Many people believe that the entire engine is just a big block that does all the work. That might be true, but what exactly is in this block that gets such a large machine to move and function?
Let’s start with the driver. The driver would apply the acceleration pedal. This pedal forces fuel into the combustion chamber. Depending on the type of car you have will depend on the type of fuel you will fill the tank with. In this case, we will be dealing with a petrol engine.
Once you force the petrol into the combustion chamber, a valve will open up to allow the combustible liquid into the cylinder head. There are usually two valves per cylinder head as there has to be an inlet and outlet for the car to move and transfer gases.
The valves will close and allow no extra air or petrol to enter whilst the piston compresses the petrol. After the piston reaches B.D.C or bottom dead centre, the spark plugs will ignite the petrol. The piston will then push the burnt gases out of the outlet valve ready for the next bit of fuel to enter its chamber.
Around each piston is a set of piston rings. These rings seal any spaces that could let in air and allow the piston to move smoothly. They also prevent oil from leaking from the sump into the combustion chamber. Each piston is linked to a connecting rod that gets attached to the crankshaft with a bearing.
The crankshaft will convert the pistons up and down movement into rotational movement. In other words, this is the part that makes the car move forwards and backwards. Each time time-aligned pistons go down, the crankshaft rotates.
The ignition system is connected to a timing system that sets off specific spark plugs at a time. In a four cylinder engine, it would be the first and third spark plug that ignites first and then the second and fourth plugs.
After the engine has gone through the cycle and reaches the fourth cylinder head, the second valve will open up thus releasing the gases to the exhaust manifold either going to a turbo or straight to the exhaust pipe.
The car has many systems functioning together to make it the ultimate machine. Apart from the engine, there is the braking system, the electronic system and the clutch system. Usually when you take your car in for a service, the mechanics would check if the car needs any clutch, engine or brake repairs before sending the machine off to the specific specialist.