What happens to engine cooling when using a carburetor economizer system at cruise settings?

When using a carburetor economizer system at cruise settings, it aids in engine cooling. The primary function of the economizer is to provide a richer fuel mixture during cruise conditions, which can help maintain engine temperature by enhancing the cooling effect of the fuel.

This occurs because more fuel in the mixture results in greater fuel evaporation, which absorbs more heat from the engine components, thus improving the overall cooling effect. Additionally, a rich mixture helps in efficient combustion, preventing the engine from running too hot and ensuring it operates within optimal thermal limits.

The other options suggest either a decrease or no effect on cooling, which does not align with the mechanics of how a carburetor economizer functions in maintaining engine temperature during steady-state operation.