Abstract: The method involves injecting into the hollow member adjacent its upper end a body of the material for coating the interior of the member, and then forcing the body of coating material downwardly while forcing an annular portion of the material laterally outwardly into engagement with the walls of the hollow member. This is done by a brush having bristles facing outwardly and of sufficient flexibility to enable them to pass through a stricture of a predetermined degree in the hollow member and to expand when not in such strictures so that at all times the bristles are in close proximity to the inner surface of the hollow member and spread the coating material therealong, pushing the extra coating material ahead to subsequently coat lower portions of the interior of the hollow member.