Just brought a good head as the old head was to far gone to be welded i hope this cure it i will keep you posted
Got to ask. How 'good' is 'good'?
If it was second hand then I'd be asking the seller some awkward questions.
OTHERWISE
The rad has got a central baffle and is not sludged up at the bottom and externally clean allowing a good air flow.
The air con (if fitted) rad is externally clean, again allowing good air flow.
The viscous fan is operating correctly.
The water pump is operating and hasn't fallen apart
The drive belt tensioner, and belt, are in good nick and doing their jobs so that the water pump is actually pumping.
The stat is operating correctly. You can run this engine without one. It will run cold but it proves the point.
The trickle pipe back to the tank is clear.
If you're confident of all of those then my money is on the head.