rear hub oil seal

Post by **winger300** » Mon May 31, 2004 4:42 pm

Just noticed my rear hubs are leaking oil out...

Removed the halfshaft and hub, the oil seal is shot.

So whats the procedure for removing the bearings? they are in good condition, but is there any way to remove them without destroying them? Or should i just replace them?

Both ways, whats the best procedure?

Thanks.

Post by **Willie** » Mon May 31, 2004 9:35 pm

Are you sure that it is only the oil seals(you say that BOTH of them
are leaking) this may indicate too much pressure in the axle.
You should check that the plastic breather on the top of the diff
case is not blocked up. There is a special tool for removing the
bearing but I have never seen one so,unless someone has a
better method you will have to tap it out and check it carefully
when it is out. I have always fitted a new bearing as a matter
of course. Check that the surface of the axle casting
on which the oil seal revolves is not pitted or corroded. Should
you fit new seals and still have a leak then the thing to do is to
NOT fit the seal right in to its housing i.e. leave it say 1/8" away
from its original position so that the seal is now running on a new
section of the casting. Use the correct paper gasket on the half
shaft flange because it gives the correct bearing preload.

Post by **winger300** » Mon May 31, 2004 10:03 pm

i'll check the breather hole. On inspection the oil seal was very brittle and hard, and also it now stuck to the inside of the hub. I spent about 3 hours chipping away it, and its not all off, looks like someone using some silicone sealant on it in addition to the oil seal ring! is this advised?

Post by **simmitc** » Mon May 31, 2004 10:11 pm

Don't forget the large rubber O-ring between the two parts of the flange. I've found that this is often the cause of oil leaks in this area, either because it's gone flat instead of round, or beacuse someone has left it out all toegther ! It's essential to have this in place as well as the paper gasket.

Post by **Willie** » Mon May 31, 2004 10:28 pm

NO! There should be no need for any sort of additional sealing
substance on the new rubber seal. Depends on the year of your
car as to wether you have the rubber sealing ring mentioned above.
It fits under the paper gasket and early cars did not have them.
The fact that you have added 'sealant' suggests that someone has
had trouble before. If you get more leaking then remove the hub
again and move the seal outwards by at least a 1/16"

Post by **Scott** » Tue Jun 01, 2004 1:50 am

Use the correct paper gasket on the half
shaft flange because it gives the correct bearing preload.

There isn't a bearing preload on the rear axle. It's just one roller bearing that carries the weight. The axle keeps the hub lined up correctly - which is why the hub can appear slightly loose when the axle is removed.

It's essential to have this in place as well as the paper gasket.

The later cars with the rubber 'O'ring should not be fitted with a gasket. 'O'rings are designed to have metal to metal contact. I suppose the gasket won't hurt, but it isn't neccessary to fit it.

Post by **57traveller** » Tue Jun 01, 2004 9:43 am

It's essential to have this in place as well as the paper gasket.

The later cars with the rubber 'O'ring should not be fitted with a gasket. 'O'rings are designed to have metal to metal contact. I suppose the gasket won't hurt, but it isn't neccessary to fit it.[/quote]

The "o" ring does locate for metal to metal contact, the gasket fits outside on the half shaft flange and is required.

Post by **Willie** » Tue Jun 01, 2004 6:57 pm

You are wrong there SCOTT.. of course there should be a paper gasket on the half shaft flange. Bearing preload? maybe the wrong
term, the bearing outer should project a few thou" from the hub
and the correct gasket ensures that the outer is securely pinched
between the hub flange and the half shaft flange to prevent the
bearing spinning in its housing.

Post by **Scott** » Wed Jun 02, 2004 5:42 am

I've never used the gasket together with the Oring - either one or the other depending on the year of the car. If the gasket sits outside of the Oring then it won't affect the Oring at all, but if everything is in good condition, the Oring will seal the axle.

the bearing outer should project a few thou" from the hub
and the correct gasket ensures that the outer is securely pinched
between the hub flange and the half shaft flange to prevent the
bearing spinning in its housing.

I hadn't noticed that before, but I've a dead car in my carport at the moment so I'll have a look tonight. The outer races on hub bearings don't usually get secured by a clamping force which is why they need to be pressed in. I could be wrong though - it has been known

(lol, no comments needed please)

Post by **57traveller** » Wed Jun 02, 2004 8:54 am

Willie is 100% correct. The reasons he advises are also in the BMC workshop manual.
I can think of many instances where the bearing's outer race is clamped by a cover and the joint/shim thickness is critacal for theamount of clamping required.

Post by **Willie** » Wed Jun 02, 2004 6:46 pm

SCOTT.. the workshop manual mentions the 'new' sealing ring
on the hub flange and describes it as, quote "an ADDITIONAL
sealing ring" on later cars. I take that to mean you use the original
sealing gasket PLUS the rubber ring on later cars?? I personally have
always done that. We will have to agree to disagree on this point.

Post by **Scott** » Thu Jun 03, 2004 1:05 am

Willie wrote:SCOTT.. the workshop manual mentions the 'new' sealing ring
on the hub flange and describes it as, quote "an ADDITIONAL
sealing ring" on later cars. I take that to mean you use the original
sealing gasket PLUS the rubber ring on later cars?? I personally have
always done that. We will have to agree to disagree on this point.

Apologies to Willie & 57.
I found that last night in the manual too. I also checked the parts listing & the gasket doesn't discontinue when the rubber Oring was introduced.
Looked at the hub on a car, the bearing protrudes approx. 0.010" from the hub which I guess is roughly the thickness of the gasket. I haven't experienced any problems without the gasket in place but I could see a potential for bearing movement (in/out) if too thick a gasket was used.

Post by **winger300** » Thu Jun 03, 2004 1:09 pm

when removing the other side i found that the two hubs i have are different. The lefthand side one has a grove that the rubber o-ring sits in, whereas the other side doesn't. I put the rubber o-ring in both sides anyway, i cant see it will cause any problem if its tightly sandwidched between the half-shaft flange and hub. They seem to be holding the oil back now with the new seals.

Better keep an eye on them for now though!