This final thesis investigates the issue of repairing the electric ship winch Quick S.p.A G1000. Through a detailed analysis of the winch's structure, fault diagnosis, manufacturing of a replacement part for the broken shaft, and verification of material strength and heat treatment, it demonstrates the importance of an expert approach in solving technical problems. The winch malfunction was identified as a result of sudden breakage, which could have arisen from manufacturing irregularities or design flaws. A new shaft was fabricated that meets the necessary technical standards and safety requirements, employing calculations of force, torque, and material strength. The assembly of the replacement shaft was carried out successfully, with heat treatment applied to improve the mechanical characteristics of the material, and the winch was thoroughly tested to ensure its proper functioning. This thesis illustrates the significance of an engineering approach and expertise in the process of repairing technical devices, emphasizing the collaboration of experts in the field of mechanical engineering. Through a practical example of repairing a ship's winch, this thesis provides insight into the process of solving technical problems and underscores the importance of precision and analytical thinking in engineering challenges.