The present invention relates to a fuel system for a combustion engine, the fuel system comprising a low-pressure circuit comprising at least one fuel tank, at least one low-pressure fuel pump, a first fuel filter and a second fuel filter which is arranged downstream of the first fuel pump, and a high-pressure circuit comprising a high-pressure fuel pump. The high-pressure fuel pump comprises means to suck fuel from the low-pressure circuit and in case of failure in the at least one low-pressure fuel pump, to suck fuel from the low-pressure circuit and the fuel is arranged to by-pass the at least one low-pressure fuel pump and optionally, at least one of the first or second fuel filters, via at least one by-pass pipe comprising a check valve that prevents the flow of fuel back to the fuel tank.

A no filter no run (NFNR) fluid filter and fluid filter assembly are provided. The NFNR fluid filter assembly includes a fluid filter, a filter head or filter housing, and a bypass flow path. The by-pass flow path may be sealed off when a compliant filter is installed (a filter without a bypass seal), fluid may flow to the bypass flow path.

A valve arrangement includes a valve shaft having a fluid flow bore, and valve gear projections or teeth projecting from the valve shaft, constructed and arranged to receive a force to rotate the valve shaft. The valve arrangement can be used in a filter assembly having cartridge projections such as gear teeth to mesh with the teeth on the valve gear.

The disclosure relates to a fuel filter assembly, a filter element, and a method of draining water from a fuel filter assembly. The fuel filter assembly comprises a filter element with a water collecting space; the filter element being connected to a fuel pipe for feeding an upstream side of the filter element with fuel and for providing filtered fuel from a downstream side of the filter element to a combustion engine or parts thereof; a fuel pump arranged downstream from the filter element, wherein the fuel pump can be operated in a first mode for drawing fuel through the filter element and in a second, reverse mode for feeding fuel back to the filter element; a one-way fuel valve arranged upstream of the filter element allowing for flow towards the upstream side of the filter element; a pressure-actuated one-way drain valve in communication with the water collecting space.

A filter element may include a tubular element defining an internal space, and a retainer element associated with a first end of the tubular element, wherein the retainer element is configured to be coupled to a first housing. The filter element may also include a valve seat member in the internal space. The valve seat member may include a valve seat aperture configured to provide a fluid seal with a valve poppet. The filter element may further include first and second end caps associated with ends of the tubular element. The filter element may also include filter media around the tubular element, and the second end cap may be configured to provide a fluid seal between the filter element and a drain passage in a second housing, such that as the filter element is separated from the second housing, fluid flows from the filter element into the drain passage.

A valve arrangement includes a valve shaft having a fluid flow bore, and valve gear projections or teeth projecting from the valve shaft, constructed and arranged to receive a force to rotate the valve shaft. The valve arrangement can be used in a filter assembly having cartridge projections such as gear teeth to mesh with the teeth on the valve gear.

A fluid filter mountable on a connection flange having a central stand pipe, and having an exchangeable filter insert. The insert has a hollow cylindrical filter material body with two end plates on its end faces and is mountable on the stand pipe. A cup-shaped screw housing of the filter can be screwed to a free end of the stand pipe, and supports a seal on a free edge thereof, via which the screw housing is sealable against a connection flange sealing surface when mounted. The filter has a first arrangement on an end face area to center the end face area to the flange. The filter insert has a second arrangement on the end face area outer periphery for centering the screw housing free edge relative to the connection flange sealing surface, wherein the second arrangement interacts in a centering manner with the screw housing free edge when installed.

A filter device has a filter housing (14) with a housing pot (12), which accommodates a replaceable filter element (16) and is closed by a removable lid part (32). The element material (20) of the filter element (16) separates an unfiltrate chamber (22) from a filtrate chamber (18, 43). A measurement sensing device (108) senses pressure values from at least one of the chambers (18, 22, 43), is disposed on a lid inner side (45) of the lid part (32), is at least partially guided in the lid part, and projects into the filter housing (14). At least parts of a measurement value evaluator (78) are connected to the measurement sensing device (108) and are disposed on the opposite lid outer side (42) facing the environment.

A filter system including a designated filter cartridge including a geometric projection therein and a filter cartridge housing. The filter cartridge housing including a valve that controls fluid flow out of the filter system, a filter cartridge housing, and a filter cartridge housing cover. The valve may include an opening keyed to the geometric projection such that the geometric projection engages the opening and actuates the valve, and the valve may be configured to attach to the filter cartridge housing cover by a snap fit connection.

A filter system including a designated filter cartridge including a geometric projection therein and a filter cartridge housing. The filter cartridge housing including a valve that controls fluid flow out of the filter system, a filter cartridge housing, and a filter cartridge housing cover. The valve may include an opening keyed to the geometric projection such that the geometric projection engages the opening and actuates the valve, and the valve may be configured to attach to the filter cartridge housing cover by a snap fit connection.