CV boots vs. axle

jbserra · 05-08-2007, 06:55 AM

Hello all,

Thank you for having a great, informative forum!

I have two split outer CV boots. My meticulously clean 20 year old car has grease sprayed all over the suspension pieces. Sad, sad day... I don't know how long they have been split. I was planning to replace and repack the boots. Am I just kidding myself that the joints are fine? I will obviously inspect them (I can't get to it for a couple days), but if you were to put money on it, would you guess they are shot and I should just order up some axle sets so I don't waste any time? What has been the experience with broken boots? I heard little BB things in the boot are really bad, but what if it's not that obvious? Replace them anyway? I have only had the car for 6 years, so I don't know if they've ever been replaced, and I'm at 96k mi. and 20 years.

Thanks!

IROC · IROC's Garage

When I swapped the 3.2 into my car years ago, I found that my two inner boots were split. It was obvious they had long since slung all of their grease out, so I have no idea how long they had been split (probably a long time).

I removed the CVs and disassembled them only to find that they were perfectly fine. Normal signs of wear, etc., but they were fine. I cleaned and repacked them and installed new boots and they have been fine for years.

I just recently replaced one of my outer boots (the night before a track event - doesn't it always work that way) and the CV joint itself was fine. And it's got over 150k miles on it...

Bottom line, inspect them and if they are OK, just repack and reinstall.

glenncof · 05-08-2007, 07:40 AM

jb,

Constant Velocity Joints – 1985 Porsche 911

See my posting above. It sounds like you have a 1997 and unless turbo/look-alike, the outer CV connects via wheel nut.

My first CV lasted a long time so hopefully you can do a boot replacement.

I think you could pull inner CV to replace boot but full clean/repack would require wheel nut removal. There may even be split boots for this, not requiring any CV removal.

KCinBR · KCinBR's Garage

Just replace the boots unless the cv joints are making noise.
It's not a hard job but very messy, should be able to do it for less than $50.

Cleaning and re-greasing is part of replacing the boots, that's what makes it messy

randywebb · 05-08-2007, 12:00 PM

sounds like the grease is 6 years old (?)

if so, I'd go ahead and replace all the grease.

barney911rs · barney911rs's Garage

A couple of tricks I learned years ago with CV boots.

Cut off the nozzle thing that comes with many aerosol cans in half, and put one under the edge of the boot where it seals to the axle. What this does is allow the air to move in and out as it heats up and cools down. The volume inside the boot also changes as it moves around in it's normal range of motion. Wiggle the CV around after you are done and you will hear the air moving.

Put a zip tie around the middle of the boot itself. Just tight enough to hold it snug. You don't want it to squeeze the boot. As the boot gets hot and the rubber gets softer, it keeps it from expanding from centrifugal force.

Combined these two things take some stress off the boot during it's life time. I've never had a boot rip, split, or fail in any way.

h20cooled7 · 05-08-2007, 05:01 PM

do the cv boot kits, very easy if you have air tools. i ran my car for a month without doing them and the joints were fine

aigel · aigel's Garage

If you find any grit in the remaining grease and joint, I recommend replacing the joint. It's your time and fingernails, but I'd likely go with new axles and be done. You should inspect boots frequently enough to catch them before they split.

George

jbserra · 05-29-2007, 06:03 AM

true, true...

I heard something about finding bb size ball bearings in the boots. I can't see any IN the joint, but I've found a couple (three) near the car and I'm not sure where they're from. Are there smaller ball bearings within the joint that can spring free? I have the axles out, but haven't had a chance to fully degrease and inspect. I also realized that I should be replacing BOTH boots while I have the axles out...

glenncof · 05-29-2007, 06:46 AM

Only ball bearings are 3/4" diameter, no bb's. See tear down posts in the url's on my above post for pictures.

I found the original rubber Porsche items on my '85 to be really good. In fact I have had replacement items fail in a short time (2 years while the originals lasted over 20). Perhaps an isolated incident.

I would only replace what is obviously deteriorated (unless racing).

aigel · aigel's Garage

There are no BB size ball bearings in your axles. Not sure if there are anywhere on a 911. They are more likely from the neighbor's kid's BB gun.

