Tough call. Given how tricky I've personally found successfully refitting the pump to be, if it was me I'd leave it until it actually shows signs of leakage, though I can see it's tempting while the supercharger/chargecooler is off.

The rear pipe is a known failure point because it's two sections plastic-welded together, but the plastic pipe behind the waterpump, while a pretty terrible design, is definitely more resilient.

Sounds good, I'm leaning towards doing it later as well. I'll definitely be checking all the bearings for play/wear though.

Thanks!

The "couplers" are actually o-rings - these are included with a new crossover pipe - but the part number is AJ811600.

I get all of the part numbers from an online copy of the EPC available here: https://partsfan.com/jaguar/ww/1689/1687/ - you need to register (for free) to get images/unlimited views but it's worth it as the diagrams appear to basically be a copy of the EPC that the dealers use.

It doesn't get updated so some of the part numbers are out of date, but you can usually Google the old part number to find the replacement one.

You sir are a legend. Thank you!
I noticed that after I posted that comment. Thanks so much :D

Davetibbs I have looked in threads and on the JEPC but I can't find the part number for this under super charger hose for the 5.0L SC engine?

https://cimg2.ibsrv.net/gimg/www.jag...95a210da7d.jpg


Did I miss it?
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I changed water pumps on both my XF's when changing all the plastic. When the intake manifold is off, which it needs to come off to change the plastic pipes, it's super easy to change the water pump and make sure everything is lined up correctly. Like super easy. So I would definitely change the water pumps if I had to do it again.

Plus, I change the pulleys and tensioners and belt so I don't need to worry about them either. Yes, it's a lot of extra cost in parts, but since I do my own work, the massive amounts of money I save in labor means I can spare a little of those savings to have the best parts.

That hose can be found on the diagram for the throttle body (I guess because it connects to it?), rather than any of the engine cooling diagrams.

AJ813614 (which replaced part AJ812140) should be what you need, but see if you can verify.

https://cimg9.ibsrv.net/gimg/www.jag...32f854d34d.jpg

I replaced the rear coolant cross-over plastic pipe and serviced the supercharger on my mom's V6 yesterday but noticed the valve @Bigg Will spoke about was "open" (see item outlined in red). Before reinstalling the supercharger and intake manifolds, I spun it to the closed position but it sprung back to the way it appears in the image below. Any thoughts? Is the motor that controls that valve (the one with the wide connector outlined in blue) broken?
All help is appreciated

I'm not 100% sure but I think the default position for that valve is open and the motor closes it (either partly or fully) depending on throttle input, load, revs etc.
It's the SC bypass valve so more boost when it is closed and less boost when it is open.

That makes complete sense, I was confused with the initial comment/suggestion. Thanks!

Next up, replace that rear diff pinion seal and fix that rear diff leak once and for all (hopefully).