First thing I would do is check the T bleeder valve and make sure it has been replaced with a metal one vs the plastic factory one that literally deteriorates over time and falls apart, spraying coolant everywhere and leaving one stranded on the side of the road. Just search online for "LR3 T bleeder valve" and you will see what I mean.

 

Looked it up on Amazon, still made in plastic though. I have one with no bleeder, just a straight ****** line insert, made in brass that I will use to replace the stock one.

 

It took me a while to find the link (I posted it in another LR forum years ago), but this is the one I bought. At first, I went to Home Depot and bought some riveted brass cone pieces and screwed them together, but they ended up being too large and I stretched the coolant hose while putting it on. Cut the stretched part off, then ordered this: Upgrade for silly plastic T fitting in hose for Land Rover LR3

Being so frustrated that LR would make such a cheap part, I didn't care how much it cost. Given how much everything else costs with the LRs (like a $350 side view mirror... ENCLOSURE ONLY, MIRROR NOT INCLUDED), this seemed cheap enough to me.