The piston
The piston is the powerhouse of the car engine. The piston moves up and down. When the piston travels to the end of its range whether up or down, it is called a stroke.
A car engine is equipped with 4 or more pistons. The movement of these pistons is transferred to the wheels of the car which enables it to move.
For car engines, 4 strokes usually completes the engine circle enabling power to be transmitted to the wheels.
The four stroke cycle, how it works.
First stroke; intake.
The piston descends, sucking an air-fuel mixture into the cylinder .
The valves open allowing fuel – mixture into the cylinder
2nd stroke; compression.
With all valves closed the piston comes back up, compressing the fuel and air mixture
3rd stroke ; internal combustion.
An electrical spark from the spark plug ignites the compressed fuel and air mixture inside the cylinder causing an internal combustion. The resulting combustion forces the piston to the bottom of the cylinder again. A connecting rod transfers
this power to the crankshaft which in turn transfers power to the wheels which enable the car to move.
4th stroke; exhaust.
The piston comes back up, pushing the burnt fuel and air mixture out through the
open exhaust valves and the exhaust port.
The pistons and connecting systems
For smooth power delivery, A car uses at least 4 pistons. These pistons take turns to fire the engine.
Camshafts are specially shaped
cams that push spring-loaded valves open in turn.
Cam gears and a timing belt or chain
links everything to the crankshaft. The crankshaft translates piston power from the engine to the wheels.
It has counterweights to balance against the
pistons for perfectly smooth revolutions.
The engine block holds the crankshaft
and cylinders, and the cylinder head holds valves, ports, cams, etc.
A geared flywheel sits at one side of the
crankshaft for connection to a transmission.
The basic car engine has four cylinders
arranged in a single row. But there are many other possible configurations, including six, eight and 12 cylinders.
Systems that support the internal combustion process.
Air intake system
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 ports.
Fuel injection system
The fuel pump carries gas from the tank, through a fuel filter, to the engine
where fuel injectors emit a precisely
timed spray of gas into the intake port.
Cooling system
Engines get very hot during operation and
require a cooling system. The cooling system basically consists of a radiator, water pump and cooling channels. Cool water from the radiator is pumped through cooling channels that go around the hot cylinder blocks, cooling the engine in the process. This hot water then passes through the radiator and is cool again for recirculation.
The radiator has a network of small tubes and fins. As hot water passes through these tubes it is cooled with the aid of fins and radiator fans.
Electrical system
This is a complex system that basically consists of the battery, fuses, wiring , coils, spark plugs, and the alternator.
The battery provides the initial electrical connection that enables the car to start. The alternator is like an electric generator. Once the car engine starts running, the alternator basically charges the battery and generates the electricity required for the whole car to function properly
lubricating system
Just like the cooling system, the engine lubricating system basically consists of , engine oil, oil storage, oil lubricating channels, oil filter and oil pump.
The oil pump keeps oil properly
pressurized and flowing.
It pumps the motor oil to lubricate, cool, clean, prevent corrosion of the engine.
The oil filter keeps oil clean from contaminants.
Exhaust system
The exhaust manifold collects gases
from multiple cylinders into one pipe.
Exhaust flows through the catalytic converter, which captures toxic chemicals in engine exhaust. And then out through a muffler that reduces exhaust noise.
