[urq] NAC : CV joint rebuilt... SOLVED !

[laraa at sympatico.ca]

Hi again folks,

Looks Ol' Louis-Alain did indeed something wrong. I didn't clock the 3 parts together correctly the first time. You need to match the small portion of one race to the big portion of the other. Look at this Ferrari owner page, there is a nice photo with yellow arrows to show what to do (that I didn't...).
http://www.birdman308.com/service/cv_joints/cv_joint.htm 

Now, it is not completely my fault. When I compare the NTN catalogue technical drawing and the corresponding photo, they don't match to the white paint marks on my joint. I'm guessing there was a mistake during assembly, or they didn't care since this joint won't ever see the full angle it was designed for. The cage could touch the shaft if the joint reach its full 10 degrees. But it won't ever go further than 2 or 3 degrees in this configuration.

Anyway, the positive side is I now know how to rebuilt a CV joint (and you do too)... I'm very good at removing this car driveshaft : how about 15 minutes once the car is on the ramps ? I also have a very nice metal picture of the underside of the car.

So, to paraphrase my new idol (Edd China from Wheeler Dealers) : Result !

Louis-Alain


-----Message d'origine-----
De : quattro [mailto:quattro-bounces at audifans.com] De la part de laraa at sympatico.ca
Envoyé : 25 mai 2015 12:16
À : audi at humanspeakers.com; quattro at audifans.com; urq at audifans.com
Objet : RE: [urq] NAC : CV joint rebuilt...

This is a 3 part propshaft : 2 center bearings, 2 u-joints, 2 CV joints. I also found a Swedish university paper about the development of this driveshaft. The student was trying to understand how to minimize vibrations, and the conclusion was : don't install it in a straight line, each joint must be in a angled position. So, from what I see down there, the propshaft goes upwards and a bit to the side from the transmission to the rear diff. See this forum for a picture : http://saabworld.net/f98/2008-saab-9-3-turbo-x-united-kingdom-press-release-328/ 

To answer your question, Huw, : yes I did replace the 2 center joints at exactly the same spot. Paint was used to mark the position. And these 2 supports are not adjustable, except for a millimeter or 2 from side to side.

Louis-Alain

-----Message d'origine-----
De : quattro [mailto:quattro-bounces at audifans.com] De la part de Huw Powell Envoyé : 25 mai 2015 00:27 À : quattro at audifans.com Objet : Re: [urq] NAC : CV joint rebuilt...

I've been sort of following this, on and off.

What about the center bearing?  Did that end up in exactly the same place as before?

