A fuel supply device that supplies fuel from an external tank to an engine includes a fuel injection, an internal tank, a first pipe, a second pipe, a first pump, a fuel supply quantity detection device, and a control device. The internal tank stores fuel to be delivered to the fuel injection device. The first pipe is linked to the internal tank and delivers fuel from the external tank to the internal tank. The second pipe is linked to the fuel injection device and delivers fuel from the internal tank to the fuel injection device. The fuel supply quantity detection device is attached to the first pipe and detects a quantity of fuel supplied from the external tank via the first pipe to the internal tank. The control device implements a predetermined control when the quantity of fuel detected by the fuel supply quantity detection device is below a threshold.

A coupler for translating a rotational force, including first and second rotational elements. The first rotational element defines a first pocket. The second rotational element is in axial alignment therewith and defines a second pocket facing the first pocket. The first pocket and the second pocket define a dampening chamber therebetween that varies in volume based on the overlap thereof. A fluid is positioned in the dampening chamber. A portion of the fluid is dispelled from the dampening chamber when the first rotational element rotates relative to the second rotational element and decreases the volume of the dampening chamber.

A coupler for translating a rotational force, including first and second rotational elements. The first rotational element defines a first pocket. The second rotational element is in axial alignment therewith and defines a second pocket facing the first pocket. The first pocket and the second pocket define a dampening chamber therebetween that varies in volume based on the overlap thereof. A fluid is positioned in the dampening chamber. A portion of the fluid is dispelled from the dampening chamber when the first rotational element rotates relative to the second rotational element and decreases the volume of the dampening chamber.

A plug-in pump for a common-rail system has a pump housing having a cylinder formed therein and a piston guided in the cylinder, a fuel inlet, and a fuel outlet. The pump housing also includes a plug-in section for inserting the pump housing into an opening of an engine component, and a flange that delimits the plug-in section, for fastening the pump housing to the engine component. To cool the plug-in pump, the pump housing has at least one flow duct with a separate fluid inlet and a separate fluid outlet. The fluid inlet is connectable to a fluid-discharging line of the internal combustion engine, and the fluid outlet is connectable to a fluid-receiving line of the internal combustion engine.

Methods and systems are provided for adjusting operation of an internal combustion engine configured for dual fuel injection from a single fuel rail. In one example, a method may include directing fuel from a common high pressure fuel rail to one or more of a direct injector and a port injector, wherein each of the direct injector and port injector may be coupled to a cylinder of an engine. The flow of fuel to the direct injector and port injector from the single fuel rail is mediated by a flow selection valve.

A fuel supply system has a pressure chamber which communicates with a fuel gallery. The pressure chamber receives the fuel from the feed pump or the returned fuel from the fuel gallery. The fuel in the pressure chamber receives heat energy from the engine E so that the fuel is brought into gas-liquid phase. A volume change of the fuel in liquid phase in the fuel gallery can be compensated by a volume change of the fuel in gas phase or gas-liquid phase in the pressure chamber. Thus, the pressure pulsation in the fuel gallery is absorbed in the pressure chamber.

An engine is provided with various enhanced features. For example, a 2-stroke diesel engine has a porting design that enhances the efficiency of a scavenging event. In specific embodiments, a four-piece piston is positioned in each cylinder of the engine. The four-piece piston includes a bowl, a ring retainer, a skirt, and a wrist-pin bearing. In various embodiments, fuel pumps are coupled to fuel channels or high-pressure lines to provide a constant and equal high-pressure fuel supply to engine cylinders. In more specific embodiments, the length of each of the high-pressure lines is the same. In certain specific embodiments, complimentary screws form a supercharger that further improves engine efficiency by providing high-pressure intake air to the porting process.

In a support structure of a direct fuel injection valve capable of supporting a fuel injection valve stably for a long period of time, a valve housing is made of a metal and is provided with a first load bearing portion which is to be supported by an engine in an axial direction of the valve housing, a rear end portion of the fixed core is provided with a second load bearing portion which is to be supported by a resilient holding member in the axial direction, and the first and second load bearing portions are held between the engine and the resilient holding members with a forward set load applied to the resilient holding member by a fuel distribution pipe fitted to a fuel inlet tube and fixed to the engine.

Various methods are thus provided for identifying degradation in a fuel system. In one embodiment, a method of operating a fuel system comprises applying a pulse to a fuel pump responsive to detecting that lift pump pressure corresponds to a fuel vapor pressure, ceasing application of the pulse responsive to detecting that the lift pump pressure corresponds to a relief setpoint pressure, and indicating degradation in the fuel system if the detected lift pump pressure deviates from an expected fuel rail pressure, including distinguishing among degradation in the fuel pump, a lower pressure fuel pressure sensor, a fuel rail pressure sensor, and a pressure relief valve.

An engine device including a common rail configured to store, at a high pressure, a fuel supplied by a fuel feed pump. The common rail includes a pressure reducing valve configured to discharge the fuel in the common rail to a fuel return pipe. The fuel return pipe extends from the pressure reducing valve to a position higher than the pressure reducing valve, and then extends to a position lower than the pressure reducing valve.