In one embodiment, a valve assembly may include a housing, a cage inside the housing, a first spring arranged inside the housing and outside of the cage, and a poppet inside the cage. The cage may have a first orifice as defined by a bottom edge of the cage, which sits on a first supporting structure of the housing. The first spring may have a top end pressing against a top edge of the cage and a bottom end sitting on a second supporting structure. The poppet may have a top end coupled to an armature movable longitudinally, and a bottom end coupled to a hat-shaped valve. The hat-shaped valve may be coupled to a second spring under the hat-shaped valve, which is configured to push the hat-shaped valve upwards and cause the hat-shaped valve to be releasably engaged with a seal structure of the poppet.

The present invention provides an integrated auxiliary fuel oil tank for a vehicle, which structurally includes a fuel oil tank body, wherein a gear pump assembly and a coarse filter are mounted on the inner side of the fuel oil tank body, and a fuel oil suction passage passing through the coarse filter and a fuel oil return pipeline are arranged between the fuel oil tank body and an engine fuel oil system. The gear pump assembly is provided with a first passage during forward rotation, and a fuel oil filling passage is arranged between the main fuel oil tank of the vehicle and the fuel oil tank body. The gear pump assembly is further provided with a second passage during reverse rotation, and an active fuel oil supply passage is further arranged between the fuel oil tank body and the engine fuel oil system.

A fuel tank comprising a tank and a venting system is disclosed. The tank comprises a housing defining a tank cavity and a port defined in the housing in communication with the tank cavity. The venting system comprises a base attached to the housing, wherein the base defines a base cavity in fluid communication with the tank cavity through the port and a relief housing movably connected to the base, wherein the relief housing is movable between a first position and a second position, wherein a sealed interface is defined between the base and the relief housing when the relief housing is in its first position, wherein the relief housing comprises an open vent aperture in fluid communication with the base cavity, and wherein the sealed interface is unsealed when the relief housing is in its second position to expose a relief vent aperture in the base.