Coolant leaking from under hood 735i "89

[Demmy]

I just replaced my Radiator due to a leak. I forgot to loose the bleeder screw before I fill the reservior with the new coolant, and when I got the screw opened to get the air out and top the reservior , I started the car to let the coolant flow, then there was an overheat after the car run for sometime with coolant leaking from under hood by the engine. I really cannot tell where that coming from. I need help, please.

Secondly, where do I start with the tune up for my 735i "89. I already got the parts needed? Please help.

[shogun]

probably there is still air in the system. The engine has to come to operating temperature till the thermostat opens, then the liquid will circle in the large cooling cycle, before only the small one internally in the engine. When the engine is warmed up, set both sides of the heater system to hot and then also the heater core is bleeding.

The leak might be from the overflow hose, that is normal when bleeding and it means you still have air inside the system.
http://www.nmia.com/~dgnrg/page_19.htm

[Demmy]

Thank you very much for your help. I did exactly what you mentioned, besides the plug in between the temp sensor ( I didn't replace it) I used the same one. It's not leaking anymore. Thank you. I just need to start working on the tune up now.