When you put pressure on the spindle to push it (or pull it) out, the pressure transfers to the inner bearing, inner race. The inner bearing inner race transfers the pressure to the rollers. The rollers transfer it to the seat, and the seat transfers it to the spindle support which is the "immoveable object" in this case. At the break-away pressure, the pressure of the tool over comes the press fit between the bearing inner race and the spindle, and the inner race slides off the spindle. This transfer of pressure is what can potentially damage the bearing.... and is why I never re-use them.

On assembly (as posted above), you install the outer grease seal, press the outer bearing onto the spindle by pressing on the INNER race only. This avoids any damage to the outer bearing.

After greasing the outer bearing and filling the spindle support to about 80% (100% grease will heat up, expand, ooze out & maybe blow the seal), you slide the spindle, seal, outer bearing, spacer, shim into the support (new seats already installed). Next, you slide the greased inner bearing onto the spindle until it stops and make sure it's not cocked (they **** almost every time). Now you press on the inner race of the inner bearing until the inner race, shim, spacer and outer bearing inner race all stack up solid. If you're using a press, you need to stop short of full pressure.... the 100 ft lbs of setup torque is a lot less than a 20 ton press exerts... and you can over-press the assembly. At this point, since you selected a shim to provide .001 to .002 endplay, the rollers & seats have not stacked up along with the inner races, spacer & shim. So you're good to go.... no possible damage. Use the nut to finish it off at 100 ft lbs. At no time during this process is there any pressure applied to the rollers & seats.

If you use the tool sold (Edit: the one that I have, not the newer design) to pull the assembly together.... you will put pressure on the rollers & seats. For this reason, I do not use any tool that works that way on assembly. I use a press, and press only on the inner races for both bearings.

I think that covers it.... basically.

Edit... there is one tricky part... the outer seal must be pried carefully into position avoiding damage in the process. I use a well rounded wide blade screw driver to evenly install the seal without damage.

 

As Gary noted... the setup tool allows you to trial fit with no pressing.

The factory procedure has you measure the endplay before you take it apart to calculate what the new shim should be. It's flawed just like their .008 endplay limit.

Before the setup tool was available, people used an old spindle cut down for a slip fit on both bearings.

 

Thats the reason for the setup tool. You only want to do it once.


I believe the tool used to pull together the assembly pushes on the inner race of the inner bearing.

Unless my thinking is incorrect the tool can be used to press on the outer bearing as well by only pressing on the inner race of the outer bearing. After knowing what shim is needed, use a couple of extra shims and slip fit an old inner bearing. The tool will push/press the outer bearing on the spindle and only apply pressure to the inner race. Since the inner old inner bearing is slip fit the spindle will come out with minimal or no pressure needed. Grease the outer bearing, ect... Take the new inner bearing with the corect shim(s) and use the tool to press on the inner bearing. No 20 ton press is needed.

 

My mistake, I can see that the outer bearing would get pressure on the pulling part but the inner one one does not, I agree that a sleeve for install would be a better way to press them on using the inner race. Thanks for the good chat on the topic!!

 

Not to highjack this thread but I'm rebuilding a couple of T arms now and have some pictures that I'm going to post on another thread.
Gary

 

Gary, that would be great, This is my first Vette, what a nightmare compared to the Nova's and Camaro's amoung plenty of others. I am amazed at the enginering for the time though.
Thanks

 

You may be right on the tool design... I don't know what everyone has in their hands. There are a few different designs out there. The point is, based on a long history with this spindle/bearing design, the general consensus among people who do the work professionally, is that it is a bad idea to use the roller/seats as assembly pressure points.


Also-
The inner bearing is not a slip fit.... it is a press fit just as the outer bearing is.

The reference to "slip fit" in my above post is specifically for custom engineered (turned down) spindles (or honed out bearing inner races) that do not require a press. When this is done, the outer bearing is never altered for a slip fit, only the inner bearing.

All factory C2/C3 rear bearings are an interference fit, requiring a press (or some sort of rigged up tool) for assembly.

Edit: if the tool pushes on the inner bearing inner race, but pulls on the outer bearing roller/seat during assembly, then it still can damage the outer bearing in the process. I believe that is how the tool works. Even if the outer bearing is already pressed completely on the spindle, when you tighten the tool against the inner bearing inner race, you are still using the outer bearing rollers/seats as a pressure point.

