@Rendak,
As folks mentioned - these problems with the coolant system are rather legion with the LR4 (at least the AJ 133 engine I have in my 2010)...and coolant problems appear to be multiplying with newer engine designs (for all vehicles).
It seems engine designs are getting more and more complicated and integrated which puts more stress and strain on all these cooling system parts - causing them to fail. Combined with using all kinds of plastic and rubber parts...that makes these things relatively "unreliable" (i.e. they brake, sometimes at the worst possible times) and something to keep our eyes on. As I noted - I have had quite a few troubles with my cooling system but fortunately nothing catastrophic.
Also, making mistakes is all part of "the adventure" and happens to everyone. So if the hose disconnected for whatever reason, know you are not the only, the first, and certainly won't be the last. It happens to the best of us and here is a pretty funny video of Christian and Vera (from their very popular YouTube Channel LR Time) heading into the Alps for a big test drive of Vera's DISCO 3 after a total rebuild (but not total replacement)...only to have the thing almost overheat because Christian screwed up and forgot to close off a coolant hose clamp- which dumped out all the coolant as they were climbing. Pretty funny (as a learning point) and good news because no one was hurt and the engine was fine - they caught the issue in time.
Just to prove that these things happen - we will see you on the high ground!
