cv joint reinstall

[juanbenae]

i am aware that the cv joint goes in one way and one way only and reassembly incorrect can cause it to destroy itself upon rotation. i swapped out a torn inboard boot today and got it all back together and it seems to spin well. i put a bottle jack under the rear control arm and moved it along its radious by jacking it up from the relaxed state with the car on stands. this simulated the compression of the suspension, and even in a compressed state i experienced no type of binding in the cv as i rotated the axel. i have not run it with the wheel and weight on the rear as it was dark and raining.

would have i experienced any type of binding during my axel radious experiment had i reassembled the joint 180* off, and it was wrong? i will roll it out in the morning and see that it does not bind with the wheel and weight on it. i have got to degrease the tranny and rear wheel well area from the torn boot anyway.

should i continue to pucker my ass until it rolls and i can put power to the wheels w/o hearing bad things? or would i have noticed it being bad by spinning th axel after reassembly?

anyone?

[CarreraS2]

From what I remember from doing this a few years ago, you'd know if it was assembled wrong. I had it wrong at first and the range of movement was much much less (very noticeably so) than it should have been. It easily went together wrong, but once assembled it was clear it was wrong.

At least that's what I remember.

[randywebb]

I don't really understand your description. Are you saying that you may have rotated the unit 180o so that the outer CV joint may now be where the inner one was?

Also, I am not certain that the consequences are so dire if the CV's are run in reverse. Where did you hear that they would destroy themselves? I suspect that if the unit is rotated 180o as above that you would hear a noisy clicking or brrrrrrr noise that was not present before. You could then reverse the unit. But... I don't know for sure. Maybe someone like John Walker will post on this.

You might be able to match the indentation pattern on the gaskets, or scratches on the CV's and their mounts to get it mated back up.

If not, then it may be time to kick back with a beer and let some others post -- or to sleep on it for the same reason. Did you already do a search as to how much damage can be done if they are swapped end to end when reinstalled?

[CarreraS2]

Yeah, I guess I'm not really sure what you're talking about, either.

I assumed you meant reassembling the cages and balls incorrectly. That's what I did. While it went together ok, it was obvious it was wrong because there was no range of movement. Took apart and redid correctly and it was fine.

If you're talking about some other issue . . . dunno.

[smestas]

The outsides of the CV's have a notch to one side. This side needs to be towards the flanges and not the boots. At least that’s how I read to do mine.

[smestas]

Heres a pic to help.

[juanbenae]

yeah simon you are on the right track there. i got it back in with the groove facing the tranny, as i was able to determine that by looking at the other unmolested side prior to reassembly. it is possibly to have the innards installed 180* off and still have the groove in the correct spot. the joint is a rubics cube to get apart and put back together.

heres some more info, very obscure but if you have had one apart you may be familiar. the inner race, the one with the grooves that mate with the axel on one side has a small dimple on the face that goes toward the tranny, or hub on the outer unit. it is a factory placed mark of some sort and i think it may dictate reassembly. i put this dimple facing the tranny, on the same side as the groove mentioned at the open of this entry to the thread.

i am pretty sure brian has experienced what i am talking about by his explaination above. it was described by my wrench much like you write above regarding you will "know right away its wrong".

brian did you have to have the car with wheel on and off the jacks to recognize it was bad, or was it noticable while still in the air with the wheel off while rotating?

randy i referenced as many past threads as i could find on the subject prior to undertaking the project, so yeah i have done research here. in fact if we all put type cv joint like "cvjoint" from here on out it would help the search on the topic. the search does not recognize just the "cv", i used the words axel and had the most success.

well i would at this point suspect i have it back together correct. hopefully the rain will stop today and i can take it out. this rain the last two weeks has limited my test drives on recent work. the next run will be rear caliper rebuild (last weekend) and cvjoint boot this. i should get AAA before the next test drive,, eh?

[no substitute]

There are wide and narrow sections on the inner and outer races. As I recall you don't want wide next to wide (or narrow next to narrow). You want wide next to narrow. If you don't assemble this way, the joint will not have the considerable range of motion necessary, i.e., the joint will not tip from side to side.

[randywebb]

you want to search on axle, not axel (unless you want posts on a G&R Guitarist...)

still not clear on what might be reversed where.... post the specifics if you are still unsure or are worried about consequences of doing it wrong. Don't forget to replace the locking washers, and to retorque the bolts after a while.

I'm sure lots of people will review this thread after the weekend.

[juanbenae]

it was done correct, at least the cv reinstall. the spelling is an different story....

i would be curious to see if someone does chime in on the dimple on the face of the inner cv race is standard and to face the groved outer portion of the joint.

couple other things, mine did not have the little flange deals that tie the bolts together two at a time as shown in the bently. mine also had standard 6mm allens (no 12 sided fancy ones), w/ no washers. i put lock washers on during my reinstall as directed in past threads.

i really do need to get a digital camera, a dictionary, and a guns-n-roses cd...

brians 1st post lead me to figure i nailed it, as always thanks for the insight on things.

[makaio]

Originally posted by k911sc

couple other things, mine did not have the little flange deals that tie the bolts together two at a time as shown in the bently. mine also had standard 6mm allens (no 12 sided fancy ones), w/ no washers.

