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Damage to hub bearing faces - solutions?
jps - 17/4/18 at 09:18 AM

I stripped some old Sierra hub carriers the other day and am part way through painting them. In driving out the old outer races (using a screwdriver - presumably this was mistake number 1!) I have left some small nicks/'lumps' in the faces that the new bearings will have to go back in against.

Do I just need to dress these back with a fine file, dremel grinding stone or similar - or will the new bearing races be so much harder that when I drift them back in they will just seat down in the right place anyway?

nick205 - 17/4/18 at 09:55 AM

I'd dress the faces smooth with a file and or wet n' dry. The new bearings will need to be pressed in to get a clean straight entry.

mcerd1 - 17/4/18 at 02:00 PM

just use emery paper to take off the high points / sharp bits and not to remove any more material than you really have to

shouldn't cause any problems unless they are really badly scored

Theshed - 18/4/18 at 06:13 AM

You will be fine but do need to take care to ensure that you remove the high spots properly. It will not take much to push the race out of round - forget the idea that the race will push the hub into shape (OK so it will a tiny bit).

If the housing is badly damaged there is a special Loctite product designed specifically to restore bearing housings.

It is generally a bad idea to drift bearings in. Put the race in the deepfreeze overnight and then the hub in the oven for 30 mins. They will fall together. Then you can spend the rest of the day saying sorry and explaining that the smell of warm oil is not as bad as some say......

[Edited on 18/4/18 by Theshed]

jps - 18/4/18 at 07:41 AM

quote:
Originally posted by Theshed
Put the race in the deepfreeze overnight and then the hub in the oven for 30 mins. They will fall together.
[Edited on 18/4/18 by Theshed]


I have seen this in a few places - but really wasn't sure to what extent they will really 'fall together'. To get the old outer races out I put the hub carrier in the oven for 45 minutes at 200c and it still took me hitting a screwdriver with a club hammer to get them out!

nick205 - 18/4/18 at 08:19 AM

quote:
Originally posted by jps
quote:
Originally posted by Theshed
Put the race in the deepfreeze overnight and then the hub in the oven for 30 mins. They will fall together.
[Edited on 18/4/18 by Theshed]


I have seen this in a few places - but really wasn't sure to what extent they will really 'fall together'. To get the old outer races out I put the hub carrier in the oven for 45 minutes at 200c and it still took me hitting a screwdriver with a club hammer to get them out!



A mechanics hydraulic press is the best simplest way in my experience. I don't have one, but have a friendly garage with one and they're happy to do small jobs like this for a full biscuit tin.

Angel Acevedo - 18/4/18 at 10:49 AM

quote:
Originally posted by jps
quote:
Originally posted by Theshed
Put the race in the deepfreeze overnight and then the hub in the oven for 30 mins. They will fall together.
[Edited on 18/4/18 by Theshed]


I have seen this in a few places - but really wasn't sure to what extent they will really 'fall together'. To get the old outer races out I put the hub carrier in the oven for 45 minutes at 200c and it still took me hitting a screwdriver with a club hammer to get them out!


To use the same principle, you would need to cool the bearing race and heat the hub which is not that easy.
Getting them in is easy as you can apply heat/cold to searate pieces easily.
This same principle can be applied to drinking glasses stacked stuck.
in this situation is also easy as you can pour cold water in the glass on top and submerge the ne at the bottom in warm water.
Regards.
AA

Theshed - 18/4/18 at 11:09 AM

You are quite right it does not work for getting the little buggers apart! What can work is running a bead of mig weld around the bearing - bearing shrinks on cooling and out it pops. Clearly a press is the way to go.

Heat/cold is the answer for assembly bearings do not like hammers.....