A few years back I blew the head on an overheat. Apparently it had been running hot for a long time but my gauges only work intermittently so I'm used to ignoring them. Today I went to a shop not a half mile from home. It had a spot of water under it that looked like the overflow hose had released some from the overflow canister. Its not full its just below the full line.
From there after it sat for two hours I drove maybe 5 miles when I got home it seemed very warm so I lifted the release latch on the rad cap and the overflow tank started to boil. I do not think it should be this hot for that short of a drive especially since was cool out.
I have a new radiator, a new shroud the fan is always moving whenever I lift the hood with it running, the thermostat is whatever NAPA gave me, I even replaced the heater core with one that had a working valve when I did the head and it worked fine. I also recently replaced the cap that plugs the water choke branch.
The only suspect thing I have is that when I open the cap and run it until the thermostat opens. Then if I rev it up the level of coolant drops to the top of the fins and if I have a funnel there it will rise up and let loose bubbles in the rising liquid when I let the revs drop. No matter how many times I do this I get bubbles. Am I just not getting all the air out or is air being sucked in somewhere?