What are five negative outcomes from using too rich of a mixture?

Using a too rich mixture in an aircraft engine can lead to several negative outcomes, which directly affect engine performance and efficiency. Among these, engine damage and airflow issues stand out prominently.

When the fuel-air mixture is excessively rich, meaning there is too much fuel relative to air, it can cause incomplete combustion. This incomplete combustion not only hampers the engine's overall efficiency but can also lead to carbon buildup. Over time, this carbon can damage various engine components, impacting the overall health of the engine.

In addition, a rich mixture can obstruct optimal airflow within the combustion chamber, resulting in inefficient combustion processes. The engine components may not cool down properly due to the increased fuel content, leading to potential overheating and decreased engine lifespan.

While other options mention problems like rough running and power loss or spark plug fouling, these are often more direct consequences of an overly rich mixture rather than broader issues related to airflow and systemic engine damage. Fuel wastage typically ties back to inefficient combustion rather than a direct structural problem with the engine itself. Thus, understanding the more systemic issues associated with rich mixtures helps pilots manage engine performance more effectively.