I would make absolute certain that you have a water pump that is designed to turn in the correct rotation. Wouldn't be the first time a parts place has sold the wrong pump, or a pump was mis-boxed, for the application. Cars with serpentine belts have pumps that spin in the opposite direction from ones with V belt setups.....the pumps will bolt right up, and look the same, but the impeller is different on the two styles.
I don't think you have an air in the coolant issue...I think you have a water pump issue. A normal, working cooling system on these cars will burp the air out on it's own after heating up and cooling down.
as others have suggested, I would also remove the thermostat(cold engine, of course), start the car, and see if you have full coolant flow instantly. If you do not, or if the coolant surges out of the radiator instantly, I'd have to bet on it being the incorrect water pump. If however, you DO see proper coolant flow with the t-stat out, it's probably a bad t-stat...new or not. hth
|UPDATED|3/2/2019 7:26:38 PM (AZT)|/UPDATED|
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Joel Adams
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