A covered cable assembly includes a cable and a sealing assembly. The cable includes a metal sheath and a cable core. The metal sheath has a sheath terminal edge defining a sheath opening. The cable core extends through the metal sheath. The cable core includes an electrical conductor and an oil-impregnated paper insulation layer surrounding the electrical conductor. An extended cable core section of the cable core extends through the sheath opening and beyond the sheath terminal edge. The sealing assembly includes an oil barrier tube, a sealing mastic and a pressure retention tape. The oil barrier tube surrounds the extended cable core section. The sealing mastic surrounds the cable about the sheath terminal edge and overlaps portions of the metal sheath and the oil barrier tube adjacent the sheath terminal edge to effect an oil barrier seal between the metal sheath and the cable core at the sheath opening. The pressure retention tape surrounds the sealing mastic to limit displacement of the sealing mastic.