G series CV joint install

[AC78]

I thought i'd do a post on the latest SC project keeping me off the road.

Recently I noticed that one of my inner CV boots had split and allowed grease to spray my entire inner wheel well and everything in the vicinity of it.
I figured that while I was replacing the boot I may as well inspect the CV joints, being that I could find no record of CV work ever being done on my car.

And what's the point of replacing 1 boot when the other 3 could go at any time right?  Same with the CVs - check all 4.

Here's a tip before starting on this project.  The CVs are held in place by allen head bolts, which after many miles are usually filled with gunk.  Clean the heads out thoroughly before attempting to unscrew.  These heads round off easily if your allen key isn't sufficiently bedded into the bolt.  I had to use vice grips on one of the bolts and it was a scary moment wondering if it would back out or not.

Once the axle was removed I discovered a decent amount of pitting on the inner CV, and consequently all the other CVs, so nothing to do but replace them all.

Lately I have been buying all my parts from Performance 9, which I have found to be well priced and comes with stern, no BS advice from Stan Adler.  I highly recommend Stan for your next DIY project.

You don't need any special tools for this job except a decent set of circlip pliers.  A very solid circle prevents the CV from sliding off the axle, so don't think you can do this job without them.  I also used an impact wrench to remove the stub axle.  You could do the job with the stub in situ, but it's way easier to have it out and on the bench.

Before going any further you should read this tedious but worthwhile Pelican thread, which discusses the intricacies of CV joint assembly and the damage that can be inflicted if they unscrew at speed.  It makes for some scary reading, so get familiar with things like schnoor washers, kidney plates, bolt lengths etc.

http://forums.pelicanparts.com/porsche-911-technical-forum/222537-reconstructing-constant-velocity-cv-joints.html

On that note, you should go to your specialised fastener shop and get all new bolts and washers. I got 24 new bolts and schnorr washers for less than $30, bargain!

There are several videos on Youtube which show you how to repack Porsche joints.  It's easy, but wear gloves.  The Loebro joints I got from Stan came with grease in packets which are designed to easily pack a joint.  The last time I packed a joint was at an ACDC concert, and this didn't turn out nearly as messy.

The finished axle:

Before reinstalling the axle the mating surfaces should be as clean as possible, particularly on the inboard side.  Same goes for the bolt holes.  I discovered these mini pipe cleaners at my local gun shop, and they are perfect for cleaning out old grease and grime.  I then finished off with alcohol and ear buds to get the holes perfectly clean.

What isn't shown in these pics is the thin gasket that goes between the CVs and the inner and outer flanges.  Problem is that these gaskets compress after a bit of driving, causing the axle to become loose at either end, so after you've done a few miles you need to retorque the bolts again.  

This is a satisfying and fairly simple job, and worth doing if you've got CVs of unknown history in your car.

Cheers

[MFX]

The only thing I would want to make sure about, is that the new bolts you got are the same hardness as the ones that are recommended (I have no idea, just a caution).

[LeeM]

I did that not long ago. Fun job....not! Messy as f...

 Jeff is right. Must be high tensile bolts or they'll snap pretty easily. Another tip is to take the circlip off in a box or with a rag so that it doesn't ping off into oblivion

[Zelrik911]

When you get the new CV from the suppliers, make sure it is assembled correctly. Dont assume that the way it comes out of the box/packet is right.

I had 2 where the inner was in backwards & the thrust side was opposite to where it should be.

Its not a big deal to swap around the inners as I always pull them fully apart to properly cover each ball in grease, anyway - but I am glad I noticed this when I assumed the new CVs would assembled 'right'. 

IMO the best CVs are made in Japan. I do not trust any Euro brand anymore as the traditional 'good' brands are sneakily made in Sth America or China or (gasp) India. 

[81SC]

Regarding the quality of the metric cv bolts discussed above, proper name of these bolts is socket head cap screw, a generic name is Allen head bolt.

If you buy a good quality metric socket head cap screw from a manufacturer like Unbrako, usually the grade of these cap screws are 12.9. But there are some low quality socket head cap screws on the market, that have a grade of 8.8. The grade is always stamped into the head of a quality cap screw. 

Personally, I would not use anything but a 12.9 grade cap screw in this application.

[AC78]

[MrRPJ]

12.9 is perfect. same grade used on most brake parts, 10.9 is usually used on suspension as it "flexes" a little more

[LeeM]

12.9 is perfect. same grade used on most brake parts, 10.9 is usually used on suspension as it "flexes" a little more

 Good to know, thanks mate