Abstract: A seal construction is provided for sealing a rotating pump shaft against passage of a fluid along its central axis. The seal construction includes front and rear sealing flanges mounted coaxially to and rotatable with the pump shaft. A temperature stabilized chamber is provided adjacent each sealing flange including means for recirculating and cooling fluid disposed therein so as to maintain the fluid between adjacent engaging members at a substantially constant temperature thereby maintaining a flatness of the sealing engagement between the sealing flange surfaces and the engaging members.