Confirm my "Bad Clutch" diagnosis

[RichardGozinya]

This morning on my way to work I was cruising about 40, I hit the gas not too hard to accelerate and heard 3 klump klump klump, 15 seconds later the car seemed to not be in gear. I pulled into a parking space, the car seems to go into gear, when I release the clutch I hear a faint grinding/rubbing noise and get no movement. Do you agree that my car is a candidate for a clutch job now?

[Grady Clay]

A CV joint may have become detached.

Reconstructing Constant Velocity (CV) Joints

Best,
Grady

[pcar9119]

Yep. Sounds like an axle. It happened to me racing a Camaro down the highway, just more violent thumps!

[Joe Bob]

Drive side CV unless you have LSD....usually the passenger side. On my SC< I found it easier/cheaper to replace the whole axle. Ask for Eric, PMB Performance: Online Parts Catalog (801) 674-3669

Best to replace both. My other side went inside of 300 miles.

[RichardGozinya]

Here are a couple of pics of the results:

Drivers Side:


Passengers Side:


I didn't have a jack large enough to get the huge jack stands I bought underneath the car. I'll have a jack tomorrow. Am I correct in thinking that when the car is in gear on stands that the axles should rotate if the clutch is indeed good?

If the axles are rotating, should I just tighten the bolts and torque them properly, or should I remove and rebuild the axles? What should I look for when I do an inspection?

[RichardGozinya]

Here's the passenger side picture.

[Grady Clay]

Yikes!

I suspect someone didn’t tighten the CV joint bolts properly.
There is also the widely held opinion that the CV joints are under-sized - design flaw.
Porsche up-graded the axles to the (earlier) 108 mm CV joints in about ’86.


I would remove both axles and stub axles and clean and inspect everything. The threads and mating surfaces are most important. Replace all the bolts and Schnorr washers. This is a good opportunity to replace the boots and grease.

When you reinstall, make sure you don’t get grease on the bolt threads or mating surfaces. Most important – re-torque the CV joint bolts after a few hundred miles and periodically after.

Read and study the thread linked above.
While long, it contains a lot of valuable information and links.

Best,
Grady

[billybek]

Originally Posted by RichardGozinya

Am I correct in thinking that when the car is in gear on stands that the axles should rotate if the clutch is indeed good?

If the axles are rotating, should I just tighten the bolts and torque them properly, or should I remove and rebuild the axles? What should I look for when I do an inspection?

What you will most likely find when the car is on jackstands, is when the car is in neutral (and the cv's are bolted up tight) is that one wheel will spin and the other should spin in the opposite direction. I wouldn't run the car on the jackstands unless you are very confident that it won't come down on its own. (remember Ferris Bueller!)

You probably have it licked by getting your CVs bolted up properly. There are a ton of threads on this if you do a search.

[RichardGozinya]

Grady,
Thanks for the replies, I'm ordering boots and grease now. Do you agree that this problem is the likely culprit to my klunking and non-movement?

[Mattcamp]

The klunking and no movement is because the bolts backed out.....it has nothing to do with boots or grease.....although it's never a bad idea to service your CV's. It's obvious from the pics that the bolts backed out so far that they aren't even in the hub anymore....I can't believe that the axle is still in line with the hub.

[Paulporsche]

Grady,

Would it be a fairly safe assumption that if someone's CVs were replaced in the last 20 years or so, that they would be w/ the 108mm versions? Were the smaller
ones discontinued?

[David]

The husband of a woman I work with had a similar problem. He thought it was the clutch so he parked it for 5 years!!!!!!

I told them I'd take a look at it. 30 minutes later I tightened the CV bolts and it was fixed. Unfortunately by leaving it parked for 5 years, the CIS system was crap, along with the fuel tank and fuel lines

[dshepp806]

WOW,...look at that sheeit!!!!!!!!!!!!!!!! I'll be checking mine THIS weekend.

Best,

Doyle

[McLovin]

Originally Posted by RichardGozinya

Grady,
Thanks for the replies, I'm ordering boots and grease now. Do you agree that this problem is the likely culprit to my klunking and non-movement?

Based on your use of the words "likely culprit" and ordering boots and grease, I don't think you are clearly understanding the responses.

If you look at your pictures, you can clearly see that the bolts are coming out! The pax side has one visible coming out, the drivers side are all loose.

This is not a "likely culprit." This IS the problem. Your driver's side axle is no longer connected.

[Mattcamp]

Originally Posted by McLovin

Based on your use of the words "likely culprit" and ordering boots and grease, I don't think you are clearly understanding the responses.

If you look at your pictures, you can clearly see that the bolts are coming out! The pax side has one visible coming out, the drivers side are all loose.

This is not a "likely culprit." This IS the problem. Your driver's side axle is no longer connected.

I think you have it backwards.....although it isn't very easy to tell. I think the passenger side is no longer connected and the drivers side is just starting to come loose. Check it out again.

BTW....I love your response. Here's mine.....

Go get a damn allen socket set.....tighten it.....and drive off smiling. Then get the grease and the boots and plan a weekend of some serious beer drinking and don't forget the rubber gloves. This job is messy at best.

[McLovin]

Post #5 says "drivers side" and those are all backed out.

Anyways, I'm with you. The boots all look fine to me, I'd just clean everything up, look at it closely, and if everything checks out I'd just make sure the bolts and bolt holes were cleaned out well with brake cleaner (or whatever), tighten those bad boys down and take off.

I would check them every now and then to see how they are going.

You could never go wrong with Grady's more thorough suggestion, though. But I'd first try a a "clean and tighten" because they may have backed out because some mechanic simply forgot to torque them down well.

[notmytarga]

I had a similar experience (mine came off the tranny) - diagnosed it before I rolled to a stop. It helps to be your own mechanic. If it happens again I will drill and wire those suckers.

[RichardGozinya]

I've made good progress, got the passenger side axle removed and it looks fine, all the mating surfaces are not gouged or scored. All the bolts are likely stretched, they all have flat threads near the tip, is this indicative of damaged threads on the wheel hub as well? 3 bolts are straight with flattened threads, 2 are bent with flattened threads, and one sheared off.

I'm going to remove the sheared off bolt tip with a left hand drill today. How would I judge if the threads on the wheel hub are still good? Can I use transmission side bolts to see if they go in and out easily?

I have also cleaned a large amount of grease that came out, should I put some more grease in the wheel end of the axle, it looks a little low.

I've ordered new bolts, gaskets and grease, but I couldn't find washers.

[TechnoViking]

Uh oh. Looks like the much-touted schnoor washer "upgrade" failed to keep these bolts from coming lose.

In my humble opinion, re-touring these bolts after driving a while (recommended in the factory manual) and then again every so often (recommended by me) may be more important than adding washers.