Well, this might put me over the top again!! I've replaced the octopus hose, expansion tank, several other hoses, thermostat housing, thermostat and for a while, I hadn't noticed the smell. Since I got it back from painters and detainers, I was noticing what I thought was a urine smell when the car would shift from recirculating interior air to exterior air, but today I noticed a coolant smell outside and on the way home the low coolant light came on first time ever.
I'm going to let it cool down and check the level.
What could be left to check??????
And what are the worst case situations?

 

Phil,
While each time my low coolant warning light goes on, my heart skips a beat, I know from experience that it usually means I am about 1 cup of coolant low. The sensor is located so close to the base of the filler neck that in my car if I am low by a cup or so it will trigger the warning. I, too, have done all of the hose-clamp-overflow reservoir-heater-octopus hose replacements, and yet I still on occasion smell the sweet burning smell of anti freeze. You might check the radiator itself. Fill it up and see how long it takes you to get the warning light to come back on. That will give you an idea of how severe the leak really is.

 

Well, I just checked and it was almost empty, the expansion tank. I just had the last hose changed about two months ago, maybe three. So I know he filled it then. So I'm thinking that's a lot to lose in that time and see no signs of a leak. Only a smell.

 

That is a lot of coolant to lose without seeing it on the ground. I would suggest a pressure test to locate leak before you find yourself in some trouble.

 

It might have had an air pocket, but you said it had been 2 months, so I doubt that was your problem. Air would have worked itself out by then.

These cars like to leak slowly and the engine is so packed in there that leaks often hit things hot enough to evaporate coolant before it hits the ground. Fill the expansion tank and check it every day. If it still goes down, then tberg's suggestion of a pressure test is the way to go. AutoZone will loan you one, just make sure they have the right cap for the Jags.

You might also check the overflow tank in the fender well. It should only have a small amount of coolant in it. Sometimes too much gets in there and it doesn't flow back properly.

 

I had an occasional strong smell of coolant on my 2001 XK8 with a drop in Expansion Tank level but could never find a leak.

It turned out to be a minute crack in the base of the Expansion Tank. Sometimes this would open up and allow coolant to dip onto the hot exhaust manifold where it would immediately flash off giving the smell but no apparent source of the leak. The problem was that it didn't do it all the time.

Graham

 

I've already replaced the expansion tank within last 4 months. The strongest smell seems to be concentrated in the rear of the engine area where we've replaced the octopus hose and others. My optimism is fading fast.

 

Lots of coolant carrying stuff back there, including heater pump, heater valve, throttle body and all their associated hoses. I second the pressure test suggestion. Note that the small hose just below the coolant tank fill cap may need to be pinched shut with most pressure testers for the test to work properly.

 

Mine was leaking from the heater hose return under the fuel injector housing. Sounds like the same area on yours. If you can't borrow a pressure tester, this is the one I used. Its the green cap for your car. Piece of mind for $80 Radiator Pressure Tester Kit

 

you can borrow one from autozone

 

Hi Phil, I just had a leak in my wife's XJ8. very small drips on the garage floor but lost a lot of coolant while driving, it turned out to be and the thermostat and the housing connecting to the engine.

They did a pressure test to find the leak, had to remove the manifold to get to thermostat and replace the whole housing and thermostat, housing had crack, when heated up it would leak when hot and driving, the garage floor drips were mostly just leftover coolant dripping .(I assume the XKR has somewhat similar thermostat and housing.) Viola, no more leaks!
Good Luck and

Happy Motoring...

 

I have a similar thing on the wife's XK8 vert, it's a valley pipe, you loose the water in the valley, the heat from the engine evaporates most of it before it even hits the floor if it's slow enough, did a pressure check and you can hear it leaking out, I will add the ally thermo tower whilst I am at it......... Throttle off and the manifold out, no point mucking about

 

My money is on valley pipes if you,ve not done them already. Plenty of hoses down there, do them all while you have the car in bits

 

So, what's the procedure to get to them? I'm assuming a BIG job.

 

Phil, yes it's a pretty fair job. I attached the procedure from "jaguar@blackonyx.net" (its a x308 but should be very similar) I would do a pressure check before attempting this job. It's on my list of winter projects.

 

Step 1: Remove wallet from pants...

 

Damn, and here I was thinking yeah, I'll just put a bead of silicone on the side of that expansion tank and it will take care of the anti-freeze I see seeping out of it.

I'm having a tough enough time finding a new expansion tank for a 2003 XKR or I'd swap it out. I don't even want to think of replacing all the hoses too but I probably should....

 

Well, I think I've got it somewhat located, not the exact hose or issue, but its definitely coming from under the throttle body area. I actually let it sit about 30 minutes in the garage with the top open and when I did a very technical sniff test, it is definitely rising up from that area. Not to the right or left but directly underneath. I still see no visible weeping. I'll check tank in the am to see if its lower.
In the immortal words of Han Solo, "I've got a bad feeling about this!"

 

I'm seriously getting beat down by this issue. And a small oil leak in the front of the engine. I'd like to think its the oil cooler hoses. I don't plan to put infinite money in this car so I hope I can get this coolant issue cleared up. I swear, if I can't find it, I'm putting in a can of radiator leak stop!!!!!!!!!!
I had a similar issue with a 2003 x type and it worked!!!!

 

Don't do it! There are several check valves in this system and leak stop can cause them to malfunction. This is not your father's Olds.


There are two coolant hoses that go to the throttle body and further down (out of sight) is the coolant pump.


After all you have invested, it is not time to risk your engine rather than do a relatively simple repair.