Symptoms of air in coolant?
Take the t-stat housing off and remove the t-stat from the housing....then put the housing back on, just snug it back on with one bolt. Leave the radiator cap off so no pressure builds up and start the engine. Keep filling up the radiator till its topped off. When it won't take anymore water/coolant......it is 100% full and you have zero air in the system.
Turn on the heat and see if blows hot...it should because there's no air in there anymore.
Now you can be sure the system is fine and that you probably did have some air in there somewhere.
Now put the t-stat back in and tighten it down with both bolts. Of course you will lose some water/coolant by putting the t-stat back in......... Top off the coolant, Start it back up and let it idle till you see the coolant start to flow in the radiator cap. When the level drops...IMMEDIATELY start topping it off. Wait one more time for the t-stat to open again and you see the flow....then top off again if the level drops. If the level did drop down again.....do it a third time.....and so on....till the level stays full as coolant starts flow.
Done. Put the cap on and go.
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