Front hubs and wheel bearings

[jaguar68]

Hi Chaps,

what is the likelihood of the front wheel bearings and seal being left on the stub axle when trying to remove the hub?

Neither the Haynes manual or the BMC manual detail how to remove the bearings from the hub. Should the bearing spacer be a floating fit inside the hub, allowing the rear bearing to be driven out of the hub?

Any advice gratefully received.

Cheers

John

[bmcecosse]

Never had them left behind - and yes - the spacer is loose and the back bearing would be tapped out of the hub - if it hadn't been left behind...... Has the bearing fallen apart? Outer left in the hub and inner left on the stub?

[jaguar68]

Hi Roy, yes the bearing has collapsed, I managed to get the inner race off of the stub axle, eventually. I'm thinking if one side of the car is bad, then the other is likely to be the same.

[bmcecosse]

Sounds like the bearing was in wrong way round......

[IslipMinor]

John,

It is quite common for the inner bearing to 'come apart', the inner race is often a bit tight on the stub axle and the angular contact bearing 'pops' apart as you pull the hub off, but it is not necessarily a problem. Why have you removed the hub? Was there play in the bearings?

I would guess that the oil seal will have been damaged slightly (or more) as it was pushed out by the inner bearing race? To remove the inner bearing outer race, clean out the grease from inside the hub and you will see 2 grooves in the hub that allow you to use a long punch or drift to tap the race out. Use equal taps on each side to remove it.

If you are planning to replace the bearing and oil seal, use the same technique to remove the outer bearing, by drifting the outer race out of the hub - the bearing should come out complete.

If the inner bearing cage is undamaged (it is usually OK), you can clean the bearing parts spotlessly and reassemble it, but unless they are fairly new, it would probably be a good opportunity to replace them.

When you come to replace the bearings in the hub, don't forget that they MUST go in the right way round from each side. Some bearings are marked with 'Thrust' on one side, which will also have the manufacturer's name and part number as well - this side goes towards the spacer, so that the two 'Thrust' sides are facing each other.

The picture below shows the 'Thrust' side of the bearings in the top row (the outer race is 'thicker') and the second picture shows the assembly:
[frame][/frame]
[frame][/frame]

[jaguar68]

Hi Richard, Roy,

the hub was removed to allow the bushes on the kingpins to be replaced and the kingpins repainted etc. However, when replacing the hub, the front bearing was pushed out of the hub, then, when the hub was removed again the rear bearing collapsed. I guess its my own fault, but at least it gives me the opportunity to clean the hubs and replace the seals and bearings.

John

[bmcecosse]

Check for any damage/burs/chisel marks on the stub axle - my front hubs have always just 'slid off' complete, with a hand tug.

[sixdogsisback]

John,
I know this is an old thread, but I've been searching for information on fitting the front wheel bearings. I had to remove the hub to remove the trunnions and the inner bearing came to pieces leaving the inner race on the stub axle. The official BMC Manuel which I have tells me very little, though it's handy to stand on to change a light bulb in the house! When the hub came away, it scattered the components on the garage floor so I have no way of telling which way the spacer goes or the bearings. Looking at your colorful drawing, I still cannot see where the oil seal and spacer fit for certain. Can you explain in words?
Luckily, I have a new packaged wheel bearing kit with seal but now with all the talk about inferior kits, I'm wondering if I have one of these which is best avoided. How can I tell? What can happen to these inferior bearings?

Thanks, Clive

It is quite common for the inner bearing to 'come apart', the inner race is often a bit tight on the stub axle and the angular contact bearing 'pops' apart as you pull the hub off, but it is not necessarily a problem. Why have you removed the hub? Was there play in the bearings?

I would guess that the oil seal will have been damaged slightly (or more) as it was pushed out by the inner bearing race? To remove the inner bearing outer race, clean out the grease from inside the hub and you will see 2 grooves in the hub that allow you to use a long punch or drift to tap the race out. Use equal taps on each side to remove it.

If you are planning to replace the bearing and oil seal, use the same technique to remove the outer bearing, by drifting the outer race out of the hub - the bearing should come out complete.

If the inner bearing cage is undamaged (it is usually OK), you can clean the bearing parts spotlessly and reassemble it, but unless they are fairly new, it would probably be a good opportunity to replace them.

