Bob, my opinion for what it is worth is that you are losing the battle and impressed that you reached 49k! I think the rad is made from glass filled nylon. That’s only good to around 110C before it loses its mechanical strength. The coolant exiting the cylinder head can reach that temp in my car. So perhaps when you tighten it, any tension is lost as the outlet deforms a little more when it next see’s very hot coolant. I thought about making up an internal ali anti-crush ring to go inside the outlet in mine so that I had something solid to tighten the hose clip against. I never did, in the end I bought one of those nice rads form Mr H.
![[Linked Image]](https://dl.dropboxusercontent.com/s/hyy4ubwi3dwqzrk/rad1.jpg)
Not mine but one that failed from another member
