| 摘要 |
PROBLEM TO BE SOLVED: To provide a water jacket structure of a cylinder head capable of improving cooling efficiency of an exhaust collection part.SOLUTION: A water jacket structure of a cylinder head 2 comprises: an exhaust collection part 24 for collecting plural exhaust ports 23 inside the cylinder head 2; an exhaust port 24a formed on a side face of the cylinder head 2 and communicated with the exhaust collection part 24; and an exhausting water jacket 70 for cooling the exhaust collection part 24. The exhausting water jacket 70 has: an upper exhausting water jacket 80 arranged on an upper side in a cylinder axial line direction to the exhaust collection part 24; and a lower exhausting water jacket 90 arranged on a lower side in the cylinder axial line direction to the exhaust collection part 24. The exhaust outlet 24a is opened at a position deviated from a center in a cylinder row direction, and the exhaust collection part 24 is enlarged in diameter as it approaches to the exhaust outlet 24a. |
