Exhaust system of outboard motor

Abstract

An outboard motor includes a multi-cylinder engine which includes cylinders longitudinally oriented and vertically paralleled in a cylinder block, a cylinder head arranged at a rearward position of the cylinder blocks, and a crankcase arranged at a forward position of the cylinder block, the cylinder head having an outlet of an exhaust port at one side thereof. An exhaust system for the outboard motor includes an exhaust manifold which communicates the outlet of the exhaust port with an exhaust outlet opening, the exhaust manifold including a first exhaust gas passage extending in a vertical direction for gathering exhaust gas discharged from the outlet of each exhaust port and a second exhaust gas passage extending in a vertical direction adjacently to the first exhaust gas passage, and a catalyst unit is provided on the way of the second exhaust gas passage.

Dependencies are inferred from the claim text.