A carburetor is a device in an engine fuel system, which mixes fuel with air and supplies the combustible mixture to the intake manifold. In the past, carburetors were part of most fuel systems. However, most vehicles nowadays have a fuel-injection system. As air passes through the carburetor, fuel is drawn out of the float bowl and sprayed into the airstream in carefully measured amounts.
- In most engines, a mixture of 14.6 parts air to one part gas ensures maximum vaporization and combustion of the fuel. Hence, the carburetor varies the proportion of fuel and air to suit different operating conditions. For example, a rich mixture of about 9 pounds of air for every pound of gasoline is delivered for starting initial warm-up and accelerating.
- A relatively lean mixture of about 15 pounds of air for every pound of gasoline is delivered for normal over-the-road operation.
Constant Vacuum Carburetors
- Constant Vacuum Carburetors are a type of carburetors wherein a throttle cable is affixed to the cable plate; is also commonly called variable choke carburetors
- Large emission of hydrocarbons is being produced from the raw gasoline that enters this type of carburetor.