It’s certainly a good start. When I did my alternator there was a huge airlock that took a long time to work through, until eventually the expansion tank started to fill but the amount of air the came out was ridiculous. I bled mine until the cooling fluid started to bubble out through the bleed valve and all was ok, no leaks to speak of.  Got - 2017 SDV8 Autobiography in Loire Blue
Had- 2008 TDV8 Vogue SE in Java black
Had - 2007 S/C in Stornoway Grey