I had a slow coolant leak that I have had trouble finding. I finally found it leaking where a coolant hose connects to the underside of the AJ810343 Outlet Pipe. On the XJR this is the cast aluminum K shaped pipe connecting to both cylinder heads. The hose connects with a wire clip and the hose is actually sealed with an O-Ring.

I have included a close up of that connection. A second photo shows the basic location standing at the front and facing toward the rear of the car. The hose connection is seen to the right of the coolant header tank and to the left of the air inlet scoop.

I looked at the JEPC but could not find this hose or the O-Ring. Anyone know the part number for the hose or the O-Ring?

I have not found where the other end of the hose connects either.

 

I had the exact same issue with my 2006 XJR finally ended up buying a $.90 O ring from my local ACE hardware store it is a Danco 1.25 inside diameter and 1.5 outside diameter O ring. so far works fine.