Patent Number: 6,250,976

Title: Exhaust emission control for watercraft

Abstract: A watercraft includes a monitoring and control system to sense the operational state of a catalytic device and a cooling system used with an exhaust system of the watercraft. The monitoring and control system receives temperature reading from an exhaust system temperature sensor. The sensor desirably is located in a portion of the exhaust system which the cooling system cools. The monitor and control system activates a first level warning indicators if the sensed temperature of the exhaust system exceeds a preselected first warning temperature. And if the sensed temperature exceeds a presented second warning temperature, the monitoring and control system reduces engine speed and eventually stops the engine. The monitor and control system also communicate with an exhaust gas temperature sensor which is located in the vicinity of a catalytic device of the exhaust system. If the sensed temperature is within a desired temperature range, the control system activates a system-ready indicator. If, however, the sensed temperature exceeds the desired temperature range, the control system activates warning indicators.

Inventors: Ozawa; Shigeyuki (Iwata, JP)

Assignee: Yamaha Hatsudoki Kabushiki Kaisha

International Classification: F01N 11/00 (20060101); F01N 3/28 (20060101); F01N 7/00 (20060101); F01P 11/16 (20060101); F02D 41/14 (20060101); F01P 11/14 (20060101); F02B 61/00 (20060101); F02B 61/04 (20060101); B63B 35/73 (20060101); B63H 021/22 ()

Expiration Date: 06/26/2018