Interesting…I don’t think it is actually brinelling …which is excessive local static loads which exceed the material elastic capacity…and are able to be felt as indentations in the bearing races…but rather “false brinelling” which is
“ …a bearing damage caused by fretting, with or without corrosion, that causes imprints that look similar to brinelling, but are caused by a different mechanism. False brinelling may occur in bearings which act under small oscillations or vibrations.”
I saw this on my rear bearIngs as well but was puzzled at the lack of detectable surface defects that normally accompanies actual brinelling…so left them alone…!!! Dammit…
MatFurness
Thank you for your comment on brinelling, indeed we all will have different opinions based on our experiences. Both brinelling and false brinelling are reason for bearing rejection and in any event I would suggest replacing these bearings.
My own experience contributed to my original comment, and from current evidence I still retain my original view. With this in mind I have added below a little to my initial comment, which may be of general interest.
As a formerly fairly high user of Timken bearings I kept very close liaison with Timken technical personnel whilst working on Military and Automotive problems across, and in, some 56 countries. This provided first-hand experience of the various taper bearing problems directly from the World’s leading maker of taper bearings.
The “quotes” below are taken directly from a Timken Technical manual in connection with Brinelling and False Brinelling
In the Jaguar installation in question the rollers only partially rotate under frequent impact loads and cause this plastic “deformation due to extreme or repeated shock loads.” Timken list, show and advise that this is what they term Brinelling.
Initially the damage will be seen as dark shadowing but no undulations are felt. If bearings exhibiting this damage are not changed in the worse cases the bearing will suffer transverse cracking, in simple terms the track breaks. However, before that stage the worn undulation points will form a ratchet action and try to rotate the tracks in their housings (most readers will have witnessed bearing tracks loose). This damage can be expensive to rectify.
Now examine Timken’s comment on False Brinelling, “False Brinelling is recognizable by grooves worn into the raceways by axial movement of the rollers during transportation”
Note that this is a condition produced before the bearings are fitted according to Timken and I have witnessed that situation.
This False Brinelling is often mis-understood and from personal experience I know it can be a particular problem with extremely large bearings over 12 inch (300 mm) diameter. It can generally be prevented by careful and thoughtful packing.
I trust that my comments are enough for you to agree the reason for my initial comments.
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Thank you gentlemen.
But credit is due to Ron Moore, Craig Sawyers and Kirby Palm.
I just substituted the suggested National 471652 single lip with the more suitable SKF CR11124 double lip seal.
All details are in the Book.
Exhaust
Heat resistant paint.
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Someone was there before… again… Right rear silencer, with big RH marked on it, was on the Left side and LH on Right side… intermediate silencers were misaligned… and very well stuck together of course !
Firegum was used in all the joints.
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And polished tail pipes for a total bling effect !
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Unfortunately I am still of the opinion that the pictures show “false brinelling”.
Brinelling is where the bearing surface has failed in compression due to an excessive static loading. The term derives from a hardness test Engineers can use to determine the surface hardness where a ball is pressed into a surface and the magnitude of the indentation can be used to assign a Brinell Hardness to the material. The material has entered the “post-elastic” zone and does not return to the original position. It is “indented”.
The bearings in the jag hub are not subject to any extreme shock loads …especially with regards to the axial capacity they possess…they spend their whole life supporting half of the back half of the car…say 500kg…and their are two of them…so 250kg each. A bearing of that size will have a static capacity of a couple of tonnes so the load is very low …and the stresses not even close to the yield point of the steels used in bearing races…even with aggressive shock factors applied.
The information in your Timken manual should make the clear distinction between brinelling which is “deformation” …and “false brinelling” which is more to to with “fretting”…a different phenomenon.
Hey Arist,
This is a bit off topic, but I just noticed the rear badging on your cat in those pics. “XJS Vanden Plas”??? This is the first time I’ve ever seen the VP designation on anything but a sedan … What the heck is on the VDP XJS model that is not on the base model? 
btw, are the 5.3 tailpipes supposed to kinda flare a bit to the outside? This XJS that I just bought online - the tailpipes looked like that in the listing pics, which to me had me worried they were bent from possibly hitting something underneath the car. The 4.0 pipes are straight and go straight back. 
