-
Shoze 15PCS Radiator Funnel Fill Kit Spill Proof Radiator Coolant Filling Funnel Kit Cooling System fill kit for Refilling Coolant No Spill Bleeder https://amzn.eu/d/j7x8n9t
These really help if you don't have one already and don't need to get from Amazon, Sealey will probably do one
-
What car is it? Looked and 6 pot BMW.
Is it a viscous fan on the radiator?
The kits try to remove air by being the highest point in the vehicle cooling system so air gravitates to the highest points (static head¿), but depends on the vehicle.
Does the interior just blow cold? Does it have air con? Does the air con work?
Did you bleed the system after? There could be an air lock and the heater is the highest point