The left-hand camshaft K 42101, located on the flywheel side, is a major timing and control component of the Adriadiesel/Jugoturbina/Zgoda/Sulzer ZV40/48 engine. Its principal function is to convert precisely synchronized rotary motion into the controlled mechanical actions required by the engine systems associated with the camshaft, ensuring that these functions occur at the correct points in the operating cycle. The geometry and angular position of the individual cams, together with the straightness, bearing surfaces, dimensional accuracy, and surface condition of the shaft, are critical to maintaining correct timing and consistent engine performance. During operation, the camshaft is exposed to repeated contact loads, torsional forces, bearing loads, vibration, and long periods of continuous service, requiring high mechanical strength, wear resistance, effective lubrication, and precise alignment. Regular inspection of cam profiles, journals, drive connections, lubrication passages, and associated components is important for detecting wear or damage before timing accuracy is affected. By providing precise and repeatable mechanical control on the flywheel side of the engine, the K 42101 left-hand camshaft contributes directly to correct engine timing, stable performance, operational reliability, and the long service life of the ZV40/48 engine.