BMW Repair: Cooling problem, 1994 bmw 325is, bmw 325is

Question
I have a 1994 bmw 325is. The problem is that it overheats within 3 minutes every time i drive it. I've stopped driving it because I don't want to cause more damage. I've had the radiator flushed, and have had a new water pump and thermostat put in, but no luck. Its been suggested that the coolant is mixing with the oil, but I'm not getting the creamy, light-brown mixture. What could the problem be?

Answer
Aldrich,
 If it's overheating within 3 minutes, there is something SERIOUSLY wrong.  Are you sure you put the thermostat in correctly?  Did you bleed all the air from the system with the bleed screw?  Is the car smoking at all?

 If you have a blown/cracked headgasket, then it could allow oil and coolant to mix in several combinations.  Oil could be getting into the coolant, and vice versa.  Oil floats on water, so look in your coolant tank and if you have any oil floating on top (after the car has been sitting) then that could be a problem.  Same for the oil, check it for coolant.  Like you said, it should have a chocolate milk look to it if it's had coolant mixed in.

 You should probably check with a good repair shop and see if they could fix the problem
 
 hope this helps,
 Josh