| 摘要 |
PROBLEM TO BE SOLVED: To provide an internal combustion engine capable of accelerating increase in oil temperature of an oil upon warming-up and improving cooling performance for the oil after warming-up.SOLUTION: This engine (internal combustion engine) 1 is configured so that the upper part of a cylinder bore 223 is cooled by cooling water flowing through an upper stage side cooling water passage 221a of a water jacket 221 upon warming-up, and the upper and lower parts of the cylinder bore 223 is cooled by the cooling water flowing through the upper stage side cooling water passage 221a and a lower stage side cooling water passage 221b of the water jacket 221 after warming-up is completed. In oil removing flow paths 222a and 222b, rib portions 23 to 25 (rib portions 26 to 28) are provided extending from a bottom face 22e (22f) of the oil removing flow path 222a (222b) to the height of a partition part 221c of the water jacket 221 or higher. |
