W126 Brakes - a couple of questions - Page 3 - PeachParts Mercedes-Benz Forum

mowoc · #31 05-16-2009, 07:35 PM

Quote:

Originally Posted by Matt L

It's going to be tight. Often you can get something through a hub to punch it out from the other side. If you resort to prying it out, be sure that you don't damage the roller cage.

Also ensure that any used bearing parts are put back in service exactly as they came out. Be sure not to switch anything side-to-side (I'm pretty sure that the inner and outer bearings are different on that car).

I only saw one bearing that came out of the hub. It is a bit like a funnel (one end bigger than the other). Where is the other bearing?

Also, there is a ton of grease in that thing - do I clean it all out? I am betting that the other bearing is somewhere under that grease near the engine side of the hub, right?

I will try and pry the seal out - I think I see how it works now.

79Mercy · #32 05-16-2009, 07:35 PM

once you get the seal out you'll find the other bearing.

tangofox007 · #33 05-16-2009, 08:49 PM

Quote:

Originally Posted by mowoc

Also, there is a ton of grease in that thing - do I clean it all out?

You need to remove 100% of the old grease from the hub and the bearings. Soaking the bearings in mineral spirits (paint thiner) works well; rinse in hot water or use brake cleaner to remove the solvent. Once they are clean, inspect the rollers and races for defects-grooves, spalling, galling etc.

Also, wash your new rotors (before installation) with hot soap and water to remove any rust preventing compound. (Brake cleaner won't work on some compounds.)

E150GT · #34 05-16-2009, 09:17 PM

I did this job on my car two years ago. It took me hours as the hub and rotor would not separate. DO Not do as I did and put the hub back wrong as I did. Mercedes should not have made the lug bolt holes and the hub/roto holes the same as they can be confused. I got it all back together and then the wheel would not line up to the holes for the lug bolts because i used the wrong ones and had to do it over. Another thing, Have you done the rears? I strongly suggest not using wagner brand. I usually use them on my fords, but they just dont have the fit they need. I would suggest using a good german brand.

tangofox007 · #35 05-16-2009, 09:24 PM

Quote:

Originally Posted by E150GT

Mercedes should not have made the lug bolt holes and the hub/roto holes the same as they can be confused.

Apparently, they can be confused even when thay are not the same!!!

E150GT · #36 05-16-2009, 09:30 PM

Quote:

Originally Posted by tangofox007

Apparently, they can be confused even when thay are not the same!!!

they have the same threads so they pretty much are.
****edit****
thinking back to that night th only thing I can remember is that the holes can be lined up wrong. I also live by a rule now. Unless I have to I work on my car on saturdays only and I now buy German only parts.

mowoc · #37 05-17-2009, 01:47 PM

Well, I finally got that $%$$ seal out. It was in there VERY tight.

I found the other bearings as well. Now, for (hopefully) the last few questions:

1. The races appear to be fine. I see no blemishes on the surface. The inside of the hub seems to have some light scoring though - is that normal?

2. How long do bearings normally last? I do not think the ones in my car are original (they say made in Japan).

3. When I re-pack the hub I start with the inner race bearings - right? I pack the bearings with a LOT of grease. Then do I put more grease in the hub between the races? Finally, I pack the outter bearings when the hub is back on the car, right?

tangofox007 · #38 05-17-2009, 02:03 PM

Quote:

Originally Posted by mowoc

The races appear to be fine. I see no blemishes on the surface. The inside of the hub seems to have some light scoring though - is that normal?

The hub itself will have machine marks. The thing that matters is the bearing race, not the hub bore.

Quote:

Originally Posted by mowoc

I pack the bearings with a LOT of grease. Then do I put more grease in the hub between the races?

Too much grease is not good. You want the roller portions filled with grease and some grease in the hub, but don't get carried away. MB specifes a partucular weight for the grease, but unless you have a scale, that won't be helpful. (For a W123, MB specifies 60 grams of grease per axle. 45 grams in the bearings/hub and 15 grams in the dust cover.)

It makes sense to install the inner bearing first, then the seal. Put a light coat of grease on the axle, including the shoulder where the seal rides.

Matt L · #39 05-17-2009, 02:29 PM

Don't fill it up. Ensure that the outer surface is completely covered in grease, and that there is some grease between, but not so much that it will be oozing into the bearings or you will be sorry later. Be very careful fitting the hub onto the axle shaft. The hub is heavy and it is quite hard to keep it perfectly lined up while you get the seal lip over the sealing surface on the knuckle.

tangofox007 · #40 05-17-2009, 02:33 PM

Quote:

Originally Posted by Matt L

Ensure that the outer surface is completely covered in grease...

???????????

Matt L · #41 05-17-2009, 03:02 PM

Hmm... very badly worded. The inner surface. I was thinking "outer" surface, when looking through the hole!

Abadjay · #42 05-17-2009, 07:33 PM

When it comes to rear brake pads, does it matter what pads you put on the back of the car? I'm thinking of putting better pads in the back that are designed for mild performance and light racing, but I'm told they last a long time. Should I also change the front along with the rear when putting these better pads?

toomany MBZ · #43 05-17-2009, 09:41 PM

No need to change out the fronts too, let 'em wear down.

mowoc · #44 05-18-2009, 02:47 PM

Dang nab it!

I have gotten the first wheel done, and the second is almost!

Freakin outer bearings will not go on. It seems like they are sticking to the outside of axel just over the threads. Can I use force to put them back on?

On the first wheel the bearings just slid on and off.