An internal combustion engine includes a cylinder head, a crankshaft, intake and exhaust camshafts, first and second chain covers, a chain, and a fastening bolt. The first chain cover having a cutout includes a first flange positioned at a specific edge portion of the cutout, which is positioned between the crankshaft and the camshafts, and a first boss through which a shaft portion of the fastening bolt is passed. The cylinder head includes a second flange, and a second boss into which the shaft portion is inserted, and which is disposed coaxially with the first boss. The liquid gasket is held between the second flange and the first flange. A groove is provided in at least one of a position between the first flange and the first boss of the first chain cover and a position between the second flange and the second boss of the cylinder head.

The present invention provides an engine cover that can be manufactured easily and at a lower cost and has an attachment member that is high in quality and may not easily fall off. The engine cover has a cover body made of urethane foam, a skin layer disposed on a surface of the cover body, and an attachment member made of an elastic body and integrally molded with the cover body. The attachment member has a recess into which an attachment pin provided to project from an engine member is fitted, and a sealing portion that is provided to project at least one of the opening end surface of the recess and the side surface of the opening end part of the recess and that suppresses entry of a foamed urethane resin material that forms the cover body into the recess during integral molding.

A locking clip is disclosed for fixing an elongated object externally with respect to an internal combustion engine. The locking clip includes first and second plates connected by a looping portion. The first plate is inclined with respect to the second plate by an angle of inclination. The first and second plates are provided with through holes. Protuberances extend from the first and second plates into the through holes and are configured to engage with a threaded portion of a threaded fastener extending from the internal combustion engine.

An engine-driven working machine capable of suppressing vibration, and further securing output power of an engine is provided. An engine-driven working machine 10 is a generator in which an outer case 12 is formed to be substantially rectangular in plan view that extends in a longitudinal direction, and an engine 15 is housed in an inside 13 of the outer case 12. In the generator 10, a crankshaft 41 is disposed to intersect the longitudinal direction of the outer case 12. Further, an intake port 44 and an exhaust port 45 are disposed in the longitudinal direction of the outer case 12. Furthermore, a carburetor 61 is disposed at a side of the intake port 44, and a muffler 67 is disposed at a side of the exhaust port 45.

An engine includes an output shaft, a cylinder block, a cylinder head, a cap portion, and head bolts. The cylinder block, the cylinder head, and the cap portion are fastened together with the head bolts. The cylinder block includes a cylinder portion and a plurality of output shaft supporting portions. When an outer wall face of at least one of the plurality of output shaft supporting portions is viewed along an output shaft axial direction, the outer wall face includes a first rib diagonally extending from a supporting portion of the output shaft toward one of two head bolt holes.

An internal combustion engine and related components and methods of manufacturing and implementing an internal combustion engine and related components. The internal combustion engine includes a base, a cylinder block mounted onto the base, a cylinder head mounted onto the block, and a structural overhead member mounted onto the cylinder head, such that the cylinder head is positioned between the cylinder block and the structural overhead member. At least one through-bolt positioned in a through-bolt opening, the through-bolt opening extending from the base to the structural overhead member through the cylinder block and the cylinder head to couple the base, the cylinder block, the cylinder head and the structural overhead member together.

A lubricant conducting member includes a lubricant conducting housing arranged between a crankcase and a lubricant collecting trough. The lubricant housing is surrounded by a bordering edge, and a projection of the bordering edge delimits an area in a plane parallel to a standing plane of the motor vehicle. A cumulative area of all of the lubricant passage openings is smaller than ⅓ of the area. In a perpendicular view, from the standing plane of the motor vehicle onto the lubricant conducting housing, in particular the view from below at least one lubricant passage opening, all lubricant passage openings are completely covered by the lubricant recirculation system.

A lubricant conducting member includes a lubricant conducting housing arranged between a crankcase and a lubricant collecting trough. The lubricant housing is surrounded by a bordering edge, and a projection of the bordering edge delimits an area in a plane parallel to a standing plane of the motor vehicle. A cumulative area of all of the lubricant passage openings is smaller than ⅓ of the area. In a perpendicular view, from the standing plane of the motor vehicle onto the lubricant conducting housing, in particular the view from below at least one lubricant passage opening, all lubricant passage openings are completely covered by the lubricant recirculation system.

To provide a surface structure of an aluminum-based member which can further improve heat insulating properties and heat shielding properties of the aluminum-based member. In an aluminum-based member 1 containing at least a silicon composition, a porous oxide film 2 is provided on a surface of the aluminum-based member 1, and the oxide film 2 is constituted to have at least a pore 2a extending from the surface toward an inside in a thickness direction of the oxide film 2 and a void 3a present inside the silicon composition 3 extending in a direction substantially orthogonal to the thickness direction of the oxide film 2.

A two-stroke internal combustion engine has an engine block having a cylinder block and a cylinder head. The cylinder block defines a cylinder, an exhaust passage, and an exhaust valve passage. The engine also has a piston, an exhaust valve actuator operatively connected to at least one of the cylinder block and the cylinder head, and a reciprocating exhaust valve disposed at least in part in the exhaust valve passage. The exhaust valve has a shaft operatively connected to a valve actuator, and a blade connected to the shaft. A channel is defined along a face of the blade. The channel and a wall of the exhaust valve passage together define at least in part a valve passage. The valve passage permits flow of exhaust gas along the face of the blade. A width of the valve passage is at least a third of a width of the blade.