We come first to the ignition system of an internal combustion engine that depends on the type of engine and the fuel being used in the unit. Diesel engines are ignited by compression heating while petrol engines are usually ignited by a spark that is precisely timed.
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. Note that almost all engines in gasoline are of this kind, while diesel engines timing is controlled in a precise manner by the injector and pressure pump.
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. Note that the biggest number of compression ignition engines are those of diesels where the fuel is mixed with the air after reaching ignition temperature.
As there is a large area present of fuel to the oxygen in air, fuels would burn faster and more efficiently. To create a fuel air mixture, liquid fuels must be atomized and this is traditionally done with a carburetor in petrol engines and with fuel injection in diesel engines. Fuel injection is also used by many modern petrol engines today although there is difference in the technology. See page for more info.
In order to supply fuel into the cylinder, the use of carburetor is used in simpler reciprocating engines. From the mid 1980s, carburetor technology in cars have attained a very high degree of precision and sophistication, but lost out on the cost and flexibility to fuel injection. Small engines though still remain to use the simple forms of carburetor, like lawn mowers and the more sophisticated forms of engines used in small motorcycles. Read more here.
Fuel injection systems have been used mostly by automobiles with larger gasoline engines. The system of fuel injection has been always used in diesel engines and this is because the timing of the injection would kick off and controls the combustion.
In the case of autogas engines, it uses either fuel injection systems or open or closed loop carburetors.
Many internal combustion engines now require a fuel pump. 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.
In the case of a four stroke engine, there are key parts that form the parts of the engine, and these are the crankshaft, connecting rod, one or more camshafts, and valves.
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