Exhaust apparatus of outboard motor

摘要

An outboard motor includes an engine holder, an engine disposed above the engine holder and the engine includes a cylinder block provided with a plurality of cylinders, a cylinder head disposed behind the cylinder block and a crankcase, a cam chain case through which said engine is mounted on the engine holder, and an exhaust apparatus operatively connected to the cylinder head. The exhaust apparatus includes an exhaust passage formed to the cam chain case, an exhaust manifold connected to the cylinder head, a water jacket formed to the exhaust manifold and another water jacket formed to the exhaust passage. The exhaust passage is formed at a portion near a central portion of the engine having most wide width in association with a lower end portion of the exhaust manifold.