Abstract: In a marine vessel hull cleaning device wherein a floating platform has spaced ways between which a vessel to be cleaned passes lengthwise, at least one transom scrubbing brush is supported from the platform, arranged to move clear of the vessel when the vessel moves between the ways, to move into transom engaging position and to be held in engagement with the transom of the vessel. Preferably, the vessel is both held in a position to permit the transom scrubbing brush to engage it and is moved up and down relative to the transom scrubbing brush by bottom scrubbing brushes which rotate in such a way as to tend to move the vessel astern.

Abstract: In a marine vessel bottom cleaning device wherein a floating platform has spaced ways between which a vessel to be cleaned passes lengthwise and scrubbing devices are supported on the platform, at least two, elongate scrubbing devices, spaced from one another lengthwise of the ways, extending in a direction generally athwart the ways and toward one another, and in at least one position overlapping one another across the lengthwise path of the vessel, the scrubbing devices being selectively movable relative to one another from the position at which they overlap one another along the lengthwise path of the vessel in a direction outboard of the vessel and away from one another. The entire scrubbing device can be raised and lowered with respect to the platform.