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How A Car Works



Inside A Car Cylinder

Inside A Car Cylinder

Four Stroke Combustion Cycle

Four Stroke Combustion Cycle





The bottom of each piston is attached to the crankshaft.




What Are Revolutions Per Minute?



Car Engine Uncovered

Car Gears - Transmission

The Transmission





Other Key Car and Car Engine Components

Alternator: turns mechanical energy into electrical energy. This energy powers a car's electrics, from lights to wipers. It also recharges the car battery. A belt that rotates once the engine is on powers it.

Brakes: cars use either drum or disc brakes. Disc brakes use a calliper to press onto the disc of the wheel in order to slow the wheel down. Drum brakes work on the same principle however a drum brake presses against the inside of the drum.

Camshaft: controls the opening and closing of the intake and exhaust valves.

Cooling System: car engines produce a lot of heat. This heat needs to be controlled. To do this water is pumped through passages that surround the cylinders and then through the radiators to cool down.

Distributor: operates the ignition coil making it spark at exactly the right moment. It also distributes the spark to the right cylinder and at the right time. If the timing is off by a fraction then the engine won't run properly.

Exhaust System: once the fuel-air mix has been burnt the remaining gas enters the exhaust system and is expelled from the car. If a catalytic converter is present the exhaust gas passes through it and any unused fuel and other certain chemicals are removed.

Handbrake: this is a separate system from the foot brake. As a rule it is mounted on the floor of the car and is connected by a cable to the two rear wheels.

Head Gasket: the cylinder head (a block that seals all the tops of the cylinders) and the engine block (which contains the main bodies of the cylinders) are separate components that need to fit seamlessly together. The head gasket is a piece of metal that sits between them and connects them.

Oil: a car engine consists of many moving parts. Oil lubricates these parts and allows them to move smoothly. In most car engines oil is pumped out of the oil pan through a filter that removes any dirt and then is squirted under high pressure onto the bearings and cylinder walls. The oil then trickles down to the sump where the process starts over.

Regulator: regulates the amount of energy in the alternator.

Shock Absorbers: also known as dampers, are fitted between the car's body and axle in order to prevent excessive rolling and bouncing of the car body during motion.

Suspension System: counteracts the effects of hitting bumps in the road. Without such a system a car would veer of course every time the tyres hit a bump or pothole. The system comprises of springs and shock absorbers. The springs absorb any of the energy released when the tyres roll over a bump and the shock absorbers absorb the energy from the springs. This keeps the main body of the car steady and stable.

Timing Belt: a belt connected to both the camshaft and crankshaft ensuring that they work in time with each other.

What is the difference between a Petrol and Diesel Engine?

In petrol engines fuel is mixed with air and then forced into the cylinders where the fuel-air mix is compressed by the pistons and ignited by spark plugs. In a diesel engine the air is compressed before the fuel is added to it. When air is compressed it heats up. This means that when the fuel is added to the compressed air it is very hot and the fuel-air mix ignites automatically. So there are no spark plugs in a diesel engine as pressure is used to ignite the fuel-air mix.