An internal combustion engine has an ignition system which would depend on the type of engine and fuel used of the unit. A precisely timed spark would ignite petrol engines, while it is through compression heating that would ignite diesel engines.
In the case of a spark ignition engine, ignition is by a mixture of an electric spark from a spark plug, the timing of which should be controlled precisely. While this is the ignition type for almost all gasoline engines, the timing on the other hand for diesel engines is through a precise and controlled pressure pump and injector.
Ignition happens when the temperature of the fuel/air mixture is taken over by the autoignition temperature because there is heat generated during the compression stroke of which air is compressed. Diesels composed the vast majority of compression ignition and this is because fuel is mixed with the air once the air has reached ignition temperature.
As there is a large area present of fuel to the oxygen in air, fuels would burn faster and more efficiently. The traditional way to atomize liquid fuels, which is needed to create a fuel air mixture, is to have it done with a carburetor in petrol engines and with the fuel injection in diesel engines. Although the technology is quite different, many of the modern petrol engines use fuel injection also.
The supply of fuel into the cylinder of a simpler reciprocating engines would use a carburetor still. Carburetor technology in vehicles have reached a level of very high sophistication and precision, but in mid 1980s, it lost out to fuel injection in terms of cost and flexibility. Simple forms of carburetor maintained its use in small engines in forms of lawn mowers and in small motorcycles.
Fuel injection systems have been used mostly by automobiles with larger gasoline engines. The timing of the injection initiates and controls the combustion, and this is why diesel engines have always used fuel injection system.
Where autogas engines is concern, it is fuel injection system is used or the open closed loop carburetors.
A fuel pump is what most internal combustion engines require. In order for the combustion chamber to be overcome, in the case of diesel engines, an all mechanical precision pump system is used and this would produce a timed injection directly into the chamber for combustion.
Among the parts of the engine that are the key parts of a four stroke engine are as follows, the crankshaft, connecting rod, one or more camshafts, and valves.