An engine is a strong structure, composed of two main parts joined by bolts.

The head is the top of the engine, containing the valves and recesses, called combustion chambers, where fuel is burned. Cylinder block is the bottom of the engine, which houses the pistons in cavities of the block, within which the pistons move up and down on rods. The power generated is transmitted to the crankshaft, which is connected in the bottom of the block to various supports housed in the main bearings.

A container bolted to the bottom of the block serves as a reservoir of engine oil for the crankcase, and a punched metal cover for the valves is installed on the head.

The combustion delivery valve chamber is a cylinder closed at one end and within which a piston slides very tightly. The position of the piston up and down in the chamber varies the volume between the top of the piston and the chamber walls. The bottom of the piston is connected by a rod to the crankshaft, which converts the linear motion of the piston into the rotary motion of the crankshaft.

The fuel pumping system of an internal combustion engine consists of a fuel tank, a fuel pump and a device called a carburetor that vaporizes or atomizes liquid fuel. In multi-cylinder engines, the vaporized fuel is introduced into the cylinders through a tube called the branch manifold.

All engines must have a way to ignite the fuel inside the cylinder. For example, in the ignition system of gasoline engines there is a component called the ignition coil, which is a high voltage transformer, connected to a switch that interrupts the primary current to induce a high-voltage surge.

Since combustion produces heat, all plunger engines must have some kind of cooling system. Certain stationary engines of cars, planes and outboard engines are cooled with air. The cylinder engines using this type of system have on the outside a set of metal sheets that emit heat produced in the cylinder. Other engines use water cooling systems, where the cylinders are in a casing filled with water, which the automobile circulates by a pump. The water is cooled by passing it through the blades of the radiator.

It is important that the liquid used to cool the engine is not ordinary water, because combustion engines regularly work at temperatures higher than the boiling point of water. This causes high pressure in the 8N7005 cooling system, which results in faulty gaskets and seals. A coolant is used in the radiator. The coolant does not boil until a much higher temperature than water, and does not freeze until a much lower temperature.