W123 rear wheel bearing removal help needed
 

Dear All,

I thought I'd call this thread "How rough should I get" but I've already started one by that name for my propshaft removal... I'm kind of in a similar position though with the rear wheel bearings.

I'm following the instructions on the Peach Parts wiki :-

http://www.peachparts.com/Wikka/W123RearWheelBearings

I'm stuck at the beginning. I've de-staked the locking on the slot nut and I've bought (at great expense from the dealer) the MB special tool (115 589 02 07 00).

The special tool fits like a dream - so no problems there. Only I don't know how much torque it is designed to take.

Does anyone know this?

I reckon (based on my weight and the length of my 3/4" bar) that I'm applying about 400Nm / 295 lbs ft but the slot nut is just stuck fast. In fact it is laughing at me...

So what should I do:-

1) Buy a longer 3/4" bar and try again?
2) Think of another solution like drilling the bloody thing out?

I've now killed 4 bolts on the wheel side of the hub trying to stop the hub from rotating. I don't want to kill my special tool - I still need it to fit the new bits!

Any advice will be greatly appreciated.

What about adding some heat to soften the locktite?

Locktite?
 

Did they / do they use locktite as well as peening the slot nut?

Hi, I've done it and the torque is not that great, surely not enough to shear a bolt. Are you sure you've got the nut fully unstaked? You are right to be concerned, because the fingers on the tool are not that thick.

I'm pretty sure everything is unstaked - I've run a thin screw driver around the edges and bent it all out as best I can. I'll post a photo tomorrow.

Does anyone know how a Mercedes dealership would do this job?
Do they have another special tool that attaches to the splines thus helping you to lock the hub in place?

To answer your question the Mercedes has a tool that bolts to the Hub. Not shown in the thumb nail there is also an Arm that Bolts on to the end of the tool.
For removal the use of heat was a good idea.
Also take good look and see if someone has used a Center Punch and staked over some of the Threads on the Hub.

X2 Diesel & rrgrassi !! I once nearly gave up trying to loosen one of those nuts. Make sure you have the hand brake on real tight, it helps. Heat was the only way that worked for me.

To hold the Hub I am thinking what would happen if you put the Brake Rotor and the wheel back on and lowered the Wheel down on a block high enough so that there was room to get under the Car. Apply the Parking Brake as layback40 said.
I believe all that would keep the Hub from rotating while you try to turn the Retainer Ring.
Also Penetrating Oil before and inbetween heating can be helpful. However, becareful as it can be a Fire hazard.

I suppose an old Brake Rotor could be turned into a Hub Holding tool if a Handle was attached to it.

I did mine about a month ago and I didn't even need a cheater bar. If you are replacing everything I would use heat.

Mike

OK thanks folks - fire it is!

If you have an oxy-acetylene set, a pencil flame is best. You shouldnt need much heat.

Well I've been patient for about a week now - heating the thing up and applying penetrating oil and it is still stuck like a stuck thing...

I've been using a plumbing soldering (butane) torch as I have nothing else. Do I need to get a propane torch? With this Butane torch I can get the nut to smoke and the penetrating oil to fizzle but I can't get it red hot.

How hot must it get?

I am not sure what the plumbing soldering butane torch looks like. However, it looks as if at some point you will have no choice but to use brut force to get it off.
Were you able to find a way to keep the Hub from rotating?

The only other possible way I can think to loosen it is to pick a spot on the Retainer Ring between 2 of the slots that the Special Pin Wrench goes in and drill all the way through the Ring. Then get simething like a small Chisel into that hole and spred the Ring out.
After that put on the Pin Wrench and see if you can turn it off.

Make believe the below pic is the Retainer Ring.

Center Punch and then drill through the ring at a spot between 2 of the Pin Wrench Grooves; like where the Red X is.

If that does not split the ring completely get something in the hole like a Punch or Chisel and split it. That should allow the ring to spread a little and you should still be able to use the Special Pin Wrench to unscrew the Ring.

If you bugger the threads on the hub a little; ounce the Hub is off you can use a small Triangular File and clean the Threads up.

If you Drill all the way through the Ring you will need a new Ring and maybe the Circular stamped Metal Locking ring. You Should not be able to drill into the actual Bearing as it is extremely hard.

Well here is an update - the nut is off!

That's the good news.

Before I give the bad news I think I need to own up to some important information - I'm doing this off of the car. The trailing arms have long been removed from the sub frame and I'm busy doing other things such as replacing brake and fuel lines and rebuilding the front suspension, treating rust, and cleaning out fuel tanks etc etc etc

Doing this job off the car is turning out not to be ideal. But I have the time at the moment to be stubborn.

I'm now trying to press the hub out of the trailing arm.

The DIY on the Peach Parts wiki says to hammer it out with a brass punch and then use a disc (brake) as a sliding hammer.

My question now is how much force should I use here?

Has anyone had to resort to heat here as well?