A radial piston hydraulic motor comprising a box frame with a cam ring connected thereto, pistons (13a1, 13a2...) in a piston frame and press rollers (14a1, 14a2...) in the pistons, which press rollers can be pressed by means of the pressure of a hydraulic fluid, such as hydraulic oil, against an inner surface of the cam ring, a working pressure inlet passage for the hydraulic fluid under working pressure and a return passage for the hydraulic fluid which is not under working pressure, from which working pressure inlet passage and the return passage the hydraulic fluid is conducted to distribution valve, the distributor valve comprising bores through which hydraulic fluid can be conducted into and out of passages in the piston frame and further in connection with the pistons, an interior space for receiving hydraulic fluid, a free-rotating valve arranged to disengage the motor to be in a free-rotating state and engage the motor to be in a drive-state by controlling the pressure in the working pressure inlet passage and in the return passage, and springs (U1, U2...) are arranged to press the pistons (13a1, 13a2...) and the press rollers (14a1, 14a2...) associated therewith to a bottom position and out of contact with the cam ring wherein the piston frame is connected to a central shaft, char act e r i zed in that the piston frame comprises connections between the interior space and passages, and a shutter valve is provided within each connection for controlling the hydraulic fluid flow through the connection between the passages and the interior space, wherein the shutter valve is arranged to allow hydraulic fluid to flow from the passage into the interior space, when the pressure in the working pressure inlet passage, in the return passage and in the interior space is equal, i.e. the motor is in free-rotating state, and the shutter valve is arranged to be in a closed position, when the working pressure inlet passage is under working pressure and/or the return passage is under counter pressure. a box frame with a cam ring connected thereto, pistons (13a1, 13a2...) in a piston frame and press rollers (14a1, 14a2...) in the pistons, which press rollers can be pressed by means of the pressure of a hydraulic fluid, such as hydraulic oil, against an inner surface of the cam ring, a working pressure inlet passage for the hydraulic fluid under working pressure and a return passage for the hydraulic fluid which is not under working pressure, from which working pressure inlet passage and the return passage the hydraulic fluid is conducted to distribution valve, the distributor valve comprising bores through which hydraulic fluid can be conducted into and out of passages in the piston frame and further in connection with the pistons, an interior space for receiving hydraulic fluid, a free-rotating valve arranged to disengage the motor to be in a free-rotating state and engage the motor to be in a drive-state by controlling the pressure in the working pressure inlet passage and in the return passage, and springs (U1, U2...) are arranged to press the pistons (13a1, 13a2...) and the press rollers (14a1, 14a2...) associated therewith to a bottom position and out of contact with the cam ring wherein the piston frame is connected to a central shaft, char act e r i zed in that the piston frame comprises connections between the interior space and passages, and a shutter valve is provided within each connection for controlling the hydraulic fluid flow through the connection between the passages and the interior space, wherein the shutter valve is arranged to allow hydraulic fluid to flow from the passage into the interior space, when the pressure in the working pressure inlet passage, in the return passage and in the interior space is equal, i.e. the motor is in free-rotating state, and the shutter valve is arranged to be in a closed position, when the working pressure inlet passage is under working pressure and/or the return passage is under counter pressure.