Abstract: An agitator assembly for mounting in a wall of a storage tank that includes a body having a rotatable shaft extending therethrough. The body includes a duct having a diameter that is larger than the diameter of the shaft to allow passage of a fluid therebetween. An impeller is secured to one end of the shaft and a collar is secured to the other end. A bushing is provided between the body and the shaft and allows passage of a fluid during a cleaning cycle. A motor assembly is attached to the shaft and provides power for rotation of the shaft. A resilient member is provided over the shaft between the motor assembly and collar to control axial movement of the shaft. During a cleaning cycle, fluid pressure overcomes the biasing force of the compressible member permitting the fluid to escape the body to effectively clean the impeller.