| 摘要 |
PURPOSE:To enhance the intake air preheating effect on the starting in the cold condition, by improving the cooling water stream construction, in a system where a cylinder bore axial line is inclined to a horizontal surface, and an intake air preheating passage is interposed in an intake air manifold. CONSTITUTION:In an internal combustion engine with the axial line 2 of a cylinder bore inclined at a suitable angle theta to a horizontal line 3, an intake manifold 7 is connected to the longitudinal side surface of a cylinder head 5, and an intake air preheating passage 9 communicating to the cooling water chamber 8 of a cylinder head 5 at the position of each cylinder is formed integrally with the bottom surface of the intake manifold 7. And also, a cooling water outlet 10 is provided toward the cooling water chamber 8 so as to be connected to a radiator through a discharge passage 12 provided with a cooling water filler 13 in the middle of the way. A thermocontrol valve 19 for closing the passage 16 and opening a by-pass passage 17 at the time of the low temperature is interposed, in a cooling water return passage 16 leading to the cooling water chamber 8, so that the return passage 16 and an air vent passage 14 are connected to each other through a second by-pass passage 20. |
