Greasing Inner Wheel Bearings

[4 Strings]

I have an S210 from 2000. Seems to suffer from the 'is it wheel bearings or is it tyre noise' at the front. I'm pretty convinced it's wheel bearings as it's a sort of rolling drone over 50mph, especially on quiet road surfaces. It's a lovely quiet car and so noises are noticeable, but also, I'd like to get it as quiet as it was designed.

I therefore had a look and there was a little play and the outer bearings and they were completely dry. I repacked with multi-purpose grease and reset the adjustment on them but not sure anything is any better. I'll give it another go as I have now bought the proper MB grease and so will clean and repack the outers but also I would like to repack the inner bearings (can see no reason why they shouldn't be as dry).

Is there any way of doing this without taking the calipers off? If I do have to take them off, should I replace the bolts or are they ok to reuse?

The car has done 100,000 miles and I'll probably need to renew the discs in the next couple of years.

 

[grober]

To access/inspect/grease the inner wheel bearings you will need to remove the hub/disc. You will have to remove the calipers. If the caliper bolts are in good nick they can be reused but use some locktight on the threads
http://www.pelicanparts.com/techart...33-SUSPEN-Front_Wheel_Bearing_Replacement.htm

 

[Bellow]

If the bearings have been run dry they are likely scrap.
Unless they are entirely free of any form of marking (including heat) bin them and renew. Otherwise, you are merely wasting your own time.

 

[Auto-mobile]

Have you checked your tyres?

 

[4 Strings]

Thanks for the replies.
After I posted this, I sat there thinking and realised it would be impossible to replace the seal without removing the hub anyway!
I'll need to get another seal so I suppose I may as well get the bolts too.

Despite being dry, the outers looked perfectly ok once I'd cleaned them up although what grease was there was pretty black. Hopefully the inners will be ok too, only one way to find out.

As I don't really have the tools to remove/replace the conical surfaces, I'm wondering about simply buying the whole hub with bearings. Do you think I'd be wasting my time just renewing the rollers and not the surfaces? Feel that the worn surfaces may not mate precisely with new rollers.

I believe the tyres are noisy too, noise changes dramatically with road surface but what should I actually check? The tread is ok (not vee form), pressures at 30psi. They won't last forever and I'm looking forward to replacing them with something hopefully quieter. I've not swapped them with the rears to see if that helps.

 

[Bellow]

The black in the grease will be the moly.
If there's no pitting or particularly, no detectable (by finger nail) grooves then the race may be OK. In which case re use the rollers (as they also can be considered to have survived). New rollers in old races isn't going to do much for you.

 

[4 Strings]

Thanks, the outer races both looked fine, smooth and shiny.

I'll have to look at the inner races as I can't really rest until I know what they look like and are wallowing happily in green grease! To do so, I'll need to go shopping for the seals and caliper bolts.

 

[Bellow]

Take care to ether use the same thickener base grease (lithium, lithium complex, aluminium complex, etc) or be sure to clean all the old grease out.

 

[4 Strings]

Take care to ether use the same thickener base grease (lithium, lithium complex, aluminium complex, etc) or be sure to clean all the old grease out.

Yep, thanks. I have bought the proper MB green grease and I will be cleaning every morsel of what's in it at the moment out.

Is there a problem with two different types, does it go lumpy or something? (In which case I might be better of buying new bearings,even if I just use the new rollers)

 

[t-dawg1]

Just buy new bearings mate,they cheap on the Mister Auto website Febi Bilstein ones. I bought the whole hub for mine comes ready packed for under £100

 

[Bellow]

Yep, thanks. I have bought the proper MB green grease and I will be cleaning every morsel of what's in it at the moment out.

It's near impossible to know what others have applied in the past so getting riid of it is a good move.

Is there a problem with two different types, does it go lumpy or something? (In which case I might be better of buying new bearings,even if I just use the new rollers)

The other way. Dissimilar thickener bases can clash and when they do they thin and run out. Lithium and lithium complex (the two types you are most likely to encounter) are compatible though.

 

[4 Strings]

Just buy new bearings mate,they cheap on the Mister Auto website Febi Bilstein ones. I bought the whole hub for mine comes ready packed for under £100

Well, I think it might be coming to that, although not sure I want to stretch to £200 buying two whole hubs, although that should finish things.

