A method for collecting garbage from a surface includes providing a motor-sweeper including a sweep broom. A rear guide is provided between the sweep broom and the collecting container extending downwards from the collecting container close to the sweep broom. The sweep broom rests with the guide assembly onto the surface, and the sweep broom is rotated in order to collect and convey the garbage into the collecting container. The rotation of the sweep broom causes the garbage to be swept forwardly and upwardly with respect to the forward motion of the motor-sweeper. In response to the bristles of the sweep broom wearing, the sweep broom is moved toward the surface and the guide assembly and the rear guide are moved towards the sweep broom so as to maintain uniform spaces between the sweep broom and the guide assembly, and the sweep broom and the rear guide.