Hub bearings

Davedstone

Member
I have severe N/S/F and O/S/R wheel bearing noise/rumble. I can see removing the front hub is straight forward, but reading the overhaul manual for the rear, the hub is removed along with the drive shaft? Is this necessary? Can I just remove the bearing housing from the De Dion elbow?
Also they mention about a collapsible spacer for rear hub bearing. Surly the existing one that is fitted should still be serviceable as it's only purpose is to achieve the correct loading on the bearings, as per the assembling with new bearings. Also looking at replacement front and rear hub bearings. Some come with this collapsible spacer, some without which makes me think it may not be required if the original was set up correctly in the first instance.
Anyone replaced rear hub bearings without having to replace this part.
Thanking anyone in advance for any advice/technical help.
Regards, David
 
The whole point of the spacer and the rear bearings, and the correct adjustment of front hub end float is that for tapered roller bearings the correct clearances at running temperature are critical to extending their lives. New bearings will ALWAYS be different from the old - in fact the manual covers re-assembly with old and new bearings - different settings. The P2,p3, maybe P4 all had 52 step vernier adjustments on their front hub nuts to enable correct setting of the end float- manuals recommended checking with a dial indicator - IIRC, .003-.005". Note that most raillway lines have little boxes on each side, at axle height - these sense hot axles (caused by imminent bearing failure) going past and somehow warn somebody to check for problems.
 
The whole point of the spacer and the rear bearings, and the correct adjustment of front hub end float is that for tapered roller bearings the correct clearances at running temperature are critical to extending their lives. New bearings will ALWAYS be different from the old - in fact the manual covers re-assembly with old and new bearings - different settings. The P2,p3, maybe P4 all had 52 step vernier adjustments on their front hub nuts to enable correct setting of the end float- manuals recommended checking with a dial indicator - IIRC, .003-.005". Note that most raillway lines have little boxes on each side, at axle height - these sense hot axles (caused by imminent bearing failure) going past and somehow warn somebody to check for problems.

Thanks for the very technical write up. Both front and rear hub bearings are standard roller bearings, not tapered as far I know. Of course the correct loading is important, but not crucial as wheel bearings have an operating temperature spread already built in with the manufacturing of the bearings suited for the application, not just wheel bearings. I will be guided by the spec in the service manual. In fact, I will remove front and rear hubs and take them to one of the garages I know who's Farther use to work on Rover P5 and P6's.
 
Hi, @SydneyRoverP6B Gives a masterclass on why you need the collapsible spacer here -

Functionality of the Collapsible Spacer

Colin
Brilliantly written.
I must admit, I got a little lost. My only question would be; Why didn't other motor manufactures use the same principle adopting the collapsible tube. The Rover 2000-2200 Repair Operation manual page 6K "Rear hub, rebuild" write about a pull of 5 to 10 lb (2,2 to 4,5 kg) is registered on a spring balance, which to me does not exactly inspire precision because the end float should be approximately 0.60 in (1,5 mm)
Am I missing something here?
 
The collapsible tubes are not uncommon - US Dana diffs use them , have done for many years. In the section you quote above, there is more to go - that is for the case of re-using old bearings - tighten nut until spacer is just trapped (end float .060), THEN TIGHTEN Further and check load required to rotate the hub. At least thats whats in the V8 book, and I doubt the 2000 is different here.
Other makers who dont use tapered rollers obviously dont need spacers, like BMC and their angular ball race rear hubs. Not at all relevant in most live axle cars. Porsche use a single large double row ball race in the rear hubs- significant work involved in pressing old out and new in.
 
The collapsible tubes are not uncommon - US Dana diffs use them , have done for many years. In the section you quote above, there is more to go - that is for the case of re-using old bearings - tighten nut until spacer is just trapped (end float .060), THEN TIGHTEN Further and check load required to rotate the hub. At least thats whats in the V8 book, and I doubt the 2000 is different here.
Other makers who don't use tapered rollers obviously dont need spacers, like BMC and their angular ball race rear hubs. Not at all relevant in most live axle cars. Porsche use a single large double row ball race in the rear hubs- significant work involved in pressing old out and new in.
Thank you for your reply and apologies for my late reply. My bearings are very notchy and rubble a lot. Loud drone which increases with speed. It is the front N/S and rear O/S and wonder if the collapsible tube is required? Have you ever changed rear bearings and replaced the tube? or when set up correctly in the first instance, then after many miles, wear obviously happens which would create a greater distance, then the difference is adjusted for? I am going to order a set for the front and rear and if the collapsible tube is out of spec, then I will order one.
 
Thank you for your reply and apologies for my late reply. My bearings are very notchy and rubble a lot. Loud drone which increases with speed. It is the front N/S and rear O/S and wonder if the collapsible tube is required? Have you ever changed rear bearings and replaced the tube? or when set up correctly in the first instance, then after many miles, wear obviously happens which would create a greater distance, then the difference is adjusted for? I am going to order a set for the front and rear and if the collapsible tube is out of spec, then I will order one.

Hi David,

Replacement front bearings are available. Modern Timken bearings come as a cup and cone pair, but they do not supply the oil seals. In such a case you will need to source these separately, alternatively you could try and find a NOS set that will include the oil seals.

For the rear bearings, you must replace the collapsible spacer otherwise their longevity is severely compromised. Genuine hub bearings kits either come with or without the spacer. If it is not supplied, you will need to source one elsewhere.

I have changed the rear hub bearings and the collapsible spacer is compressed during the reassembly process. Once this is done, they are not adjusted again. Compressing the spacer to the point of permanent deformation ensures that bearings receive the correct amount of end float, which can be measured by the tangential force required for rotation. This is the reason for using the spring balance. You don't use the initial force that is required to commence rotation, rather you use the constant force that maintains rotation.

Ron.
 
We always reused the spacer by putting it on mandrel of the right diameter and then tapping the bulge out. The only tricky bit was you needed to make sure the two ends ended up square to each other.

Yours
Vern
 
We always reused the spacer by putting it on mandrel of the right diameter and then tapping the bulge out. The only tricky bit was you needed to make sure the two ends ended up square to each other.

Yours
Vern

Hi Vern,

The downside of that practice is it introduces strain hardening of the section that had undergone plastic deformation. The spacer now has an increased risk of cracking when reused. The only way to satisfactorily reuse it is for the spacer to be annealed which returns the original degree of homogeneity and ductility by removing lattice dislocations.

Ron.
 
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