Overheating, symptoms inside

[Garlic Breath]

Car: 1995 525iA

I noticed a week or so ago the temp needle was hovering a tick mark above the 12:00 position, it's usually nuts on. I didn't get to drive it though because the damn drive shaft was rubbing against the heat shield due to the tranny mounts were blown out. That’s fixed now and I was driving on the expressway home from the indy going about 70 MPH the coolant temp chimed and I immediately pulled over. I checked the coolant level and it was full and I also cracked the bleed screw and no air came out, just coolant. I was able to cool it down within seconds by turning on the heater. The radiator was hot on the expansion tank side but the other side of the radiator was not very hot.

The radiator is 6 months old along with the thermostat. I swapped out the clutch fan yesterday because it was easy and I had one. The aux fan is operating properly. The water pump, as far as I know, is the original with 71K on the clock.

Diagnosis bad water pump or air still trapped?

Thank you for your consideration.
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Low a behold it is the water pump. I had to get it towed home while my wife went to the dealer to pick up the part. The plastic was complete except that it spun freely on the shaft. Everyone is happy now and I learned a lesson. When you change your radiator and thermostat you may as well change the water pump too!