Had a chance to work on this yesterday and managed to do what I think is a partial flush of the coolant system. I wasn't able to find a drain plug so I pulled a low hanging radiator hose and drained it that way. The coolant was pretty dirty, but I don't have any reference for exactly what that means... I drained whatever would come out of the hose I popped off, then filled the reservoir with water a few times and let that drain through, then filled the reservoir and started the car. I let it run for a few minutes and then repeated the process. Finally, I put it all back together, filled the reservoir w/coolant and drove home. I stopped to top off the reservoir on the way home.
Unfortunately, the coolant in the reservoir looks pretty dirty again, which is what leads me to believe I was only able to drain part of the coolant in the system and the new coolant I added mixed with whatever was remaining of the old.
A quick question - is the coolant system capable of purging air on its own? One of the things I am uncertain about is that I put the same amount of coolant back into the system that I removed. Beyond keeping an eye on the reservoir and topping it off if it's low, is there anything else I can/should do?
Thanks,
Tom