Describe the procedure for performing a manual rotation of the engine for inspection.

• A. Start engine and spin at full speed
• B. Remove the rotor and inspect
• C. Apply lubricant and spin with high speed
• D. Ensure lockout, depress controls, attach appropriate tool, rotate rotor slowly by hand or with a torque-limiting device, observe smooth movement and absence of contact

Answer: (D)

Manually rotating the engine for inspection is about confirming the rotor can move freely and that there’s no interference between moving and stationary parts. Start by ensuring the system is safely isolated—lockout the relevant controls, fuel, and power to prevent any accidental startup. Depress any controls that could enable rotation or engine operation, so nothing energizes during the check. Attach the appropriate hand tool or a torque-limiting device to the rotor to maintain control and protect components from excessive torque. Rotate the rotor slowly by hand (or with the torque-limiting device) and feel for smooth, even movement without any stiff spots or binding. As you turn, watch for abnormal contact or rubbing between parts such as bearings, gears, seals, and blade rows; any sign of interference means a fault that needs attention before further inspection or operation. This method protects the engine from damage during inspection and helps verify that lubrication and clearances allow the rotor to turn without abnormal resistance.