Found Front Disk Hub not tightly bolted to Disk Rotor--Severe Damage occured?85 300D - PeachParts Mercedes-Benz Forum

Carrameow · #1 03-11-2003, 11:40 PM

I went to change my front bearing tonite and I noticed that the front disk hub and the disk Rotor were not joined together tightly!
There was Play between the bearing Hub and Disk Rotor if you can believe it. I had replaced the disk rotor myself 4 months ago and evidently the bolts had come loose.
I got a 10 mm Hex head and tighened all of the nuts attaching the disk to the hub.
Several of the hex bolts were a half to one turn loose.
After thinking it over I stopped repairs at that point. i was scared to think that the hub and disk were loose and what could have happened if they had separated at high speed with high braking force.
I am wondering if the play in the hub and disk when they were loose were enough to have cause some abnormal shear stress in the hex bolts or the hub and the disk and whether the whole assembly is Trash.
I mean someday I will be driving across the Verrazono bridge at 80 mph with my family in this car.
Any professional advice? Am i over imaginiing things? Did I fix the problem simply by tightening the hub nuts?

http://mywebpages.comcast.net/snow7ice/BENZ.html

IFound Front Disk Hub not tightly bolted to Disk Rotor--Severe Damage occured?85 300D

neileg · #2 03-12-2003, 04:48 AM

I think you are right to worry about the state of the rotor and the bolts. The hub is made of heavier stuff, but it is always possible that the threads have been damaged.

I would have expected there to be locking compound on the bolts to stop them coming loose. You did use new bolts when you replaced the rotor, didn't you?

sbourg · #3 03-12-2003, 10:03 AM

Well, I don't know how your brakes are set up, but every set of disks I have ever worked on have the hub-centric brake disk securely clamped between the wheel and hub when the wheel lug nuts are secured. Any disk attaching bolts (IF any) were there primarily to keep the disk secure while the wheel is off, and sometimes to provide a bit of additional positioning accuracy, to keep the disk from shifting while mounting the wheel.

Steve

Carrameow · #4 03-12-2003, 10:55 AM

Thats a good point--I didnt think of that! You have the Lug Nuts really doing the work---

#5 03-13-2003, 06:00 AM

If you had any play at all you would have felt it at speed. Any vibration would be easily noticable. I seriously doubt any damage has occurred however I visual inspection should be enough to determine if play has caused any abnormal wear.

Matt.

Carrameow · #6 03-13-2003, 07:27 AM

I did hear noise but I mistook it for a bad bearing

neileg · #7 03-13-2003, 11:26 AM

Yes...

I don't think my posting was very bright, was it?

Sorry chaps.

Carrameow · #8 03-13-2003, 01:09 PM

I dissassembled the Hub last night. Those bolts we are discussing pass through the Disk first and seat themselves in the Hub. The heads of these bolts are on the inside Disk Side.

The lugnuts that hold your wheel on pass through the wheel and seat themselves in the Hub from the other (out)side. However these lugnuts dont thread themselves in the Disk.They only pass through unthreaded holes that allow them to protrude through.

If these nuts we were discussing were missing, the Tire would only be fastened to the Hub. It wouldnt be fastened to the Disk.

Anyway I will look at it VEry closely again tonight.