Suction excavating machine consisting of a carrier vehicle (5) equipped with a motor (15) on which are mounted a machine compartment equipped with waste and debris pumping organs as well as a tank capable of tilting transversely around a horizontal tilting axis between an upright position or working position and a tilted position or emptying position, characterized in that the waste and debris pumping organs are constituted by a single high-power suction pump (1), and by means for driving the rotation shaft (6) of this suction pump (1) comprising hydraulic drive organs and mechanical drive organs actuated from the motor (15) of the carrier vehicle (5), as well as clutch organs allowing selective and automatic coupling and uncoupling of these drive organs and the rotation shaft (6) of the suction pump (1) under controlled speed conditions.
