CV Rebuild questions

[NutmegCarrera]

So I've had some noise from the rear of the car. 1985 911.
Car has 110,000 miles, and was very much untouched when I acquired it. Not much in the way of maintenance records. Having been all around the brakes and suspension, I can say that not much appears to have been touched - particularly in the recent past.

CV boots appear good, and I doubt that the shafts have been removed from the car, ever.

So my questions revolve around:
1. Is there any point in attempting to remove, disassemble, clean and pack with new grease?
2. If the balls / races appear clean and free of pitting, galling or apparent heat marking (discolored), is a rebuild acceptable?
3. Assume #2 is true, I'm thinking that grease is just used up or ineffective after 25 years.

These questions are aimed at whether it makes sense to pull the shafts and put any effort into dissecting and attempting a rebuild, or should I just buy complete new ones and bolt in. I would prefer to save the money if there is a snowball's chance that mine can be saved with maintenance.

If that's the case (rebuildable), do I need to get an Oetiker crimping / cutting tool to deal with the boot clamps? If so - is there a particular size? Also - what parts can be re-used? I have the 100mm diameter variety of joint. I have read that the bolts can be re-used. I believe there is a gasket needed, along with new boots and new grease. Any additional pointers here?

I understand that our host sells the proper grease. What about the best solvent for cleaning the joints? Do they need to be completely disassembled, or is there a washing method that does not require complete disassembly?

Finally, if they need to be disassembled - does each ball need to stay mated with the two pieces it orignally fit between?

These are probably very specific and anal-retentive questions, but being on a shoestring budget - I'd like to rebuild if possible. And, if this can happen - would prefer not to waste a bunch of time in the process (only to need to buy complete new cv shafts/joints to boot. (No pun intended).

And, what about the hub bolt that requires 300 lb-ft to torque it down: Does this bolt and/or the washer that it seats against need to be replaced?



Thanks in advance for any feedback.

[porterdog]

FWIW I sent the rear halfshafts from my '90 C4 to CV of Ocala for inspection/rebuild. It was $150/side, plus shipping (about $50 each way). They disassemble, clean, polish, regrease, reball, and reboot.

I had some discernable play, and my inner boots were shot. No one had remans in stock, and the price of new ones was frightening.

I chose CVO because they claim to *polish* your races, vs. the grinding that many rebuilders use. This is better because the surface hardening isn't removed. They'll also install new balls, but IIRC they said the largest they'll go is .003" over spec. Mine took .001" over.

Turn time was a couple days, not including shipping. I'll use them again, no question.

[2.70Racer]

The removal and inspection of CV's have been covered in detail many times. Search CV's or constant velocity.
I would at least replace the rubber boots, clean and relube the CV's and reverse the axles.
The CV balls wear the track in one direction. If they haven't been apart and reversed already, reversing the CV's will put the balls working on a unworn surface. This is an old school fix.
You will need new socket head bolts and schnoor washers torqued to spec.
IMPORTANT: Read up on the previously posted info.

This has been covered in depth by folks that know.
There are different CV's and bolts used throughout the years.
I think Porsche made a change mid 1985 so be sure to check your CV's.
The Torque for your bolts should be 35 ft/lbs. Older larger CV bolts need 65 ft/lbs.
There is lot's of bad info on the torque so be careful.
Recheck the torque on the CV bolts after 50 miles or a couple days driving. Which ever come first.
You do not want an axle coming loose. It will ruin your day, big time. This is serious work.

[HawgRyder]

Doing the work yourself is OK..but...please use "clean room" environment to do the job.
If even one speck of dirt gets into the CV joint...you could grind the joint to junk in days.
I have seen some supposed "repair" places and the filthy benches they work on...it makes the hair on my neck stand up....LOL.
Bob

[Shadetree930]

Save yourself a lot of grief and aggravation. Just buy new half axles. You can thank me later.

[NutmegCarrera]

Shadetree in SC:
Your line of thinking is what I typically do, but I often second guess how much cash I leave on the table.

