The inside upper hose nipple on the coolant expansion tank broke on my '05 X-Type Wagon, letting coolant spray around the engine compartment. The hose appeared to be in place against the tank and until I touched it I didn't see the problem. My first symptom was that the heater was blowing cold air. I didn't see any low-coolant light and the temp gauge was right in the middle. I have ordered a new tank and it appears that replacing it is pretty simple and straight forward. I also understand that I should use a Dex-Cool type anti-freeze and am not sure how vital it is that the jug has 'Jaguar' printed on the label.

I am concerned that the coolant level indicator didn't come on. Is there a good way to test the sensor while I am replacing the tank? Can I trust the gauge and believe that the engine didn't get overheated?

This appears to be a fairly common problem. I have only had the car for a few months and any advice would be welcome.

-Jim

 

Off topic, but I'd suggest you to open the hood at least once a week to check fluid levels.

 

Well when my expansion tank went out, it really let me know... It spewed coolant everywhere and smoked as soon as I stopped. For me, I noticed that the temp gauge was going a small bit above the middle (where is normally stays) so I opened the hood to check it out. As nardoswiss says, coolant levels should be checked every two weeks if you want your car to keep running, but in this case, I had just inspected my car about three days before the incident. When my tank went out, I didn't get any warning other than I noticed a small change in my temperature which made me pull over and check over my vehicle. If your in-cabin temp sensor didn't indicate you were overheating, you probably didn't.

One small note, when you're installing a new coolant expansion tank, make sure the clip connector on the side that failed is facing downwards. For instance, you don't want for the clip to be able to get caught/pushed on by the headliner so you just twist it around. It has been speculated that this clip facing upwards and the natural decay of plastic is the whole reason these tanks fail in the first place.

 

I just replaced my tank ($100 from PartsGeek) after the second small nipple broke. I had fixed one by putting a threaded brass plumbing nipple through the tank sealed by JB weld. The second was a temporaty fix with a length of SS brake line also sealed with JB. Probably would have last forever but I was afraid the Brake line would eventually rust.