We recently purchased this 2006 XJ8, drove it home 1100 miles. A few days later we found that it was leaking coolant from a broken nipple on top of the expansion tank. Ordered the part and installed it, but the coolant still leaks, now from the bottom connector on the expansion tank. This quick-connect apparently isn't seated properly, but it is difficult to get down to it due to other hoses in the way.

It seems to me that this type of connection ought to have an o-ring. I didn't see one on the old part but there was some plastic goop present. The parts guy at the local (300 miles distant) Jaguar dealer said there was no o-ring with the tank.

QUESTION: Is there supposed to be an o-ring at this point? If so, what size? If not, how does this connection seal and what is causing it to not seal? Is there a workaround for this problem?

Thanks,

Mark--Proud owner of a wife who loves her Jag.

PS Other than this vexing problem the car seems to be in excellent condition.

 

The O ring probably comes with the connector and I am guessing the connector comes with the

hose.The O ring may be missing on your jag.

Scroll to post #20 for pic.

https://www.jaguarforums.com/forum/x...r-leak-110163/

 

We found the o-ring inside the connector. It was covered with some rubberized sealant some well-meaning previous owner or mechanic had used to seal it. I'm suspecting that the sealant was getting in the way of both the o-ring and the metal clip. We got out almost all of it out--a challenge since we did not have means to get down to disconnect the entire hose assembly.
The connection seems to hold water now, but we haven't run the car up to temperature yet and it may still leak steam.

 

Hi Mark


I'm assuming that you mean the lower hose pictured below? There are 2 O-rings inside this end where it connects to the tank. You can't get them separately from Jaguar, you would have to source them locally.





This hose connects to the Auxiliary coolant pump. Only other option would be to replace the hose pictured below. The one the top arrow is pointing.

 

Yes, that is the one. Apparently our efforts to clean out that rubberized sealant worked. It does not seem to leak now. Thanks to all.