Jackson 6700S Railroad Tamper Heavy Equipment. The following are known specs of the tamper. 1992 model Jackson 6700S. 8.3 Cummins Turbo Diesel. Harsco serial number 151883. Union Pacific number ATS 9213. Computer system unknown capability. Runs moves and vibrates tamping heads. Comes with light buggy not shown in pictures or video. Unit needs some work to lift & line.