When you come to replace the bearings in the hub, don't forget that they MUST go in the right way round from each side. Some bearings are marked with 'Thrust' on one side, which will also have the manufacturer's name and part number as well - this side goes towards the spacer, so that the two 'Thrust' sides are facing each other.

The picture below shows the 'Thrust' side of the bearings in the top row (the outer race is 'thicker') and the second picture shows the assembly:
[frame][/frame]
[frame][/frame]

[IslipMinor]

Clive,

The oil seal is the 'yellow' part on the left side of the diagram and is fitted with its 'open' side towards the inside of the hub. The spacer is the 'grey' part in between the bearing in the diagram and is fitted with the larger diameter against the inner bearing, but can it actually be fitted the wrong way round?

[sixdogsisback]

No, now that I've rebuilt the hub a couple of times, it is obvious how the spacer fits and which bearings are inner and out as they are different sized and can only be fitted one way. On examining the bearings they are marked "thrust" side. The difficulty now, if you are following the thread I started on swivel pins and trunnions, is that the new bearings would not go on the stub axle. I wrecked a set of bearings trying to force then on. Once you get them fast. they disintegrate when you try to get them back off. they are designed to stand sideways pressure in one direction only. I ended up filing and emery clothing the axles to get the bearings to fit them. I know you should not do this but it is obvious that the axles are machined too large a diameter, when I offered the bearings to the old swivel pin axles, once they had been cleaned up, the bearings were just a nice firm push fit. I think it pays to make sure that the bearings are going to fit the axle before assembling the hub, as if the hub won't drive home with reasonable force, the inner bearing will be wrecked if you lever the hub back off.

Thanks for the reply. Clive.

[svenedin]

I know this is an old thread but like the original poster I have been unable to find any information on how to get the bearings out of the hub. Various books I have helpfully instruct the reader to ensure that the bearings are the right way round when reinstalling but neglect to mention how to get the bearings out in the first place!

I can't see the grooves that are referred to in this thread so I cannot work out how to go about getting the front and rear bearings out. It is suggested in the thread that a long punch can be passed in these grooves but they don't seem to exist in my hub. I can see that the front bearing seats up against a machined lip in the hub which suggests it cannot come out forward. The rear bearing could pop out backwards (after the oil seal has come out) but again I am at a loss to know how to do it. Is the oil seal levered out with a screwdriver first?

[ssnjimb]

Part of the inner bearing on my midget had welded its self to the stub axle because the garage that changed my wheel bearings in the past did not bother to grease them, so they overheated and when i went to remove them they fell apart

I have changed both stub axles,

Jamie

[mike.perry]

The oversized stub axle seems to be a common problem. I could not fit the bearing assembly on the last n/s swivel pin which I had bought (my Series MM hubs hav been modified to fit M1000 swivel pins) I checked the bearings on a couple of old stub axles and they fitted fine but not on the new stub axle.

[sixdogsisback]

Yes, this is exactly what I found. So what is the answer? take the new swivel pins and axles back to the supplier? I've bought a micrometer since I had the problem.
Clive

[sixdogsisback]

Further thoughts, it was the nearside on my car which had the problem. The offside was no problem. I wonder if they are all like that?
Clive

[svenedin]

Can anyone tell me how to get the bearings out of the hub?

[ssnjimb]

if your not using them again a flat screwdriver and a hammer

Jamie

[svenedin]

I will be using them again. I just need to give them a thorough clean. I have a new oil seal to put back.

[bmcecosse]

I've already suggested to you that you should leave them in place - by all means lever out the old oil seal and then wash the old bearings in the hub - and then regrease, and fit a new oil seal. Removal of the bearings involves a long/thin punch and great care - you will clean them perfectly well without removal which saves all the risks of damage!

[svenedin]

Sorry I must have missed that. Yes that sounds much better. I just need to be able to clear out the back bearing and the oil seal needs to come out for that. I was unsure whether it could be levered out on its own. I can clean out the front bearing already. Brake back plates are being chemically de-rusted in a bucket prior to painting. The are coming up very well. It will be so much easier to bend the new brake pipes neatly with the backplate assembly on the bench rather than still on the car. I really hate putting back grotty parts when I have gone to the trouble to take it all apart. It just seems sloppy not to service and refurbish as I go along because I do have pretty much as long as I like to do this.