Front wheel bearings

[RoSPA_man]

Hi all

About to tackle a new job- refurbishing my spare front wheel. I gather that if I get them powder coated or 2 packed, I will probably need to take out (and realistically) replace the bearings.

 

Any bearing advice, e.g tips to take them out and to refit. I imagine heat is required to the wheel part for extraction and for refit, freezing the bearing while heating the wheel. How will the new finish hold up to heat etc etc. What tools are needed to remove the bearings and what should I use as a drift to refit - the old bearings perhaps?

All advice gratefully received!

 

[dirtrider]

Afternoon Hugh

 

Unfortunately about the only way to get those bearings out is driving on the inner race but the bearing is held into the wheel around the outer race. When doing that there is always the chance of pitting or brinelling the races where the balls contact the races during driving.

SO, the smart thing to do is just replace the bearing after removal.

 

To remove—sometimes you can move the inner spacer over enough to get a long drift in on the opposite bearing center and drive it out. On a lot of the BMW wheels that spacer is such a tight fit you just can’t move it far enough to get a bite on the opposite bearing. What I use is a short bolt that just fits the bearing bore, I take a grinder (or even a hacksaw) and cut a slit in the bolt with a V notch near the end. Then insert the bolt into a wheel bearing and lay the bolt head on something hard, then reach in from the other side (through the bearing center) with a large screwdriver or narrow chisel and insert it in that bolt slot. Then rap the screwdriver a couple of times to drive it into the bolt slot. That will expand the bolt into the bearing center. Then remove the wheel including bolt from the hard surface. Then give that screwdriver a couple of firm hits with a hammer (that usually drives the bearing right out. From there it is a simple matter to drive the other bearing out after the center spacer is removed.

 

You could heat the wheel if you want as that would make the bearing come out easier but I never have found a need to.

 

 

[mxharris]

dirtrider

Your smart, I bought the motion pro kit. Same idea but your way is $60 cheaper!

[RoSPA_man]

Afternoon Hugh

 

Unfortunately about the only way to get those bearings out is driving on the inner race but the bearing is held into the wheel around the outer race. When doing that there is always the chance of pitting or brinelling the races where the balls contact the races during driving.

SO, the smart thing to do is just replace the bearing after removal.

 

To remove—sometimes you can move the inner spacer over enough to get a long drift in on the opposite bearing center and drive it out. On a lot of the BMW wheels that spacer is such a tight fit you just can’t move it far enough to get a bite on the opposite bearing. What I use is a short bolt that just fits the bearing bore, I take a grinder (or even a hacksaw) and cut a slit in the bolt with a V notch near the end. Then insert the bolt into a wheel bearing and lay the bolt head on something hard, then reach in from the other side (through the bearing center) with a large screwdriver or narrow chisel and insert it in that bolt slot. Then rap the screwdriver a couple of times to drive it into the bolt slot. That will expand the bolt into the bearing center. Then remove the wheel including bolt from the hard surface. Then give that screwdriver a couple of firm hits with a hammer (that usually drives the bearing right out. From there it is a simple matter to drive the other bearing out after the center spacer is removed.

 

You could heat the wheel if you want as that would make the bearing come out easier but I never have found a need to.

 

 

I took the easy route and while having a bent rim repaired (prior to powder coating), I asked the guy to knock out the bearings which he did FOC. Now I need to put in the new ones. I have to hand a domestic freezer, new bearings, seals, the old bearings, a 34 and 36mm socket, one of which sits perfectly on the outer shell of the bearing. I intend to heat the wheel on our Aga, freeze the bearings, use the old bearings or the socket and a rubber hammer to tap in the new ones. Anything I should be especially careful of doing/not doing? Should I apply any lubricant to the bearing to help with insertion etc...

[dirtrider]

Morning Hugh

 

It isn’t rocket science. I just heat the wheel hub to around 175°f (careful of the wheel paint) then drop the washer & bearing in and dive it home using the old bearing outer race. (either grind the old inner bearing race shorter or remove it completely so you don’t accidently drive on the new bearing center).

