What are the components of an engine?
2 Answers
An engine consists of "two major mechanisms" and "five major systems." The two major mechanisms are the crank-connecting rod mechanism and the valve train mechanism. The five major systems are the fuel supply system, lubrication system, cooling system, ignition system, and starting system. Working principle of an engine: The working chamber of a reciprocating piston internal combustion engine is called the cylinder, and the inner surface of the cylinder is cylindrical. The piston that reciprocates inside the cylinder is hinged to one end of the connecting rod via the piston pin, while the other end of the connecting rod is connected to the crankshaft. The crankshaft is supported by bearings on the engine block and can rotate within the bearings, forming the crank-connecting rod mechanism. When the piston reciprocates inside the cylinder, the connecting rod drives the crankshaft to rotate. Engine working process: Intake stroke: The piston moves downward in the cylinder, the intake valve opens, and air and fuel are drawn in. Compression stroke: The piston moves upward, compressing the mixture of air and fuel, which is then ignited by the spark plug. Power stroke: The compressed air-fuel mixture is ignited and expands, pushing the piston downward, and the connecting rod drives the crankshaft to rotate. Exhaust stroke: The piston is pushed downward by the expanding gases, and after reaching the bottom, the movement of another piston in the cylinder causes the piston to rise, with the exhaust valve opening to expel the exhaust gases.
The core components of an engine include the cylinder block, pistons, crankshaft, and connecting rods, which form the foundation for its operation. The pistons move up and down within the cylinders, driving the crankshaft to rotate and converting combustion force into wheel-driving power. The valve system controls intake and exhaust, with the intake valve introducing the air-fuel mixture and the exhaust valve expelling waste gases. Additionally, the spark plug or fuel injector ignites the fuel, enabling the engine to function. The lubrication system reduces wear and prevents overheating by circulating engine oil, while the cooling system dissipates heat through coolant circulation to maintain stable temperatures. The electronic control unit coordinates all these processes to optimize performance. Despite its complexity, if any component fails—such as a seized piston—the vehicle won't run, so regular inspections of these parts during maintenance are essential.
