Rear Axle bearing question

[mdbrandy]

I'm in the end game of putting the rear back together. Trying to install the rear inner bearings now. Drivers side went in fine. Cocked the bearing once, but second try was easy. Passenger side is another matter. I have tried about 5 times so far. The bearing will go in about 1/8 inch, and then no more. After fighting it a while, I took it out (tapping from the inside removed it with no real problem) and found a ridge on the hub surface that the bearing is an interference fit with. I didn't think it was there originally, but I polished it out with a little fine sandpaper and a scotchbrite. Tried installing the bearing again. No dice. 1/8 inch and no more. And I take it out, and the ridge is back again. I feel the outer edge of the bearing, and it seems just slightly raised around the edge. I don't know if that is normal, or if it was caused by trying to install it in the hub, and having it dig into the hub to create that ridge.

Anyone else seen this kind of problem? Solutions? I don't have the precision measuring equipment needed to measure the ID of the hub versus the OD of the bearing. I thought about knocking off the "sharp" corner on the bearing with a little fine sandpaper, but that's a little scary. I guess I have to polish out the ridge in the hub again now, but that'll only work so many times...

Oh, and the ridge in the hub isn't uniform around the circumference, so it seems like cocking the bearing might have caused it, but it occurs at a couple places around the circumference, like the inner hub is out of round or something...

[mdbrandy]

So why do I seem to have a knack for asking questions that no one has a ready answer for? Or are the questions just that stupid :stupid:

[LanceM]

Put bearing in the freezer for an hour or so, when ready grab the bearing and run and install it in the car. Freezing it will reduce it's diameter a thous or so and allow it to install easier. Better yet if you could heat the housing some to help increase it's diameter.

[mdbrandy]

Put bearing in the freezer for an hour or so, when ready grab the bearing and run and install it in the car. Freezing it will reduce it's diameter a thous or so and allow it to install easier. Better yet if you could heat the housing some to help increase it's diameter.

Freezing the bearing had occured to me (late last night), but I'd rather not heat the housing if I can avoid it, since it is all newly clean and painted and all. Burning all the new glossy black paint off would be a tragedy ! Of course, not being able to drive the car because I can't get the bearing back in would even be worse...

I shall try the feezing bit with the bearing tonight and see if that does it. If not, then I can always repaint...

[ChrisA]

Hi Mark, hey where did you get the bearing? I once got some at Carquest and they were a little out of tolerance. You're on the right track with the sandpaper and scotchbrite. I suspected an out of round housing right off the bat. What are you using to seat the bearing? I went and paid good money for a bearing/race installer set. It really helps distribute the force evenly around the entire bearing.

Much luck to you,

Chris

[mdbrandy]

Hi Mark, hey where did you get the bearing? I once got some at Carquest and they were a little out of tolerance. You're on the right track with the sandpaper and scotchbrite. I suspected an out of round housing right off the bat. What are you using to seat the bearing? I went and paid good money for a bearing/race installer set. It really helps distribute the force evenly around the entire bearing.

Much luck to you,

Chris

OEM Nissan part. Bought from the good ol' local Nissan Dealer (I'm finding that some parts are just as cheap or cheaper through Nissan as through MSA or VB!). I went with Nissan on these since I DO NOT want to do it over again! So hopefully OD tolerance on the bearing isn't the problem. I figure the 27 year old hub is more likely the problem.

I have a nice bearing/seal installer set - aluminum cones that can reverse to seat bearings, seals (flat side) or races (cone side). Bought it back in the late '70's when I was working on my first 240Z and been carrying it around ever since! Great tool.

[ChrisA]

OEM Nissan part. Bought from the good ol' local Nissan Dealer (I'm finding that some parts are just as cheap or cheaper through Nissan as through MSA or VB!). I went with Nissan on these since I DO NOT want to do it over again! So hopefully OD tolerance on the bearing isn't the problem. I figure the 27 year old hub is more likely the problem.

I have a nice bearing/seal installer set - aluminum cones that can reverse to seat bearings, seals (flat side) or races (cone side). Bought it back in the late '70's when I was working on my first 240Z and been carrying it around ever since! Great tool.

Hi Mark, I'd have to agree with you on the bearings and the hub. Don't normally see problems with OEM parts. Do you have any valve grinding compound? The blue paste stuff? You could put some on the bearing and set it into the hub bore and the material transfer might tell you if the hub is out of round. Do you remember if the old bearing came out easy and left any scoring in the hub?

I'm at a loss as to helping you get that bearing in. I think the freezing is the best bet so far.

Chris

[First Gen Z]

If all else fails you could take it to a shop that has a press and have it pressed in. If your hub is out of round you may not get the bearing in by any other means.

[mdbrandy]

Hi Mark, I'd have to agree with you on the bearings and the hub. Don't normally see problems with OEM parts. Do you have any valve grinding compound? The blue paste stuff? You could put some on the bearing and set it into the hub bore and the material transfer might tell you if the hub is out of round. Do you remember if the old bearing came out easy and left any scoring in the hub?

I'm at a loss as to helping you get that bearing in. I think the freezing is the best bet so far.

Chris

Don't have any grinding compund specifically, but I'm sure I could come up with something. I'm going to try to freezing thing first. I'll repolish the hub internals, freeze the bearing and try to get it pounded in. If that doesn't work, I'll probably have to take the darned strut back off the car and do something different. Don't quite know what yet...but your "marker paste" thought might be a good diagnosis method if I can't get it in frozen.

[mdbrandy]

If all else fails you could take it to a shop that has a press and have it pressed in. If your hub is out of round you may not get the bearing in by any other means.

I actually have a 12-ton harbor freight press and have had pretty good luck using it. I pressed the outer bearing off the axle with it, and then, after constructing the appropriate "drift", I pressed the new outer bearings on with it.

I have found, however, that it is all to easy to destroy parts with the press instead of fixing them. I believe I have slightly bent the yoke of one of my half-shafts while pressing out the U-joints. Don't know what I'm doing about that yet. I'd be really hesitant to press this bearing in, knowing that it is gouging the hub walls. More likely to destroy things than really get it in.

[LanceM]

Mark,

For heat you could use one of those halagen (sp?) work lights if you have one, up close and focused on the hub would bring it's temp up quite a bit but still short of burning off the paint. I recommend putting the bearing in a plastic bag during the freezing part, this will let you transport it without body heat warming it and keep frost off of the part too. I have used this method many times working on antique tractors and it works great, I've had some that seemed that they were going to be a pound to destruction become a fall in place with the freezing or heating method depending upon where it is going, and for sure a cold bearing is much easier to handle than a hot one!!!

[ChrisA]

Hi Mark and Lance,

The freezing method is a tried and true method. I'm a little worried about condensation forming on the bearing after its removed from the freezer. If you get it driven into the hub, maybe shoot it with some water dispersement spray of some kind, WD40 or whatever. To remove any possible water contamination. Just a thought. As hot as it is here today, it would condense instantly!! I realize the amount of water would be small, but I seem to contaminate bearings at will!!

FWIW,

Chris