Honestly, no I'm not sure. I just put the fans in because the originals were broke. And because the fan is electric, I'm not too terribly sure that I'll hear it. I may try to flush the whole system this weekend.
I can't say 100% that there are no air pockets, however I ran the car for 30 minutes with the heater on full blast and fthe filler cap off. I revved the car up a few times after that, when it stopped bubbling while revving, I figured I was good to go.
The problem seems to be worst in stop and go traffic, oh and worse than that, if I turn off the car for 15-20 minutes then turn it back on, it gets hotter.
Thanks guys.