James C. Heidenreich, 60, has been named hospital administrator at Kaiser Permanente Medical Center in Bellflower. He will oversee the fiscal, operational and health service management staff. Heidenreich joined Kaiser in 1980 as administrator at its Harbor City medical center. He has a bachelor's degree from the University of Oregon, a master's from Northwestern University, is a past president of the Hospital Council of Southern California and a life member of the American Hospital Assn. Heidenreich replaces Charles Washington, who resigned in December and moved out of the state. The interim administrator in Bellflower has been Timothy Reed, a former assistant to Washington, who was named administrator of the Kaiser hospital in Harbor City.