A socket will also work, just make sure it sits on the outer race only & not the seal or inner hub.

 

 

 

 

 

[RoSPA_man]

Morning Hugh

 

It isn’t rocket science. I just heat the wheel hub to around 175°f (careful of the wheel paint) then drop the washer & bearing in and dive it home using the old bearing outer race. (either grind the old inner bearing race shorter or remove it completely so you don’t accidently drive on the new bearing center).

A socket will also work, just make sure it sits on the outer race only & not the seal or inner hub.

 

Morning DirtRider

Yet again, your input's been really useful. The socket is a perfect fit in the wheel centre, but there was a possibility the inner bit might have made contact with the seal part. So I've just had my evening's entertainment knocking out the centre of the old bearing with some old-fashioned brute force and ignorance, ready to use on the new bearing install. I'm happier doing it that way. On the lubing front, is it needed on the new bearing outer face to ease it in, does it help or is it a no-no?

[dirtrider]

Afternoon Again Hugh

 

The BMW manual doesn’t mention lubricating the bearing outer before installation (probably because of the heat on the hub).

 

Personally I don’t but see a reason not to. I do however (lightly) lubricate the OD and ID of the center spacer but the manual doesn’t request this either.

 

One thing I should caution you on: when you drive the 2nd bearing in go back and make sure it didn’t dislodge the first bearing if the spacer cocked a little when driving the 2nd one in.

 

[RoSPA_man]

Morning Hugh

 

It isn’t rocket science. I just heat the wheel hub to around 175°f (careful of the wheel paint) then drop the washer & bearing in and dive it home using the old bearing outer race. (either grind the old inner bearing race shorter or remove it completely so you don’t accidently drive on the new bearing center).

A socket will also work, just make sure it sits on the outer race only & not the seal or inner hub.

 

 

I think I must be jinxed - I fitted the bearings. It may not be rocket science but it still went wrong! I thought I did it all by the book - with apparently no problems - and now they do not turn at all on either side!! I used the old outer bearing as the drift.

 

However, I did position the socket between the bench and the installed left side bearing to avoid unseating it while I tapped in the right bearing from above. This may have squeezed everything together too tightly? It does also look as if I slightly made contact with the rubber seal slightly- aaagggh! 2 lessons learnt!

 

I can only assume that it is the case that the centre of the bearings are jammed to the spacer.

 

Is it possible to bang these bearings in too far? I assumed that I should bang them in until they hit the internal shoulder...

 

Ah well, at least they are not expensive - I see them on Ebay (FAG 6205 2RSR -c3) at £5 each which is where I will get my next set and not at $20+ from BMW parts suppliers!

[mistral]

Morning Hugh

 

It isn’t rocket science. I just heat the wheel hub to around 175°f (careful of the wheel paint) then drop the washer & bearing in and dive it home using the old bearing outer race. (either grind the old inner bearing race shorter or remove it completely so you don’t accidently drive on the new bearing center).

A socket will also work, just make sure it sits on the outer race only & not the seal or inner hub.

 

 

I think I must be jinxed - I fitted the bearings. It may not be rocket science but it still went wrong! I thought I did it all by the book - with apparently no problems - and now they do not turn at all on either side!! I used the old outer bearing as the drift.

 

However, I did position the socket between the bench and the installed left side bearing to avoid unseating it while I tapped in the right bearing from above. This may have squeezed everything together too tightly? It does also look as if I slightly made contact with the rubber seal slightly- aaagggh! 2 lessons learnt!

 

I can only assume that it is the case that the centre of the bearings are jammed to the spacer.

 

Is it possible to bang these bearings in too far? I assumed that I should bang them in until they hit the internal shoulder...

 

Ah well, at least they are not expensive - I see them on Ebay (FAG 6205 2RSR -c3) at £5 each which is where I will get my next set and not at $20+ from BMW parts suppliers!

 

I replaced my bearings awhile back. I too had the same problem. I thought you just drove them in, but the spacer made contact and the bearings were tight. I just backed off of a bearing. It was abused in doing so. I don't like it but I am just riding it. I thought you could not go in too far. Makes it kind of hard to get right.

