Patent 7685982 was granted and assigned to Honda on March, 2010 by the United States Patent and Trademark Office.
An outboard engine unit includes a single lubricating oil supply tube for supplying lubricating oil to a valve-operating chain. The valve-operating chain is suspended across a drive sprocket provided to a crankshaft and a driven sprocket provided to a camshaft. A supply tube is connected to a main gallery that is linked to a main oil channel positioned in an area adjacent to the crankshaft.