Stern drives and water lift exhaust systems for stern drives

摘要

A stern drive is for propelling a marine vessel in water. The stern drive is configured to power a propulsor located below the surface of the water. The stern drive comprises an internal combustion engine that powers a driveshaft that axially extends through a transom of the marine vessel; an exhaust manifold that conveys exhaust gas from the internal combustion engine; and an elongated exhaust conduit that redirects the exhaust gas from the exhaust manifold transversely with respect to the driveshaft. The elongated exhaust conduit conveys the exhaust gas to an upstream exhaust outlet that discharges the exhaust gas through the transom below the surface of the water and then to a downstream exhaust outlet that is spaced apart from and is located vertically higher than the upstream exhaust outlet. The elongated exhaust conduit functions as a water lift muffler during operation of the stern drive.