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Re: Removing wheel bearings from hub

Posted: Sun Oct 10, 2010 5:52 pm
by BitMoreBlurred
I was talking to a mechanic friend of mine and he suggested we had a quick look. The front wheels were on the ground, we removed the hub cap and the little cover over the hub nut. When we pulled the wheel, we could see that there was play in the bearings.

I then got out the other front wheel bearing kit that I bought at the same time as the fitted wheel bearings and there was play between the inner and outer races of both wheel bearings. Surely, if there is play in the brand new wheel bearings, then there will be play when the bearings are fitted.

Has anybody else heard of this problem? Are the wheel bearings at fault?

Re: Removing wheel bearings from hub

Posted: Sun Oct 10, 2010 10:09 pm
by les
The mechanics of the complete assembly ensure there is no play. the bearings are thrust, and together with the spacer and shoulders in the hub being specific dimensions the inner race is 'pushed' into the outer race( ball bearings in between of course!) giving a specific running clearance. Now, as previously mentioned if spacer or hub shoulders are not dimentionally right the inner race could be 'held' away from the outer race slightly, allowing play. I can't see how you can detect play in the bearings before assembly, unless they are not thrust bearings.

Re: Removing wheel bearings from hub

Posted: Sun Oct 10, 2010 11:30 pm
by bmcecosse
How could he see 'play' on new bearings that weren't installed ? The bearings are assembled into the hub with the thrust directions opposing - with the correct spacer fitted - there will be NO play. Just a running clearance.

Re: Removing wheel bearings from hub

Posted: Mon Oct 11, 2010 8:51 am
by BitMoreBlurred
Thanks for the clarification. I think that the confusion came about because I did not fully understand exactly how the hub, spacer and thrust bearings work together. I'm learning all this as I go along.

Now I'm starting to doubt myself. Just to make absolutely sure I have the bearings on the correct way, can somebody tell me which way round they go?

Re: Removing wheel bearings from hub

Posted: Sun Oct 17, 2010 12:07 pm
by BitMoreBlurred
It's the weekend and I'm back on the car, trying to find out why there is play in the front hub. First thing to rule out - are the bearings the right way round?

The wider part of the inner race of both bearings is visible when the bearings are in the hub assembly. Is this the correct way round?

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Re: Removing wheel bearings from hub

Posted: Sun Oct 17, 2010 8:54 pm
by bmcecosse
Would need to see the bearings to determine the thrust direction - they should be opposing each other. And of course the centre spacer needs to be the correct thickness - but your 'mechanic' knows all this already I'm sure........ :-?

Re: Removing wheel bearings from hub

Posted: Mon Oct 18, 2010 9:08 am
by BitMoreBlurred
I spent the evening with my mechanic friend. We are sure that the bearings are in the right way round. We went over everything again. The conclusion is that the bearings are sound but there may be a small amount of wear, perhaps on the hub shoulders, that is giving a small amount of play.

My mechanic friend is currently an MoT tester and having seen the hub assembly and knowing that the bearings are new, he is satisfied that the hub assembly is safe to use. (Of course, the bearings may wear out faster than normal). Anyway, MoT is due and guess who I'm going to ask to do the test :wink:

In the meantime, I will keep my eye out for another front hub and at some time in the future swap the hubs over to test the theory.

Thanks for all the help advice - I've learnt a lot on this job.

Re: Removing wheel bearings from hub

Posted: Mon Oct 18, 2010 10:05 am
by bmcecosse
Thinning the centre spacer should remove the play.