Today started car had radio and A/C off to hear better, while in park gently raised RPM up to about 3000-3500 max and let it go back to idle.
Could hear a noise not as strong as usual gurgle, but enough to hear when getting RPM higher, then put car in drive and took off, the gurgle sound is more pronounced when moving, maybe the forces of the car moving the coolant back.
Found a video on YouTube where a guy with Dodge truck had similar issue, he even used the same spill free funnel to burp cooling system that I used when putting car together in summer 2019 after all the work.
Next morning he had air again, and then noticed a drop of coolant on heater hose, his flushing tee was near, he pulled cap off and put on Teflon tape and next morning water gurgle was gone, his flushing tee is different looking, might be in Canada as I noticed certain words pronounced differently, or I was thinking maybe Minnesota accent.
Anyways I do have a Prestone flushing tee added to heater hose when I was doing all the work, I never put Teflon tape on the threads, but will try.
There should be a rubber washer under the flush tee cap (like a garden hose washer). I have retightened caps and clamps on these.
I see them as another potential leak opportunity and don't use them. I would rather disconnect a heater hose end than splice in a tee.
Is the thermostat in place? It should be fully closed when cold.
Went and picked up my mom at her place, took her to foot Dr, messed around for 1.5 hours while she was at appointment, went to hardware store, then ate Chinese food.
On way back to her house got caught in huge traffic jam, apparently today or this week is back to school and traffic light were holding everyone up and letting high school kids exit in their cars and buses.
Looked at temp gauge, over half usually under, watched it like a hawk and turned off A/C, made it there, shut off car and major percolating in overflow jug, but none overflowed on driveway.
It's over 110 out, decided to leave it to cool down and drive home in the Corvette, will go back after sunset and check coolant.
Fan was running with A/C off, quick look could not find any coolant leaks, it used to do this all the time when it was girlfriends car, turned out to be tiny leak in water pump, maybe the new water pump is going bad, hope not bought Gates brand to avoid no name Chinese.
In the past 6 weeks or so, this is the 3rd problem I've had with this car, but it almost has 185000 miles.
Went back after dark and saw sign of leakage on thermostat housing, white mineral on the black plastic, of course it could be from checking coolant?
The radiator cap is 2 years old, and one would think that's still not old, the 2 rubber surfaces look kind of worn, so will get new one tomorrow, added coolant and used spill free funnel, made it home without breakdown.
The engine is making a ticking noise now, hope no blown head gasket.
Bought Maddox radiator pressure test kit at Harbor Freight, $124.99 before tax, on PT Cruiser I found no adapter needed just hooked onto thermostat housing, pumped to 15 psi, this tool will go to 30 but don't want to blow anything out or pop something.
Set timer, will check after 15 minutes is up.
Tool doesn't have a way to test radiator cap, but the rubber looks thin, will buy a new cap.
I'm not sure where my tester came from, but mine has an adapter so I can test the cap.
General idea is to only pump it up to around the normal PSI when testing the system.
For the cap, if yours did test it, you can keep pumping and make sure it blows off the extra pressure correctly.
I haven't read every post in this thread, but you can also try parking the vehicle on a slight incline with the passenger side slightly higher, it doesn't take much. But the point is to put the radiator cap at the highest point.
Keep checking the coolant level and topping it off, and it should be up to the bottom of the cap. Keep doing this after several drive cycles and hopefully all of the air will get worked out of the system.
I've had the cooling system serviced a couple of times on my PT and even though the techs bled the system after servicing, when I checked the coolant level it would be low.
In this pic, you can see that the coolant level is below the cross connector to the upper radiator hose. So filling it back up I would have to add enough coolant to completely fill the upper hose and then up to the bottom of the cap.
Since it's raining outside and cool for a change, I put car on driveway, it's usually parked on street and radiator cap is not at the highest part of car, but lower because of the street is higher in center.
Put ramp under passenger wheel, put Lisle spill free funnel back on added extra coolant, ran car until cooling fan came on and shut off.
Now it is at highest part so bubbles can escape, and with the cool weather it should cool down quick compared to 110.