These Videos will help you through it, not necessary to pull the plug, I've done
around 30 cars for members here, not necessary todrain any fluid i just fluid only from the
expansion tank, you don't want to introduce air in the system, I did this
4 years ago and all has held up, use OEM orings on Y pipes, not necessary
For the crossover pipe

 

The plastic elbow at the WP is a known weak point. Replace it in the new hose with the brass one from RKX.
Check the brake pressure vacuum pump. They are a guaranteed oil leak at some point. Although the RKX video is pretty good for the install, don't bother with their gasket set. The failure comes from the pump warping. Only fix is to replace the pump. Not a big deal if buy from FCP Euro. Do pay attention to torque values for the reinstall. I had to by a very low torque wrench. https://www.homedepot.com/p/Husky-40...A-03/316924568

 

FWIW I bought one of these brass elbows (not from RKX though) and the fit was quite terrible if you use the supplied insert. Try to salvage the insert in your WP if you can.

 

Here is what was left after my Symposer removal. It's an XJ but this part is all the same. One electrical plug which is empty and then a capped vacuum port as well.




I did not see if you blocked the "trumpet" off on the firewall?




One thing I wonder about is why did they use bright blue plastic for the trumpet?





With everything apart consider replacing both PCV diaphragms while everything is open and they are easy to change. I did mine with the SC in place and I also removed the Symposer and replaced the rear water manifold with a metal version again without removing the SC and I have a rear opening hood to boot! Talk about no room to work!

You can see them pretty good.




And if you look close JLR did cut out a bit on the SC lid for the PCV caps. But not much!





With the SC in place you can see we don't have much if any clearance to get at it. If at all possible avoid doing any of this with the SC on!
One tip is the new diaphragms come with the spring and plastic cap so don't worry about breaking the plastic tabs off on the old cap when removing them.
I also recommend the improved RKX diaphragms.
RKX PCV Diaphragms
.
.
.

 

Thanks for the note on the oil cooler gasket. I was pondering it. Noting the number of bolts holding it in, its overall position on the engine, and the lack of any type of corrosion in the valley, it does seem to be unlikely to spontaneously spring a leak. I was weighing the pain of doing it, if it ever does, with the risk of doing it and having it leak immediately.

@RoverJoe Only reason I was considering the flush was the sparkly bits in the coolant. Any idea what they might be? Definitely not corrosion related. They are clean and distinctly gold/copper colored and very shiny. The prior owner was clueless enough to be the type to dump stop-leak in the car, but I haven't found any sign of anything anywhere that would trigger the need. The guy I bought it from was keen to note that he was including the plug in tuning module that would add approx 50HP. Yes, the kind you plug into the OBD port. Yes, the kind that are just a blinking LED when you open them up. As I noted earlier, the water pump certainly doesn't feel like its eating its bearings.

 

The Euro AMP kit includes the brass elbow and the insert. I haven't checked for fit yet, but the retention insert from the original water pump is entirely salvageable.

The brake vacuum pump is on my list of things to check. I've got oil from somewhere, that I need to track down -- not from the vacuum pump though. The whole front of the front diff is wet, and it goes all the way over to the drain plug.



The splash guard was a bit gunky, but it's not enough to have dripped on the garage floor. I haven't gone digging there yet.

For everyone following along -- thoughts on proactively swapping all the idlers? Way easier to do with everything out right now, but with five (I think I counted right) its not exactly "cheap". The bearings are smooth on all of them. Most seem to have just a little play, but being the first time to have this thing apart, I don't know what "normal" is. Bearings are all butter smooth and silent when rotated by hand, including with some amount of pressure on them.

 

That answers one question I had about the symposer delete -- whether leaving the solenoid plug unplugged would cause a trouble code to be thrown.

Noted on the PCV diaphragms.

 

I know that VAP sells an improved idler, but that’s the limit of my knowledge on that.

 

Have you mentioned what mileage you're at? I saw on your other thread you are doing VAP pulley's. My understanding is the VAP upgraded idlers would be of benefit.

We waited until we hit 95,000 miles to do any of this stuff. Made it that far without any leaks but it was definitely due. We did the idlers along with new belts, WP and the new metal JLR factory Y pipe pair.

We did the oil cooler gasket mostly because access was easy once the SC is off (as is draining the SC oil). Also it is SOP at LPS where I met my young tech friend while I was a service writer.

The O ring on the oil filter cap can leak quite a bit if you are using aftermarket filter kits. Drips right down the front and all over the alternator.

 

Mileage is approx 38k. Origin date is 5/24/2026, so it's effectively 10 years old.

I have complete service history of the car. It's had three owners -- me being the third -- and all service has been done at the same dealership, or by me. All oil changes have been done by the dealer and on schedule -- by time, not mileage obviously. No after market parts mechanical parts, prior to my ownership.

I am doing the VAP tensioner. Putting in a new accessory drive belt as well -- it's cheap, I had to take it off anyway, and age matters almost as much as run time. I will be changing the SC oil as well, since its out, and installing the solid coupler that comes with the EuroAMP kit.

I'm walking the tightrope of "well, since I'm already in here" and "this stuff isn't normally needed until much higher mileage". I was looking at it a couple nights ago and had the passing thought -- oh, I could do the valve cover gaskets while I'm in here. That lead to -- if I have the valve covers off, I should do the timing cover seals. Which lead to -- if I pull the timing covers, then I should do the tensioner and guides. Which lead to a moment of clarity and I went inside and had a beer.

