The Basics


An outboard motor is a propulsion system for boats, consisting of a self-contained unit that includes engine, gearbox and propeller jet drive, designed to be affixed to the outside of the transom.  They are the most common motorized method of propelling small watercraft.  As well as providing propulsion, outboards provide steering control, as they are designed to pivot over their mountings and thus control the direction of thrust.  The skeg also acts as a rudder when the engine is not running. Unlike inboard motors,, outboard motors can be easily removed for storage or repairs.


Large outboards are usually bolted to the transom (or to a bracket bolted to the transom), and are linked to controls at the helm.  These range from 2-, 3- and 4-cylinder models generating 15 to 135 horsepower suitable for hulls up to 17 feet (5.2 m) in length, to powerful V6 and V8 cylinder blocks rated up to 557 hp. with sufficient power to be used on boats of 37 feet (11 m) or longer.