Sneak into the Fuel system of Petrol Engine

After getting to know about the types of engines and their working, its time to understand what makes the engine accept the fuel we supply. 

In a  Petrol  engine a component called "Carburetor" prepares a  homogeneous (Uniform) mixture of air and petrol before sending it to the intake valve. The main criteria to be noted is that, the combustible air fuel mixture must be in proper proportion before admitting it to the engine cylinder. This process is known as carburetion. Main reason for an efficient petrol engine is the ratio  Air- Fuel sent into the engine. 

So now,let us look at types of Air Fuel Mixture.

• Stoichiometric or Chemically correct Mixture
• Rich Mixture 
• Lean Mixture

1. Stoichiometric or Chemically correct Mixture

Chemically correct or stoichiometric mixture is the fuel which has sufficient amount of air for complete combustion of the fuel. The correct air fuel ratio  of petrol engine is 14.7:1 or  15:1 which means 15 parts of air is enough to completely covert 1 part of fuel to carbon dioxide and water.

2.Rich mixture 

A mixture which has less air than the required amount is called rich mixture Air fuel mixture of 10:1 indicates that 10 parts of air is not enough to do combustion of 1 part of fuel . It  may give cooling effect to combustion chamber but it will waste fuel.so it is not preferable to use as it is less efficient.Rich mixture may enter due to malfunctioning oxygen sensor or  malfunctioning of fuel pressure regulator or many more reasons.. 

3.Lean Mixture 

A lean mixture contains more air than a required level. If AFR(Air Fuel Mixture) is 17:1 then it means more air to do combustion of 1 part of fuel. It may be due to clogged fuel filter or malfunctioning oxygen sensor or less pressure fuel or many more reasons..