Rear Hub Bearing Failure

Hi, glad to be of help. Those bearing, both of you, are quite bad and you say there was no
significant noise earlier. Do you think the bearings have not lasted as long as you think they
have, but have just not displayed the extent to which they have deteriorated? Judging by the
pattern of damage do you think (especially bjk67,s) that is a result of being stood in one
place for long periods?

I think this could be a salutary lesson for others.

Colin
 
Hi Colin,

I know in the case of mine, the bearings ran for over 238,000 Miles, and when I fitted new universal into the shaft just over 2 years and some 23,000 Miles earlier, the hub at that time felt perfectly smooth. Turning the hub slowly and feeling for the smallest irregularity didn't deliver even the slightest cause for concern, so either the damage was effectively masked, or it reached the point where failure began just after.

There are many different types of bearing failure, as these links detail. The second link is a 58 page document from Timken.
http://www.emersonbearing.com/technical-toolbox.html

http://www.nrel.gov/wind/pdfs/day2_sess ... _evans.pdf

Ron.
 
Hi, very interesting Ron. The damage to the bearings looks like corrosion, which I
now recall reading an article many years ago about oils and greases and how they
are brewed for the want of a better word. The article did say that the water content
in grease can be higher than the ideal and were OK to be used in places like front
wheel bearings where they ran hotter to keep the water content at an acceptable level.
Also that heavier oils like EP were better lubricants, which is why commercial vehicles
run oil fed hubs.

Colin
 
Indeed, grease after some time in service tends to be pushed away from the bearings which run dry and fail.
Recently, the front ones in my Rover just started to become noisy, and upon inspection the inner ones were found dry. Thankfully they were still intact, and some fresh grease made them silent running again.
I think there was a provision for a grease point in the early rear hubs, that was unfortunately deleted in the later models. Without dismantling the hub there is no means to add some fresh grease into it.
 
Are those collapsible spacers still available? I am pretty certain that they aren't available in South Africa.
What are their dimensions, I am reckon they could be turned out on a lathe or am I missing something in that idea?
 
The spacers are available from both Wins & JRW but Wins are cheaper :)

Colin, I think that you are correct with mine, having stood outside for 3 years before I got it.
 
Demetris said:
I think there was a provision for a grease point in the early rear hubs, that was unfortunately deleted in the later models. Without dismantling the hub there is no means to add some fresh grease into it.


Like this one

CIMG5345.jpg


Dave
 
Hi Dave,

Although it shows such in the workshop manual, that is the first time that I have actually seen a hub, photo or otherwise, with a grease access point. The early hub driving flanges and half shafts were not balanced like the later items, which featured drillings within the flange and small weights attached to the shafts. I wonder if that was part of the reason behind deleting the greasing point. :? It would certainly seem a possibility.

There may have also been a concern regarding the ingress of dirt and moisture, which would definitely outweigh any advantages in having such a facility.

Ron.
 
SydneyRoverP6B said:
Hi Dave,

Although it shows such in the workshop manual, that is the first time that I have actually seen a hub, photo or otherwise, with a grease access point. The early hub driving flanges and half shafts were not balanced like the later items, which featured drillings within the flange and small weights attached to the shafts. I wonder if that was part of the reason behind deleting the greasing point. :? It would certainly seem a possibility.

There may have also been a concern regarding the ingress of dirt and moisture, which would definitely outweigh any advantages in having such a facility.

Ron.


I have a pair of them that have been fitted to Lady C since I got her 4 years ago. I must admit I've not tried to remove the access caps to grease the bearings yet.

Dave
 
When I am ready to rebuild the hub, I note that the workshop manual calls for the application of Loctite onto the splines. Loctite AVV 086 is not freely available in Australia anymore, having been deleted from the Australian website, although it is still available within the United States. An alternative would be Loctite 263 which is also a high strength sealant with very similar properties.