Lots of good advice given here - I appreciate all of it!

I'm still curious to see what these things look like once I take them out.

Thanks all.

[gtc]

1. Yes 2. Yes 3. Yes

If more than one or two of your joints has pits in the bearings, just buy new axles. The cost of a couple CVs plus all new boots, bolts, lock washers, and gaskets comes very close to the cost of two new axles. Cleaning and repacking them is a mild PITA.

You don't really need the crimping tool. You can crimp the new clamps with a pair of pliers.

Also, you don't need to remove the rear axle nut. Just unbolt the CVs from the inner flange. (assuming your car is an early '85 and you do indeed have the 100mm CVs)

[Superman]

Originally Posted by 2.70Racer

The removal and inspection of CV's have been covered in detail many times. Search CV's or constant velocity.
I would at least replace the rubber boots, clean and relube the CV's and reverse the axles.
The CV balls wear the track in one direction. If they haven't been apart and reversed already, reversing the CV's will put the balls working on a unworn surface. This is an old school fix.
You will need new socket head bolts and schnoor washers torqued to spec.
IMPORTANT: Read up on the previously posted info.

This has been covered in depth by folks that know.
There are different CV's and bolts used throughout the years.
I think Porsche made a change mid 1985 so be sure to check your CV's.
The Torque for your bolts should be 35 ft/lbs. Older larger CV bolts need 65 ft/lbs.
There is lot's of bad info on the torque so be careful.
Recheck the torque on the CV bolts after 50 miles or a couple days driving. Which ever come first.
You do not want an axle coming loose. It will ruin your day, big time. This is serious work.

The above advice is good.

FWIW, I have inspected a fair number of CV joints over the years, and rarely find one in "new or nearly new" condition. They are all worn, in my observation. Sometimes the wear and pitting is minimal, but it is rare to find a used CV joint with no pits. Yes, I have reversed their position and put them back into use. But today, it would be my preference to simply replace them with new. It so happens that the cost of a new boot for my car is a substantial proportion of the cost of a new joint that comes with the new boot.

Once renewed, if somebody wanted to go to the trouble of disassembling and repacking them every 2 years, they would probably live a long time.

[DSPTurtle]

Umm... the rebuild kits (with grease) are anywhere from $8 to $30 per end (you need 4). That is way cheaper than new stuff. The hardest part of the whole job is making sure you don't strip the bolts while taking them out. Brake cleaner and hit the tool with a hammer after inserting it in the bolt.
This is one of the easiest, but dirtiest, jobs you can do on your car. I have rebuilt about 3 or 4 different sets of axles. This is not rocket science and they will work just fine. And if they don't, your are only out about $50.
Go for it and have some fun with it! Post lots of pics.

[efhughes3]

I think the money spent to just replace is money well spent. The good lord knows I'm not afraid to wrench on my car, but rebuilding CV's is a project I'll pass on.

[NutmegCarrera]

Good advice, guys - and all is well appreciated.
I love the idea of posting lots of pictures. Nothing better than used & dirty lubro-moly grease (25yrs worth) and a digital camera. Perhaps my sexy assistant will accompany me in the garage and pull shutter duty. Probably not...
However, I may just get after the cleaned up parts in return for all of the good advice. Might not be for a few weeks, though. Have to finish yard work, winterize yard equipment, etc...

Thanks again guys.

[chongito-blanco]

I just went through this with my 85 targa my C-V's didnt seem to make any noise but i had the powertrain out and the axles looked like hell. so i completely took the cv's apart hot tanked them and inspected them one of cv's and i cant remember if it was right inner, left inner etc.ect. had so much play i couldnt beleive i was driving around with something like that and was blue from heat exposer. the other 3 had a little more play then most people would tolerate. anyway i love to expariment so i lubed them up with generic cv grease installed them and now i have a clunk going around corners. anyway i purchased 2 complete used axels at the pomona fairgrounds and noise is gone.