Multiple 9inch Seals Leakage

[Toyaddict71]

Hello all, back for more advice. Short version is I've replaced my passenger side 9 inch axle seal twice inside the week. First time I did a quick look, swapped seal, and put it back together. Second time, I did a much slower inspection and was very deliberate in order to prevent repeating whatever went wrong, but same result within 5 miles of driving. I feel confident I'm not compromising the seal during the process.
I looked at bearing and shaft. I didn't see anything that alarmed me. The bearing spun by hand. I didn't see any obvious scoring on bearing surface or the axle tube. But I feel like this has to be the issue and I'm just missing the problem. The axle might be original. the splines and contact surfaces feel fine, but along the shaft in between has some slight pitting.
I also checked the housing vent tube to make sure it was breathing as it should. Was honestly hoping it was clogged and possibly pressurizing the housing , but no such luck.
So I'm looking for any and all advice. Possible causes and/or inspection recommendations? I don't like just throwing parts at it, but thinking to just replace the bearing. Possibly even doing new axle and bearing along with another seal of course.
Thanks!

 

[.94 OR]

Stock style housing and shaft?

Bearing should be sealed out outboard of the seal?
Seal mating surface on the shaft should be inboard of the bearing retainer ring?
Axle shaft smooth in that area?
Seal getting damaged when axle is slid in?

 

[Toyaddict71]

Stock style housing and shaft? Yes
Bearing should be sealed out outboard of the seal? Correct
Seal mating surface on the shaft should be inboard of the bearing retainer ring? Correct
Axle shaft smooth in that area? Yes, it doesn't have any imperfections in that area.
Seal getting damaged when axle is slid in? I was very careful with it. Especially the second time. I won't say impossible, but I've done my best to eliminate installation error possibility.

 

[DirtDonk]

Is it still assembled? Can you tell whether the oil is leaking out around the outside of the seal, or between the seal and the axle shaft?
In my personal experience, my first axle shaft seal leaked also. It was around the outside perimeter of the seal and the axle housing. Sealant is applied during the manufacturing of the seal, on the side of the seal to help keep this from happening. Apparently even minor scrapes and scratches to the housing, from the seal removal process, can cause a leak.
In my case, I removed the axle, cleaned the area very well and put a bead of silicone sealer around the outside edge, where the seal meets the housing.
Never leaked again.

The only scratches to the housing on mine were extremely minor. But it was enough. Rather than remove the seal and ruin a new one, I tried the sealer process instead. Worked like a charm.

 

[DirtDonk]

When you do have the axle out again though, look at it very closely, and even if there’s a wear spot from the seal that doesn’t look or feel like a groove, I would still smooth it down with some cloth or Scotch Brite pad anyway.
And if you put a new seal in, maybe you should seat it to a different level. So not quite all the way up against the stop.
This puts the inner lip on a different spot on the axle shaft.
But that’s only if it’s leaking around the seal and the shaft. If it’s leaking around the seal in the tube, try the silicone trick.
And let it cure at least half a day, if not a full 24 hours, before you refill with oil.

 

[Toyaddict71]

Great ideas as always Donk. It's all buttoned up currently, but will pull wheel/drum to try to identify where it is leaking. If it's not obvious, any trick to identifying leak? As in should I elevate the opposite wheel slightly or anything else? If I silicon it, any silicon in particular? Thanks.

 

[DirtDonk]

No particular recommendation. Anything you normally use should work.
When I did mine, it was back in the late 70s or early 80s when there were not as many choices.
I think I used the standard black or blue RTV.

And yes, to verify where the leak is, clean the perimeter area with some carburetor or brake cleaner, let it dry, then tilt the axle to see where it’s coming from. Not by much though, since you don’t want oil coming out of the center bore.
However, you should be able to tell fairly easily with a quick visual inspection. If you have oil puddling in the end of the housing, but the rest of the seal in the axle shaft are dry, chances are pretty good it’s coming from the outside perimeter.

Clean and dry is critical for a good silicone application.
Clean it, dry it, apply it, and finger rub it in to make sure it’s down in the cracks.

 

[Toyaddict71]

Awesome. Going to tear it apart this afternoon. I will post results after. Thanks all.

 

[Toyaddict71]

OK, gave up on rest of my day and just opened it back up again. it's not leaking around the outer seal. I've had oil level just short of the center hole level for almost an hour and bone dry. I was so hoping a little silicon was going to fix this.

The bearing has a very slight residue of grease just pushing out just off the shaft. It is very slight but does have a little grit to it.

The shaft surfaces seem ok, not perfect of course but nothing I think would cause the high level of my leak and how fast it appears with new seal. I will clean up the surface as much as I can before trying to put it back together. I need to figure out how to upload photos. Maybe I'm just not a good judge.

 

[Toyaddict71]

After looking at some photos online from other axle shafts, mine may be worse than I thought.

 

[DirtDonk]

Nope, it’s the rules of this particular website.
You can only post pictures directly from your computer to the discussion if you become a contributor for $12 a year.
Other methods are to use an online image hosting site, such as super motors, or upload them to your “garage“ and ” gallery” functions up above.
That would probably be the quickest, but becoming a contributor is the easiest. With the garage we just have to go through multiple clicks to find them.

 

[DirtDonk]

Well, the good news about that is, maybe you won’t have to tear out your new seals. Just dress up the shaft itself. Crossing fingers!

 

[Toyaddict71]

Finally!!!!!

 

[Toyaddict71]

Man!!! Took better part of an hour to figure out how to get photos to upload. Had to resort to my phone

 

[Toyaddict71]

After cleaning them up. There’s a difference. Not sure if it shows in photos.

 

[DirtDonk]

It shows up very well. First, that seal is really trashed! Replace it
Second, but axle shaft indeed has a huge groove worn in it. Didn’t look like it when it was dirty, but now that it’s cleaned up, you can clearly see the groove.
That’s probably too big to be dressed down, but it looks like the perfect candidate too put the seal in at a different depth so that it doesn’t ride on the same place on the axle.
Maybe others have better ideas.

 

[DirtDonk]

How fast did you drive at this last time?
Looks like the seal was overheated. That would indicate riding on the dry axle area where the surface was rough or not conducive. But usually it takes higher speed to do that.
Maybe you got out on the highway for just a few minutes?

I bet a lot of that dark coloration on the axle that you cleaned off, was burned on rubber from the seal.
Do you oil the axle shaft, or the surface of the seal itself, before installing the axle?
If not, I certainly would the next time.

Unless I’m seeing it incorrectly? Is that inner seal surface wobbly and wavy?

 

[Toyaddict71]

Thanks for looking man. I was about to just button it back up. So 70 was the highest it ever got to. I prelubed everything with a layer of grease prior to installation to avoid dry startup.

Is the axle groove your referencing the machined like groove right in the middle of the smoothed area? Can't think of better way to describe it. Because I looked at brand new shafts and thought I saw the same one. So I disregarded it.

The seal surface is indeed wobbly/wavy, but came that way.

Thanks alot for taking the time to look this over for me. I knew I just don't have the experience to judge it on my own.

 

[Toyaddict71]

Looked with some magnification, there is a score line that runs JUST outboard of the machined mark. I missed it, eyes suck these days. its not deep, but definitely there. The seal has a kind of triangle design in the rubber material. makes that wavy look. I'll see if I can get a picture that turns out now that I have "mastered" photo uploads.

 

[Toyaddict71]

Triangles in manufacturing for seal