Indirect Injection
      In an internal combustion engine, the term indirect injection refers to a fuel injection where fuel is not directly injected into the combustion chamber.An indirect injection diesel engine delivers fuel into a chamber off the combustion chamber called a prechamber,The prechamber is carefully designed to ensure adequate mixing of the atomized fuel with the compression-heated air. This has the effect of slowing the rate of combustion, which tends to reduce audible noise. In addition, it softens the shock of combustion and produces lower stresses on the engine components. The addition of a prechamber, however, increases heat loss to the cooling system and thereby lowers engine efficiency.

Advantages of indirect injection combustion chambers

1. The injection pressure required is low
2. Also the question of injection direction becomes less importance
3. Indirect injection is much simpler to design and manufacture; much less engine and injector development is required and the injectors themselves are less tightly toleranced and more reliable.

Disadvantages

1. Heat plugs are required for pre heating the chambers
2. Specific fuel consumption is high because of heat loss to large exposed areas and pressure loss due to air motion through the throats.
3. Indirect-injection diesel engines are harder to