamber of the fuel injector valve. A valve gate is moveable between a first position wherein the fuel inlet is in fluid communication along a first slurry fuel flow path with the pump chamber port and a second position wherein the fuel outlet is in fluid communication along a second slurry fuel flow path with the pump chamber port. Wherein the valve gate is arranged to not substantially exert a force opposing a flow on the slurry fuel into the valve chamber when the valve gate moves between the second position and the first position and/or between the first position and the second position.

The present invention relates to a fuel injection arrangement for a diesel type engine configured to use carbonaceous aqueous slurry fuels. The fuel injection arrangement includes an injector nozzle for injecting fuel into a combustion chamber; a pump chamber housing a fuel pumping element for generating a pressurised fuel flow to the injector nozzle along an injection path between the pumping element and the injector nozzle; and a check valve connected to a fuel supply for regulating and supplying fuel to the injection path via a check valve outlet. A region immediately downstream of the check valve outlet defines an outlet region and the check valve is arranged to expose the outlet region to the pressurised fuel flow to facilitate flushing of the outlet region during fuel flow between the pumping element and the injector nozzle.

There is disclosed a solenoid valve for a fuel injection system, in which solenoid valve a closing element which interacts with a valve seat in order to close and open the solenoid valve is actuated by a control pin, the control pin being formed by way of a solenoid plunger. Furthermore, a high pressure fuel pump is disclosed which has a solenoid valve of this type.

A high-pressure fuel pump includes a housing including a chamber, an inlet flow passage to draw fuel into the chamber, and a discharge flow passage to discharge fuel out of the chamber. The high-pressure fuel pump further includes a piston disposed in the housing and configured to compress fuel, a sleeve coupled to the housing and configured to support the piston and form a space for storing fuel, a discharge valve disposed in the discharge flow passage and configured to open when a pressure of fuel stored in the chamber is equal to or greater than a first pressure, and a pressure relief valve disposed in a relief flow passage that communicates with the discharge flow passage and the space. The pressure relief valve is configured to open when a pressure of fuel supplied into the relief flow passage is equal to or greater than a second pressure.

A fuel system is provided that includes a boost stage, a positive displacement pump and a first bypass valve configured to bypass fuel to one of the boost stage and the positive displacement pump. A second bypass valve is configured to bypass fuel to the other of boost stage and the positive displacement pump.

A pump unit has an inlet valve, an outlet valve, a supply line for supplying fuel, a pumping chamber, and a plunger for pressurizing fuel in the pumping chamber. The inlet valve includes an inlet valve member movable between a first position and a second position. The inlet valve member has an aperture formed therein. The aperture provides a first fluid pathway between the pumping chamber and the supply line when the inlet valve member is in its first position, and the aperture provides a second fluid pathway between the pumping chamber and the outlet valve when the inlet valve member is in its second position.

There is disclosed a solenoid valve for a fuel injection system, in which solenoid valve a closing element which interacts with a valve seat in order to close and open the solenoid valve is actuated by a control pin, the control pin being formed by way of a solenoid plunger. Furthermore, a high pressure fuel pump is disclosed which has a solenoid valve of this type.