A vehicle and a fuel system for a vehicle are provided. The fuel system has a fuel tank, a fuel fill inlet fluidly connected to the fuel tank to receive fuel dispensed from an external fuel supply device, and a recirculation line with a first end fluidly connected to the fuel fill inlet and a second end fluidly connected to the fuel tank. An ejector is positioned within the recirculation line. A valve fluidly connects the ejector to the fuel tank via a drain line. A method of fueling a vehicle is also provided.

A supplemental fuel system includes a fuel mixer. The fuel mixer includes a nozzle and a stem. The nozzle is configured to be positioned within a conduit of an air supply system for a compression-ignition engine. The nozzle has a body defining a first inlet positioned at a first nozzle end thereof, an outlet positioned at a second nozzle end thereof, a second inlet positioned between the first nozzle end and the second nozzle end, and a nozzle passage extending from the first nozzle end to the second nozzle end that is configured to receive air flowing through the conduit. The stem has a first stem end interfacing with the second inlet. The stem is configured to extend through a wall of the conduit such that a second stem end is positioned outside of the conduit.

A gas fuel supply system for supplying the gas fuel via an opening of an intake supply pipe that is connected to a combustion chamber in an engine operable in each of a gas fuel combustion mode and an oil fuel combustion mode includes: the gas fuel supply valve for regulating an amount of the gas fuel, the gas fuel supply valve having plural gas supply holes, from which the gas fuel is fed in a direction toward the opening when the valve is opened; and an opening regulation valve provided between the gas fuel supply valve and the opening and having an opening hole, an opening area of which can be regulated. The gas fuel supply system is configured that extended axes of all the gas supply holes pass through the fully opened opening hole.

Various methods and systems are provided for venting fuel lines in a dual-fuel engine. In one example, a method may include in response to an engine shut-down request, venting fuel lines to remove hydrogen from the fuel lines.

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 gas supply system, having a gas regulating station for supplying an engine with gaseous fuel and a double-walled gas line extending from the gas regulating station to the engine, which comprises an inner and an outer pipe, in a gas fuel operating mode the inner pipe is flowed through by the gaseous fuel towards an engine-side end of the double-walled gas line, an inert gas purging line, and a first shut-off valve assigned to the inert gas purging line. In a purging mode inert gas can be fed to the outer pipe at the gas regulating station-side, which inert gas flows through the outer pipe in the direction of the engine-side end of the double-walled gas line, where it passes into the inner pipe and flows via the inner pipe towards the gas regulating station-side end of the double-walled gas line.

A dual-fuel supply system (100) for direct injection for engines of heavy vehicles, comprising: a supply line of a combustible liquid (160); a supply line of a combustible gas (170); a plurality of injectors (150) in fluid communication with the supply line of the combustible liquid (160) and with the supply line of the combustible gas (170); a pressure regulator device (1) for regulating the combustible gas; an electronic control unit (ECU) configured to control the supply of combustible liquid and of the combustible gas to the injectors (150), the electronic control unit (ECU) being configured to control the pressure regulator device (1) to track a reference pressure (p.sub.target) according to a feedback logic.

A supplemental fuel system includes a supplemental fuel tank, an electronic valve, a voltage sensor, and a controller. The supplemental fuel tank is configured to store a supplemental fuel configured to supplement a primary fuel used by an engine. The electronic valve is configured to be positioned between the supplemental fuel tank and an air supply system for the engine. The voltage sensor is configured to acquire voltage data from a power supply indicative of a voltage of the power supply. The power supply is configured to receive power from an alternator driven by the engine. The controller is configured to control the electronic valve such that the electronic valve is (i) closed in response to the voltage being less than a voltage threshold and (ii) open or openable in response to the voltage being greater than the voltage threshold.

A supplemental fuel system includes a supplemental fuel tank, a first pressure regulator, a second pressure regulator, and a nozzle. The supplemental fuel tank is configured to store a supplemental fuel at a first pressure. The first pressure regulator is configured to reduce the first pressure of the supplemental fuel received from the supplemental fuel tank to a second pressure. The second pressure regulator is configured to reduce the second pressure of the supplemental fuel received from the first pressure regulator to a third pressure. The nozzle is configured to be positioned (i) downstream of the second pressure regulator and (ii) within a conduit of an air supply system for the compression-ignition engine. The nozzle is configured to receive a flow of the supplemental fuel and provide the supplemental fuel to air flowing though the conduit.

A supplemental fuel system for a machine having a compression-ignition engine includes an air intake tube. The air intake tube has a first end configured to interface with an air cleaner of an air supply system that provides air to the compression-ignition engine, a second end configured to interface with a compressor of a turbocharger of the air supply system, and a sidewall extending between the first end and the second end. The sidewall includes a fuel interface configured to facilitate providing a supplemental fuel into the air intake tube to mix with the air upstream of the compressor of the turbocharger.