Which of the following best describes a consequence of a lower cooling efficiency?

A lower cooling efficiency in a diesel engine can lead to engine overheating. Cooling efficiency is crucial for maintaining optimal operating temperatures within the engine. When the cooling system fails to remove heat effectively, the engine can reach temperatures that exceed safe operational limits, causing damage to engine components such as the cylinder head, gaskets, and even the engine block itself.

Overheating can also lead to further complications, including reduced engine performance, increased wear and tear, and potentially catastrophic failures like a blown head gasket or warped cylinder heads. Monitoring and maintaining the cooling system is essential for overall engine health and performance, making it structured to prioritize effective temperature regulation. The other choices do not directly relate to a consequence of lower cooling efficiency, as better fuel economy, increased horsepower, and improved ignition timing are typically not outcomes of ineffective cooling.