Abstract: In order to obtain a self-control of the working pistons with a simple, space-saving construction in the case of a radial-piston engine having pot-shaped pistons which are in contact with the circumference of an eccentric shaft and into which there engages in each case a guide body mounted radially outside on the housing in floating arrangement, and having fluid ports in the cylinder cover for the inflow and outflow of the pressure fluid, a control element (15), connected in jointed manner to the guide body (5), is adjustably disposed in the cylinder cover (9) or a corresponding component of the housing, for controlling the inflow and outflow ports (19, 20).