Did a follow up service last week for all of these repairs, an oil & filter change and another tranny fluid exchange.

At the time I didn't have enough fluid to due a second flush because I goofed and turned the engine off WO the fill plug in place and so I lost a couple of fresh quarts that way.

So I decided to get some more fluid and tackle the second flush at the next oil change.

This time I wrote out a very simple check list guide as the original threads on this procedure take a long time to refer to and one of them confuses the drain with the fill plug. Perhaps I'll post my step by step checklist here later.

Having already done the pan and sleeve replacement just a fluid exchange is a lot easier this time around. The idea being to dilute the amount of original fluid still in the system by half once again.

So my air pressure fill bottle/pump (see other thread) worked slowly but very slickly once again. Also, holding any ordinary tall plastic pail instead of a catch pan under the drain plug works far better for the fluid drain IMHO. Zero splatter. That darn fill plug got terribly tight again and was a PITA but it came out.

When inspecting all of the work I did earlier this year (a lot!) I had zero leaks or drips and those changes in the belly pan screw lengths have prevented the damage to the pipes shown earlier in the thread so everything was great!

I also tackled the erroneous low cooling level sensor issue and as expected it had become knocked out of place on the underside of the reservoir. I had to remove the engine cover, front valence cover on top of the radiator as well as the intake tract hose from the engine and the air cleaner assembly. Thanks to using some Dow 111 silicone grease on those they came off quite easily WO needing to even touch the air cleaner assembly.

But I did discover that I had forgotten to replace one of the intercooler hose clamps and yet it never leaked at all! (see photo)

The reservoir continues to weep at the nipple as it has since I bought the car and even after a warranty change out. It's not really affecting the coolant level so I'm just not going to worry about this any longer. ZERO leaking shows up on a pressure test so what can one do? (see photo)

We took the car on 1,000 mile trip the last 6 days and everything worked fine with no fluid drops or leaks upon returning home.

Soon it gets put away for the winter and next spring new pads and hopefully just having the rotors turned.

 

I suppose that means the SC intercooler pump is very low pressure (or not working).

 

The pressure comes from that of the cooling system as set by the cap since they share the reservoir but not a flow path. I doubt that the magnetic drive pump does much to add any head pressure. I would have thought it might have weeped a bit just from the system's pressure but apparently not. Perhaps the small diameter of the hose is the reason?

 

I don't know but it's handy it didn't leak

 

Yes it is!

Even small leaks are quickly detected by smell.

 

So here I am again 2 years and seven months later with enough of an engine oil leak to drip through bolt holes of the under tray and make a nice mess of my driveway again

It's cold here now and snow will soon arrive so the car gets parked till spring. I won't be putting it up on the jack stands again to have a look see till then.

I don't know what is leaking but those oil cooler hoses were brand new and I was DAMN meticulous about making sure there was no interference anywhere. At my last oil change everything including the tranny cooler lines repair was bone dry.

I don't know yet but I think these frigging cooler lines have failed once again.

About a month ago I hit a big pothole on the from RH side. It didn't bend the rim that I can detect but it did put some rash on the lip and knocked about 15 lbs of air out of the tire. That tire has early wear now on the outer edge.

So yesterday I had the car inspected at my top notch tire and suspension shop.

Both upper ball joints need new boots but there's no appreciable wear.
The car drives true and straight with no noises.

There's zero impact damage in evidence on the plastic undertray.

Is it possible that the massive and it was massive jolt somehow caused one of those oil cooler hose/pipe assemblies to start leaking so soon?

PS I have the worst GD luck with fluids on this car.

I also noticed that the radiator expansion tank is still leaking and all three of them I've had on this car do the same GD thing. They leak along the seam but they always test OK on a pressure test. It's a slow leak, this time about 1/3 of an inch over 4.5 months.

 

You should know by now that ANYTHING is possible regarding fluid leaks on these cars....

Where are you sourcing your coolant expansion tanks? If you have been getting them all from the same vendor, I would try a different source next time....

 

They're all official Jag parts.

There was the original (I think?) that leaked.
That got replaced by the local Jag dealer. It leaked too!
Then a nipple broke off that and I sourced the same part number on the internet. It leaks as well. It has since initial install too. But this is minor compared with replacing those pipes/hoses to the coolers.

I wonder if the car would run well enough with no oil coolers? Then at least I'd have no leaks.

That or maybe I could instal a Laminova oil-to-water cooler like I have on my race car and get much simpler routing of the oil hoses but EVEN MORE RADIATOR HOSES! Not to mention the additional load on the cooling system.

It really does suck.

I may just be force to eliminate the those complex bent aluminum pipes and go all hose with touch abrasion wrap coiled around them instead.

