| 摘要 |
PURPOSE:To prevent without fail cooling water and combustion gas from leaking, by forming a gas expansion groove in a joining surface between a cylinder block and a cylinder head, and interconnecting this gas expansion groove to a suction passage or an exhaust passage through an interconnecting passage. CONSTITUTION:Each of water jackets 8 and 9 is formed in a cylinder block 1 and a cylinder head 2. Plural almost annular gas expansion grooves 15a and 15b are formed in the outer circumferential side of at least one side bore in joining surfaces between the cylinder block 1 and the cylinder head 2. The combustion gas inside the second gas expansion groove 15b is degassed to an exhaust passage 19 by a vent hole 16. This vent hole 16 may be opened to a suction passage 20. Thus, leaks of cooling water and combustion gas from these joining surfaces between the cylinder block and cylinder head are surely kept back and, what is more, engine performance is improvable. |
