Abstract: An apparatus for distributing wash liquid to a spray device which is located above a dish-supporting rack in a dishwashing appliance, the apparatus including a vertical hollow tower having an open lower end fixedly attached to the rack, means for rotatably mounting the spray device onto an apertured upper end of the tower so that there is fluid communication between the tower and the spray device, and a fluid-expansible coupling member located below the rack and having an upper opening below and substantially concentric with the open lower end of the tower. A hub assembly supports the coupling member on a pump means which forces wash liquid through the hub assembly and into the coupling member to expand it into a sealing contact with the tower at the open lower end of the tower so that fluid flows through the tower to the spray device.