Which of the following activities is typically part of second-degree engine repair?

The correct answer reflects the scope of second-degree engine repair, which generally includes the replacement of specific components that are subject to time limits based on usage or operational requirements. Time-limited components are parts that have a defined service life due to wear and performance limitations. This repair activity focuses on ensuring that the engine continues to operate effectively while adhering to safety and reliability standards.

Second-degree engine repair does not extend to a complete overhaul or enhancement of the engine design, which would be more complex and would typically fall under first-degree repairs or specialized modifications. The installation of new accessories or modifications for performance enhancement also involve different sets of regulations and maintenance goals, as they might change how the engine operates or its compatibility with existing systems.

By focusing on the replacement of time-limited components and gearboxes, this approach ensures that the engine maintains its operational integrity without the need for a more extensive overhaul, making it a crucial part of ongoing engine maintenance.