Abstract: A fluid operated wash brush is provided. The wash brush includes a casing having a downwardly opening top cover. The casing includes a liquid inlet for connection to a fluid supply. The wash brush also includes a rotary wash brush and a mounting shaft supported by the casing for relative rotation on which the rotary wash brush is carried. A retention mechanism is carried on a distal end of the mounting shaft for releasable engagement and disengagement with the rotary wash brush.