Exhaust system for watercraft

摘要

A number of exhaust systems for watercraft propelled by a propulsion unit contained within a tunnel formed in the underside of the hull. This tunnel has an opening through the side of the hull and exhaust gases are delivered to the tunnel from the engine through an exhaust system having an exhaust opening communicating with the tunnel. Various flow controlling arrangements are provided for controlling the flow through one or all of the openings so as to assist in exhaust silencing without significantly increasing back pressure.