You sir i think have solved the problem!!!

Went out this morning,had it running for an hour while i polished it,then took it for a blast round the streets,kept it running while i was doing other stuff then took it for a couple more blasts round the block. To my relief NO over heating!!! I Have noticed now the fan comes on around every 60 seconds for a about a minute or two,before the fan didn't come on at all.

So fingers crossed the problem has been solved! The car has been a real pain.Got it off BCA website for £1,300,owed us £1,600 with fees & delivery from Newcastle.Had a bit of work done on it & rear quarter sprayed because of rust round petrol cap so before the work on the engine it owed us around £1,900.Now we've had head gasket,head skimmed,oil pump,thermostat,radiator & now heater valve,prob another £400 that makes car owing us £2,300 & we're only selling it for £2,175!!! What a nightmare,wish I'd posted on here sooner!!!