Patent ID: 7721537

Claim:
An exhaust assembly for a marine genset, the exhaust assembly comprising: an exhaust manifold configured to emit cooling water and exhaust gases from a combustion engine; and a sound-dampening device configured to be coupled between the exhaust manifold and a muffler, the sound-dampening device including a tubular member having an inner diameter and two or more distinct rings located on the inner diameter of the tubular member; each of the rings having surfaces positioned substantially perpendicular to a flow of the cooling water and exhaust gases; each of the rings having a generally circular inner surface exposed directly to an exhaust gas passageway in the tubular member, the inner surface of each of the rings having a substantially uniform inner diameter which defines an opening therethrough, wherein the opening is unobstructed, the rings constricting the passageway which causes mixing of the cooling water with the exhaust gases to reduce noise generated by the combustion engine.