| 主权项 |
1. An exhaust apparatus of an outboard motor equipped with a four-stroke engine which includes a cylinder block provided therein with a cylinder so as to extend in a horizontal direction, a cylinder head fixed to the cylinder block so as to cover the cylinder and form a combustion chamber in conjunction with the cylinder, a crankcase adapted to house a crankshaft so as to extend in a vertical direction, and an exhaust apparatus, in which the cylinder head is formed with an intake port and an exhaust port communicated with the combustion chamber, wherein
the exhaust apparatus includes a plurality of cylinder units each equipped with the cylinder, the combustion chamber, the intake port, and the exhaust port which are arranged side by side in the vertical direction in the cylinder block and the cylinder head, an exhaust manifold is formed on one side of the cylinder block in a width direction of an outboard motor so as to be communicated with the exhaust ports of the plurality of cylinder units and extending in parallel to the crankshaft, an exhaust pipe having a cylindrical shape and connected to an exhaust passage of an engine holder is disposed in an exhaust passage of the exhaust manifold in a manner being erected upright in parallel to the crankshaft, and the exhaust pipe has an upper end opened in an upper portion of the exhaust passage and a lower end supporting the cylinder block, and the exhaust manifold and the exhaust pipe are provided with a gap therebetween in a plan view acting as an exhaust collection space adapted to collect exhaust gas from the exhaust manifold. |