My question though is this. Why would Loctite be recommended in place of say grease or an anti seize lubricant for the splines? The hub that I dismantled displayed rotational movement to a small degree on the splines, which was not noticably different to the NOS item that was installed in its place. The Loctite will make separation of the drive flange assembly from the hub body rather more difficult than if grease or similar was used instead, so apart from this impediment, what is the Loctite's purpose?

Ron.
 
Hi, I would think it is to stop spline 'chatter' from alternating rotational forces, grease or
similar would encourage it and the eventual destruction of two fairly large components. I
know we don't see much wear on the sliding joint of 'our' prop shafts because there is not
much displacement lengthwise, but in some applications like Land rovers it can get quite
pronounced. I have gaitors on mine and still get it, so it is not just dirt getting in.

Colin
 
Hi Colin,

That seems quite a reasonable argument. Filling the voids to as to minimise "chatter" would certainly assist in reducing wear. There were flakes of Loctite throughout the splines upon separation, and after cleaning and close inspection, I could see really no wear at all. No bright marks or anything to indicate abrasion.

Ron.
 
Sorry for kicking this topic, but I was wondering which loctite you ended up using on the splines. AVV 086 seems to be very hard to come by, I contacted Loctite to ask what they advise as an alternative. They told me to use Loctite 638, although this seems the right product based on this application, it doesn't seem similar to AVV 086 to me.
 
Between June 18 and 28 of 2017, apart from undertaking a major refurbishment of my Rover's front suspension, I also allocated time for the rebuilding of the same rear hub, as covered within this post of 2011.

IMG_1853.jpg
I tapped in the two oil seals, applied Castrol EPL-2 to the cups in turn and then placed the inner bearing onto the cup that can be seen above. It was then liberally coated with grease, ensuring that it was worked well within the cage and around all of the rollers.

IMG_1854r.jpg
The outer Timken bearing received a coating of grease. The S & G Walker collapsible spacer can be seen sitting over the shaft, seating against the bearing face. It is a snug fit, positioned by hand. The splines on the yoke shaft received an application of Loctite 609. I had wanted to use Loctite AVV 086. When I contacted Henkel, I was asked why I wanted it. On offering the reason I was then asked for specific details as to the hub and spline dimensions, and whether the hub would again need to be taken apart. I asked again if AVV 086 was still available. I was advised that it is a product that is used for military and aerospace applications, and only comes into Australia under a special order from the Federal Department of Defence :eek: So I purchased a 10ml bottle of Loctite 609 instead. It is a medium strength product, used for splines etc., to eliminate fretting corrosion, so it seemed like an excellent choice.

IMG_1857r.jpg
The hub is secured within the jaws of an offset Dawn vice. Substantial force is required to deliver the necessary axial load onto the collapsible spacer to deliver plastic deformation. The 1/2" bar attached to the socket was bending noticeably as I pulled the bar down. Indeed, I can say without hesitation that this was clearly the most force I have ever applied to anything before. :eek:

IMG_1856r.jpg
I was waiting for the bar to either snap or the socket to explode! I was wearing safety goggles just in case :eek:

IMG_1855r.jpg
A suitably sized nut was held in place with gaffer tape, to facilitate location of the spring balance. After numerous applications of force, a reading of 4 to 4.5kg was measured. The designated range as per the workshop manual is 2.2 to 4.5 kg ( 5 to 10lbs). The readings were not consistent, but fell without that range. Static friction is greater than kinetic friction, so this would account for the variations. Subsequently, I attached an imperial spring balance to the flange and a reading of 8lbs was recorded.

IMG_1866r.jpg
New universal joints were also fitted into the half shaft, using a G-clamp to press them in. No grease is used on either the yoke eyes or the cups. This method works perfectly, and is substantially better than trying to drift them in. This one a Repco brand.

IMG_1867r.jpg
Whilst this one is a U.K manufactured Hardy Spicer.

IMG_1865r.jpg
It will now sit and wait its turn for service, at some point down the line. :)

Ron.
 
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