Edit: This is not how the -current- tool works.... I corrected myself in a following post. The tool I have is old, and does work this way, so I don't use it.

 

Tom454:
When I refered to a slip fit inner bearing it was in reference to pressing the outer bearing on to the spindle using the tool. This slip fit bearing is not permanent. By slip fitting an old inner bearing the assembly would not have to be pressed apart to get it off. After sliding off this old bearing, the new inner bearing could then be pressed on during the final assembly.


I agree that a hydralic press is a good way to do this. My problem is I do not have the floor space. The tool does a fine job when used properly and can be stored convienently with other hand tools.

 

OK, one final question.
The runout on the spinde is controled by the spacer and shim that separates the 2 bearings. Is the only thing controlling the movement of the inner bearing on the spindle due to the press fit of the bearimgs? Or does the inner half shaft flange press against the inner bearing preventing it inward movement?

 

Not quite understanding what yer sayin'...

"Slip fitting the bearings" means turning down the spindle where the inner bearing inner race rides on the spindle. So.... when you assemble it, you do not need any special tools.... just a socket & torque wrench.

There is a debate as to whether or not this is a "good" thing. I did it to my C2 just to see if the sky would fall.... and it did not.

I think (guessing), what you are saying is that you can hone out the old inner bearing inner race for a slip fit, and then use it during the setup phase, and finally use a tool or a press to do the final non-slip fit assembly?

If so, you may get a wrong dial indicator reading because the old rollers & seats will be worn. In this case, the distance between the two inner races will be less than the same distance if a new bearing were used in the setup phase. This would produce the wrong dial indicated endplay, and wrong shim selection.

?

 

Once the whole shootin' match is pressed together, the torqued nut exerts pressure on the washer & flange to stop the assembly from opening up or getting loose. The nut holds it all in place. That's why it requires a cotter pin.

 

OK, so the flange has to be torqued on to 100 ft/lbs in order to get the correct runout?

 

Not to "get" the correct endplay, but to maintain it.
Edit: When using the setup tool, the 100 ft lbs "gets" the endplay,
in final assembly, it just maintains it. Little confusing there.

I press the assembly together until I can feel the parts "stack up". I don't over-press it... I have found that when I "over-press" it with a 20 ton press, I loose about .001 endplay. That's a critical loss when you're looking for .001 to .0015 which is what I attempt (not .001 to .008). The setup tool (or old spindle turned down at both ends) relies on the 100 ft lbs to produce the value on the dial indicator. 100 ft lbs on the nut does not generate the same clamping pressure as a 20 ton press.

By the way.... the cheap 12 ton press at Harbor Freight works fine for ASSEMBLY, and it costs less on sale than the special assembly tool, and the press can be used for a lot of other projects. 12 tons is marginal for disassembly in some cases.

I have both a 12 and a 20 ton press to compare notes.
I used to have a 60 ton run by a hydraulic pump.... sold it with my machine shop business. That was a nice press, but didn't allow for "feel" which you need for this job.

Edit: The bearings you use during the setup step must be the ones used for the final assembly to maintain the correct endplay. You cannot "setup" with one bearing and then substitute a new/different bearing for final assembly.

 

Almost sounds like my previous post was not completely read.
The only way to know is by using the new bearings and the setup tool.

Here is what I suggested when using the Spindle Installation Tool that is sold to press the assembly together.
First, use the setup tool and new bearings to figure out what shim is needed to get the endplay correct.
If the bearings are then pressed together with the Spindle Installation Tool, it will press the outer bearing by applying force to the rollers/cage. According to what was stated that is not the best thing. If a couple of spare shims or washers are used when the assembly if pressed together, the force will be applied to the innner race of the outer bearing. Now the outer bearing is done but there are too many shims installed. This is where using a slip fit inner bearing comes into play. If an old slip fit bearing was used, it will slide off. Since endplay was already done with the new bearings, install that shim along with the new bearing and press it on with the tool.
Endplay is good since it was checked with new bearings and shimed accordingly. No force was applied to the rollers/cage. The only additional item(s) needed were a few spare shims. Chances are a package of shims will be needed when checking end play. The only thing questionable is how strong the spacer is since it being used to press the outer bearing on.


