If it's not storing it then the battery may be
dead. 
  The VLCs (and, I think, all the VAXstation-4000s) use a DS1287 RTC chip
with an onboard Lithium battery.  Just like a real Pee-Cee :-)
  According to Dallas, they have a rated battery life of 10 years, but I
haven't seen any in my VAXes go dead yet.
  If that's really the problem with yours, then I have some DS12887As if you
need one.  They're supposed to be backward compatible with the DS1287 which,
AFAIK, isn't made anymore.
Bob