Recently had a leaking coolant expansion tank that I replaced and refilled. Since then I've noticed that my the engine cools down, the large hose that runs from the waterpump to the top right of the radiator collapses.
Maybe hard to tell from the pic but the left side of the larger horizontal hose right before it splits and then connects to the waterpump is almost completely sucked in and flat.
Part #1 (the larger section) here:
https://www.realoem.com/bmw/enUS/sho...diagId=17_0295.
No overheating issues to date. Just curious if this is normal or something I show be concerned about?