A multi-fuel rail apparatus for an internal combustion engine communicates fuel from 10 a first fuel source and a second fuel source to a plurality of fuel injectors. Each fuel injector receives fuel from the multi-fuel rail apparatus through a branch connection for each fuel. The multi fuel rail apparatus has a first elongate member including a first longitudinal bore spaced apart from a second longitudinal bore and first and second fuel inlets for fluidly communicating first and second fuels into the first and 15 second longitudinal bores respectively. There is a branch connecting structure for each fuel injector along the first elongate member for fluidly connecting the first and second longitudinal bores with respective branch connections from respective fuel injectors.

A system for exchanging of different fuels that can be used for operation of an engine. The system includes a fuel exchange unit, a control and an exchange return conduit. The fuel exchange unit is configured to deliver a first fuel at pressure into the injections system given a switched-off engine, in order to replace a second fuel, which is located in the injection system, with the first fuel. A fuel delivery system includes a media converter which includes a deflectable element. The media converter is driven by a drive unit via the fluid by way of the fluid being able to be led at a varying pressure to the media transformer via a first feed conduit, and is configured to deliver the fuel via a pumping effect.

A fuel supply valve for a slurry fuel injector valve, the fuel supply valve comprising: a fuel inlet for fluid communication with a slurry fuel reservoir; a fuel outlet for fluid communication with a nozzle of the fuel injector valve; a pump chamber port for fluid communication with a pump chamber of the fuel injector valve; and a valve gate moveable between a first position, at which the fuel inlet is in fluid communication along a first slurry fuel flow path with the pump chamber port, and a second position, at which the fuel outlet is in fluid communication along a second slurry fuel flow path with the pump chamber port; wherein the valve gate is operable with a valve actuation liquid from an engine.

Disclosed is a slurry fuel injector valve, comprising: a fuel outlet valve through which slurry fuel is able to exit the slurry fuel injector valve towards a combustion chamber of an engine; a pump cavity; a pump element that divides the pump cavity into a pump chamber and an actuation chamber; a fuel conduit through which slurry fuel is flowable from the pump chamber to the fuel outlet valve; and an actuation fluid conduit through which actuation fluid is flowable from the actuation chamber to the fuel outlet valve.

Disclosed is a valve needle for a needle valve of a slurry fuel injector valve, the valve needle comprising: a tip for abutting a needle valve seat of the needle valve; a sealing portion for location in a bore of the needle valve; and a fuel chamber portion between the tip and the sealing portion, wherein the fuel chamber portion is for location in a needle fuel chamber of the needle valve; wherein a surface of the sealing portion of the valve needle comprises at least one groove and wherein at least part of the or each groove extends in a direction that is non-perpendicular to an axial direction of the valve needle.

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.

An internal combustion engine system is described herein. The internal combustion engine system uses one or more fuels that may be hydrophilic. The system uses a water measuring sensor to determine the concentration of water in the hydrophilic fuel. To meet power demands, the system uses the measured water concentration to modify data stored in a fuel map. The fuel map provides a controller the pump speeds and mixing ratio of the fuels for a given power level. The system receives that data and modifies it based on the measured concentration of water.

Methods and systems are provided for an engine to infer fuel temperature from a measured rate of change in a pressure of a fuel passage between a low pressure fuel pump and a high pressure fuel pump during certain operating conditions, including when the low pressure fuel pump is switched off. The operation of the low pressure fuel pump may be adjusted responsively to a change in the inferred fuel temperature.

A flow limiting valve, comprising a valve body adjustable between a closed position and an open position, wherein in the open position a flow channel for a conveying fluid is opened in the flow limiting valve and in the closed position the flow channel is closed, whereby the adjustment of the valve body is subject to conveying fluid pressure; wherein a control valve is integrated into a housing of the flow limiting valve through which the valve body is adjustable between open and closed positions, regardless of the conveying fluid.

An internal combustion engine has both a primary fuel system and a starting fuel intake assembly. The primary fuel system and the starting fuel intake assembly provide separate flow paths to a common chamber of the internal combustion engine. An external starting fuel source is fluidly connectable with the starting fuel intake assembly of the internal combustion engine, for instance when exposed to a low ambient temperature environment. The internal combustion engine is started while a starting fuel is flowing into a combustion chamber for the internal combustion engine. A primary fuel may also be flowing into the combustion chamber at this time. After the primary fuel is being consistently ignited in the combustion chamber, the flow of starting fuel to the combustion chamber may be terminated and the external starting fuel source may be fluidly disconnected from the starting fuel intake assembly of the internal combustion engine.