I've been chasing a coolant leak since the day I bought my car!! We've changed the tstat housing, expansion tank, octopus hose, and several other hoses as well. Changed most of the old clamps to new style, and I STILL have a coolant smell! Greatly reduced but still there and when i have top down, its there when i stop at lights and such. My mechanic has checked everything, looked everywhere and we can find no trace of leaks. It seems to be mostly coming from the drivers side area and we did find an expansion tank weeping at the hose clamp. hence the new tank.
Where oh where do we look now???? There's no noticeable loss in the tank so I'm out of ideas. And it's had time to burn off any residue from repairs and my mechanic is really good about cleaning any spills anyway.
Sme guys here have said they just live with it but it drives me CRAZY!!

 

There are actually two tanks. There is an expansion tank hidden in the fender and the fill tank that is visible under the hood. Which did he change out?

 

I really know less than anybody about these cars BUT When I had the Jag dealer do my pre purchase inspection I mentioned antifreeze smell, he called me back and said they found no leaks. I asked him to do a pressure test and he found the following, found seep from bleed pipe at resivior. replace 2 snap clamps with screw clamps. retest an all aok. I didn't know there were two tanks so I am not sure which one they took care of.

 

I wouldn't ignore a coolant smell either, small leaks tend to get bigger over time and major problems can be the result. The best way to find a leak is with a coolant pressure tester. I found a hidden leak with this one: Radiator Pressure Tester Kit. if you buy it, it is the green cap for an XK8. Just park your car in a quiet place pump it up to 15psi and listen. Mine was a heater hose under the fuel injector manifold. By the way your car looks great.

 

I had a tiny leak from one of the heater pump hoses after I repaired the pump, I couldn't face taking it all out again so put in some "rad-weld", which fixed the drip.

 

There's the Expansion Tank (item 1) in the engine compartment and the Atmospheric Recovery Bottle (item 11) in the front wing behind the wing liner:



(click on the image to enlarge it)

As the engine heats up, the coolant expands and excess flows from the Expansion Tank to the Atmospheric Recovery Bottle.

After the engine is switched off and cools down, coolant contracts in the Expansion Tank and it is drawn back from the Recovery Bottle to keep the Tank to the correct level.

Graham

 

the small one up top. We checked front behind the bumper nose and found no leaks.

 

If you mean the hose that snakes from the front radiator to the fire wall area, we did that too.
Thanks! I'm loving the color.

 

The only major leaks we found were at the Tstat housing manifold. That notorious plastic pipe. While I changed that, I ordered the metal housing as well.all the other places I found were very faint weeps due to clamps. I had to replace the octopus hose due to that darn norma coupling leaking. Again a faint occasional bubble.
He's got it in today to do the "sealed for death" trans. I'm getting a strange buzz sound when it's shifting in the first couple gears. Very annoying so starting with the new fluid and filter, etc.
I'm having him do another preasure test while he has it.

 

Phil,

The bottle behind the bumper is the Screen Wash Reservoir.

Atmospheric Recovery Bottle is at the rear end of the front wing.



Graham

 

the hose I was referring to runs from under the thermostat housing back. Its under the intake manifold and impossible to get to unless the manifold is removed. it's a common leak and hard to find because the coolant leaks out on top of the motor and burns off. Or it drips on to the catalytic converter. if your mechanic removes the plastic engine covers while doing the pressure test he should see it that's the problem. Mine lost about a cup of coolant a month but the smell drove me nuts. I've ordered the parts and am going to tackle the job in a couple weeks.

 

I should have known that! We had the entire front off, fenders and nose.
! He checked that recovery bottle too.
He says its hard to do a pressure test due to the expansion tank. Does that sound right?

 

No that doesn't. He must have the wrong adapter.

 

We found the leak. I can't believe my new metal thermostat housing has a damn leak!! Bad seal. It's only a few months old. Not a bad leak but enough!!

 

Where's it leaking from?

I had to send one back with a badly machined thread for the cap which wouldn't seal properly but have done three since then with no problems.

Graham

 

Where did you get that aluminum housing? Others would probably like to know.

 

It was from British Parts UK.

They immediately dispatched another without even waiting to receive my faulty one back and refunded both the cost of returning it and the original P&P charge.

Now that's customer service!

Graham

 

Exactly the same place. The cap.
Problem is, it's so long ago, I don't remember where I got it!!

 

The housing I bought from Welsh Ent. was very good quality. I haven't read any complaints relating to that source.

 

I think mine came from somewhere in Florida. Is there a well known parts supplier there? I'm sure a forum member hooked me up.