Not sure I would agree that the suspension is not subject to extreme shocks, hit a pot hole at speed and that is going to send some serious shock waves through every part of the car.
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Robin
These are not “extreme” shock loads in engineering terms.
Look a the position of the bearings. They are held in position by soft springs on the top and nice fat rubber tyres on the bottom. The tyres are the “appliers” of the shock loads and they are extremely “soft” in composition and via the compressed air in the tyre…and all the bearing has to do is accelerate the lower arm which has very little mass. A reasonable shock load is when a hammer hits a nail head…steel on steel. An extreme shock load is a large hydraulic impact hammer which will smash through 250 thick concrete. The jag rear hub load is in the low end of the spectrum. A reasonable clue to the magnitude of shock load is simply noise …which is an inevitable byproduct of the impact energy.
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Looking at the picture, Aristides - I’m a bit apprehensive…
The ‘spacer ring’ is not really a spacer? Isn’t it there to keep the outer race of the bearing in place? The extra thickness of the wire you used doesn’t seem to fit entirely into the groove - and may slip out under load, pushing the bearing out…?
No distance piece should be required for the seal - it is a simple press fit, to be positioned as required…
Frank
xj6 85 Sov Europe (UK/NZ)
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No Frank…
The outer race is an interference fit.
The original spacer ring is a loose fit.
The lip seal is an interference fit, exactly the same as the original felt seal housing.
It’s not the whimsy housing that holds the race in place…
The spacer is there so that the felt seal housing will not interfere with the inner race that extends further out.
The extra spacer assures that the seal sits straight.
Aristides,
I purchased my first Series III XJ6 parts car about 12 years ago when I needed some parts for the repaint of my 1984 XJ6 Vanden Plas. The car I bought from a junkyard for about $500 US was a non-running 1985 XJ6 Vanden Plas. I didn’t get any history on the car, so I didn’t know why it was junked, but that really didn’t matter to me because it had the parts I needed for the repaint and a lot of additional spare parts for me as well.
When I started the disassembly of it’s 4.2L XK engine, I removed the cam shaft covers and observed that the cam shaft on the intake side had “INTAKE” written on it in and the cam shaft on the exhaust side had “EXHAUST” written on it. The only problem was the cam shafts were swapped and the one that was painted with “INTAKE” was really the exhaust cam shaft and the one painted with “EXHAUST” was really the intake cam shaft. I soon discovered that whoever worked on this engine bent two valves due to the inadvertent cam shaft swap because of the mislabeling and that is most likely the reason that the car was junked.
I installed that cylinder head on my 1969 E-Type about 10 years ago after I replaced the two bent valves myself and it still runs nicely in that car. I have that engine block in storage in my garage as a possible spare for the future as it is very likely that the only thing wrong was the swapped cam shafts and bent valves.
Paul
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Thank you, Aristides…
Frank
xj6 85 Sov Europe (UK/NZ)
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Pinion Preload Update
You may remember from the previous posts that I adjusted the pinion preload with the hope that it would eliminate a very faint whine on deceleration.
The whine on deceleration went away but instead I had the same faint whine on acceleration…
The black line, is the original position.
I loosened the nut back, but not all the way, and found the sweet spot, the whine on deceleration is almost inaudible and no noise on acceleration.
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Road Test
Everything is silent, the “clungs” from the rear on bumpy roads are gone, no play on the wheels, the rear is now dry and brakes / handbrake all work very well.
With new steering bushes and now properly aligned the car feels very well composed and straight.
I am very happy with the result.
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Thanks to Dick_Maury, Frank, AndyBlakey, Robin O’Connor, DouglasBuchan, NWG, MattFurness and all for their valuable advise.
Aristides
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Hi,
What is that scoop like heat shield between the exhaust aft of trans pan? Mini photon-torpedo launcher?
1 Like
All that fine work and the brakes were not upgraded to vented rotors? Clearly I have not been effective in explaining the reasons for that upgrade.
Or, someone just doesn’t want to drive it that hard?
Nooo, the oil from the diff doesn’t make it on the discs but goes through the vent channels! I don’t have leaks there so I wouldn’t go through the trouble, maybe on a full brake-seal-bushing-bearing job… maybe.
Has nothing to do with driving hard. And it’s about preventing leaks.