[heero_yuy]

Well done Snoopz.

I need a new part but have sussed why the fridge wasn't running properly:

I cleaned up the starting relay in case the contacts were faulty and temporarily shorted out the thermal cut out but it still only ran for about 5 minutes before stopping. So that ruled out compressor problems.

The last thing was to bridge the thermostat contacts and YAY! it runs.

I'll probably have to get some kind of generic part as the unit is over 35 years old so an original is likely to be unobtainable.

I think this has been developing over a long time as I thought on the odd occasion that it didn't seem very cold inside.

I'll rig a temporary manual switch. I do have a spare digital temperature controller so I might configure that as a thermostat.

More money saved.