Is this CV joint bad?

[Don Plumley]

I'm replacing the boots/lubing the CV joints on my 87 3.2 - because I found a torn boot. Both half-shafts are now on the ground. That part was fairly easy once I got the big wrench and realized I had to remove the lower shock bolt.

The outer joint with the torn boot was clean and well greased inside. But I have some difficulty rotating it through 360 degrees. Unlike the other axle where I can use my hands and roate the joints through any angle, the best way for me to describe it is "hard notchy". It grabs and releases and the axle shaft (not the stub axle) bangs into the sides of the housing.

[Note: The 87-89 axle assembly is different than other years. The outer CV is not user serviceable, it's somehow attached to the stub axle. I attached a couple of photos so you can see.]

I've not flooded it with solvent to look inside yet, but after wiping out much of the grease, I don't see anything out of the ordinary. The other side of the same axle was very smooth.

I'm afraid I already know the answer here - new axle assembly required - but wanted to ask the forum for help/confirmation of my situation. Ouch, right in the wallet. Hopefully Parts Heaven has one for sale.

[82SC]

when they are BRAND new then they are also very notchy when they are broken in they should be like butter...

make sure your CV is not cocked at a wierd angle or you didn't impact one of the balls in a funny position....I'de get it back to neutral...then try moving it around...if you feel resistance I'd say it is ready to be replaced

also yours are a little different then the 82SC ones I am familiar with...but I dismantled mine...took all the balls and races apart...and checked all the surfaces etc...for discolor (OK) pitting (not good) cracks (BAD)

if you do dismantle be sure to keep track of how the races orient to each other and which ball goes where

MJ

[Early_S_Man]

Don,

I haven't repacked that style CV, but I don't think you can make a decision until it has been thoroughly cleaned/flushed of any sand or dirt, and then repacked with Swepco 101 or Valvoline #986 SynPower Synthetic Grwease with moly. I'm sure it will improve, but ... it certainly won't hurt to try the repacked axle on the road before making a replacement decision.

[Don Plumley]

Warren/MJ,

Thanks for the replies. Three of the four joints are like butter. I've pulled the axle in and out. Then try to rotate the joint around any angle is very, very difficult. The axle just jumps and bangs into the housing.

I agree, I should get in there with some solvent and see if I can see anything visually. It's tough trying to a) line up a replacement (used) axle; b) hope that it is okay; and c) not repack this mother and have to take it out again to replace. I want to do this once....

...sorry, I'm just a little demoralized.

Thanks guys.

[Oldporsche]

Looks like another Porsche better idea that really isn't.

It would be interesting to see if thes unit is replaceable by taking off that tin shield. Or maybe replace this with an earlier unit.

Good luck,
David Duffield

[jmohn]

Yes, I also think it was a poor design decision to make the outer CV joint non-replaceable (BTW it's a "friction" weld). It's been my (admittedly limited) experience that any "notchy" feel to the joint is bad, new ones don't, to my hand, feel notchy, just stiff. If it were mine I'd replace it.

Good luck,

Jerry M
'78 SC

[Wayne 962]

Replacing it with a used axle is a very bad idea. How will you know if the used one is good? These are basic wear parts on the car - you wouldn't think of replacing your brake discs with used ones? Any used axle will wear out in a very short time (depending upon the number of miles on it - something that is nearly impossibly to figure out for sure).

I never install used parts on areas of the car that contain principle wear parts...

-Wayne

[1.2gees]

I agree with wayne, afterall you never know if the used axle you buy is about to look like this:



This is what you don't want to find if you take it apart:

http://boards.rennlist.com/upload/DSC0000004.JPG
http://boards.rennlist.com/upload/DSC0000005.JPG
Ahmet

[Don Plumley]

Wayne - I agree with you in principle. My idea is I can pick up a used axle and do the rebuild - since I'm doing the other side anyway.

Does this change the equation or would you still get a new axle assembly?

[Superman]

Dirt is as big an enemy to these parts as anything else. Torn boots commonly mean a thrashed CV joint, unless you catch them in time and remove ALL dirt, repack and re-boot. MY guess is that dirt is what is making that CV act poorly. The parts in a CV joint are machines so perfectly, that there is no room between them for dirt. Your only hope for saving this joint is, like Warren says, get it perfectly clean and repack. Getting these things perfectly clean is pretty hard unless you disassemble.

Still, worth a try. Beyond that, a new shaft is needed, or an old shaft with new CV joints on it. Used CV joints are not the way to go.

[Kurt B]

Just looking at that gives me a stomach ache. I hated dealing with my cv joints.

I know the later ones aren't serviceable in the outer, but you really need to take that copper holder off and have a look inside. I don't see a picture of the bearings and bearing cage. The cage is pretty thin. It's easy to see how it will wear and break over time and it needs to be inspected for cracks. When it goes, it just goes and your bearings will end up in the ground like mine did!

Here's a pic of my cv joint. You can see the inner part that connects to the shaft and the outer part. What's in pieces is the cage that holds the bearings.
Dangit, disaster strikes.

[jwill911]

Don,

I've bought brand new OEM Lobro axles for my `87 Carrera for $155. I would not mess with the mess of rebuilding or lack of confidence using an used axle would cause me. When I'm driving my car close to my limit, I don't want to worry about that used or iffy part I saved some money on. If interested in where I got them PM me.