Help 99 323i overheating

I need help quick! I have a 99 323i on my way down to San Antonio I had a problem. My water tank busted. I bought a new water tank new hoses and a new termestat. My car is over heating. The fan clutch seems like it is not working. Is there a sensor that tells the fan clutch to kick in. I am able to stop the fan while the engine is running. Also the bottom water hose is cool and the top one is hot. Dose any one have any information for me. I am still in S.A. and I need to get back to Dallas Tx. soon. Help.

I have taken the water pump off and it looks like it is fine. I need help.

Check the relay of the fan, I have an experience to make the tank damaged before at an Japanese car.
If the relay was damaged, the fan did not work, the engine will over-heat and make the tank brust.