A valve operator assembly for a valve includes a valve body and an axially moveable valve translating member, a housing mounted on the valve, an input member rotatably mounted with respect to the housing, and a transmission mechanism. The transmission mechanism including a translating element connected to the valve translating member and a rotating element connected to the input member. The transmission mechanism configured to convert applied rotation of the input member into axial translation of the translating element. The valve operator assembly providing a spacing element having a tubular shape defining an axial bore through which passes the valve translating member and the translating element of the transmission mechanism. The spacing element connected by intermediate fixing means on the valve body on one end and on the housing on the other end to define cooperating mounting surfaces between the spacing element.