I suspect they're leaking at the stress points once again but ...

Perhaps a rat got in there and bit a hose?

 

Damn, that sucks. Sorting through my 04 XJR. I thought my trans cooler lines were good but I found the upper hose near the radiator with a slight weep/leak.

Known issue. I have replacement lines new from my other X350. Not looking forward to that job. Thanks for the tip on the belly pan bolts. Going to swap them out with shorter bolts as I just sorted a replacement belly pan and just installed it.

 

So far my repair for the tranny cooler lines seems to be holding. I didn't put in new lines I trimmed the metal lines back a bit an put in longer hose portions via compression fittings further down the metal lines so it's more pliable for engine movement putting less strain on metal - to - hose fitting.

Oil cooler was OEM. It'll be "interesting" to see what & how things failed this time.

 

You absolutely nailed this one!!!

Just peeked under my belly pan and you can see the two outer bolts literally touching each metal pipe and this is with the car stationary. I just recently sourced a replacement belly pan, actually an intact one with foam, etc.

Glad I came across this thread before removing the car off my ramps and driving it and causing more issues.

Swapping those two outer bolts out for 6mm X12 bolts now!

Thanks again!

 

Here's two options for the front belly pan bolt replacement.

I went with these, which eliminates the washer entirely:

https://www.autozone.com/nuts-bolts-...uestid=5119225

The below bolts would need to be used with a washer though

https://www.autozone.com/nuts-bolts-...olt/551609_0_0

Both lengths are 1/2 of the original 24mm M6 bolt size...

 

Even though I found these rub points they weren't source of failure but very well could have been. After I adjust my length I tested it by banging on the belly pan to make sure the click of the screws against the aluminum pipe had really disappeared. That pan is not rigid at that spot and I suspect it actually flutters or bounces up and down over bumps or POTHOLES! Did I mention that the potholes here in NJ are so bad year round now that when it rains hard the EPA immediately categorizes them as new wetland areas and we have to avoid them assiduously or face federal fines of $50K ...

 

Fully agree as I'm in NJ too. It's funny as when I looked at the metal near where the bolts go from the belly pan on the ends you can see where the bolts touch the metal.

Bad design flaw all in all but easily remedied...

 

Just an update to this. I'm not engaged in a major service for the dreaded under supercharger hose failure. But before that happened I notice that since my last oil change in late last summer (car sit's all winter) I had oil dripping again! Last time it was just a loose oil filter so I ASSumed I'd screwed up and the filter wasn't on tight enough. You're not supposed to tighten the crap out of them. Well once again it was loose so it weeped.

I'm blaming this on the filter manufacturer, NAPA. They're supposed to be made by WIX which I've used on this and other cars and they're excellent but this NAPA one is crap and I have a case of them ...
Perhaps the rubber gasket material shrinks slightly over time?

So skip the NAPA oil filters for this car.

 

I tighten oil filters a bit tighter than is recommended. ;-)

 

Nah that didn't work, this is the second failure.
So if you look at the comparison in these photos you can see how the NAPA filter has a much narrower seal and it has ridges on it!
I can't beleive WIX makes it this way for them so maybe something has changed?
NO NAPA!

 

Are these ridges consistent?

I recently changed the oil pan gasket on my pickup (351W) and the new gasket had similar ridges. Works like a champ, BTW.

My guess is the ridges create several narrow bands that compress more than the valleys. More localized compression equals better sealing? That might also explain why the seal overall is narrower, too. I highly doubt it's NAPA (or Wix) going cheap. It's probably a new design meant to give better sealing action without changing the installation torque.

The big question: Has the leak stopped with a different filter brand?

 

It never leaked until this brand! My contention is that this just doesn't work in a spin on seal situation.
It's become loose and leaked twice with this brand.

No mas. The WIX brand works great on all my cars.

Ruffles have ridges but this ain't a snack dip application.

 

Okay, I should rephrase my question:

Have you since tried a different brand, and the leak stopped? Or is the suspect filter still installed and leaking?

When the problem started is very important. But just as important is what action stopped it. No mention of the latter yet, unless I missed it.

Not trying to bust your butt or doubt what you have observed so far. It just seems we haven't reached the end of the book, that's all. Maybe it wasn't really the butler after all...

FWIW, I once had an oil filter seal weld itself to the block. It came loose from the filter during replacement. Didn't notice it and installed the new filter over the old seal. In my defense, this was when I was young and before I knew everything like I do now... Eventually it leaked so I replaced the filter again, but no joy. When I finally got suspicious enough to inspect the mating surface, it still wasn't obvious at first. This wayward seal looked like part of the engine block casting, as if was metal. It was the same width as the machined surface, so it blended right in.