2004 Mini Cooper S overheating
My 2004 Mini Cooper S is overheating and I don't know why? I turn on the the car and let it Idle. After 10 min the overflow tank starts to boil making a popping sound. The temp guage starts to rise and I shut it off. I changed the thermostat didn't work. Took the head off and the gasket looked new. I had the head checked and it was milled and didn't have any cracks. The head got the OK from the head shop. So I put it on, and it still did the same thing. There is no water in the oil and nothing coming out the tail pipe. There is no leaks at the water pump. I checked the radiator next and its OK. What can be causing it to overheat?