Patent ID: 8813715

Claim:
A vertical engine including: a cylinder barrel having formed therein a cylinder for reciprocatively guiding a piston, and a crankcase rotatably supporting a crankshaft having an axis line oriented in a substantially vertical direction; a cylinder head closing a cylinder-side opening of the cylinder barrel from a lateral side thereof; an oil pan provided in a lower region of the cylinder barrel; an intake valve and an exhaust valve provided on the cylinder head; and a cam gear shaft provided in the crankcase and having cams for driving the intake valve and the exhaust valve, respectively, wherein the vertical engine comprises: an oil pump provided in the cylinder barrel adjacent to a lower surface of the cylinder barrel and connected to a lower end portion of the cam gear shaft to be driven by the cam gear shaft; a first lubricating oil passageway for supplying lubricating oil, sent out from the oil pump, to a lower bearing of the crankshaft; a second lubricating oil passageway extending through an interior of the crankshaft from the lower bearing to an upper bearing of the crankshaft; a third lubricating oil passageway provided in the cylinder barrel adjacent to an upper surface of the cylinder barrel and extending from the crankcase to immediately below stem end portions of the air intake valve and the exhaust valve so that lubricating oil leaked from the second lubricating oil passageway flows therethrough; and a fourth lubricating oil passageway for returning lubricating oil, dripped down from the third lubricating oil passageway to the stem end portions of the air intake valve and the exhaust valve, to the oil pump, wherein the first lubricating oil passageway has a crank-side shaft-end supply opening for supplying lubricating oil to a lower end face of the crankshaft to press the crankshaft upward.