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I called and talked to John in sales.. and they are sending a RMA to return both bearings.
I'll continue working with FAG engineering to see if I can get to the bottom of this and help Pelican obtain more info. on the situation. It seems a bit bizarre to be sure. I would have a hard time believing FAG could make this level of manufacturing error, but since that's my job (sometimes helping manufacturers track down issues) I'm not surprised by just about anything. There are so many interesting things that happen, that you could never guess.

Old 05-13-2008, 12:27 PM
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Well, maybe it's a good thing I had to pull out and ruin my newly pressed in FAG bearing before using it. I was having some problems inserting the HUB in the new bearing, turns out I had the race of the old bearing still on the hub (how do I know what a stock hub looks like!

I popped it out and ruined my new FAG bearing and inserted an older stock bearing a friend had (BCA Bearing from Federal Mogul). This one has the seal locked to the outer ring. Sounds like it's for the best.
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Old 05-13-2008, 04:00 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #102 (permalink)
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IMVHO - I would wait just a bit before using any more FAG bearings on the rear axle or inspect very carefully that the seal slips easy on the inner ring and is attached firmly on the outer ring. I'm starting to be just a bit suspect on the FAG bearing number 527243CA.
The FAG people did not get back to me today... I emailed and called left message.

For that matter inspect any bearing you get FAG or othewise.

Oh... a stock hub looks like what you have with the inner race off.
Old 05-13-2008, 04:13 PM
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now that we are all getting sick of hearing about this..

Here is the puller I made.

you need an inner race from an old bearing to pull out a bearing... you will have this after pounding out the hub, the round black thing is a used cv taped on to a 3" abs coupler. I use the abs part because it pushing against the arm... and it no scratchy the arm. When you tape up the cv and it sucks through straight.. it will lock...and not move. This taped part is also excellent to pound on the cv tin without bending it/them. The items with the hose clamp is a outer ring from an old bearing... you need this to hold a frozen bearing and slip it in the hot arm. Then you put the large black assembly in the back of the arm and press on the edge of this bearing outside ring.. then you are only putting pressure on the outside of the bearing while pulling it in. The 1 1/4 to 1" galv reducer was used to pull out the first bearing but this is not the way to do it... pull it out with the old inner ring. There was a thread talking about a 3" conduit coupling.. and this was my substitute for that... but it is not needed.

enjoy




the tool in action pulling the suspect FAG bearing out getting ready to RMA back to Pelican... I'll bet it is still good... pulled on the inner race only.. probably only last 15 years instead of 25.

Old 05-13-2008, 09:47 PM
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for all following along... I'm sure the modertor hates me..

big discovery today - and I may be eating just a bit of crow..but maybe not.

I took the seal off one FAG bearing and this is what I discovered.

Yes, the seal grabs the inner ring but that is really not the sliding surface, there is another seal under that. Still the seal moves and I don't like that. Why did the FAG engineer say this was a standard inner ring slip seal? It does look like the seal underneath seals on the outside ring so there is a sealing there...

The seal slipping surfaces are between the black lip and backside of the red seal.

This could actually be a better bearing with more elaborate sealing (two levels). The only issue as mentioned is that fact that the seal rotates in grit very likely.

pictures.. let me know what type of seal this is....




another.. these a bit hard to get a good picture with my skills/camera



and here is a picture of the seal... grabs the inner ring and just rides along inside of the outer ring...

Old 05-14-2008, 08:43 AM
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ocd much?

Here is a diagram of how the FAG bearing seal works as far as I can tell.

I show where debris/water/etc. can build up... and maybe hang up the moving seal. There is a similar question re. debris build up at outside plate... this just shows how the bearing is pushed back to the stop in the arm.


Old 05-14-2008, 05:05 PM
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What great timing, or are these bearings all just reaching their life limit at once? I had my brake m.c. go out a few weeks ago. When I got into the rear end to install new brake lines and replace a torn cv boot I knew I had, I discovered a little wobble play in the driver side hub. So I ordered bearings from PP last week. Of course I had been reading all the posts I could find on this procedure. Sure enough I got the FAG brgs with the seals that spin with inner race. I thought , but then hcoles took one apart and maybe these are just fine. I don't like the idea of the spinning seals exposed on the engine side of the arm. But then I thought - the originals have lasted 20 years, so maybe these will only last 10 or 15? I'm going to continue with the installation. Thanks to all for all the great info & help.
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Old 05-15-2008, 05:32 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #107 (permalink)
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jclporsche,
thanks for reading along and comments...
Probably you will be fine, otherwise PP would have heard of early failures and pulled the FAG some time ago.
My concerns are still along the lines of the seal running very close to the arm and front plate along with the debris that can and does build up there.
Tonight I'll pull in the new SKF bearing with the more conventional seal arrangement.
Be sure to check on the back of the arm that you don't have a burr sticking out toward the seal. One of the puller parts I made - you can see in my picture - made a burr when pulling out the first bearing. This is why I recommend pulling on the inner race.
Old 05-15-2008, 05:44 AM
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hcoles,
I will check for burrs, clean meticulously, & load them in straight. These press fit parts can be easily damaged. It's really amazing to think of the forces this relatively small double row brg can handle with the size of those tires and the g-forces generated. Will get some pics to post of my mess tonight.
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Old 05-15-2008, 06:08 AM
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jcl,
I assume you are going to freeze bearing and heat the arm... that makes it very easy. I get the arm hot enough that it almost burns fingers.
Yes, it is really amazing the strenght of modern steel materials. When cornering and accelerating most of the weight is on one bearing in addition to a big part of the side force and this one bearing takes all that in stride.

