overheating mystery...

[Titan 3]

I need some quick help, from you guys please...

I pulled the radiator and clutch fan, to access the condenser.  (In the middle of an AC rebuild)
The coolant drained clean.  The previous owner was using something other than BMW coolant (green in color)  When I buttoned everything back up, the needle just kept climbing.  I opened the heater core during the fill, so there shouldn't be air in the system.  Any thoughts on what might be causing the overheat?

Thanks guys!

[Wizard]

http://www.esatclear.ie/~bpurcell/318ismaintenance.html#bleed

DO NOT OVERTIGHTEN the bleeder screw...Most are black plastic and will break/strip..

[Titan 3]

I hadn't bled it well enough.  Good as new now.  Thanks for the help tho!