Reply to "GTS Clock"

I had exactly the same problem with an NOS GTS clock I bought on eBay.

Keep in mind, these clocks are about 45 years old. Accordingly, the 1970's grease that lubricated the workings when it was manufactured, solidified decades ago. Just send it to a gauge shop to be disassembled, cleaned and lubricated. I recommend either North Hollywood Speedometer & Clock or Palo Alto Speedometer. If you've fried the workings by messing around with it, North Hollywood can install VDO workings. Palo Alto can likely do it as well. There are no external signs of this being done and even the time setting knob still works. It isn't cheap to have this done (about $350, if I recall) but GTS clocks are rare and valuable, so it's worth the expense.