ITA 240SX Wheel Bearing Re-packing

I changed right front and left rear wheels bearings a few weeks ago and was able to re-pack them with some high-temp race grease. Here's a little write-up on what I did. I took the bearings apart, cleaned out all the grease, and then re-greased them with some Neo Synthetic.

Front bearing: The front bearing does come apart, but you have to bang on the inner piece pretty good to get it to come out. There's little tabs in the ball cage that lock the inner piece in place and you have to bang it out of those tabs. I did not remove the grease seal on the one side, but you could probably do it if you wanted. I didn't feel like dealing with the hassle of getting it back in. I was able to clean the bearings on that side while they were still in the housing. You just have to move the bearings around a little bit. The front bearings have the balls locked into the cages so don't try to remove the balls. Just remove the entire assembly. Re-assembly is pretty easy, just put the ball cage back in and tap the inner pieces back in.

Rear bearing: The rear comes apart easier than the front. A little tap will get the inner piece to come out. The balls in the rear do pop out so I took them out to clean them. I was able to clean everything without removing the grease seals, but when I went to put the inner piece back in it wouldn't seat correctly. The inner piece seats into the grease seal and I couldn't get it to seat all the way with the grease seal in the housing. I wound up taking the grease seal out, putting the inner piece into the grease seal, and then tapping the inner piece and grease seal as a unit back into the bearing housing. That was the only way I could get the inner piece to seat all the way and not leave a gap where dirt could get into the bearing.

Here's some pics:

Magic goo
http://home.comcast.net/%7Edmontgome...grease_web.jpg

Front bearing disassembled.
http://home.comcast.net/%7Edmontgome..._apart_web.jpg

Front bearing balls and cage.
http://home.comcast.net/%7Edmontgome...g_cage_web.jpg

Front bearing inner piece. Note the grove where the tabs in the ball cage hold the inner piece.
http://home.comcast.net/%7Edmontgome..._inner_web.jpg

Apparently I can only have 4 images in a post so I'll put the other pics in a separate post.

Front bearing back together.
http://home.comcast.net/%7Edmontgome...embled_web.jpg

Rear bearing disassembled.
http://home.comcast.net/%7Edmontgome..._apart_web.jpg

Rear bearing inner piece and balls.
http://home.comcast.net/%7Edmontgome..._balls_web.jpg

Just FYI, there's also a pretty good writeup on Motoiq.com for this.. Maybe that'll help others too.

Well after all my prep on wheel bearings I still had issues at the track (at the ARRC). I went out to bed new brakes on the test day and had big vibrations. Came back in and proceeded to check all four corners. Both front wheels had play in them. The right front had the new wheel bearing I just put in and the left front bearing was replaced a year ago.

Turned out the left front bearing was actually sliding in the hub. I could actually pull the wheel out and push it back in. The only thing keeping it from sliding all the way off was the retainer clip. :blink: Took it over to Bowie and Matt Repert to look at and the only thing we could figure is that the hub itself was bad. Luckily this was a home race and I had some spare hubs at home from the new tub and had bought some extra wheel bearings. I had a new wheel bearing pressed into one of the spare hubs and everything was nice and tight after that. I wasn't sure if I had fubar'ed the bearing I took apart that was on the right front so I didn't take the new one for the left apart (more on that in a sec). Only thing I can think of is that over time when the wheel bearings start to get loose they then start to wallow out the hub somehow. Either that or the negative camber somehow puts odd side loads on the hub and bearing. The hub being loose has probably contributed to my bearing issues.

The right front also had play like I said. The bearing did not slide in the hub like the right front, but there was still play when you did the top/bottom shake as well as left/right. This was the new bearing that I had repacked. I was concerned I had somehow screwed up the bearing when I took it apart so I had a new bearing pressed in that I didn't take apart. There was still play when I shook the wheel. I actually moved the hub to the other side of the car and the play followed the hub. All I can figure at this point is that the hub is starting to go bad like the left front and that is allowing the bearing to move slightly in the hub. It wasn't so bad that I thought it was an issue for the race and did the race with no problems. Over the off season I'll put on one of the spare hubs and make sure the play goes away. I'll try using the bearing I repacked and see how it goes.

So at this point I'm not 100% certain that the front bearing I repacked is ok. I think it is, but the possibility exists that I messed it up somehow. I won't know until I start playing around with replacing the hub. The rear bearing I did seems to be fine.

