A fuel passage structure of a fuel supply device is configured to supply fuel from a fuel tank to an internal combustion engine. The fuel passage structure includes a passage-forming member that forms a fuel passage and a check valve. The fuel passage includes a vertical passage extending in a vertical direction and a lateral passage extending in a horizontal direction. The check valve is disposed at an intersection of the vertical passage and the lateral passage. The check valve includes a valve body configured to close under its own weight. The valve body is movably arranged within the vertical passage in the vertical direction. The check valve is provided with a restriction member which restricts movement of the valve body into the lateral passage, while at the same time the restriction member does not disturb the forward flow of the pressurized fuel.

Methods and systems are provided for injecting gaseous fuel during an engine start. In one example, a method comprises generating gaseous fuel via a fuel gasification device and injecting the gaseous fuel via a fuel injector. The fuel injector is configured to inject adjacent to an ignition device.

Methods and systems are provided for injecting gaseous fuel during an engine start. In one example, a method comprises generating gaseous fuel via a fuel gasification device and injecting the gaseous fuel via a fuel injector. The fuel injector is configured to inject adjacent to an ignition device.

A fluid pump includes a housing; an inlet passage; an outlet conduit; a pumping element within the housing; and a check valve assembly. The check valve assembly includes a valve stem within the outlet conduit such that a flow path is created radially between the outlet conduit and the valve stem, the valve stem moving along a check valve assembly axis between a closed position and an open position. The flow path includes a first restriction which increases velocity of fluid passing through the flow path; a first expansion, downstream of the first restriction, which decreases velocity of fluid passing through the flow path; a second restriction, downstream of the first expansion, which increases velocity of fluid passing through the flow path; and a second expansion, downstream of the second restriction, which decreases velocity of fluid passing through the flow path.

In at least some implementations, a carburetor includes a body, a fuel pump diaphragm and a pressure pulse passage. The fuel pump diaphragm is carried by the body and defines in part a fuel chamber on one side of the fuel pump diaphragm and a pressure pulse chamber on the other side of the fuel pump diaphragm. The pressure pulse passage communicates the pressure pulse chamber with a pressure pulse source to provide pressure pulses in the pressure pulse chamber to actuate the fuel pump diaphragm. The pressure pulse passage includes an inlet communicating with a passage in which pressure pulses are present and the inlet is spaced from a surface defining the passage in which pressure pulses are present.

Responsiveness is improved in valve opening and valve closing of an electromagnetically driven intake valve unit in which a valve is provided on a pressurizing chamber side of a valve seat. The valve includes an annular abutting surface that abuts the valve seat to shut off a fuel intake passage and a bottomed cylindrical part provided at an inner peripheral part of the annular abutting surface. The bottomed cylindrical part is inserted into a fuel introduction hole formed in the valve housing inside the valve seat, and the outer surface of an end part of the bottomed cylindrical part is exposed to fuel in a low pressure fuel chamber provided upstream of the fuel introduction hole.

Methods and systems are provided for a gear driven diesel fuel injection pump of an engine. In one example, a front end of an engine includes an idler gear in meshing engagement with a first end of a crankshaft and a fuel pump drive gear in meshing engagement with the idler gear. The front end of the engine may further include a fuel pump, where an input shaft of the fuel pump is directly coupled to the fuel pump drive gear.

A starting system for an internal combustion engine that includes: a pump device in communication with a purging and priming circuit of a carburetor; a driven member coupled to the pump device; and a drive member rotatably carried by a recoil starter pulley of an engine. The drive member may positively drive the driven member in two directions, and the driving of the driven member may actuate the pump device.

A starting system for an internal combustion engine that includes: a pump device in communication with a purging and priming circuit of a carburetor; a driven member coupled to the pump device; and a drive member rotatably carried by a recoil starter pulley of an engine. The drive member may positively drive the driven member in two directions, and the driving of the driven member may actuate the pump device.