I'm wondering if you filled it properly. When I do my coolant, after flushing and all that crap, first I fill the LIM as far as I can, then install the tstat and put the housing on. I then fill as much as I can in the radiator, and start the car up. I let it run a while, tstat opens, bleed air, coolant goes down, and I keep topping off until it won't take any more. Put the rad cap back on, make sure the reservoir is at the proper level, and done.
You did let the car run and get up to temp, then top it off before calling it good, right? Don't go by the reservoir, you check the coolant level by removing the rad cap (not hot, obviously).