George

jbserra · 05-29-2007, 07:22 AM

I thought I had read somewhere, either on the forum/tech articles here, or in Wayne's 101 Project book, that he had a boot full of little ball bearings. I didn't know if they were from a bearing somewhere, or if they were little metal shavings from a self-destructing joint...

jbserra · 06-06-2007, 06:25 AM

Hello all. Thank you for the information.

I'm having a hard time determining if the drive shaft separates from the stub axle. It looks like there is just the metal lip pressed onto the stub axle to keep it from falling apart, but it doesn't readily come off. Is this supposed to separate so I can disassemble the outer joint? I can't find a replacement part for it, so I don't want to mangle it trying to remove it.

I have cleaned it with everything together, but I don't feel I got everything until I can take it apart.

Thanks.

h20cooled7 · 06-06-2007, 06:46 AM

if your loaded just replace them ,hell if your really loaded have some1 do em for you. i wish i could afford to do that.

jbserra · 06-06-2007, 07:08 AM

Well, let's see. I have probably 12 hours invested in jacking up car, lowering transmission, fighting the starter bolts, and removing axles myself. I would lean toward NOT LOADED!!!

You have a few too many cars (if there is such a thing). Maybe you can just mail me the rebuilt axles?

88-diamondblue · 06-06-2007, 07:34 AM

These may help with a few questions.
Carrera CV boot replacement

Outer joint

glenncof · 07:50 AM

You said," the drive shaft separates from the stub axle" ? I think I understand your question. You are trying to do this in place without removing stub. Yours must be late '85 onward, '87?

In this case the outer CV joint is integral in half shaft with the "stub axle". I don't have this so I can't verify.

From what I recall; I rotated the inner race of CV relative to outer race of CV. This was to align a ball bearing with open slot. Then tilted inner race to expose ball for removal. This needs to be done 5 (?) times to get all the balls.

You should go to the url's in my post. There are excellent pictures of the joints.

Repacking this should be interesting.

I would be inclined to relube inplace rather than to dismantle. My first CV went out at about 175K, never serviced.

rick-l · 06-06-2007, 08:08 AM

Quote:

Originally posted by jbserra
Hello all. Thank you for the information.

I'm having a hard time determining if the drive shaft separates from the stub axle. It looks like there is just the metal lip pressed onto the stub axle to keep it from falling apart, but it doesn't readily come off. Is this supposed to separate so I can disassemble the outer joint? I can't find a replacement part for it, so I don't want to mangle it trying to remove it.

I have cleaned it with everything together, but I don't feel I got everything until I can take it apart.

Thanks.

Sounds like yours is like my 88. The outer ones don't come apart. Fill it full of kerosene, let it sit and then do the washing machine/agitator action running the axle in and out. Follow with some brake cleaner.

jbserra · 06-06-2007, 08:39 AM

This is the '87 for those that were guessing. Sorry, I thought I had included that in my original post.

Based on the cut tin in the photos from 88-diamondblue's link in his post, I would say it's not going to come apart, AND I shouldn't because I won't be able to replace the tin.

I did a bit of the washing machine/agitator with soap and water. I will try the kerosene to see if I can get any more out.

Again, thanks for the great info. I have a Bentley manual on order now due to frustrations with a Haynes manual. It's ridiculous on how that book is put together. Hopefully the Bentley will help answer some future problems. It better not say to remove the starter, remove the allen head nuts and remove like the Haynes did...

jbserra · 06-21-2007, 12:24 PM

Thanks all for the information. The joints are reassembled. I was glad I saw the information on making sure the inner most piece had it's small sections aligned with the outer most piece's large section. I didn't think I did it wrong, but sure enough, one was wrong.

I'm not sure I did the best job, but I'm hoping it's better off then it was when the boot was broken. Time will tell. It definitely was time consuming...

Thanks again!

Oh, and the Bentley manual? WOW! I love it. The layout is the best I have ever seen. I highly recommend it. I wish I had it when I started this process!