Good morning Bob, I thought I'd replied to this on my phone so if this comes twice my apologies.
The fan will switch on at different indicated temperatures depending on the engine load so when idling it'll be about 103, when on the road it seems to be about 100 but yesterday the indicated temperature once thoroughly warmed up was 100 at 50mph and it never used to run that hot at such a low speed.
It's a 1.8 black top Zetec.
I will try and see if there's any air in the system first and then check the thermostat I think. i've also ordered a non contact thermometer so I can check temperatures around the system.
The "cooling temperature" thread is interesting and will give me some comparisons.