- Huw

On 5/24/2015 11:52 PM, laraa at sympatico.ca wrote:
> Thanks Frank,
>
> It was my first CV dismantling, hence the reason I didn't pay attention to how it was assembled. Second, I was not expecting any marks on the parts, I discovered them after cleaning. That grease is very nasty...
> Third, when reassembling the joint, I decided to align all the paint marks on the same side and the 3 marks following a radial line.
>
> Finally, I tried to push the inner race on the splines with the white marks toward the end cap, but it stopped before I could put back the circlip (snap ring) in its groove. So I turned it back and then, it slipped all the way in. Then, the outer race was placed with the dots on the same side, which put the external machined groove on the correct side for the end cap. The ball cage paint mark is also on the same side. But in this configuration, which is the most logical, vibrations occurred.
>
> But to answer your question, yes the joint was sliding and pivoting easily. Not as smooth as a well worn CV halfshaft, but smooth enough to my taste. That joint doesn't see much angle, maybe 1 or 2 degrees, and the relative play of the diff and shaft is minimal.
>
> So back under the car, I will have to show that joint to a good shop. I will also take the time to drive the car without the propshaft, if I can find a suitable plug for the transmission output shaft. The other solution is to put the car on 4 jackstands, and place a dial gauge to see where is the runout.
>
> More to come !
>
> Louis-Alain
>
> -----Message d'origine-----
> De : urq [mailto:urq-bounces at audifans.com] De la part de Frank de Kat 
> Envoyé : 23 mai 2015 17:40 À : urq at audifans.com Objet : [urq] NAC : CV 
> joint rebuilt...
>
> Hello Louis-Alain:
>
> A quick question:
>
> When the unit was 'reassembled', did it still 'flex' properly?
>
> I ask, as after a *very* late night  Audi adventure, I managed to 
> reassemble an Audi UJ wrong, and didn't notice until I got it back on 
> the car. I had managed to get the center section 'flipped over' on the splined shaft.
> (And as Scott says, it either goes back right, or it doesn't!)
>
> You can't really go wrong 'indexing' the parts, as I can't see how changing their position relative to each (angularly) other could matter very much. They are high  precision bits.
>
> Not totally clear from your description,  but  If you did  get the middle part that goes on the splined shaft 'flipped over' when reassembling (and it Can be done!), the joint doesn't work properly, and flexes lite (if at all), giving no "CV joint" action.
>
> (In other words, if you had the center part that goes on the spline, 
> reversed to how it came apart, relative to the part with the 6 bolts)
>
> You couldn't get away with that on a drive axel, but if it were on a very straight driveshaft, it may have gone back wrong without being noticed,  and the  not getting any "CV" action could cause vibration..
>
> (Having been burnt once,  now when I re-grease CV joints, I *always* 
> pay attention to how the center section is oriented when taking apart, 
> and always test after reassembly..)
>
> Regards,
>
> =Frank de Kat=
>
>
> Quoting urq-request at audifans.com:
>>
>> Message: 1
>> Date: Fri, 22 May 2015 17:49:32 -0400
>> From: <laraa at sympatico.ca>
>> To: <urq at audifans.com>,	<quattro at audifans.com>
>> Subject: [urq] NAC : CV joint rebuilt...
>> Message-ID: <BLU436-SMTP769A2066FAAA429DB84BF9CEC00 at phx.gbl>
>> Content-Type: text/plain; charset="us-ascii"
>>
>> Hi everyone,
>>
>>
>>
>> Ex-urq owner still needing your fountain of knowledge about a 6-ball 
>> cv joint on a Saab propeller shaft.
>>
>>
>>
>> In short, I had to remove the propshaft from the car to get access 
>> for another job. The "while in there" jobs included repacking the 
>> rear CV joint with fresh grease. Just to be sure everything was 
>> clean, I removed the joint from the shaft, without taking pictures beforehand. Silly me.
>>
>>
>>
>> After inspection, when the parts were clean, I found 3 little white 
>> paint dots on each part (inner race, cage, outer race). I thought 
>> these were necessary to align everything when rebuilding. That's what 
>> I did. I also realigned the completed CV joint with the splined 
>> shaft, because I took care of marking the CV boot and the outer race before dismantling.
>>
>>
>>
>> And now, the driveshaft vibrates at 15 mph and again at 50 mph. I 
>> must have done something wrong.
>>
>>
>>
>> Does anyone here have a few tips about rebuilding these ?
>>
>> Where do the paint marks goes ? Inside (cv boot) or outside (end cap) ?
>>
>> Do they go all on the same side of the assembled joint ? (I think.)
>>
>>
>>
>> I am puzzled because I found the PDF catalogue for that NTN LJ 75 
>> joint here (that's Lincoln Jaguar 75) at page 19:
>> http://www.diago.sk/diagowebsite/files/cvj-forautomobile_en.pdf
>>
>>
>>
>> On the drawing, I can see the cage has a bevel which goes inside.
>>
>> The inner cage has a lip which goes outside toward the circlip.
>>
>> The outer cage has a machined surface that goes outside as a recess 
>> to accept the end cap. (as on the photo lower on the page)
>>
>>
>>
>> If I do all that, then the 3 paint dots are not on the same side of 
>> the joint, hence my confusion.
>>
>>
>>
>> It's not an Audi, it's a Saab, but at least the 6 bolts that hold 
>> that rear CV joint to the diff are from Audi, since Saab is MIA here 
>> in Montreal. I did my usual auto-archeologist stuff to bypass a problem with parts supply.
>> I remembered that the urQ had similar bolts, so a quick stop at an 
>> Audi dealer provided me the almost correct (3 mm longer) bolts for the Saab.
>>
>>
>>
>> So, anyone has a clue ?
>>
>>
>>
>> Thanks in advance !
>>
>>
>>
>> Louis-Alain
> _______________________________________________