My wife went on a 20 mile trip, she called me to say just before she arrived the "coolant low" light came on. I told her not to drive it, I loaded up with water and drove to her. Fired it up, and couldn't see "water" leaking anywhere. The coolant tank was low but not empty. I started the car (2011 XF NA, 49k mi) and continued to inspect it, no obvious leaks anywhere. I topped up the reservoir, took about a half gallon.
I Drove it all the way home, and when parked, checked underneath - no obvious leaks. Went in, had lunch, came out and there was a three foot diameter puddle underneath the car. Really strange, I had told my wife that we were lucky and it was probably a leaky water pump and therefore why it was a slow leak.
Something obviously just crapped itself about 20 minutes AFTER the car was parked! It's hard to tell with my two piece stainless under tray in place exactly where it's leaking from, but it LOOKS like the leak is from the back of the engine block - I assume the dreaded brittle plastic crossover?

Got lucky I made it home ok! Time to buy all the plastic junk and waste a couple days.

 

Yes sounds like you know what to do.
Has the water pump been replaced yet?
Are you planning to do the rear water manifold as that requires the SC to come off.
Since you have the NA version you don't have to mess with that but not sure if the intake manifold needs to come off to get the rear water manifold?
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The water pump was replaced at 12K miles due to leaking. I think I'm going to replace it again, just because they've had about 50 different water pumps since 2011 so I assume even my replacement is not optimal?

Luckily no S/C but from what I read it's still a disaster of a job, but yes it HAS to be done otherwise what's the point in replacing the rest?

I'm not looking forwards to this, but the car has to be fixed. I still have a non functioning bank 1 CAM phaser too that I have delayed in trouble shooting.

 

I am curious about one thing. Has Jag ever changed the material that these inferior, failure prone plastic pipes are made from so that they don't so easily get brittle?
Or am I just buying another 49K miles of driving?

 

You are just buying miles and time. All the plastic bits in the engine should be looked at as wear and tear items at this point.

 

I stripped off a bunch of crap from the top of the engine, wiper blades, cross brace, that black plastic two piece cowl cover thing, the fuse box, cabin filter "box".
Also, the undertray etc. Still can't see crap!
I pressure tested it - oh joy, the old memory of Stant 12023 or 12026 reared its ugly head again LOL - and it's pi$$ing coolant out on the RHS at the back of the engine block. Exactly where from I haven't yet got a clue.
I absolutely HATE modern engines, so much stuff jam packed together, a DIY nightmare.

 

Actually yes the failure prone plastic stuff all has large clunky square seams that look like this;




I have attached a Jaguar TSB that shows the old thick square seams and the updated smooth seams now used.
Is it any better? It seems to be as there is not much reported after these have been changed out.
See the attached TSB for pictures showing the difference.

kenc are you aware of the rear water manifold? That would be my guess on your leak.
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clubairth: Yes, I am assuming it's the plastic "heater" pipe behind the engine. In a sense it couldn't be worse, but in reality even if it were another pipe or hose that went instead, I'd STILL have to replace that heater pipe, it would be a ticking bomb otherwise.

Anyone k now of a good discount source of parts? The places I used to go to for OEM parts cheap have all gone, best I've found so far is roughly 20% off at jaguar merriam.

Strange: the part numbers in that TSB don't match up with the XF. At least not the 2011, it does claim 2012 on but I didn't think they were any different?

 

They're not any different - I fitted the latest part to my rebuilt 2010 engine.

Btw if the plastic tube on the back of the pump leaks enough, it can actually drain out towards the back of the engine despite it being mounted near the front. Worth shining a light in the gaps between e.g. oil filter housing and coolant pipe to see if you can see any coolant behind the water pump.

 

I didn't see anything around the water pump, but when I pressurized the system it peed out of the back passenger side of the engine.

 

I'd guess the under tray and "diaper" absorber mat caught most of the first leak and then it started showing itself under car in a delayed way..
my theory on the plastic parts is they likely last much longer in the OEM climate. Much cooler in great Britain than TX and AZ and CA where most of the posted plastic problems seems to originate. Age and heat cycles for sure. But the extremity of heat cycles in your warmer climates cannot help matters.
not sure if your N/A car is same job as the S/C model, but it can be done - going to need patience. You will likely reach point of despair, and wonder if car will ever run again.. There's more plastic back there than just the crossover pipe.

 

After it cooled a little from our 102 deg day, I pulled out the air boxes and "manifold" to the throttle body. As usual the 2010 XFR online workshop manual was totally useless. Thought I'd look up "removing intake manifold", good luck with that. Absolutely no useful information on anything.
Never thought I'd think back on Haynes and Chilton with fond memories.

Are we literally on our own for everything, or is there something useful for a NA 2011 XF?

 

LOL, at every turn there's a challenge. The block drain plug is an allen socket rather than something you can put a socket on (ugh two different uses for "socket")
I have some pretty large allen wrenches, but nothing this size, looks maybe 16-19mm but I couldn't get a caliper in there. So now, I'm going to have to make something on my mill. If this is NOT the drain plug please let me know!

 

The fastener shown in the picture is NOT an Allen type. It appears to be a Torx, perhaps a T50 or T55

 

Not sure why you think you need to remove the pug there or why you wou;d want to use an allen wrench?

You don;t have a set of these?


And these?

 

I want to remove it because I want to drain the coolant from the block.

Yes, I have multiple sets of torx up to T50 which is not even HALF the diameter necessary.

It is an allen socket,not a torx, and I am guessing 17mm.

 

Why are you draining the coolant from the block? (curious) I've never done that and have driven all types of cars 150-250K miles

Anything special about these engines?

 

Just curious, but it is safe to put water in the coolant tank if it is low? I assume prefered to be distilled and cannot be freezing temperature climate?
Good to know just in case I get a leaking water pump or small leak sometime.

 

I don't see why using water as a temporary measure would be bad? I did, but it's another reason why I want to open the block drain plug to get back to a known situation. Tap water is better than no coolant!

 

I can confirm that the block drain plug for the 2011 XF is a 17mm Allen. I can also confirm that the darned thing is too tight for me to risk cranking on it any more to get it out. Maybe it's loctited?