So I think I shall firm up the following approach -- things that might degrade, just from time, and are either quite easy to do with front torn apart, or are already having to be pulled, will get done. Mainly the accessory belt and PCV diaphrams in that category. Items that would be mainly mileage related replacements will get left alone if there are no signs of current issues. Actual idlers fall into this category. Any seal that gets broken gets a new gasket. I know a lot of people reuse the air cooler gasket, but if I'm already ordering stuff, a new one would be reasonable. Otherwise, if it shows no signs of problem, don't fix it if it ain't broke. Oil cooler gasket falls into that category, as do all the things my thought train led to a couple nights ago. Yes, some of them might go bad at any moment do to time and bad luck, but I'll have to take a little bit of risk there.

 

Continuing my search for glitter, I split the old water pump apart yesterday.




As one would hope, for a car with 38K miles, it looks pretty nice inside. The only item of note was a bit of corrosion starting around the edge of the impeller pocket. It's not build up. It looks like there were rough spots in the original casting, along that lip, and the coating has started to wear off and the underlying metal corrode. I'll have to study it a bit more, but its possible that could be the source. I haven't drained the catch pan yet, but when I do, I might filter it to see just how much glitter there really is in it. I might even sacrifice the impeller (this is going in scrap anyway) and see what things look like behind it.

 

The "corrosion" you saw might be might related to the sparky bits. These might be removed from surfases by an cavitation. Vehicle engine cooling systems are not an constant pressure systems, like exsample household central heating systems are. Time to time an cavitation will occur on areas where high pressure reliefs. (near impeller blades) This is complete normal.

 

I don't know of anywhere in the cooling system you would get brass from other than maybe inside the pump, or possibly one of the aux pumps but those often have a magnetic drive to the impeller and do not let coolant touch any of the actual bearing parts. On the bright side the coolant circuit is much more tolerant than the engine oil, and some sparkles are not likely to cause any further issues if they stay in there.

 

@Vasara Among other powersports "toys", we keep a boat down on the Gulf Coast. Well versed in cavitation and the crazy damage it can cause.

@RoverJoe Thanks for the input. That generally aligns with what I could determine regarding possible sources.

 

Started putting things back together yesterday -- felt good, even with a long way to go.

Y pipe installed. Took a bit of "tappy-tappy" with a rubber mallet to get it to fully seat in correctly.



The brass elbow fit in the pump well, with a good, positive lock.



I stared at the water pump gaskets for a good while before realizing both gaskets are identical and the molded ridge faces opposite directions on either side. Felt a bit silly after realizing that.



Water pump is in place and torqued down.



Thermostat housing is back in place and all the various clips re-attached. Not going to release the clamps on the pipe until I get the front crossover installed and pretty much everything back in place.




I can't imagine trying the get the rear crossover back in place, with the supercharger still installed. With everything removed, I could reach in the center gap to thread bolts in and/or feed wrenches in. Luckily, my small torque wrench fits well enough to get things properly torqued, without too much drama.



Removed the symposer pipe while I was at it. A pair of latching hose clamp pliers is really helpful there.


I just need to put the supercharger tensioner assembly back in -- it has an accessory belt idler on the back of the plate, and run the belt. At that point, cooling work will go on hold for a bit.

 

Having just done this last week, ensure that youve got the right two pin plug on the rear coolant pipe sensor. One of them went to the Symposer, the other went to the sensor. Unfortunately both will fit the sensor and both are the same colour etc!
I didnt realise this and by the time we reassembled everything, I didnt even realise there were 2 plugs so just plugged the one I saw into the sensor and had a P0118 fault code, ECT Sensor 1 high voltage. After swapping the sensor over and admitting defeat, I took it to my specialist who ended up digging out wiring diagrams and found the other socket, plugged that one in and all was ticketty boo! So if you get that fault code, it'll be the wrong plug attached to the sensor. Great thread though and I can tell your car lives where the sun shines! Mine was almost apocalyptic when I took mine off. But we do get a hell of alot more rain in blighty than you guys ;-)

 

I noted that when I took them off. For future folks, the ECT sensor connection comes off the wiring harness that runs through the valley to the knock sensors. The rear coolant temp sensor comes straight out of the big wire bundle in the back.

 

Auxiliary drive belt routed. What a pain in the rear.




Some notes/learnings. If you have the thermostat housing out, run the belt before you put it back. It will make your live that much easier. Obviously, if you are just doing a belt replacement, you just have to squeeze your hands down to get to the drivers side pulleys. For the supercharger tensioner/aux idler assembly, leave the tensioner off when you are bolting it back in place. a) It makes it way easier to feed down the front of the engine. b) The tensioner gets in the way of the bottom bolt.

With that, the cooling system is as done as it will get for a while. I need to do some work on the supercharger before it goes back in, and I'm waiting on some clips and gaskets to arrive.

 

Speaking of clips, anyone have any ideas for a part number? Embarrasingly, I'm not entirely sure where it came from. I've been making notes of anything that broke or was cut and somehow missed this one.

 

I am pretty sure they secure the hose from the throttle body that goes under the supercharger. I have seen the part number posted on the forum & will look.