Outboard Marine Corporation

Tim Bowhall

Todd D Craft

Dave Mate

An engine having an engine block defining at least two cylinders having respective cylinder heads. Pistons are reciprocal within respective ones of the cylinders. The cylinders have respective fuel inlet ports and exhaust ports and two of said cylinders have an idle relief port disposed between their respective exhaust port and head ends. The idle relief ports of the cylinders are interconnected by a passageway for providing communication between the idle relief ports of said at least two cylinders. This has been found to provide reduced pull start resistance, reduced engine vibration during idle, and significantly reduced horsepower loss over a wide operating range which horsepower loss is normally associated with idle prior art relief structures which vent directly from idle relief ports to atmosphere.

Growing community of inventors

Kenosha, WI, United States of America

Tim Bowhall