Rear Axle/Bearing Carrier Issues

[Rick Waters]

After about 15 years with dry rear brakes, my Left hand rear brake suddenly filled with axle oil. My car has tapered rear half-shafts and hubs from Phil Marino, in California, along with the bearing nut with the lip seal pressed in place.

Upon disassembly, I found that the bronze bushing in the axle housing tube slightly worn at the top. But more importantly, I found, upon removing the retaining nut and tab washer, I found that the outer seal on the sealed ball bearing loose and mangled. I was checking to see if there were any shims in the bearing carrier-to-hub interface, and did not find any, but was very surprised to find the mangled seal.

I bought a new bearing, new seals for the nut and the carrier-to-axle interface.

My questions are: Is it necessary to replace the bronze bushing? and any one have any idea on what could cause the seal on the bearing to come loose? I believe the whole assembly was done at a local MG shop when I bought the axles, so I'm trying to dodge the bullet about my Klutzy assembly skills ;-)

[Steve Simmons]

That's strange. Does it look like the rubber seal overheated? Can't think if anything that would physically tear it up like that.

[Rick Waters]

Not overheating at all. The actual bearing was fine. My guess is that either the shop that installed the whole mess used a drift to tighten the bearing nut, and the drift slipped and hit the bearing seal, or, perhaps the same thing happened to me, when I was folding the tabs up on the retaining washer? Can't recall anything, though.

Is there no washer or anything between the tab washer and the bearing?

[Steve Simmons]

Not that I'm aware of. Here's mine before the rebuild, can't find a photo from after (now with Bob's setup).

And no, the tabs weren't folder over!

[Gene Gillam]

Rick, the bronze bushing in the axle housing has a reverse scroll which aids in keeping the differential fluid from the brake area. If it's worn enough that the scroll area is wiped away it won't hurt to change it. Replacement is covered here: http://www.mg-tabc.org/library/TC_rearaxle_rebush.htm

I'm not familiar with the bearing nut with the lip seal pressed in place you mention. The bearing nut with a lip seal that I've used doesn't need the tabbed washer shown in Steve's photo...Bob Grunau sells them and they're so much easier to work with.

[Rick Waters]

The scroll is only partially visible on my bushing. I'll order another one. My understanding is that they are "handed".

Now to find the puller I used last time (borrowed).

Can't even remember whether I used anything special to install the bushing last time. Any tips here?

[Gene Gillam]

I've just carefully tapped them into place with a block of wood.

[Rick Waters]

Sounds good. Thanks

[stephen stierman]

I replaced those bushings in my car some time ago and did find some indications of contact as you mention and suspect to some degree this may be normal considering slight movement of the axle. I also suspect in reality they do little to keep lube out of the brakes. In your case, even with the tapered axles, is the hub still tight on the axle? I assume it would be, but if the nut was slightly loose, there could have been some movement allowing damage to the seal with the resultant oil entering the brakes. The entire set up working, whether it be original or upgraded, depends upon the axle being tight in the hub, and if this is not the case wet brakes are the result.

[Rick Waters]

Yes, the hub is tight on the tapered hub, no question about it. More background on this: about one year ago, after the 15 dry years, I noticed some symptoms of oil leaking into the brake. I removed the brake drum, and discovered that the bearing-retaining nut was not totally tight. I tightened it, and crossed my fingers, but the problem returned. Although I think I was careful with the tab washer, it's possible that I damaged the seal which is part of the bearing.

During the time period when the nut was loose, I think there was movement which damaged the seal in the nut, which is probably the best line of defense here. Ii have no idea how long this assembly was loose, or even why it came loose.

I have reservations about how useful those bronze bushings are as you mentioned. I suppose it won't hurt to fit another one while everything is apart. I'm fitting a new seal into the nut, new sealed bearing, and new seal on the bearing carrier to axle joint. I note that the axle shaft has some slight ridging where the seal rode, and I'm working on polishing that out with 600 grit. Can't figure out how anyone could fit a speedy sleeve so far onto a shaft?? Not sure it's even needed here.

Anyway, this, of course, is part of the reason I have a TC, keeping my mind active and my hands dirty, and not the other way around!!

[Eric Worpe]

The bronze bushings can serve another purpose if made longer, say 1.5 inches long. This would enable them to protrude internally in the back axle tubes forming a circular dam. Any oil running down the tubes due to say parking on a slight slope, would lap against the end of the tube but be unable to flow past the extended bushing.

[Rick Waters]

Understood, Eric, and a good point.

Right now, I'm still trying to find a suitable puller in order to remove the old bushing. The method on the T-ABC site only works if you remove the diff carrier, to allow the tool to be put in place. I did have a two prong, light duty puller last time I did this job. It worked by turning the fingers so that the "hooks" pointed outwards. I cannot find a similar puller this time around. (Borrowed one last time, but that shop has changed hands)

[Steve Simmons]

What about a big lag bolt? Just thread it right into the bronze, attach a puller and yank it out. The worst that could happen would be tearing up the bushing but not getting it out.

[stephen stierman]

Take a good sharp hack saw blade and cut a couple or three slots in the bushing and collapse it in on itself, it will come out.

[Jim Ellis]

Take a look in the Technical Articles section under Resources. There is an article "Oil thrower bushing removal" that details how to build a puller. I spent days trying all kinds of things before I came across this article. A trip to the local hardware store and 5 minutes later and out they came!

[Steve Simmons]

Jim, I assume your diff unit was removed already? I don't think that tool would work if it was still in place, unless I'm missing something. Wouldn't be the first time I suppose.

[Jim Ellis]

No, I did both sides with the rear end still on the car, just as in the final picture in the article. I didn't think it would work, but I didn't want to take the rear end out of the car, so I tried it and was amazed at how easy they came out.

[Steve Simmons]

How did you get the tube and related items behind the bushing to pull it out?

[Jim Ellis]

The key is the ground down hardened washer, when it lays loose it fits through the slinger, then as you tighten the bolt, it stands up straight and no longer fits through the slinger and out the slinger comes.

[Steve Simmons]

Brilliant! Thanks for the clarification.