What did I learn?
- Split apart the bearings and repack them at your own risk. I think it's ok for these bearings, but the possibility exists that you might damage them somehow. Matt Repert said that they use sealed bearings on the BMWs and you can't split them apart or you'll damage them. It sounded like they were put together differently than these bearings, however.
- Hubs can go bad. Even after you put in new bearings check for play.
- Don't assume your bearings, hubs, and suspension have no play even if you just replaced them. Get the car up in the air at home and shake the crap out of each corner. I should have found the play in the front wheels before I went to the track, but I assumed everything was ok since I had just replaced one bearing and the other was just a year old (with only 3 weekends of use on it). Spending your test day with both front wheel assemblies off the car trying to diagnose problems sucks.

David

The hub going bad is very common on nissans.
when the first bearing fails, it starts spinning against the hub and tears it up. quite often they fit tight enough that you don't think there's an issue as you can't move them by hand- but they're usually already bad. you start putting thousands of pounds of force on them and those tiny clearances suddenly start getting real big and causing the new bearing to spin on the old hub.

Ran into that myself a while back... Best thing is to take a VERY close look at the hub when you kill a bearing- if the surfaces don't look brand new with machining marks on them, then throw them away and replace the hub and the bearing.

I've even gone to the point of picking up junkyard spindles w/ bearing and hub, then tearing them apart and using the hubs with new bearings. you get a "new" hub for about $50 that way- way cheaper than a new one from Nissan.

If I had those "cartidge bearings" I would not be ripping them apart to repack.

Many people do it, but I still just think if you buy a quality bearing, why mess with it.

Hubs are a whole other issue, but all hub failures I have experienced were Hub nut torque issues. If they get loose, both the hub and bearings suffer.

The torque is also an issue with these cars. For the S13, you need to torque them to the MAX of the factory settings, if not a little higher. The factory spec on an S13 chassis is like 180-220ft lb or something. Nearly the identical bearing and hub on an S14 chassis is specd at like 220-250ft lb. those are ballpark from memory, but the point is the S14 uses the same damn bearing and it's torque spec is 40ft lb higher. The guys that torque the crapola out of the hub nut tend to have better longevity than the guys that run it at minimum of spec..


The reason for rebuilding is the grease used in the bearings from the factory is junk for the heat seen in road racing, and there is a fairly short life of bearings under race use. If you take them apart and repack them with better grease, they last quite a bit longer.

That said, some of these bearings you can take apart and repack. others you can't. On most of the "Nissan" bearings I've seen, the shell just slides apart by hand. Others are pressed together and I think you wind up doing more damage in the rebuild process by deforming the races than if you were to just leave them there and run the junk grease.

There is a way to repack the bearings without taking them apart. You just need a needle for your grease gun.

... And a powered parts washer to flush out all the old grease.

Quote:

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Originally Posted by Tristan Smith

There is a way to repack the bearings without taking them apart. You just need a needle for your grease gun.

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They also make tools just for packing bearings - like this one. Of course, those only work if you can remove the bearing from the hub.

Then again, I was taught loooong ago how to pack bearings by hand - just put a big gob of grease in your palm and work it into the bearing until it squishes out the other side. Cheap and effective :D

On edit: I was also going to say that I'm always surprised to hear about these hubs/bearings going bad. I bought new bearings several years ago, planning to replace the ones on my car (the ones that were on the car when I bought it in '02), and they're still in the boxes. And I check them before every weekend. Seems like maybe under-tightening could be leading to the problems? Or I am just incredibly lucky?

The problem with simply repacking bearings like that is that you need to remove the old grease. Often they're different soaps (moly based instead of lithium base, etc etc etc) and the greases don't mix, or will chemically fight with each other and cause other ugly issues. So it's important to remove the old grease before packing new stuff in.

Torque spec for the S13 front bearing from the FSM is 150-175 ft-lbs. I've been using 180. I *think* it's ok to split apart the front bearings, but am not 100% certain at this point. The inner pieces are just held in place by the tabs on the inside of the plastic bearing cages and I don't see how popping out the inner piece could hurt things. I won't know more until I put a re-packed bearing into a different hub.

I think using hubs off used cars is fine and I plan on getting a couple more to keep as spares.

I'm definitely surprised you haven't seen issues Earl. I'd check the wheels periodically and if you get any play replace the bearings immediately.

David