[OBC John]

Yes, a possibility.
Just occurred to me though, that the undertray is going to catch any drips and if it's not enough to run off, it will just dry there. So, off with the undertray I suppose.

 

[OBC John]

Any crusts around the filler cap?

No. Clean as a whistle.

Heater matrix?

Any dampness under the dash?

No, nothing. And no dodgy, damp smells.

 

[OBC John]

Well, topped up the coolant again yesterday (2 litres up to the "Max" mark!!). Still can't see anything under the car, either at work or on my drive. Of course, you can't see much gazing under the bonnet even with a torch and telescopic inspection mirror so I'll drop off the under tray over the weekend.

Sent from my Nexus 10 and a Black XF-S 😎

 

[OBC John]

Pretty sure it's not internal. Oil looks fine and I'm sure there'd be steam when I opened the oil filler cap.
Gave it some beans on the motorway today and certainly there's no drop in performance.
No funny smells in the cabin.
Undertray coming off tomorrow.

Sent from my Nexus 10 and a Black XF-S 😎

 

[OBC John]

Exhaust is clear.
I could do with a pair of ramps if anyone in the Birmingham/Black Country area has a some and would be willing to lend them.

Sent from my Nexus 10 and a Black XF-S 😎

 

[OBC John]

Thanks Allan. I'll try the "follow me".
I've had my head under the bonnet with the engine running after a run. Can't hear anything (sizzling) or perhaps more telling, smell anything unusual (like water evaporating).
The plot thickens! 😞

Sent from my Nexus 10 and a Black XF-S 😎

 

[OBC John]

That's a lot of water to lose in such a short time John

I know, Dave. Hence the thread title. It's a mystery. And to add to it, I've done a few miles today on the motorway and the coolant level doesn't appear to have dropped. What T. F.? 😕 (Of course, now I've said that, I'll get the warning as soon as I start, tomorrow morning! 😨 )

Sent from my Nexus 10 and a Black XF-S 😎

 

[OBC John]

A conclusion I've been heading towards. Been for a walk over at Tenbury Wells this morning, a round trip of about 60 miles and no warning (have to admit to not actually having looked in the reservoir as yet today). But counting no chickens yet.

Sent from my Nexus 10 and a Black XF-S 😎

 

[OBC John]

Has it had a coolant change recently?

Not that I know of. Last time it was out of my sight was for the transmission oil change. Can't think why they'd drain the cooling system for that. So I see where you're going. Where would an air lock come from unless it's been in there since last service.


Sent from my Nexus 10 and a Black XF-S 😎

 

[OBC John]

I still haven't been able to identify where the coolant is going and so, as the next service is due, I've booked the car into Stratstone next week and they will investigate while doing the service.
I'm still convinced it's not a head gasket. There's no evidence (oil is fine, performance unaffected, exhaust clear (if the gasket had blown between a cooling channel and a cylinder, surely the cooling circuit would be pressurised by the rising piston and blow hoses off?)). I think it's either a hose dripping onto the under-tray and running off when I'm driving or else a hole in the radiator doing the same and also evaporating. Let's see. I'll keep you posted.

 

[OBC John]

Good luck John, water / coolant issues can be maddening and means that any journey becomes a gamble as to reaching your destination in your car or a taxi.

Thanks Nathan. It's not quite that bad yet. And I have 5-litre container of coolant in the boot just in case.

You're not using one of those comedy glasses to pour the coolant in are you John, those ones from the 90's where the liquid stays in the glass?

I was beginning to think that. Thinking that maybe there's an emergency, back-up, overflow coolant reservoir somewhere and I'm just filling that up.

 

[OBC John]

Car went in to Stratstone this morning for a service and investigation as to where me coolant is goin'. Call at lunchtime to say service is done (with some recommendations which I'll perhaps start another post about . . ). Anyway, they say they have seen the leaking coolant but can't see where it's coming from without starting to strip stuff. Do I want them to go ahead? So that's what they're doing and I'm waiting for the call to tell me how much all this has cost me.

 

[OBC John]

Leak located (they think!!). Hose somewhere. They have the hose but not an 'O'-ring that has to go on with it (?) so the car is staying overnight.
And you won't believe how much this is costing . . . . . . :ahhhhh:

 

[OBC John]

£150? I wish!!! x3!!!

 

[OBC John]

WHAT!

As you say. I've already told them that discussions will ensue when I collect it. (Because there are also some dodgy-looking recommendations on the "health check" thingy they've sent me. For example, does anyone know what "Play in NSR tie rod inner joint" means??? No, me neither. Track-rod end is my guess.)

 

[OBC John]

One of the rods that locates the rear suspension

Not when they've put it in "Steering" section. 😕

Sent from my Nexus 10 and a Black XF-S 😎

 

[OBC John]

Update: I had a call from Stratstone late afternoon yesterday to say they needed to order a seal before they could replace the hose. Wouldn't have it until this morning so car stayed there overnight.
I called this morning (despite a promise that THEY would call ME) to be told that during re-assembly yet another component was found to need replacing ("warped" and losing coolant) and did they have my authority to order it. £25!! YES, YOU F'ING-WELL DO!!! was my calm reply. And then the 'coup de gras' . . . they won't have it until TOMORROW morning!
Now, in order to get this problem sorted quickly I booked the car in as early as I could which meant they didn't have a courtesy car available.
I'm not a happy bunny ATM.

 

[OBC John]

I guess it will, Rick.
I've looked at the workshop manual and the cooling system looks like a plate of spaghetti. I really wouldn't have wanted to start stripping that down to find the leak.
If there is a bright side to this, at least it's not a blown head gasket. Gawd knows how much THAT would have set me back.

 

[OBC John]

Thanks Jim. But I've been topping up with a 2:1 mix of water/antifreeze. Proper pink stuff too. 😉

Sent from my Nexus 10 and a Black XF-S 😎