Front wheel hub doesn't want to be reinstalled, 123.153 - PeachParts Mercedes-Benz Forum

toomany MBZ · #1 06-20-2011, 08:22 PM

While in the process of replacing the front rotors, I had to use a puller to remove the hub assembly.

Once the new rotor was attached to the hub, new inner bearing and seal in place, just because, (nothing wrong with the old one) I can't get the assembly back on. It just doesn't fit. The old bearing doesn't want to fit on the spindle either.

I even mounted a cold pack on the spindle and heated the hub assembly in the oven to try and let physics help, but it still won't go on, even with a little persuasion from a slide hammer.

Any ideas?

leathermang · #2 06-20-2011, 08:55 PM

Do not do anymore of those ' bigger hammer ' deals.... you are going to damage something.... it should go on in the regular manner.....go back and look at everything again...

kolnerspieler · #3 06-20-2011, 08:58 PM

i remember having to hammer it in. I used a block of wood and placed it on the hub and held it in place and had my dad use a sledge hammer to hammer it on. It went on on the second hit all the way.

leathermang · #4 06-20-2011, 09:02 PM

I do not think that is normal or desirable .....You will not find ' sledge hammer ' listed in the FSM under tools for this procedure...

engatwork · #5 06-20-2011, 09:05 PM

Something does not sound right. Did you compare the size/dimensions of the old parts versus the new?

toomany MBZ · #6 06-20-2011, 09:43 PM

I agree there shouldn't be any tool necessary to remove or remount the hub, but it simply will not go on, it needed help coming off. No visible galling on the spindle.

The part numbers are what MB says they should be, as mentioned, not even the original bearing will remount.

The FSM doesn't have any special tool for this, it should slide on by merely pushing it in place, yet it doesn't.

tangofox007 · #7 06-20-2011, 09:58 PM

You might try cleaning up the axle stub with some emery cloth or fine paper.

Chas H · #8 06-20-2011, 10:04 PM

Quote:

Originally Posted by tangofox007

You might try cleaning up the axle stub with some emery cloth or fine paper.

This is the cure. Or a new spindle.
There are no wheel bearing slightly smaller than the standard bearing.
It's very important the wheel bearing slide easiy onto the spindle.

aeromechanix · #9 06-20-2011, 10:07 PM

I am currently in the process of replacing my front hub bearings. The inner race ID is only about 0.001" larger than the axle and forms a close tolerance fit. The hub/rotor assembly must be aligned carefully and squarely with the axle during installation. It will slide on smoothly when properly lined up and will not require any force.

Check for small burrs on the axle with a piece of cotton cloth. If necessary, lightly burnish the axle with a 3M pad. Even a very slight burr can cause the bearing to wedge and jam.

Diesel911 · #10 06-20-2011, 11:21 PM

Quote:

Originally Posted by toomany MBZ

I agree there shouldn't be any tool necessary to remove or remount the hub, but it simply will not go on, it needed help coming off. No visible galling on the spindle.

The part numbers are what MB says they should be, as mentioned, not even the original bearing will remount.

The FSM doesn't have any special tool for this, it should slide on by merely pushing it in place, yet it doesn't.

Is that area rusty?

Far fetched but; bent?

Stretch · #11 06-21-2011, 02:44 AM

Do you need some measurements?

I've got my car in bits as usual - I think the spindles are the same for cars with and without ABS - it is just the wheel bearing seal that is different right?

(Er you have got the right wheel bearing seal on there haven't you?)

A 005 997 44 47 is the seal for the front WITH ABS (I know 'cos I got these from the dealer and they didn't fit my non ABS hubs - I actually got a refund and was told to keep the seals - so here they are sitting on my cluttered desk!)

Stretch · #12 06-21-2011, 03:13 AM

If I remember correctly my problem with the ABS / non ABS bearing seal was the diameter of the seal sitting in the hub... so I don't think you're having a wrong seal problem.

vstech · #13 06-21-2011, 10:00 AM

A HAMMER???
no.
have all parts in your hands, and try each one by hand on the spindle to see where the issue arises... you will find the problem.

Stretch · #14 06-21-2011, 10:24 AM

I must say you are all being very good saying no to hammers! And nobody has even suggested fire and burning it off of the planet yet...

...at this rate we'll be able to club together and write a good quality best engineering practices report for the SAE.

leathermang · #15 06-21-2011, 10:27 AM

" Club together "... good one..