Neon clock loses time even after replacing clockwork and batteries.?

Question

It works for short time, then slows down for some reason. The neon part is plugged in but the clock is battery operated. I am wondering if the neon light has something to do with it losing time? How I don't know but maybe someone can shed some light on the subject. Here is what the clock sort of looks like.
http://www.neon-signage.com/catalog/translucent_blue_neon_clock_2667754.htm

Answer 1

Is there an adjustment for the clock on the back? Either that or the battery is not making good connection, there is dirt in the clock. good luck