Abstract: Of a sensing part and a mounting part of an oil level sensor mounted to a sensor mounting opening at a bottom portion of an oil pan of an engine, an undersurface of the mounting part exposed to the outside of the oil pan is located above the lowest part of the oil pan by a distance, and the mounting part is disposed in a recessed part formed on an undersurface of the oil pan and is covered with a cover plate. Therefore, the weight of the engine does not directly act on the mounting part of the oil level sensor when the engine is directly placed on a floor surface. Further, even in a state in which the engine is mounted on a vehicle body, the mounting part of the oil level sensor can be also effectively protected at the time of colliding with a flying stone, riding on a curbstone, jacking up or the like.

Abstract: Of a sensing part and a mounting part of an oil level sensor mounted to a sensor mounting opening at a bottom portion of an oil pan of an engine, an undersurface of the mounting part exposed to the outside of the oil pan is located above the lowest part of the oil pan by a distance, and the mounting part is disposed in a recessed part formed on an undersurface of the oil pan and is covered with a cover plate. Therefore, the weight of the engine does not directly act on the mounting part of the oil level sensor when the engine is directly placed on a floor surface. Further, even in a state in which the engine is mounted on a vehicle body, the mounting part of the oil level sensor can be also effectively protected at the time of colliding with a flying stone, riding on a curbstone, jacking up or the like.

Abstract: In an intake port structure in an internal combustion engine, an edge portion is formed on a lower surface of an intake port at a location immediately upstream of an intake bore 7. The angle .theta. formed by the center line L of the intake port with respect to a deck surface is set smaller than the angle .theta..sub. formed by an exhaust valve seat provided in a pent roof of a combustion chamber with respect to the deck surface. Further, if the height of an apex of the pent roof of the combustion chamber is represented by H.sub.0, and an intersection between an extension of the center line L of the intake port 5 and a straight vertical line L.sub.0 passing through the apex of the pent roof of the combustion chamber to intersect the deck surface at a right angle is represented by P, the height H of the intersection P is set so that a relation, H.sub.0 >H>2H.sub.0 /3 is satisfied.