Coolant isn't bleed till the system is running and all air is removed by the bubbles of the Coolant Circulating IN the system and it comes up to operating temperature
I think I’m having g this issue on my Jeep,trying to figure out where my leak is . I’ve notice,some fluid right under neath on the side of where the thermostat is but I don’t see it leaking when vehicle is on . I hope this is my problem