For other uses, see Engine (disambiguation).
"Motor" redirects here. For other uses, see Motor (disambiguation).
A V6 internal combustion engine from a Mercedes car
An engine or motor is a machine designed to convert one form of energy into mechanical energy.12 Heat engines, including internal combustion engines and external combustion engines (such as steam engines), burn a fuel to create heat, which then creates a force. Electric motors convert electrical energy into mechanical motion; pneumatic motors use compressed air and others?such as clockwork motors in wind-up toys?use elastic energy. In biological systems, molecular motors, like myosins in muscles, use chemical energy to create forces and eventually motion.
the internal combustion engine
The word "engine" derives from Old French engin, from the Latin ingenium?the root of the word ingenious. Pre-industrial weapons of war, such as catapults, trebuchets and battering rams, were called "siege engines", and knowledge of how to construct them was often treated as a military secret. The word "gin", as in "cotton gin", is short for "engine". Most mechanical devices invented during the industrial revolution were described as engines?the steam engine being a notable example. However, the original steam engines, such as those by Thomas Savery, were not mechanical engines but pumps. In this manner, a fire engine in its original form was merely a water pump, with the engine being transported to the fire by horses.
In modern usage, the term engine typically describes devices, like steam engines and internal combustion engines, that burn or otherwise consume fuel to perform mechanical work by exerting a torque or linear force (usually in the form of thrust). Examples of engines which exert a torque include the familiar automobile gasoline and diesel engines, as well as turboshafts. Examples of engines which produce thrust include turbofans and rockets.
When the internal combustion engine was invented, the term "motor" was initially used to distinguish it from the steam engine?which was in wide use at the time, powering locomotives and other vehicles such as steam rollers. "Motor" and "engine" later came to be used interchangeably in casual discourse. However, technically, the two words have different meanings. An engine is a device that burns or otherwise consumes fuel, changing its chemical composition, whereas a motor is a device driven by electricity, air, or hydraulic pressure, which does not change the chemical composition of its energy source.3 However, rocketry uses the term rocket motor, even though they consume fuel.
A heat engine may also serve as a prime mover?a component that transforms the flow or changes in pressure of a fluid into mechanical energy.4 An automobile powered by an internal combustion engine may make use of various motors and pumps, but ultimately all such devices derive their power from the engine. Another way of looking at it is that a motor receives power from an external source, and then converts it into mechanical energy, while an engine creates power from pressure (derived directly from the explosive force of combustion or other chemical reaction, or secondarily from the action of some such force on other substances such as air, water, or steam).5
Devices converting heat energy into motion are commonly referred to simply as engines.6
Repair agricultural vehicles
While working in the country are used for a variety of motor vehicles, from ordinary cars to large combines. In view of the common agricultural vehicles sold cheap motor oils suitable for use in such devices, which must primarily operate smoothly, but also their owners depend on that to serve them as long as possible. Simple repair of agricultural vehicles can be made by their owners, and it is the most practical way to restore the ability of such vehicles to carry out their work at a time when farmers do not wish for too long lose access to their machines. Sometimes, however, they happen in these larger faults that need to be repaired in the service dealing with agricultural machinery.