Outboard motor unit with underwater exhaust - has catalytic converter in pipe between boat engine and exhaust outlet

摘要

The outboard motor (30) for a boat swivels about a vertical steering axis (34) having an exhaust gas outlet (42) for bringing out the exhaust gases under water. An exhaust gas connection channel is provided between the motor head (58) and the exhaust gas outlet which has upstream and downstream sections joined by a section with a wall (102) below which is attached a catalytic converter (174) for the exhaust gases. ADVANTAGE - Exhaust system in which the catalytic converter is placed below the maximum normal water level (170) at a considerable distance from the motor head.