Hi guys,
Several months ago, I had the pleasure of a serious coolant leak that I took on by myself (with the help of a couple of friends!). It was a pretty major repair for me and I thought I would try to make a tutorial for anyone that is doing research on 2011 Jaguar XJ coolant system upgrades/repairs

The problem:
Severe coolant leak. I was hemorrhaging coolant. Independent research + problems with other vehicles' coolants systems pointed to four possible culprits:
Front Crossover coolant pipe
Rear Crossover coolant pipe
Water pump tube connector
Water pump
Based on where the coolant was leaking from, I suspected the water pump, water pump tube connector, or the rear crossover coolant pipe.

Research phase:
Luckily, there are actually a few different YouTube video tutorials out there for changing out coolant system parts. Of course, none of them are exactly 2011 XJ (and if they are they're not in depth enough), but I was able to get the general gist.
Here are the links I found particularly helpful:
After watching those videos, I decided to go ahead and order new parts for all four of the above mentioned suspects. If I was going to take off the exhaust manifold, I might as well replace the front and rear pipes at the same time, as well as the water pump and tube connector since it was already going to be easier to access. Ordering parts is another monster. I took a chance on aluminum upgrades for the connector tube and rear pipe and ordered OEM water pump and front crossover pipe from Amazon. Spoiler: the water pump actually didn't end up fitting. Wiser and older now, I can confirm RockAuto is the only place you can get decent parts (more on Parts Geek failures to come!). these are the part numbers for each. Again, rockauto has them, but especially for the connector tube and rear crossover pipe aluminum upgrades you'll need these if you're ordering from Amazon:
Coolant reservoir- C2Z29118ES
Reservoir hose- C2Z4547
Front crossover coolant pipe- AJ89664
Rear crossover coolant pipe- AJ814007
Water pump- C2Z21781
Water pump connection- C2Z 18658
Water pump O-ring- AJ8 11539
Oil cooler seal- 38990585

You will not need all of these, but good to have in case you need them

Doing the Work
1. Put your jag on ramps or a lift. Make sure you block it. I already had ramps, luckily, but you have to drain your coolant, and to do that you've gotta get under the car. You'll want to start earlier in the morning, also. It's about a 4-6 hour job, so naturally, you should be prepared for an 8 hour day.
2. Undo the splash guard. Most of the bolts are T30
3. Drain the coolant

• On the driver's side (left side of the car), you'll find the coolant drain plug while you're under the car. There is a small space for you to fit a flat head screwdriver. Push a flat head screwdriver up there and push the plastic tab that provides additional support in. With another screwdriver, you can loosen it. This was one of the most infuriating parts of the job. We actually ended up hammering an ice pick into the plug itself and using that to just muscle it out. A replacement plug is cheap if you have to end up doing this.
• Make sure the reservoir is empty too! Do what you can to empty out hoses before you continue.

4. Remove the engine cover, then the central air intake and the throttle body

• We did not fully remove the throttle body, but did unbolt it and move it out of the way

5. remove the fuel line that crosses over the intake manifold. The passenger side is easy and is I think 14 mm if I remember correctly or somewhere around there. You will need a set of pliers an possibly some kind of leverage bar to get the right side bolt off. This was another major challenge for us.
6. Remove the intake manifold cover. These are I believe 10 10 mm bolts on either side. This opens up the front crossover coolant pipe and gives you the opportunity to start looking at the rear coolant pipe as well

• VERY IMPORTANT: Make sure nothing gets into your intake manifold. We covered our holes with duct tape before we continued.

7. At this point, I got to work on the water pump. If you're only replacing your water pump or water pump tube connector, this repair is a lot simpler and covered entirely in one of the videos linked above. Because I was intent on replacing everything if I could since I didn't know exactly which part was faulty and was going to have access to everything, I did this all at once.

