Abstract: A marine propulsion system (2) is provided with an exhaust elbow (10) having an intake exhaust passage (22) extending upwardly from the engine (4) and communicating through a bend (24) with a discharge exhaust passage (26), and a water jacket (27) having pockets around the exhaust passages for cooling the latter. A central channel (44) extends longitudinally along the exterior of the exhaust passages to guide water therealong to the end (42) of the discharge exhaust passage to mix with exhaust thereat. The central channel has a pair of sidewalls (50 and 52) extending longitudinally and laterally tapered away from each other (54 and 56) at the outer end of the discharge exhaust passage to create an outward draw from the central channel to minimize break-up of longitudinally outward water flow and maintain the end tip of the discharge exhaust passage dry and prevent water ingestion and creeping back into the discharge exhaust passage due to pulsations of the engine.