Using the wrong propeller size can lead to significant engine performance issues, which is why this answer is correct. A propeller that is either too large or too small for the boat can cause the engine to operate outside its optimal performance range. If the propeller is too large, the engine may struggle to reach the intended RPMs (revolutions per minute), causing it to underperform and potentially overheat. Conversely, a propeller that is too small may allow the engine to exceed its maximum RPMs, which also presents risks such as mechanical damage and reduced efficiency.
In addition to engine overheating, incorrect propeller sizing can prevent the boat from reaching its designed speed, leading to poor performance on the water. Choosing the appropriate propeller size is essential for maintaining safe and effective operation, ensuring optimal fuel efficiency, speed, and overall handling. Understanding these dynamics is crucial for any boater looking to maximize their vessel's performance and longevity.