How often to run the engine in a Centurion?

[David Herbert]

Malcolm,
I think your instincts are spot on. If there are no issues like leaking coolant and a vehicle is kept in a dry and reasonably warm environment (ie. not outside in the UK in winter) running it for a short time and not fully warmed up is likely to cause more problems than were there before. I would expect that the relative humidity in your part of the world in winter is very low so there should be no condensation in the cylinders or anywhere else to cause problems. Rings do not just stick spontaneously, there is always a reason, usually either carbon build up or corrosion.

David