Proper bleeding procedure

[EUROPEANLOVER]

Hello everybody. I've been away from this site for quite some time now. Actually I read the posts but haven't posted anything. Anyway, my vehicle is a 2003 BMW X5 3.0 (E53, M54). It now has 182,000 miles. I am a GM technician for over 20 years and do 95% of my own work on the Bimmer. Just yesterday I replaced the waterpump with a metal impeller one, thermostat, ac and waterpump belts, upper and lower hoses with new coolant sensor and oring in lower hose. Drained radiator via drain plug at bottom right of radiator. Rest of coolant came out via removal of waterpump and lower hose. Didn't seem much coolant came out. ??????? Anyway, bled cooling system by pouring (BMW) coolant in expansion tank with bleeder screw removed. Poured until I got a steady stream out of bleeder screw. Closed bleeder screw. Ran vehicle with cap off to make sure no air pockets and opened bleeder screw one more time to make sure I still have a steady stream. Yes. Let vehicle run for 15-20 minutes. Temp gauge in the middle at 12 and plenty of heat. But upper radiator hose is hot and bottom hose is cold. ???????. Let vehicle sit for 2 hours with a fan on engine to cool down rapidly. Checked coolant level again. Topped off with water and coolant. Let vehicle run again. Temp gauge in middle and plenty of heat. Drove 40 miles from work to home. Excellent heat and no overheating. Temp gauge stays in middle. But lower radiator hose is cold to the bone. What gives????? Is there something I'm overlooking??????. Is this normal on this engine???? Please help...... Any advice would be greatly appreciated. BTW, changing the waterpump resolved an issue with a mysterious rumble on slight throttle application that I've been having for the past 2 years. Yeah!!!!! One INDY SHOP and BMW fanatic told me it was a motor mount and possibly the Vanos Unit. Lol.... Anyway back to the lower hose being cold. Please help.