What happens to cooling fins without regular cleaning in an air-cooled engine?

When cooling fins are not regularly cleaned in an air-cooled engine, they can become coated with dirt, dust, or debris, which obstructs airflow. This accumulation of contaminants reduces the surface area available for heat dissipation, leading to poor thermal management within the engine. As a result, the engine may run hotter than intended, which can cause overheating and potential damage to engine components. Regular cleaning ensures that the fins remain effective in transferring heat away from the engine, maintaining optimal operating temperatures and overall engine efficiency.