| Chicago Burlington & Quincy Railroas SD7 315 at Clyde, Illinois on July 22, 1965, Kodachrome by Chuck Zeiler. Built in August 1953 (c/n 18335) on EMD Order 5242, it became BN 6038 and was retired in September 1983. The rectangular item overlapping the second radiator opening is an exhaust stack for a Vapor standby heater. Most of the CB&Q GP7, GP9, SD7, and SD9 series diesels had these standby heaters installed. The purpose was to allow the prime mover to be shut down in cold weather, and the standby heater would be turned on and heat and circulate the cooling water to prevent freezing. In practice, the prime mover was usually left idling because of the difficulty restarting it with cold batteries. |