• Remove tension from the serpentine belt
• Detach hoses with pliers
• 4 bolts (T30)
• One weird push in attachment that is connected to the thermostat housing. This was another challenge for us. We couldn't get it off. Luckily, when we got in there, we found out the new water pump didn't line up right anyway so we ended up putting the old pump back on. Friendly reminder to get your OEM parts from rockauto, not some random Amazon distributor

8. Remove the front crossover pipe. Use pliers to unclamp the hose it's attached to. You'll have to wiggle/pull it out and it may break because the ends of the pipe tend to get stuck in there and may be corroded already. Make sure you remove any pieces left over from the pipe after you pull it out. Putting the new one in is pretty straightforward
9. Remove the water tube connector. This was the culprit in my case, luckily, because it turned out we didn't have exactly the right tools we needed to take on the rear crossover pipe, although we were able to confidently identify that it was not leaking. When you put the new one in, make sure you push, then twist until it is secure. The design on these things is atrocious and if not put in just right, it'll fail again just because it can't hold up to the pressure.
10. Working in reverse order, put everything back together the way you found it. You'll need 2-3 things of coolant, which I've linked . You may need to burp the coolant system before you try and push it too hard. We let it idle for awhile and then drove it with no problem.

I also attached this document I worked up which has a little bit more nuance with the intake manifold cover removal. I made it before I actually did the repair as a part of my research, but it actually held up pretty well when it was time to get my hands dirty. I hope that anyone trying to do a DIY repair on their jag coolant system finds this helpful! This should work more or less on 2010-2012.

 

Excellent post and work!

 

Welcome to The Forum! And this is quite a write-up early on in the first day too.
You should be able to find a lot of helpful info from previous posts from many that have experienced things that you will depending on how long you keep your XJ.
The 2011 XJ isn't much different from the rest of the run, many common parts & systems all the way up through the 2019 model year.
And many of us have done all levels of work on the cooling system; there are loads of posts that discuss various cooling-related topics on all engine configurations, largely the 5.0L V8 AJ133 that you have in your 2011 XJ.
I'm not familiar with a FRONT cross-over pipe. When I replaced all coolant parts on both of our 2012 AJ133s, I didn't come across a front cross-over, only the rear "cross-over" formally named the heater manifold.
You might be referring to the coolant output pipe that attaches to the block under the front of the intake manifold? Depending on if you have a supercharger or not, it's a different part, but either way it's the coolant output pipe.


I would NOT suggest removing either of the exhaust manifolds to do any work on the cooling system. Only if you have to pull the heads for bad head gasket(s).

Rock Auto is a great source many of us use for many parts, the coolant pump generally NOT one of them. The best choice for the coolant pump, and there are MANY posts on this, is the genuine JLR pump.
I've been through a couple of other self-described "OEM" pumps, most if not all from Rock Auto, and none of them last long or maybe even work well from the start.
As big a fan as I & many forum members are of Rock Auto, it is NOT the only place to source parts. There are several dealerships that have online sales, there are popular & reputable suppliers such as FCP Euro, AutohausAZ, others if you read some of the existing posts with detailed chronologies of things replaced & where the replacements were bought from, AND how those suppliers performed as far a support, etc.
Those I just listed include genuine JLR parts too, not just aftermarket that unfortunately Rock Auto only sells..

You do not need to remove the throttle body. It stays fully attached to the intake manifold, which DOES have to come off...ONLY if you're replacing the rear heater manifold pipe, the front coolant outlet pipe (is this what you're calling the front cross-over?) and/or the hose that connects the throttle body to the rear heater manifold. If you're just replacing the coolant pump and anything on the front of the engine, no need to remove the intake manifold.

I'm guessing you mean the actual intake manifold itself, not the acoustic/vanity cover that covers it.
And If you can, please add a picture of what this front cross-over pipe is.

If you did not replace the rear cross-over (aka heater manifold pipe) unless it was replaced within the last 70k miles or so it will be failing on you, often catastrophically as in blown head gaskets, warped heads & possibly block unless you can shut the engine off pretty much immediately when it fully fails (the initial failure of a weep or slow leak is easy to ignore or not even notice until it's too late).


The short pipe that connects the rear of the coolant pump to the oil cooler does need to installed carefully and in the right position, or it will likely leak again. They have held up to the pressure without a problem as long as they're installed properly, with care to orient them properly and ensure the front & rear seals are properly seated without getting jammed up and cross-ways.

You may have gotten lucky, but it's often and highly recommended to use a coolant system test & fill vacuum tool to refill the coolant with as little chance for error as possible.
Such as this popular one that many of us use:
Cooling System Test and Refill Kit
Otherwise, refer to the various posts that go through the dance of burping the system at the purge port. It's worked for some.

There is a whole lot of useful experience and information in this forum that you may benefit from reading, including cooling system service, failure, repair etc.

 

Thank you!