When you look at the arm.. I'm thinking it isn't strong enough.. I wonder if race cars have trouble with stock arms.
Old 05-15-2008, 06:15 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #110 (permalink)
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FWIW, my bearings came from PP about 2 years ago, pretty sure they're FAG but I don't have any pics from that part of the assembly, not sure if they're this seal design. No problems so far.
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Old 05-15-2008, 06:35 AM
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jcl,
you may have figured this out.... when the nut is taken off the axle... it releases pressure on the two inner races and can make the bearing feel worn out when it is actually ok.

IMO - you can only feel for rear wheel bearing play when there is a good amount of torque on the axle nut... doesn't have to be 330 but likely 100 ft-lbs... when I torqued mine to this the play went away...
Old 05-15-2008, 07:49 AM
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hc,
Now that you mention it, the axle nut did come loose fairly easily. I used a 1/2" breaker bar with a 20" long handle. I barely had to step on it to break it loose. Maybe 100 - 140 lb-ft. But the hub was fairly loose, I would say that wheel had a good 2 mm of play when I held it top & bottom & lifted. So it is time for new bearings. The passenger side is tight, but I'm changing out both sides.
Didn't have time to work on it tonight. Will post on progress.
Anxious to get it back on the road...
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Old 05-15-2008, 09:49 PM
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interesting that the axle nut was that easy to get off... they should be put on with 330 ft-lbs.
In general term 1/2" tools really can't be used. I got a 600 ft-lb torque wrench with 3/4" drive and a 3/4" 32mm socket I ordered online for $12 or so.

I would say with 90%+ that the 2mm you felt was after the nut was off, right? That bearing may have been ok. For the other side consider checking the play with at least 100 ft-lbs on the axle nut... for that matter check it now before undoing the nut.
Old 05-16-2008, 04:59 AM
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No, it had play before I touched the nut. That's why I got into this area. I was just going to do the cv & brake work. Will see how it looks once I get the bearing out.
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Old 05-16-2008, 06:00 AM
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yes, please post what the bearing feels like after you get it out....
same for me - all started with a torn cv boot....
I would think some noise would come from a bearing with play like that...or that it would fail at a fast rate... but I don't know, just guessing. 2mm at the rotor edge is not much down in the bearing races.
Old 05-16-2008, 06:06 AM
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I installed a new SKF bearing... this is now the third time putting a new bearing in the arm.
Heating the arm and freezing the bearing works great - easily went all the way in until it hit the hose clamp to the old race. This time I installed all the brake hardware/etc. Then pulled in the hub... it is hard to start the hub straight... or at least it was for me. When I got it straight it was much happier going in.

Torqued the axle nut to 330 ft-lbs with a monster 3/4" torque wrench I got from work. Wife was on the brakes, son watching the gauge and me pulling on the wrench. The brakes just about can't hold the 330 ft-lbs.

Torqued the cv bolts to 60 ft-lbs.

Note - take a look and pre try installing the shock bolt to make sure it goes in easily without a shock. It is common that the threads get damaged or layed over a bit. You don't want to mess up the threads in the arm. I fixed my bolt with a thread restoring die.. 14mm. I bought a Master Thread Restoring Set from Craftsman - one of the best things I've bought - I think I only paid $55 or something like that. Has SAE and Metric. Anyway.. check the bolt and use anti-sieze.

Now down to why I posted this morning.

Here is a picture showing where the arm metal overlaps the seal and debris builds up in and around this area 360 degrees around the seal. The seal is close to the arm and I think the FAG bearing MOVING seal is even closer. This is why I went with the standard type seal.


Old 05-18-2008, 05:42 AM
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Didn't have a lot of time to work on it this weekend, but when I did I ran into another problem. Trying to pull the hub out of the bearing in the arm - it wouldn't budge. Using a 3/4" threaded rod with a 10 lb weight for impact. applied liquid wrench at the inboard end of the hub and let it set for a day. Tried it again the next day, no movement. So I decided to loosen the retainer flange bolts and pull the whole bearing & hub out of the arm. Probably shouldn't have done that. Now I've got to find a tool to get the bearing off the hub! Will see if they have something at work today.

The other thing I notice is some fretting at the contact between the axle shoulder and the bearing inner race. Is this small step (about 1mm) on the axle shoulder normal or has it worn that much? I haven't taken the other side out to compare yet.


It matches the inner race dimensions exactly. I hope I don't need to replace the axles. Can't afford it right now.
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Old 05-19-2008, 06:43 AM
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a bit interesting... when you pulled on the hub the inner races should have split and left the bearing (with one inner race) in the suspension arm... I'm thinking your arm is not grabbing the bearing very tight.
Old 05-19-2008, 07:08 AM
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I see what happened.. you loosened the 4 bolts and the whole bearing came out..instead of the hub with the one inner race. You could freeze the bearing and all that and heat the arm and slide it back in.. then hammer the rest of the way as you tighten the bolts.. when cool keep the bolts on and hammer the hub out.

headsup warning - the torque in Bentley for the bolts that hold the bearing plate is not correct. I think it says 34ft-lbs... that's too much for the small bolt. In any case check that.. something was wrong on that page re. torque. The shock bolts are 92 ft-lbs and the axle bolt is 330 ft-lbs.. you need a Big F Torque Wrench and a 3/4" 32mm socket. Also get a 4-6" or so 3/4" extension or you may have limited swing as you hit the fender.

Old 05-19-2008, 02:14 PM
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