 

Ron

[dirtrider]

Morning Hugh

 

Not sure what went wrong but before pounding those bearings back out try inserting the axle through the bearings then rapping it a couple of times on the end with a rubber or rawhide mallet (see if that loosens it slightly). The inner spacer ultimately controls the bearing spacing when you torque up the axle so if bearing seats in the wheel are just a bit close together (or grease trapped between the spacer and inner race) you could get a little binding until one or both outer races move slightly or the spacer compresses just-a-bit under axle torque.

 

Remember that you shrunk fit the wheel around the new bearings outer race so if the bearings are on the tight side they might be a bit too tight to turn with a finger tip. Maybe next try installing the axle and wheel in the forks (no bakes or fender break), then giving it a spin.

 

If the wheel can be spun when installed just spin it for a while then remove the wheel, then re-check the bearings for being a bit looser.

 

You shouldn’t be able to seat those bearings any farther than the stepped seats in the wheel hub so unless the bearings are not correct or the spacer is burred on the end they should be in the correct position.

 

 

 

[Selden]

Now I need to put in the new ones. I have to hand a domestic freezer, new bearings, seals, the old bearings, a 34 and 36mm socket, one of which sits perfectly on the outer shell of the bearing. I intend to heat the wheel on our Aga, freeze the bearings, use the old bearings or the socket and a rubber hammer to tap in the new ones. Anything I should be especially careful of doing/not doing? Should I apply any lubricant to the bearing to help with insertion etc...

The last time I did bearings, I bought a small chunk of dry ice, which will get them a lot colder than a freezer.

[RoSPA_man]

Morning Hugh

 

Not sure what went wrong but before pounding those bearings back out try inserting the axle through the bearings then rapping it a couple of times on the end with a rubber or rawhide mallet (see if that loosens it slightly). The inner spacer ultimately controls the bearing spacing when you torque up the axle so if bearing seats in the wheel are just a bit close together (or grease trapped between the spacer and inner race) you could get a little binding until one or both outer races move slightly or the spacer compresses just-a-bit under axle torque.

 

Remember that you shrunk fit the wheel around the new bearings outer race so if the bearings are on the tight side they might be a bit too tight to turn with a finger tip. Maybe next try installing the axle and wheel in the forks (no bakes or fender break), then giving it a spin.

 

If the wheel can be spun when installed just spin it for a while then remove the wheel, then re-check the bearings for being a bit looser.

 

You shouldn’t be able to seat those bearings any farther than the stepped seats in the wheel hub so unless the bearings are not correct or the spacer is burred on the end they should be in the correct position.

 

Yep! Correct again! I did what you said and it worked. Spins fine with no notchiness at all etc. It's wheel only at this point but even with that light weight, I got it to turn lots of revolutions. When I removed it, it was still not possible to turn with fingers, but now I guess that's a good thing!

Many thanks for the tips!

[deaks]

Ok, so I have the exact problem described by dirtrider. I cannot move the bearing spacer more than a mm or two. After 2 hours of banging away with a screwdriver in the vain hope of moving one of the bearings even a little, I have given up and read the forum for hints. Did you really get a bolt big enough to fit the inner race of the front bearings? Would that be about an M24?

 

Cheers,

Scott

 

On a lot of the BMW wheels that spacer is such a tight fit you just can’t move it far enough to get a bite on the opposite bearing. What I use is a short bolt that just fits the bearing bore, I take a grinder (or even a hacksaw) and cut a slit in the bolt with a V notch near the end. Then insert the bolt into a wheel bearing and lay the bolt head on something hard, then reach in from the other side (through the bearing center) with a large screwdriver or narrow chisel and insert it in that bolt slot. Then rap the screwdriver a couple of times to drive it into the bolt slot. That will expand the bolt into the bearing center. Then remove the wheel including bolt from the hard surface. Then give that screwdriver a couple of firm hits with a hammer (that usually drives the bearing right out. From there it is a simple matter to drive the other bearing out after the center spacer is removed.