| 摘要 |
PROBLEM TO BE SOLVED: To enhance cooling performance in a surrounding of a plug hole by allowing a cooling oil that is supplied to a plug surrounding cooling oil path to be hardly warmed, in an oil cooled engine which includes a cooling oil circulation path for circulating a cooling oil in an engine body, and in which the plug surrounding cooling oil path constituting the cooling oil circulation path is arranged at a cylinder head to surround the plug hole.SOLUTION: The plug hole 67 is disposed on one side of a plane surface PL containing a straight line connecting the centers of openings of an exhaust port 25 and an intake port 24 to a combustion chamber 22 on a projection figure to a plane surface which intersects with the axis C of a cylinder bore, and a cooling oil supply path 61 that constitutes a part of the cooling oil circulation path 50 and is connected to the upstream end of the plug surrounding cooling oil path 68 is provided on a cylinder head 15 to be disposed at one side of the plane surface PL and closer to the intake port 24 than the exhaust port 25. |
