Collapsed wheel bearing.

[Denzeldude]

I've owned my Esprit long enough to know that owning an Esprit inevitably means that even if you didn't want to know how every mechanical part of your car works, you soon will.

After a catastrophic failure and subsequent repair of the spline on a rear driveshaft, the mechanic repacked the original wheel bearing when putting the driveshaft back in. First drive since and the rear wheel was loose and slightly wobbly, but still just drivable. I took it back to the guy who said the bearing had collapsed.

For the next step of my mechanical knowledge, can someone explain this to me. Does it mean the bearing cannot be fixed, and needs replacing with a new one?

Thanks, yours-in-learning,

Evan

[Vulcan Grey]

I've owned my Esprit long enough to know that owning an Esprit inevitably means that even if you didn't want to know how every mechanical part of your car works, you soon will.

After a catastrophic failure and subsequent repair of the spline on a rear driveshaft, the mechanic repacked the original wheel bearing when putting the driveshaft back in. First drive since and the rear wheel was loose and slightly wobbly, but still just drivable. I took it back to the guy who said the bearing had collapsed.

For the next step of my mechanical knowledge, can someone explain this to me. Does it mean the bearing cannot be fixed, and needs replacing with a new one?

Thanks, yours-in-learning,

Evan

Yes, new bearing is required.

I know the later cars use a sealed ball bearing for the rear, so I'll assume yours does too.

There is an inner race touching the axel shaft, surrounded by a cage with ball bearings, and on the outside is the outer race which is pressed into the hub.

The inner cage with the ball can break (probably what happened to you). This allows the inner and outer races to move around making it wobbly.

When pressing a bearing in or out you must remember to press only on the inner race (if possible) or you can break apart the bearing. When a sealed bearing fails, this is pretty much what happens, only over a long time and with alot of wear.

The rear hub carrier will nee to be carefully removed (they are cast aluminum and fragile, NO pounding of any sort) and then the bearing will need to be pressed out of the housing, you should really heat the whole assembly in the oven before removal and reinstallation of the bearing!! That will keep the bearing race from damaging the aluminum.

[Tony K]

The S1/S2 requires a little bit of additional care:

When removing the wheel bearing, the shaft goes out "the back" (toward the center of the car) of the hub carrier and the bearing comes out "the front" (the side of the hub that has the wheel).

The thing that requires the most extra special care is pressing the shaft out of the bearing. There is a remarkably thin ridge that runs the perimeter of the outer race on the back side of the hub carrier to locate the bearing. When you press the shaft out of the bearing, you have to be careful to not apply too much force, or you will break this little ridge. What tends to happen is the inner race siezes to the shaft, and when you try to press the shaft out, it takes the whole bearing with it and the outer race of the bearing breaks the little ridge. If this happens, there are ways to repair it, but a new (or secondhand) hub carrier is difficult and expensive to obtain. If the shaft presses out with relative ease, then all is well; if it is siezed, then you may be better off "blowing apart" the bearing so that the inner race comes off with the shaft, and then work on getting it off separately. Throughout this whole procedure, heat helps.

The outer race is usually not seized into the hub carrier. It usually comes out fairly easily. But if you do have to press it out, just make sure you are not pressing on the ridge at all.

Putting the new bearing in is almost fun. Clean the hub carrier and put it in your oven and set the temperature to 200F degrees (close to 100C). Leave it in for a good 20+ minutes so it is thoroughly heated. While it is heating, pack grease into the new bearing (they are not sealed bearings -- more in a minute) and smear a thin coating of anti-sieze on the outside of the bearing. When you take the hub carrier out of the oven, the new bearing should slip in very easily -- it will almost go in on its own!

Once the bearing is in place, stuff more grease around the sides and install the new seals. Yes, you will need new seals. The bearing itself is not a sealed bearing, but you will have to install a seal on either side of it on the hub carrier. They look like crankshaft or camshaft seals. Best to put them in while the hub carrier is still warm, as they will go in easier, too.

Inserting the shaft into the bearing is not too difficult. Again, I would use anti-sieze to avoid future disasters (and you know you will be doing this again).

When reinstalling everything onto the car, the tightening of the hub nut is critical. It has to be something like 200 or 220 ft-lbs (I forget, so look it up).

Edited March 22, 2007 by Tony K

[Esprit Aviation]

Any chance those rear bearings are the same as Audi front wheel drive bearings? There are a few various sizes in the different models.

Lee

[markt]

Just a point to add on Tony's nice description (as always...

To remove the bearing, Stick the hub in your deep-freeze over night... might sound silly I know, but I promise this works for stubborn parts... To replace, put the new bearing on ice overnight - the metal contracts, and pops right into the hub.

I have done this, and it does work

[bpaar]

The S1/S2 requires a little bit of additional care:

if it is siezed, then you may be better off "blowing apart" the bearing so that the inner race comes off with the shaft, and then work on getting it off separately. Throughout this whole procedure, heat helps.

Is there a procedure to blow apart the bearing easily? I really struggled with the first hub, knowing that I can't easily replace it I was really careful... took forever.

Thanks,

Bill