Which option describes throttle ice prevention?

• A. Using carburetor air heating systems.
• B. Turning the engine off.
• C. Pouring water into the intake.
• D. Raising the frame height of engine.

Answer: (A)

Throttle ice occurs when moist air entering the carburetor cools and freezes, especially around the venturi and throttle plate, causing icing that blocks airflow and reduces power. To prevent this, heat the air before it reaches the carburetor. Carburetor air heating systems provide heated air—taken from around the engine or exhaust—into the carburetor intake. Rising the air temperature reduces moisture condensation, melts any ice that forms, and keeps the throttle and mixture functioning smoothly. The other options don’t address ice formation: turning the engine off stops operation; pouring water into the intake would worsen icing and damage the engine; raising the engine’s frame height has no effect on carburetor icing.