Carburetor is a mechanical device in internal combustion engines responsible for mixing fuel and air in appropriate ratios and delivering the mixture to the cylinders. It is commonly used in gasoline engines. The vaporization of fuel and the provision of the air-fuel mixture required by the engine are among the primary functions of the carburetor. Although it has largely been replaced by injection systems with the advancement of automotive technology, it still exists in certain types of engines.

Historical Background

The first functional version of the carburetor was developed by Karl Benz in 1885 and was patented the following year. Additionally, in 1893, Hungarian engineers János Csonka and Donát Bánki developed a similar mechanism. British engineer Frederick William Lanchester contributed to the field by developing a wick-type version of the carburetor. The first gasoline-powered car, produced in 1896, operated with this system; a 1,600-kilometer tour completed in 1900 demonstrated the applicability of this technology.

^{How Carburetors Work (Donut)}

Carburetors were widely used in gasoline vehicles until the late 1980s. In the United States, their use in automobiles began to decline by 1990; among the last models to feature carburetors were the Oldsmobile Custom Cruiser, Buick Estate Wagon, and certain Ford Crown Victoria models. A light commercial vehicle produced by Isuzu in 1994 is recorded as one of the final applications of the carburetor system. In Russia, Lada continued to use carburetors in production until 1996.

Working Principle

The carburetor operates based on Bernoulli's principle. As air speeds up through a narrowing, static pressure decreases while dynamic pressure increases, and this pressure difference enables the fuel to be drawn in. The throttle valve does not directly control the fuel flow but instead regulates the amount of air being drawn in, thereby indirectly controlling the fuel ratio.

A carburetor basically has a venturi structure. The constriction in this structure increases the air velocity, creating a low-pressure zone where fuel mixes with the airflow. Fuel is injected through small holes (jets) located in this region.

Advantages and Disadvantages

The simple design and low cost of carburetors have made them favorable for use in small engines. However, in terms of fuel efficiency and emission control, they are inferior to injection systems. Particularly in cold weather, their initial start-up performance is weak, and the mixture ratio cannot be adjusted with full precision.