Follow the instructions in the JTIS supercharger removal document found elsewhere on this forum.
Before you begin, a word to the wise, from experience. When attempting this process, the JTIS does not mention “THE SECRET” which is ……………REMOVE THE DAMNED A/C SHROUD AND CABIN FILTER to access bolts holding the EVIL EGR valve on. The EGR valve must be removed before you can remove the supercharger air intake plenum and the air intake plenum must be removed before you can remove the supercharger. It will take you many additional hours to remove the EVIL EGR valve if you don’t take advantage of “THE SECRET”.
All told, we spent about 7 or 8 hours to finally disassemble the parts to remove the supercharger, but had we discovered “THE SECRET” earlier, it would have cut the job down to about 4-5 hours or more depending on how much time you would like to waste before trying “THE SECRET”. (BIG GRIN)
SEE THE ATTACHED PHOTOS and others in following posts

 

This is not a really simple repair, but I have to say, with the expert help of
other members (see previous posts in the thread) I was able to
accomplish the disassembly with a minimum of trouble (particularly after
discovering "THE SECRET" not mentioned elsewhere).

I wanted to share this with all of you who have STRs and will likely have
the same problem ultimately (mine at 65K). I wouldn't wish it on you, but
in the interest of saving your nest egg: ENJOY

Final photos prior to sending my blower to Stiegemeier:

 

ttwotees, we all owe you a huge "thank you" for your gift to us all...allowing us insight via your tutorial and photos of your blower removal experience. Looking forward to your port/polish/pulley/ blower install.

 

Could we have some closer looks at that hose, where it failed, construction and a comparison with the new one if you've purchased it?

Does there seem to be anything in the vicinity of that cut/hole that might have caused this?

It looks to be different sizes on one end versus the other.

You mention a bulge but the photo doesn't really indicate if that's due to failure or by design.

Bob S.

 

WOW - those are AMAZINGLY helpful photos, thank you!!

I wonder if the EGR swaps sides, as I'm in the UK and the a/c shroud & cabin filter are on the opposite sides (swapped with the brake stuff). Oh joy.

 

Thanks for posting all of this Ttwotees. Man, I love this forum. Between all the experienced DIY owners and the Jag techs, I'm really getting a better sense of of all the different parts & systems, their functions, their flaws, and fixes. Knowledge feels good. Right now, I think I may know just enough to be dangerous. Not deadly, (yet,) but I'm learning.

 

I've seen some posts about what to do about the EVIL hose that caused
this entire problem - The Coolant Return Hose routed below the supercharger.
This hose has an enlarged connector toward the front of the engine and that's
where the leak occurred.

My plan is to use a thermal protective sleeve around the hose, specifically
made for this purpose. You can find it at:
http://www.heatshieldproducts.com/thermal_hose_sleeve.php
HP Hose Sleeve-radiator hose heat shield sleeveProtect rubber hoses from
radiant heat damage, increasing their life. Use to insulate air intake tubes from
radiant heat lowering your intake temperatures and increasing horsepower. Special
coating allows this sleeving to reflect and dissipate heat. The special braid of sleeving
allows it to have an expandable inside diameter from 1 3/4" to 2 3/8". Thermal Hose
Sleeving is capable of withstanding 1200°F continuous. It may be fastened using
Thermal-Tie or hose clamp.

The website mentions a number of retailers where you can buy
this sleeving. Perhaps a silicone hose would be a better answer,
but I don't have time to try to find a manufacturer who might
be willing to make a copy of silicone. I'll have to leave this to
another researcher.

We've also determined that the rear bolted support on the
supercharger intake tube needs to have a similar notch cut
in the bolt boss in order to facilitate reinstalling it. When we
do this during installation in a couple of weeks, I'll post photos
and text.

One note, my list of replacement parts included only one of the
C2C11477 water outlet seals, but you need to order two of them.

I'm trying to find a reasonably priced EGR valve replaceent and
the heat riser tube. Many of the parts supplies I've checked
price the EGR substantially above $200.00 and the heat riser
above $100. I think I can beat that and will let you know what
I find out.

I'll be sending my blower laer this week to Stiegemeier and will
post when it comes back the following week.

 

I made a close-up of the hose. The rupture is very small, but under high pressure it
can empty your cooling system very quickly. The hose is about 1/2" diameter for most of the lenth, but the pump end does have an enlarged section about 4" long
and that's where it ruptured, but where it connects to the smaller section, it was
also enlarged and just a matter of time before that ruptured too. I'm suggesting using
a braided thermal protective sleeving that can be found at; http://www.heatshieldproducts.com/th...ose_sleeve.php

 

Lots of pictures of the failed part would be great!

That hose looks like it has a step-in-size fittinng on the larger end. Can you see any evidence of rubbung or chaffing or does it appear that the hose delaminated or ... ?

Maybe removing the larger piece of hoiase from the fitting and having a look inside of it?

What's the fitting made of?

It's a not really a high pressure application just whatever your cooling system generates which isn't much.