I just had a quick look at one side today (in the hope of doing the regrease job but I didn't have an 18mm socket for the calipers- 17, 19, yes!) and while the races are indeed pristine, the rollers are showing bits of blue from past overheating, probably from long runs on the dry bearings. Juiced them up again.

If I buy just a bearing set, is there likely to be a problem just replacing the rollers without the races? Or will it be new wine in old skins?

 

[4 Strings]

It's near impossible to know what others have applied in the past so getting riid of it is a good move.



The other way. Dissimilar thickener bases can clash and when they do they thin and run out. Lithium and lithium complex (the two types you are most likely to encounter) are compatible though.

Thanks, makes me feel easier. I'll be cleaning out thoroughly too though.

 

[Bellow]

and while the races are indeed pristine, the rollers are showing bits of blue from past overheating, probably from long runs on the dry bearings. Juiced them up again.

The races must have seen the same friction (and heat) that blued the rollers. I'm just surprised there is no sign of wear.

If I buy just a bearing set, is there likely to be a problem just replacing the rollers without the races? Or will it be new wine in old skins?

Are rollers (and cage) available separately? If so, and you don't grudge the time spent trying, you could fit the rollers, monitor, and be ready to change entire bearings if it doesn't work out.
The worry is that if wear has occurred on the races the thin layer of 'case hardening' will be depleted. Once that happens, the load of the rollers can deform the case and while the hard case springs back, the softer underlying metal is permanently deformed. When this occurs, the case lacks support and will in time fail. Likely as not, the failure will be quick and substantial.

 

[hotrodder]

You don't normally need special tools to replace the races. Never had a front hub off of a 210 but there's usually notches inside hubs to make life easier drifting the old races out. New ones can be tapped in using a suitably sized socket or the old race to avoid damaging it/help keep it 'square'... putting the new races in the freezer before starting the job helps as they'll shrink a tiny bit i.e. less of an interference fit until they warm up again
As an aside another trick for removing the outer race of stubborn bearings is a welder. Welds shrink as they cool, run a bead of weld around the remains of the bearing and it'll fall out as it cools. Overkill/unecessary for front hubs with tapper needle bearings but usuefull with some one piece bearings that are a much tighter press fit

If the inner race is properly stuck/seized to the stub axle and you haven't got a puller then an angle grinder is typically the fastest/easiest way... grind most of the way through the race in one spot (when it gets close it'll 'blue' locally from the heat) and then clobber it with a cold chisel. It'll crack and if it doesn't fall off by itself it'll be easy to pry off

As Bellow it's not a good idea to reuse old races. The tolerances on things like bearing surfaces are insanely tight i.e. looking/feeling smooth doesn't mean they're OK, just that they aren't totally FUBARed. The rollers are much smaller than their races and aren't in contact with the hub & stub axle which acts as a heat sink i.e. damage to them is often more noticable

All of that said if the hubs, specifically their disc mounting surface, are looking manky/rusty then new hubs starts to make more sense. Especially if the discs are nearing the end of their life as manky hubs are a common cause of the legendary "warped discs" myth... what actually happens is excessive disc run out results in uneven wear of the new disc and it's this thickness variation that causes the judder

 

[4 Strings]

I've also looked at a few Youtubes of this process. Replacing the races looks pretty possible if patience and time is available. I suppose if all goes wrong I could simply bin the whole thing and buy new hub(s). I'll have to try and find a period when I can get away without the car for a week should that happen.

The grease seals alone were £24 a side from Mercedes (rather blowing my impression of MB for reasonably priced spares). The whole bearing set with seal is about that from elsewhere. Any recommendations in the outside world for good sources/manufactures or those to avoid?

 

[RichardF]

I'd use MB seals, for the sake of £24 you know what you're getting.

 

[BlackC55]

What make tyres do you have?

Are they "feathered"?

 

[OneForTheRoad]

id of bought the whole MB hub and simply fit it, I tried the cheap fix and had all kinds of abs ,power steering problems , ebs , faults . good luck on trying though.

 

[4 Strings]

id of bought the whole MB hub and simply fit it, I tried the cheap fix and had all kinds of abs ,power steering problems , ebs , faults . good luck on trying though.

ha, yes, very good argument! Maybe I'm just too much of a tight-wad to splash out on whole hubs unless I really need to, however, you're right, risk of plenty of other problems arising.