How the Modern Car Engine Works

The modern car engine is a complex piece of machinery, but it can be boiled down to a few basic principles. In this article, we’ll take a look at how car engines work, from the basics of combustion to the latest advances in engine technology.

The Four-Stroke Cycle

All modern car engines operate on the four-stroke cycle. This cycle consists of four main steps:

1. Intake stroke: During the intake stroke, the piston moves down the cylinder, drawing air and fuel into the cylinder through the intake valve.
2. Compression stroke: Once the piston reaches the bottom of the cylinder, the intake valve closes and the piston moves back up the cylinder, compressing the air and fuel mixture.
3. Power stroke: When the piston reaches the top of the cylinder, the spark plug ignites the air and fuel mixture, creating an explosion that drives the piston back down the cylinder.
4. Exhaust stroke: Once the piston reaches the bottom of the cylinder again, the exhaust valve opens and the piston moves back up the cylinder, pushing the exhaust gases out of the cylinder through the exhaust valve.

The four-stroke cycle is repeated over and over again, providing the power to drive the car.

The Valve Train

The valve train is a system of valves and camshafts that controls the opening and closing of the intake and exhaust valves. The camshafts are driven by the crankshaft, and they open and close the valves at the appropriate times during the four-stroke cycle.

The Fuel System

The fuel system delivers fuel from the fuel tank to the engine. The fuel system consists of a fuel pump, fuel filter, and fuel injectors. The fuel pump draws fuel from the fuel tank and sends it to the fuel filter, which removes any impurities from the fuel. The fuel injectors then spray the fuel into the cylinders at the appropriate times during the four-stroke cycle.

The Ignition System

The ignition system provides the spark that ignites the air and fuel mixture in the cylinders. The ignition system consists of a battery, ignition coil, spark plugs, and distributor. The battery provides the electrical power to the ignition coil, which generates a high-voltage spark. The distributor then sends the spark to the spark plugs, which ignite the air and fuel mixture.

The Lubrication System

The lubrication system circulates oil throughout the engine to reduce friction and wear. The lubrication system consists of an oil pump, oil filter, and oil passages. The oil pump draws oil from the oil pan and sends it to the oil filter, which removes any impurities from the oil. The oil then flows through the oil passages to the various parts of the engine, lubricating them and reducing friction.

The Cooling System

The cooling system prevents the engine from overheating. The cooling system consists of a radiator, water pump, and thermostat. The water pump circulates coolant through the engine, absorbing heat from the engine. The coolant then flows through the radiator, where it is cooled by the air flowing through the radiator. The thermostat controls the flow of coolant through the radiator, ensuring that the engine does not overheat.

Engine Management Systems

Modern car engines are controlled by engine management systems (EMSs). EMSs are computer systems that monitor the engine’s performance and adjust the engine’s operation to ensure that it runs efficiently and smoothly. EMSs typically control the fuel injection, ignition timing, and valve timing.

Conclusion

The modern car engine is a complex piece of machinery, but it is based on a few simple principles. By understanding how car engines work, you can better appreciate the engineering that goes into them and the importance of regular maintenance.