G50 Carrera CV issues...

[Rick Lee]

The longer my Carrera sits for sale, the more money I have to pour into it. Yesterday we replaced the starter and while she was on the lift, I immediately saw a totally shredded CV boot.
It looked almost as if someone had done it intentionally. I keep pretty on top of this car's maint. needs and was surprised by this one. Anyway, the passenger side is showing tiny signs of cracking. So I might as well just replace them both and be done with it.

So my quesiton is - if I just buy the entire enclosed assemblies, how do I install them? Obviously, inner flanges are easy. But I think they changed around 1985 so that the outer flanges are covered and the bolts are inaccessible. Is this an easy bolt-in job (nothing on my cars ever is).

[Rick Lee]

BTW, in the second photo you can see how we did a partial tranny drop to get to the upper barrel nut on the starter. I'd really like to know how someone pulled this job off (on a G50) without lowering the tranny. Of course, we wired it wrong the first time and had her all buttoned up before we had to pull it all apart again and track down the problem. I think I'm a real expert in G50 partial tranny drops now.

[ChrisBennet]

To change the outer boot, you remove the inner CV and slip (the outer )boot over the inside end of the shaft. Brand new shaft assemblies for these cars are ~$200 ea.
-Chris

[89911]

I just changed my starter on my 89 G50 last week and I cannot see how someone could change that bolt. It took me 10 minutes of manuevering just to touch it. The partial tranny drop actually took only about 20 minutes and was easy. On my brothers 87, some garage or PO actually went to the back of transmission hub between the two rear seats, lifted up the carpeting, and cut a window through the sheet metal to get to the top nut. Even with the tranny drop, I still needed all my extensions, a universal swivel, and a braker bar to get that nut loose!

[VincentVega]

Hmmm. I just had a bad outer boot on my 87. I couldnt find the outer boot for sale and read in Waynes 101 book you cannot replace just the outer boot. New axel fixed the problem, but at ~$200 I was not a happy camper.

[RickC]

If nothing else, the new axles are easy to deal with. Do a search for a thread about 3 months ago.

Short story is - get a 3/4 driver & pipe for the stub axle nut (around 340lbs of torque). Undo this bolt with the car on the ground so it doesn't fall on you (that's a good deal of torque). Put on new allen key bolts rather than the star thingies that come with the axles. You have to unbolt the lower shock to pull the old ones out (either Bently or 101 doesn't mention this, but it's true nevertheless).

It was easy, and painless, though not cheap - around $400 and 2-3 hours total for both.

[Rick Lee]

I think I'm gonna just buy one rebuilt one, eat the core charge, and buy a new outer boot for the other one. That way, I can replace the one that really needs it, repack the old one when I feel like it/get to it and then install on the other side, which is just barely starting to show signs of wear. That should save some cash. Or I can just send in the second one for the core charge a few weeks later.

[RickC]

I did whole axles, but you can repack a newer CV joint according to these threads:


rear axle shaft replacement
CV Joint - DIY or MC?

[gr8fl4porsche]

I changed the boots on my '87 - no real big deal just a little messy.
Total cost was about $ 50-60 at the local euro parts house.

My boots cracked the first time I put my car on my lift - I guess the angle with the wheels hanging down was enough to crack the worn rubber since there was no grease outside the tear.

[ChrisBennet]

Originally posted by Richard LeSchander
I think I'm gonna just buy one rebuilt one, eat the core charge, and buy a new outer boot for the other one. That way, I can replace the one that really needs it, repack the old one when I feel like it/get to it and then install on the other side, which is just barely starting to show signs of wear. That should save some cash. Or I can just send in the second one for the core charge a few weeks later.

What's a rebuilt axle go for? I haven't seen them but if they are say $100 plus core charge ($50?) why not get a new one ($200)?
-Chris

[KTL]

89911's situation is proof that you don't need to gorilla tighten these nuts. I believe most of the M10 torque specs on the motor are 42Nm = 31 lb-ft. That's not eye-bulging torque. Just nice and snug.

By Chris Martin:

Hmmm. I just had a bad outer boot on my 87. I couldnt find the outer boot for sale and read in Waynes 101 book you cannot replace just the outer boot. New axel fixed the problem, but at ~$200 I was not a happy camper.

All four boots on the CV axle are the same. I replaced all of mine two years ago. You can replace the outer boot. What you can't replace is the outer joint. It's friction welded onto the axle shaft. Boot replacement is a messy job, but at least it allows you to see what kind of condition the joint are in. Still, the time saved by just replacing the complete axle is probably worth the extra money spent. Next time I do it, I may get complete axles instead.

A complete axle from Pelican is $209. Not bad!

Axle Page

That first link that Rick C posted is a good topic. Pretty much tells you everything you need to do. Don Plumley is an excellent poster. Always gives good details about the job at hand.

[ChrisBennet]

Originally posted by KTL
89911's situation is proof that you don't need to gorilla tighten these nuts. I believe most of the M10 torque specs on the motor are 42Nm = 31 lb-ft. That's not eye-bulging torque. Just nice and snug.

Check this but I think the 8mm CV bolt torque spec was like 31ft/lbs but the later 10mm bolts are like 60ft/lbs.

I can easily hold a tire and torque the 8mm bolts but it is gut busting (for me at least) to do the same with 10mm bolts.
-Chris

[Rick Lee]

You are right Chris. There was a thread on this last winter. Someone walked me through the physics of why a 25% increase in diameter requires a 100% increase in torque.

[KTL]

Bentley should revise their spec. in the manual.

I recall it said 42/31 in there.

I do recall that I torqued mine to 60 ft-lbs. (musta got that from the tiny Porsche factory spec. book) so I should be okay. Whew.............

31 lb-ft did seem kinda low to me for the CV bolts when I read it the other day.

[Don Plumley]

As Kevin kindly mentioned, I've done the CV repack and it's not that difficult. Biggest challenge is finding the 3/4" drive tool. Since you are selling the car, instead of a $200 axle consider $40 of boots plus a little time (That's $20 x 2 for the kits that include two clamps, grease, boot and cover plate). We are beating an old horse here, but unless the CV's are worn, there is seemingly no reason the replace the joints/axles. You can almost double the life of the unit by swapping sides. It makes no sense, however, to replace a joint. Then you might as well buy a new axle for both cost and convenience reasons.

To tighten (and re-torque, you must do that!) the CV bolts, I used autobonrun's suggestion use a highlighter to mark the bolt I torqued. Then to make it easier on my aging back, with the car in the air and on stands, my son sat in the driver's seat and pressed the brake pedal to hold the axle steady. The I could rotate the axle whilst under the car to get to the next bolt.

If you didn't spin out grease, it's a good assumption that the joint is not contaminated and the CV's are in good shape. So a quick replacement of boots and grease, without the thorough cleaning mess, is a simple task. IMHO.

Let me know if you have any specific questions on the CV/Axle job.

Don

[Rick Lee]

Thanks Don. My boot is pretty shredded and I don't want to hand the car off to anyone if it's not in perfect mech. condition. I'll replace the one axle, repack the bad one and swap it out with the passenger side if I can get to it, though it's fine for now.