Intake air preheating

The intake air preheating is a technical device, primarily for carburetor engines . It is intended to prevent the formation of condensation or ice in the engine and is particularly important in the cold start phase .

Working principle

Due to the evaporation of fuel components produced in the region of the carburetor evaporative cooling . This can cause moisture from the intake air to condense and freeze in the intake path and on the carburetor nozzles. The ice prevents the carburetor from working properly. In addition, some of the fuel condenses on the intake pipes, making the mixture leaner and possibly causing cold running difficulties. In addition, the re-condensed fuel can also get into the lubricating oil and thus impair its lubricating properties.

Technical implementation

A widespread possibility is to suck in air from the area of ​​the exhaust manifold , which heats up very quickly when the engine is running. Ideally, however, the air in the intake tract is only heated when the outside temperature is low, otherwise the cylinder charge and thus the output would decrease in warm weather. This can be avoided by a thermostatic control.

See also

• Intake tract
• Elbow
• Charge air cooling
• Water injection
• Degree of delivery

swell

• Carburetor and injection systems , Thomas Becker, Motorbuchverlag Stuttgart, ISBN 3-613-01238-3 .