| 摘要 |
PURPOSE:To increase the cooling water velocity in the cooling water jacket at the portion between the cylinders by providing a dam like object on the upper deck of the cylinderhead cooling water jacket at the said portion extending toward the lower deck and having an air vent hole at its top end. CONSTITUTION:A dam like object 7 extending toward a lower deck 5 and having an air vent hole 9 at approximately same plane as an upper deck 2 is provided on said upper deck which forms a passage for the cylinderhead cooling water at the position corresponding to the portion between each cylinder. The cooling water velocity in the jacket at the portion between each cylinder is increased by the constricting action of the said dam like object whereby eliminating the stagnation of the flow at such portion and improving the cooling effect to prevent the knocking. |
