Yeah, now its light outside Ive had a look at it.

Tried spinning the fan manually and it was a bit hard/wouldn't free spin when poked with a finger. Seems like it has siezed somehow or the moter's gone. It moves, but i dont recall it being that reluctant to do so. With the coolant not getting cooled it just built up in the resevior before something had to give.

Well, hopeully no permenant damage done. Off to the garage in 10 mins to get a quick once over and go through parts preordered I want for a service before 4th year MOT.

cheers Kev