In the engine bay the bottom hose was fairly warm......top hose that goes to the Thermostat was cold. I saw another little looking bleed screw that lives very close to the bulk head, I undid this and coolant came out with no troubles.
The only time I managed to get any air out of the blue screw on the Thermostat housing was earlier when the temp was showing 70 and this took me a 5 minuets of keeping the revs at 3,500-4000. Then when I started pushing the hoses listening to the air escaping all was good but the engine was at idle which then it went back down to blue, this only took a few minutes. Really don't know what is wrong or what to do?
ps...... I replaced the thermostat earlier

Any help would be great.