The engine of our BMw 850i is getting hot.
We've replaced the radiator last year, so that can't be it.
When we start the engine and drive, the fan on the back of the engine (there are two fans, one on the front and one at the back...) starts to rotate, but the one at the front doesn't. Is this O.K and is this NORMAL?
With the fan at the front I mean the one that is hidden and that you normally can't see. THIS ONE IS NOT ROTATING.
PLEASE HELP US 
