Abstract: According to an example aspect of the present invention, there is provided a steering system of an azimuthing propulsion system, the steering system comprising at least one hydraulic motor configured to operate an azimuthing system of a propulsion unit, the propulsion unit being arranged outside a vessel, a fluid cycle from the at least one hydraulic motor via a separate hydraulic overload protection unit and back to the motor, the overload protection unit comprises a pressure relief unit and a heat management unit, and wherein the pressure relief unit comprises a pressure relief valve, and the heat management unit comprises a heat storage, a heat exchanger, or a combination of both, and wherein the fluid cycle comprising the overload protection unit is configured to at least partially absorb heat generated during turning of the propulsion unit.