Abstract: The wet-running submersible motor comprises a shaft and an electrical rotor arranged thereon, both being arranged in the rotor space of the motor. The shaft is formed hollow either on its longitudinal section on the pump side or over the whole length. On the pump side the shaft surrounds a sealing formation for sealing the rotor space of the motor with respect to the pump. Furthermore the hollow shaft is provided with radial flow passages in order to circulate fluid in the rotor space of the motor. Through the hollow shaft fluid is also led to the pump side, for which the shaft end on the pump side is provided with a fluid passable functional unit. The functional unit is formed so that it at least allows a fluid flow towards the pump side in order to bleed the rotor space and to reduce excess pressure in the rotor space which is subsequently filled with delivery fluid via the sealing formation, by way of fluid exit towards the pump side.