Crankshaft bearings, commonly associated with code H33016, play a vital role in supporting the crankshaft within the engine block, enabling smooth rotation under heavy loads. In the MAN L21/31, these bearings endure significant mechanical and thermal stresses. Failure or excessive wear in crankshaft bearings can lead to severe engine damage. Therefore, consistent inspection, lubrication, and prompt replacement are critical for maintaining engine health and avoiding costly repairs.