How a car engine works?

 

A single piston, the powerhouse of the engine, and work our way outwards. The 4-stroke cycle. When a piston travels to the end of its range whether up or down that’s a stroke. Car engines use a 4-stroke cycle, and it goes like this: First, intake. The piston descends, sucking on air fuel mixture into the cylinder through the intake port with both intake valves open. Next compression. With all valves closed the piston comes back up, compressing the fuel and air mixture for more powerful combustion. Then, the power stroke. An electrical spark ignites the compressed fuel and air mixture, and the resulting combustion forces the piston to the bottom of the cylinder again. A connecting rod transfers this power to the crankshaft. Finally, exhaust. A piston comes back up pushing the spent mixture out through open exhaust valves and the exhaust port. Connecting multiple pistons for smooth power delivery, pistons take turns firing. The firing order for this engine is 1-3-4-2. Camshafts with especially shaped cams push spinning-loaded valves open in turn. Cam gear and a timing belt or chain links everything to the crankshaft, and it all spins together. The crankshaft translates piston power out of the engine. It has counterweights to balance against the pistons for perfectly smooth revolutions. This is what rpm means. We’re counting the number of full crankshaft revolutions per minute. The engine block holds the crankshaft and cylinders, and the cylinder head holds valves, parts etc. A geared flywheel sits at one side of the crankshaft for connection to a transmission. Its also where the starter connects to the system. This engine has four cylinders arranged in a single row. But there are many possible configurations, like six cylinders with three on each side, angled in a V shape or eight. Despite different design goals, the basic engine parts are all there. Now let’s look at the other systems that support this combustion process. Air intake. Air comes in through an air filter and then into the intake manifold where it mixes with fuel before being sucked into individual cylinders through intake parts. Fuel. The fuel pump carries gas from the tank, through a fuel filter, to the engine where fuel injectors emit a precisely timed sprat of gas into the intake part. Cooling. Engines get very hot during operation and requires a cooling system. Coolant channels around cylinders and through the cylinder head carry a special liquid called anti-freeze to keep temperature within safe operating range. It is called anti-freeze because it won’t freeze in icy weather. After cooling hot engine parts, coolants circulate through the radiator. The radiator has a network of small tubes and fins. Coolant passes through these channels while air pulled in by the radiator fan flows by the tubes, cooling the hot liquid for recirculation. A water pump keeps the coolant system flowing and properly pressurized. The thermostat regulates coolant temperature by either routing coolant back through the engine or to the radiator for further cooling. Electrical. The spark plug delivers the electrical spark that ignites the fuel air mixture for combustion. The metal core is insulated from the out-metal casing with porcelain. The spark jumps between these conductive surfaces. The coil pack delivers electrical current to the spark plugs as directed by the Cem (engine control module). The ECM is a computer that directs many cores engine functions like spark timings, valve timing, air to fuel ratio etc.