That's how mine are on the 78.

[juanbenae]

here is a pic of the cv with the dimple i speak of. again it is on the inner cage face with the spline gears. in this pic it is at about 5 o'clock. again this is to face the side of the cv outer housing with the groove in it.

hope this helps someone in the future

[Grady Clay]

Notice how the inner race of the CV has wide and narrow
spacing between the ball races.
The outer race is the same way.
When they are assembled “inner wide facing outer narrow”
and “inner narrow facing outer wide” that is correct.

It is possible to assemble them “narrow-to-narrow” and
“wide-to-wide”. That is wrong and will destroy the CV.

Every CV should be exercised through its full range on motion;
both axially and angularly after reassembly and greasing.
First to verify it is assembled correctly and second to feel
for any stiff places.

When inspecting a CV, it is best to keep it all together while cleaning.
Much inspection can be done while it is still assembled.
When disassembling a good CV it is best to maintain all
the components in their original position and orientation.
This takes some effort and little dabs of touch-up paint help.

The points of failure/ware are the balls, the inner & outer
races, and the cage.
Balls that are black or damaged, races that are noticeably grooved,
and cages that are cracked or badly worn call for replacing the CV.

Of course you would always replace the rubber boots and
the Schnorr lock washers and CV gaskets where appropriate.
Carefully inspect the CV bolts and replace them if there is
sign of damage to the hex or there is any rust.
Assemble the CVs with a light coat of oil and no grease
on the bolt threads. Yes, this is difficult to accomplish.

Many times it is desirable to just replace the entire
axle-CV assemblies with new.
Make sure you get new OEM Lobro parts.





Best,
Grady

[juanbenae]

thanks grady! i must have gotten it right, i drove the car yesterday about 15 miles with no bad noise.

[Grady Clay]

When you were doing this as a “first time” DIY, what other questions did you worry about? Wayne’s “101 Replacing CV Joints” is pretty good but you can put only so many words and pictures on two pages. That is where Wayne’s Tech articles and this Forum come in.

What more needs to be added here?

Best,
Grady

[Gunter]

I found no reason why the CV joints cannot be switched on SC's and the groove on the outer race is a mistery. I switched my CV joints to obtain a fresh surface for the balls and the groove is now on the inside. Been running for about 20k and counting. See:
CV Experts, why not flip a CV joint?

[juanbenae]

you know i did not even look in 101 projects on this one. there were a couple good threads i researched, and the bently. i should have got out the 101 too.

the pic grady posted above noting the wide/thin groove deal would have been very helpful. long and short is i got it and ready for the next boot to go south on me.

[randywebb]

Grady,

1. What if one drops the balls and they are not replaced in the same "sockets/holes"? I did this a year or two ago, and they seem to run fine now, but I've hear that wear can be accelerated.

2. What do you think of the idea that some have put forward about swapping the entire half-shaft assemblies from the LH side of the car to the RH side? I think that is what Gunter is saying just above.

3. "Assemble the CVs with a light coat of oil and no grease
on the bolt threads. Yes, this is difficult to accomplish."
- I think Jim Sims posted once that the threads should be dry.
- Also, a Q-tip and brake cleaner work to remove extraneous grease.
- For anyone wondering, the presence of grease or oil on the threads will affect the troque to tension relation for the fastener.

4. "What more needs to be added here?"
- Someone might want to look up the threads giving the VW manual pages on CV joints, and some of the other threads, and include the URLs here.
(I always figure that the person to do this is the one who is just about to do the work on their car...)

[juanbenae]

this was VERY helpful, after the fact...

http://volksweb.relitech.com/cvjoints.htm

[Grady Clay]

Randy,

1. What if one drops the balls and they are not replaced in the same "sockets/holes"? I did this a year or two ago, and they seem to run fine now, but I've hear that wear can be accelerated.

>>I think a good CV does just fine moving the parts around. The issue is if they have mating surfaces for many years – keep them that way and just inspect & lube. In Lobro’s manufacturing process, I wouldn’t be surprised if they custom fit ball size for each CV – particularly for high end use like 911.

2. What do you think of the idea that some have put forward about swapping the entire half-shaft assemblies from the LH side of the car to the RH side? I think that is what Gunter is saying just above.

>>I agree. If you are doing regular maintenance, this is a way to spread the wear. Having the drive torque in the opposite direction accomplishes that. Also the outboard CV sees the additional inertial loads from the suspension vertical acceleration.

3. "Assemble the CVs with a light coat of oil and no grease
on the bolt threads. Yes, this is difficult to accomplish."
- I think Jim Sims posted once that the threads should be dry.
- Also, a Q-tip and brake cleaner work to remove extraneous grease.
- For anyone wondering, the presence of grease or oil on the threads will affect the troque to tension relation for the fastener.

>>While I agree with the lube-torque issue, the undercarriage hardware on a street 911 is in a very harsh environment. I like a little corrosion protection.

4. "What more needs to be added here?"
- Someone might want to look up the threads giving the VW manual pages on CV joints, and some of the other threads, and include the URLs here.
(I always figure that the person to do this is the one who is just about to do the work on their car...)

>>Good idea.

Best,
Grady