Abstract: A fuel supply device has a main line, a fuel pump, a first return line, a second return line, a valve mechanism, a first pressure regulator, and a second pressure regulator. The fuel pump pressurizes the fuel in the fuel tank and supplies the fuel to a fuel distribution pipe via the main line. The first return line returns the fuel from the fuel distribution pipe to the fuel tank. The second return line is branched from the main line and returns the fuel from the main line to the fuel tank. The valve mechanism selectively connects and disconnects the second return line with respect to the main line. The first pressure regulator is arranged in the first return line. The second pressure regulator is provided in the second return line and adjusts fuel pressure to a lower level than the first pressure regulator does.

Abstract: A fuel supply device has a main line, a fuel pump, a first return line, a second return line, a valve mechanism, a first pressure regulator, and a second pressure regulator. The fuel pump is arranged in a fuel tank or in the vicinity of the fuel tank, and pressurizes the fuel in the fuel tank and supplies the furl to a fuel distribution pipe via the main line. The first return line returns the fuel from the fuel distribution pipe to the fuel tank. The second return line is branched from the main line in the vicinity of the fuel pump and returns the fuel from the main line to the fuel tank. The valve mechanism selectively connects and disconnects the second return line with respect to the main line. The first pressure regulator is arranged in the first return line. The second pressure regulator is provided in the second return line and adjusts fuel pressure to a lower level than the first pressure regulator does.

Abstract: This invention relates to an internal combustion engine including an oil seal ring between a cylinder block and a crank shaft, a crank shaft cap and a conduit. The cylinder block includes a plurality of cylinders, a crank shaft support portion and an oil seal retainer. The crank shaft support portion is located under the plurality of cylinders and the oil seal retainer projects outwardly from the cylinder block. A crank case is defined within the cylinder block. The crank shaft cap is secured to the crank shaft support portion and an opening is defined therebetween. The crank shaft includes a main journal and a flange portion. The main journal is inserted into the opening defined between the crank shaft support portion and the crank shaft cap. The crank shaft is rotatably mounted on both the cylinder block and the crank shaft cap.