Hi guys , we’ll ive sorted prob with top hose collapsing , i tried.a new radiator cap and it didn’t really help , so then on inspecting a few of the other pipes I found the small one from rad to expansion tank was solid on the bottom elbow , cleaned it out sorted no more top hose collapsing😁, .i have a question , at what temp should the fans come on, I’ve noticed that they come on when I turn ignition key to just off the start position on ignition switch or momentarily when I switch engine off ,but I never here them running even after a motorway trip and then sitting in traffic , any ideas