Carb Icing Refresher for Cold, Damp Days
Carb icing is most common on cold, damp days but possible from -10°C to +25°C – use carb heat below the green arc and watch for it in SCADIE checks.
1 min readKapiti Aero Club safety team
The colder months are a good time for a carburettor icing refresher.
Carb ice builds up inside the carburettor, restricting airflow and causing the engine to run rich. The result can be rough running, a drop in RPM and a loss of power.
While carb icing is more common in winter, it can occur in temperatures from around -10°C to +25°C. The temperature inside the carburettor can be much colder than the outside air because of the venturi effect and fuel evaporation, so even a mild day can produce icing conditions.
If you suspect carb ice, apply carb heat. The engine may run rough at first as the ice melts and passes through the engine, but normal operation should return once the ice has cleared.
Remember to:
- use carb heat below the green arc (below 1900 RPM in the C152)
- check it during your run-up
- stay alert for signs of icing during your SCADIE checks
