hi yall im new to the hummers world,
i had to replace the thermostat on my 07 a couple months back cause it was stock open, replacement went smooth with no problems, but then yesterday i had to replace my water pump cause the shaft had a lot of play, did the replacement and when i turned on the car after i let it run for a while i noticed it started overheating, turned it off started checking for coolant leaks and fluid levels, everything checked out OK, tuned it back ON and the tem needle passed the 3/4s again so i turned my HEATER on to see if i had any but i did not have any heater as the car was idling, then i thought i could be the THERMOSTAT again but then when i took it for a road test as the RPM started to raise the heated started to work i would say i little hotter than usual and the TEMP needle started go go back down but as soon as the engine revs slowed down or i got to a stop the TEMP will raise again...
i think theres an air pocket trap in the system but isnt this system supposed to bleed itself?
does anybody how how to bleed the system?
any other thought what the problem might be?
any help is greatly appreciated it!!:

 

When I replaced the radiator in my '06, all I had to do was squeeze the driver's side radiator hose a few times to pump down the new anti-freeze in the coolant tank.

The next day I did have to top-off the coolant tank with a bit more fluid but that was it.

 

thanks!!
it worked! i just wanted to make sure theres not an specific procedure or bleeding valve but the traditional way worked just fine