To install the outer races of the bearings in the carrier, I grind the old races down. After getting the new race started I place the old race on top of it and hit on it instead of banging on the new ones. They sit flush and spread the load more evenly. The reason for grinding it down is so that it comes out esaily after the new one is fully seated.

 

I read the posts several times.

Anyhow... let me see if I finally understand your method....

1) Use a setup tool to determine proper shim/endplay
2) Hone out the inner race of an old inner bearing
3) Install the outer seal on the spindle
4) Use the slip fit junk inner bearing and the "tool" to install the (new)
outer bearing on the spindle... using the rollers/seats as pressure points against the outer bearing seat insert.
(possible damage to outer bearing/seat)
3) Remove the temporary slip fit inner bearing, use the tool to press the new inner bearing on the spindle (no damage to inner bearing).
4) install washer, nut, seal, flange, etc. torque to 100, install cotter pin.

Is that it? DId I get it right this time?

 

Here are a couple of web sites showing how to change the bearings. Lots of pictures!

http://www.corvettefever.com/howto/36458/

http://www.montygwilliams.com/rearbearings.html

 

mandm1200 and I have been sharing notes off line... we were just having trouble finding the right words... so... we flipped a coin, I lost, so I had to come back here to flog the horse-

I believe with one version of the assembly tool, you can successfully "pull" the spindle & bearings together without putting stress on the rollers & seats. The key is that there must be enough tool working distance to install the tool with both bearings in their unseated position, and then pull them together without using the rollers/seats as pressure points. I believe the tool on Montys web page is designed that way- at least it looks like it to me. If not, it can be done as a two step process using a temporary slip fit inner bearing & extra shim (see below).

In sum...
(shield/pin installed)
The correct shim is selected using a tool.
The outer bearing is greased & placed in the support
The outer seal is installed in the support
The spindle is started in the outer bearing
The spacer, shim, and grease are installed on the spindle, inside the support
The inner bearing is greased and started on the spindle
The flange/tool is installed on the spindle (per tool instructions)
The tool is started on the spindle, facing on the flange, the flange facing on the inner race of the inner bearing (the flange part I'm not sure of, apparently part of the tools instructions)

The tool is turned to pull the inner bearing onto the spindle using the inner race as a pressure point.
As the tool is tightened, the spacer & shim stack up, and one or both of the bearing inner races are worked against each other as the two bearings are pulled toward the center, eventually, leaving the endplay as initially measured, having exerted no pressure on any bearing rollers & outer seats

This seems feasible to me.... I do not have the tool as shown
One of the tools I have does not work this way, and relies on the outer bearing rollers/seat as a pressure point.... so I never used it.

Two step process:
There is also the option of using an old slip-fitted inner bearing (or facsimile) to first pull the spindle into the outer bearing, and then substitute the (new) press fit bearing to complete the job. This would make it a two step process. The slip-fitted inner seat would stack up solid immediately with the shim, spacer, and inner race of the outer bearing- and you can then pull the spindle into the outer bearing without messing the rollers/seat. In this case, since the old bearing may not be dimensionally the same as the new bearing to be used, you should place a second shim onto the spindle temporarily while you pull the spindle into the outer bearing. This will assure a stack up >= your endplay which will keep the inner bearing rollers from prematurely hitting the seat in the support. Then remove the slip-fit bearing & extra shim, and install the correct inner bearing.

Now, if I still don't have it right, time to shoot me.

Typically, I would just buy the (new version) tool to verify it all myself, but funds are low right now. It'll have to wait.

 

Tom, I've been following this thread with interest because I also used the install tool.....the newer version I guess. It's been awhile so I'm relying on a foggy memory, but I believe your version of how that tool works is correct.
As I recall....on final installation.....the spindle is inserted through the outer bearing....the inner bearing is started from the back side. As you tighten (turn) the nut on the tool it pulls both bearings toward the center via the inner races. There is never (the way I'm thinking) any pressure between the outer races and bearing rollers.
I was pretty impressed with how smooth the feel was when pulling the bearings together. No popping, groaning, etc. just very smooth turns until the stack makes up.
Gary gave me a lot of great help and moral support when I did mine so I am eternally greatful to him.