hai you can see the small screw at water pipe location right side same location for termostat other car don't have this screw ....how to remove the bubble ......open this screw but not remove it ....radiator cap must be lock and water tank must full after that start your engine the water must flow normal coming out from this hole if you see bubble coming out wait until it disappear make sure that the screw not jump out because you need to tight it back in engine running condition monitor your spare tank make sure it have water.......how long engine need to run?...........until your fan running in high speed..2 or 3x......make sure you monitor temp. also..... after that if you see there is no more bubble and water coming normally at the screw hole tight it back and refill back your spare tank ............start your engine again until 2 or 3x fan running at high speed and monitor your temp. if temp stable mean your problem already solve.WARNING please not open your radiator cap you can open it when engine and water is cold......thank