They also eliminate the laceration dangers of an open propeller. Although less efficient than an open propeller, they are particularly useful in applications where the ability to operate in very shallow water is important. Pump-jet propulsion is available as an option on most outboard motors. As these engines do not use permanent magnets, they require less maintenance and develop more torque at lower RPM. The advantage of the induction or asynchronous motor is the power transfer to the rotor by means of electromagnetic induction. With this setup, a motor can produce 10 kW output or more and is able to replace a petrol engine of 15 HP or more. Recently developed outboard motors are powered with an alternating current (AC) or DC electric motor in the power head like a conventional petrol engine. Most electric outboard motors have 0.5 to 4 kW direct current (DC) electric motors, operated at 12 to 60 volts DC. These are not to be confused with trolling motors, which are not designed as a primary source of power. In addition many small motor manufacturers have begun offering variants with power trim/tilt and electric starting functions so that they may be completely controlled remotelyĮlectric outboard motors are self-contained propulsory units for boats, first invented in 1973 by Morton Ray of Ray Electric Outboards. In this application, the motor is frequently installed on the transom alongside and connected to the primary outboard to enable helm steering. for trolling aboard larger craft, as small outboards are typically more efficient at trolling speeds.to provide auxiliary power for sailboats.to power small craft such as jon boats, dinghies, canoes, etc.The smallest of these weigh as little as 12 kilograms (26 lb), have integral fuel tanks, and provide sufficient power to move a small dinghy at around 8 knots (15 km/h 9.2 mph) These motors typically use a manual start system, with throttle and gearshift controls mounted on the body of the motor, and a tiller for steering. They are affixed to the boat via clamps and thus easily moved from boat to boat. Small outboard motors, up to 15 horsepower or so, are easily portable. 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 627 hp (468 kW)., with sufficient power to be used on boats of 37 feet (11 m) or longer. Generally motors of 100 hp plus are linked to controls at the helm. Large outboards are affixed to the transom using clamps and are either tiller steered or controlled from the helm. General use A motorboat with an outboard motor attached to it Large outboards If the electric motor required to move the pistons which raise or lower the engine is malfunctioning, every outboard motor is equipped with a manual piston release which will allow the operator to drop the motor down to its lowest setting. This helps when traveling through shallow waters where there may be debris that could potentially damage the motor as well as the propeller. In order to eliminate the chances of hitting bottom with an outboard motor, the motor can be tilted up to an elevated position either electronically or manually. A Mercury Marine 50 hp outboard engine, circa 1980 to 1983 1979 Evinrude 70 hp outboard, cowling and air silencer removed, exposing its shift/ throttle/ spark advance linkages, flywheel, and three carburetors Unlike inboard motors, outboard motors can be easily removed for storage or repairs.īolinder's two-cylinder Trim outboard engine. The skeg also acts as a rudder when the engine is not running. 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. They are the most common motorised method of propelling small watercraft. JSTOR ( April 2012) ( Learn how and when to remove this template message)Īn outboard motor is a propulsion system for boats, consisting of a self-contained unit that includes engine, gearbox and propeller or jet drive, designed to be affixed to the outside of the transom.Unsourced material may be challenged and removed. Please help improve this article by adding citations to reliable sources. This article needs additional citations for verification.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |