A propulsion assembly for an endoscope includes a support sleeve and an endless track device. A clamping sleeve is contained in the support sleeve. Male and female threads cooperate for moving the clamping sleeve between operative and non-operative states upon rotation of the clamping sleeve. The operative state is on a side of a proximal direction from the non-operative state along a central axis. A sealing device is contained in the support sleeve, has a C-shape in a resiliently deformable manner, is disposed around the endoscope and between the clamping sleeve and a receiving surface. The sealing device is pushed by the clamping sleeve when the clamping sleeve is in the operative state, for squeezing the endoscope by radially compressing thereabout, and released from push of the clamping sleeve when the clamping sleeve is in the non-operative state, for releasing the endoscope by radially returning to expand thereabout.
