Hydrostatic motor for starting an internal combustion engine

The hydrostatic power train (7) has a suction side to intake pressure medium from a container (9). The power train supplies a load (V) in a supply line (10). The power train is provided with a swing spring (55) to operate as a motor and a pump. A displacement body volume positioning unit (50) controlling the displacement body volume of the power train is applied in the position with the maximum displacement body by the swing spring.