cv joint diagnosis

[stevepaa]

tried to find other threads but this new search engine stinks.

Anyhow, 1992 with 160kmiles, repacking cv joints and they sometimes get stuck when I rotate them. Also looks like one time the axle had a steep angle and dented the brass colored cover.

So how does one know when the cv is bad?

[island911]

Steve, they click click click when they're getting really bad.

You -can- disassemble them and check for pitting in the bearing races.

It is usual, when wobbling them by hand, that they seem to bind, so dont sweat that.

fwiw, my 81SC CV's are OE . .date stamped 81. . .though much lower miles.

[RoninLB]

Originally posted by stevepaa

Also looks like one time the axle had a steep angle and dented the brass colored cover.

maybe the dent happened when the rear was jacked up ?

[stevepaa]

Thanks guys. I put boots on them and use them.

Good idea on the dent.

[Nine9six]

Originally posted by RoninLB
maybe the dent happened when the rear was jacked up ?

RonninLB,
Are you suggesting that when the rear is raised, that there is insufficient clearance between the outside CV boot flange and the half shaft that runs through it?

The reason I ask, is because I have not found this to be the case. I believe the rear shocks, even at full extension, would not allow the training arms to extend to the point where the half shaft comes in contact with this boot flange. The reason I say this is because when I replaced mine, the last portion of my install was to zip tie my CV boots in their respective locations. There was pleanty of clearance between the half shaft running through the boot flange, while the rear of the car was on jacks, and the suspension was at full extend position.

I was led to believe that the outside CV boot flange can be damaged, if the inside CV joint (connected to the trans) comes apart. I have read quite a few threads where guys thought they lost their trans; when in reality their CV joints came loose from the trans. The initial flinging of the half shaft is what usually creates the the dent in this CV boot flange.

P.S. Just try sourcing this part by itself...Its not broken out as a separate piece in the PET, nor is it available through any Porsche dealer, our host, or Parts Heaven.
I was forced to buy a used half shaft to fix my damaged flange. Also, sourcing a larger (108mm, CV jointed turbo) half shaft is a little more difficult...

[RoninLB]

Originally posted by Nine9six


I was led to believe that the outside CV boot flange can be damaged, if the inside CV joint (connected to the trans) comes apart.

that sounds good to me.. and maybe the shock was disconnected for some reason with the CV's connected as when lowering the rear?

also, some guys safety wire their CV joint bolts.

[island911]

Originally posted by RoninLB
..

also, some guys safety wire their CV joint bolts.

fwiw, I find that installing the bolts dry, and torqued works just fine. I do recheck them after 100 miles or so (too many horror stories here, I supose) --no problems ever.

Anyway, my speculation is that people are letting that CV grease cause them problems with the bolts.(keep the bolt head contact surfaces clean) ...and maybe one or two are pinching a mis-set gasket (that would give the bolts a chance to loosen as well, I suspect)

We've got mechanics everywhere putting the CV's back as OE (no safety wire, schnorr washers. . . ) w/o issue. So, seems the smart money is on simply paying attention to putting it all back together cleanly. YMMV

[Nine9six]

Originally posted by RoninLB
also, some guys safety wire their CV joint bolts.

Yep...I took the path as stated by island. I also cleaned both internal and external thds and added blue loctite and torqued to spec. After 500mi and re-checking the torque, all bolts are still torqued to spec.