I don't know that the heat sleaving you selected will do all that much from a temp standpoint. This is a strange failure to be heat related unless that was just very poor quality hose. The heat sleeving is for really high temps like near exhaust ports, headers etc. The coolant running through the hose and under the supercharger are not going to be that kind of hot.

The Jaguar tech guys must have some thoughts on why you'd get a small hole like that and if that's where these hoses typically failed.

You want to fix this only once.

Bob S.

 

ttwotees;
Is your EGR bad too?? Or are you just replacing it because it's so hard to get too??
Thanks!
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I will make more photos of the failed coolant hose this afternoon and try
to answer questions. I don't think there is any question that the failure is
heat related. If you look at the amount of bulge expansion in the hose, it
seems obvious to me that is was caused by the lack of resistance of the
rubber hose to heat and I can only guess that the puncture was a result
of the heat stress. If someone out there is capable of running some kind
of test to determine cause of failure, I would be happy to send them the
hose.

I'm certainly open to any suggestions about how to protect the new hose
before reinstalling the blower, but I think the thermal sleeving I found is
the best answer so far.

Please help us all out if you have a better suggestion.

 

I'm not trying to be contrary just trying to figure out what's what here.

What on the engine is right next to that larger portion of the hose that might either be causing extra heat transfer or could possibly be rubbing/poking at the hose?

If you look inside the hose is there more deterioration on the inside than on the outside thus imdicating that the heat or pressure problem is from the coolant and not external?

The hose is of course supposed to be bigger on that end and if it's thin walled it could bulge a bit. Maybe that part of the hose assembly is just the weak part of the assembly?

Can you tell what that size change fitting is made of?

Maybe the bigger end needs to be a better grade of hose like silicone.

Thanks for sharing your "fun" with us and I'm looking forward to the pictures. It will be interesting to see if the replacement hose has had any engineering changes made to it.

Bob S.

 

Hey Ttwotees, would you happen to know, or could you approximate, the dimensions or bolt pattern of the blower outlet?

 

The larger end of the hose is heavy corded rubber and I don't think it's bulging due to the thickness. The hose lays below the supercharger and
runs from the front of the engine to the back through the valley, so it's
catching heat from the blower and from thie cylinders adjacent and there
is little air passing through this area. The large end of the hose is approx.
3/4" I.D. and the small end is approx. 5/16" I.D. Pictures are below. I laid
my new hose next to the ruptured one for comparison.

Regarding the bolt pattern, the bolt holes are approximately 3/8" dia. and
the bolt centers are approx. 4-3/4" on centers.

 

I'd be tempted to replace the bulging portion with a short length of silicone heater hose and leave the smaller portion alone. There must be a superheated pocket of coolant in that spot at times but without instrumentation it's hard to know. The heat jacket won't help with that possibility but the silicone hose defintely will protect agiainst both possibilities. If that larger portion was double walled there probably would be no issue either.

Good luck with your repair and thanks for showing us the details.

Bob S.

 

As I understand it, the hose is part of the coolant circuit through the TB (throttle body). From JTIS, it appears next to go via the engine water pump. The only time I can think it's under pressure is when a hot engine is switched off (and then heat soak occurs). It's then under pressure for a long time (until the engine cools). Anyone have any other ideas?

I suppose there's a slight pressure increase any time the coolant heats, as water expands when hotter. Anyone know how much the pressure will rise during engine operation? On my STR the highest I've seen is 95.5C (204F) but I've not watched it much That's the ECT figure, which I think is in the relevant coolant circuit.

If that hose is a weak point in the pressurised coolant circuit I want to fit a more accessible weak point!

A different coolant expansion tank cap springs to mind. If it lets hot vapour (steam) out it wouldn't be ideal but the current failure mode looks horrific.

Are there pressure-measuring devices I could fit fairly easily to that coolant circuit? I just mean a sensor, I can wire up some electronics if need be.

 

It's not a high pressure circuit even when you turn the engine off. Your radiator cap takes care of that. If it's bursting under 230 psi or what ever the system's pressure is then it got damamged or softened up before it burst. It's not like it's right next to any part of the exhaust system.

The Jag Techs must have some idea why this happening. I'm surprised to see that the replacement parts appears to be identical unless it's because that's an old stock piece.

The compact packaging of modern engines and their accessories makes for very expensive repair times.

Bob S.

 

I agree it's not at all high pressure. Just sustained (I think).

I think this is the 4th STR with this problem I've read about online over the last 18 months

 

Whatever the cause, quite a few seem to have the problem, but with the method
I've found, it reduces the time to repair. I think now that we've completed the
disassembly. the entire job would take less than 6-7 hours. I know that's still quite a job, but not the horrific time or difficulty it would have seemed to take before. I also believe that with some extra caution and protection you can prevent this from
happening again. Too bad Jaguar hasn't done anything about it. Techies do you
have any input ?

 

You got your parts pretty quick!!! Do you have the two hoses laying on the hood of your STR?? I hope not! See how long it takes to get your blower back from the shop?
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