C3 rear suspension question

[Yves Thaens]

Hi,

I'm posting this question for a friend of mine with a 1977 Corvette. He had problems with his rear bearings (left side) and decided to rebuilt the rear trailing arms. He pressed the right spindle out with no problems, but when he pressed out the left spindle the caliper mount bracket broke on one of the mounting studs. Now it seems impossible to remove the spindle because there is nothing to put enough pressure on the bearings . Hope I explained this right because this is difficult to discribe.

Any thoughts on this ?

Thanks

Yves

[Joe L.]

Re: C3 rear suspension question

Yves-----

I assume that he was using a "GM style", 3 point mount spindle press tool? If so, this is a somewhat common problem when such a tool is used. It's usually caused by failure to "square-up" the press plate so that it's perfectly perpendicular to the spindle. The GM tool, J-22602, is designed so that when used as-designed, it's pretty difficult to get into this situation. However, the aftermarket "copies" of this tool do not share these "fail-safe" features.

Another thing that can cause the caliper mount breakage problem when using the tool are spindles which "extremely stubborn" due to variety of reasons, especially a long time in-service without removal. For this type of situation, one needs to tighten the press bolt, "whack" the end of the bolt with a big hammer, and then repeat the process as many times as necessary. Sometimes, even this will not work.

Anyway, at this point I think that the only thing that's going to work is to remove the trailing arm, jig it up securely and solidly in an hydraulic press (without ever pressing against the trailing arm itself), and press the spindle out this way. I have seen it take over 20 tons of pressure to free some of these long in-service spindles; one usually hears a MAJOR "bang" when the spindle breaks free of the bearing inner race in the press.

I really don't think that he'll have any luck, at all, with a "spindle knocker" type tool (basically, a tool which protects the spindle threads and allows you to pound on it to impactively release the spindle). I've never seen one of these work for "stuck" spindles. Of course, it may be worth a try.

[Yves Thaens]

Re: C3 rear suspension question

Joe,

He's beyond the spindle press type tool since the caliper mounting bracket already broke. I was already looking at removing it with a standard press, but I have a little bit of a problem figuring out how to mount the trailing arm so that I can press out the spindle that is without pressing on the arm itself. I tried to put in bars between the arm and dust cover, but the bar i can get in is not thick enough to withstand the pressure.

Any thoughts ?

Thanks

Yves

[Joe L.]

Re: C3 rear suspension question

Yves-----

Yes, there's no doubt that the spindle press tool is irrelevant at this point.

As far as mounting the assembly in a press, you do need to use very stout "beams" to press against. I have done this many times and I recall that it was tricky, but it is do-able. However, it's been so long since I've done it, I've forgotten just exactly how I did mount it.

One thing that will help, though, is if you remove the spindle/bearing support assembly from the trailing arm. This can be done if you first remove the parking brake. This is also a little tricky, but it's commonly done. However, this is definitely NOT how I did it. I was able to support the bearing support while the whole thing was attached to the trailing arm. I remember, too. watching the pressure gauge on the press I was using go past 20 tons before it broke free.

[Michael H.]

Re: C3 rear suspension question

Yves,

There is another way to remove the spindle without removing the control arm. If you or someone you know is handy with a cutting torch, you can "slice" the inner bearing race without damaging the spindle. It takes a bit of talent but I've done it many times.

As joe mentioned, it's also easier to press the spindle out in a press without the control arm attached. You can either remove the four nuts as Joe described, or you can drill a hole in the spindle flange, between the wheel studs, that's large enough to fit a 9/16" socket. That gives you easy access to the four nuts. Once the nuts are removed, the assembly will be easy to remove and overhaul. The hole that you drill has no effect on the integrity of the flange and because it's so close to the C/L of the spindle, it shouldn't affect balance.

I think it's also possible to drill a hole that's only slightly larger than a 3/8" extension. If you can get the 9/16" socket behind the spindle flange, you can then attach it to the extension and remove the nuts.

The entire rebuilt assembly can then be reinstalled in the reverse order.

[Yves Thaens]

Re: C3 rear suspension question

Hi,

I was also looking at a spindle remover from Zip. Its a kind of nut that fits over the treads and that can be used to drive the spindle out with a hammer. Anyone used this and is it safe. In the explanation they state that the nut rests against the spindle shoulder.

Thanks for all the advice so far.

Yves

[Michael H.]

Re: C3 rear suspension question

Yves,

I've never used the tool that you mention but I suppose it can't hurt to try it. The problem with trying to hammer on the end of the spindle/tool is the limited amount of space with the assembly still bolted in the car.

Also, because the control arm is not "backed up" by something solid, most of the force/impact applied with the hammer is absorbed in the movement of the assembly when you hit it.

Also, heat may be helpful at this point if you happen to have a torch. If you wrap a small piece of sheet metal around the end of the spindle, it would be possible to heat the inner bearing race without excessively heating the spindle. A little heat goes a long way on tight bearing races.

I've never liked the design of this entire assembly. I still don't understand why it wasn't designed differently. Some method of removing the support should have been provided. Perhaps if the four support studs were installed the other way, threaded end inboard, it would have been much easier to service the bearings.

[Chuck R.]

Re: How dare you Mike!

To even think of referring to what the General has created as being less than a well thought out component!

From the minute I started on my Corvette journey, I've been keeping a casual "gee why didn't they do it this way" sheet..................... It's turning into a novel!

I didn't invest in a professionally machined knocker, but rather made a knocker out of an old truck tire iron. The knockers DO work, but having said that, free space to take a good healthy swing at the nut is critical.

Even then, the hammer has to be at the minimum a two pound peen type or larger (larger is better), it has to stike the nut squarely and the nut has to be re-checked after every strike to ensure that it hasn't loosened up.

I agree with Mike, that it is critical that the spindle assembly needs to be backed up somehow so that the energy of the strike isn't lost with the arm flexing in the front bushings.

Your right Joe, it sounds like a gun shot going off when the bearing finally gives it up in the press. You just can't top a twenty ton press for this type of work.

My two pennies worth.

Chuck

[John H.]

Re: How dare you Mike!

A special slide hammer also works well for this - I was at Masterworks yesterday shooting an article on trailing arm/spindle rebuild, and they have a VERY stout slide hammer they built specifically for removing spindles on the car, and it has about a 30# weight on it.

[Yves Thaens]

Re: Succes !!!!!!!

Hi,

I finally got it apart and i do want to share this with you guys. After looking at the tool that I saw for 20 $ I decides to fabricate something myself... this is how i did it.

I put the trailing arm with one end on the workbench en with the other on the press to level it. Then i put a steel pipe over the treads that just fitted over the treads. Then I started banging away on the pipe. I took quite a lott of pounding, but eventually it came out, undamaged (fortunatly...)

We should have thought about this earlier, that is , before we broke the caliper mount bracket with the damn press.

Hopefully anyone else with the same problem will have any use of this before he/she brakes something expensive like we did...

Yves

[Michael H.]

Re: Succes !!!!!!!

Great, it finally came apart. Not likely it would have ever moved with the control arm still bolted in place on the car. Too much flex.

I would definitely replace at least that inner bearing though. They don't like all that pounding on the race. It may still look smooth but it's not.