| 摘要 |
The invention relates to a cooling structure for an internal combustion engine. In the internal combustion engine which has a cylinder head (4) that defines an exhaust merging portion (17) inside, a region which surrounds an exhaust gas outlet (18), which is defined in a longitudinal center on an exhaust side of the cylinder head, is appropriately cooled without increasing the required amount of cooling water or the size of the cylinder head. The cylinder head is provided therein with a main water jacket (51) covering a combustion chambers from the top, and a lower and an upper exhaust water jacket (53, 54) each covering the exhaust merging part from below and above, with the main water jacket provided with multiple cooling water intakes (50) surrounding respective cylinder bores and being communicated with the lower exhaust water jacket. A vertical passage (55) communicated with the two exhaust water jackets is provided in a part of the other exhaust water jacket, which is offset from a position thereof corresponding to the exhaust gas outlet in a cylinder row direction to one side. |
