Which device is mounted at the entrance and allows the engine to rotate freely before starting?

Which device is mounted at the entrance and allows the engine to rotate freely before starting?

• A. Flywheel
• B. Starter motor
• C. Clutch
• D. Barring device

Answer: (D)

Rotating the engine by a small amount without actually starting it is done with a barring device. This tool engages the flywheel at the front of the engine so the crankshaft can turn freely, allowing you to pre-rotate the engine to check for binding, distribute lubrication, and position it for a smooth start. It’s mounted at the crank end and is used specifically to rotate the engine without the full starting system engaging. The flywheel is just the rotating mass that helps smooth torque, the starter motor is what actually starts the engine, and a clutch connects or disconnects the engine from the drivetrain. So, the barring device is the correct choice.

Rotating the engine by a small amount without actually starting it is done with a barring device. This tool engages the flywheel at the front of the engine so the crankshaft can turn freely, allowing you to pre-rotate the engine to check for binding, distribute lubrication, and position it for a smooth start. It’s mounted at the crank end and is used specifically to rotate the engine without the full starting system engaging. The flywheel is just the rotating mass that helps smooth torque, the starter motor is what actually starts the engine, and a clutch connects or disconnects the engine from the drivetrain. So, the barring device is the correct choice.