Planet-9 Porsche Forum banner

1 - 20 of 22 Posts

·
Registered
Joined
·
15 Posts
Discussion Starter #1
Hi,

I have a question relating to the outer CV joint boot on a 987. The CV cover is a flexible rubber bellows which are attached (glued, I presume) to a thin metal flange that is then attached to the outer part of the CV joint itself. The CV joint is integral to the stub axle.

On my 987.1 2.7 Cayman the join between the metal flange and the outer part of the Cv is coming apart slightly and the grease is starting to leak. I'm keen not to drive it too much like this as I don't want to cause premature wear on the joint, but something needs to be done about it. Is it possible to re-attach the thin flange to the CV joint? I assume it is, with the right adhesive. What adhesive would anyone recommend?

To do this job in situ would be tricky in the extreme. How hard is it to remove the driveshaft from the car? Given that the CV is integral to the stub axle then I presume I'll need to undo the hub nut and withdraw the axle lengthways from the centre of rear hub. In order to get it out I will need to remove the six bolts holding the inner CV in place and detach this. How much of an ordeal is this? I've noticed that things are somewhat tight in there when it comes to clearance. Can the driveshaft be jiggled out once the bolts are removed or will I need to dismantle the rear suspension on that side to get it all apart?

All pointers, advice and guidance welcome! Thanks.
 

·
Registered
Joined
·
217 Posts
I had to remove one of mine (987.2) and it was easier since it was during a suspension refresh so the dampers were out of the way.

You can remove it with suspension in place. After removing the axle nut and the bolts attaching it to the gearbox, you'll likely need to remove part of the exhaust to lower the axle out of the way.
 

·
Registered
Joined
·
32 Posts
Hi, I've just replaced all four of my CV boots over the Christmas holiday whilst replacing every suspension component on my 2007 2.7 987.1 Cayman. I removed my driveshafts to do this as I wanted to strip the inner CV joints, clean them and re-grease. You're right to be cautious about using the car if the boot is split and grease is leaking out as grit and road crap will soon get in the joint and ruin it. My boots all had the original Porsche compression type clamps sealing the ends of the boots to the flanges and these were easily removed with wire cutters/pliers. New clamps can be bought at most motor factors. The drive shaft end of the boot is about 39mm in diameter and the flange end is about 67mm, but mine were very generously oversized so cut them down before fitting, they're open ended so can be fitted on the car but squeezing up the hub end might be a bit of a tight squeeze, so if you do it yourself and you get the special pliers get an 45degree offset pair. If your an experienced home mechanic Its probably worth removing the shafts and replacing all 4 boots, there are plenty of vids on youtube of how to do it (and some of how not🤣)
 

·
Registered
Joined
·
15 Posts
Discussion Starter #5
Cayman68,

Thanks. What else did you have to remove to get the driveshafts out? I've rebuilt driveshafts before on other cars and that bit of the job doesn't worry me but I've never liked working on exhaust systems!

How were the thin metal flanges holding onto the outer CV's on your car? One of mine is starting to come adrift, hence this thread.
 

·
Registered
Joined
·
37 Posts
Just replaced both boots on my 06 Cayman S. All you have to remove is the aluminum bracing. No need to remove anything else there is plenty of room to slide the axle out of the hub.

On second thought you may not even need to remove the aluminum support/underpanel. I did because I also changed the transaxle fluid while I was in there.

Sent from my SM-G930V using Tapatalk
 

·
Registered
Joined
·
37 Posts
Cayman68,

Thanks. What else did you have to remove to get the driveshafts out? I've rebuilt driveshafts before on other cars and that bit of the job doesn't worry me but I've never liked working on exhaust systems!

How were the thin metal flanges holding onto the outer CV's on your car? One of mine is starting to come adrift, hence this thread.
The 6 bolts connected to the transaxle are an 8mm hex and the axle nut is a 32mm

Just lightly tap the metal flange out carefully with a hammer and flat head. When you reassemble, take a piece of wood and lightly tap it back on with a hammer. Very easy to do.

You will need the special tool to remove the circlip that holds the outer joint to the axle. Once that is off you can easily replace both boots. I soaked the CV joints in mineral spirits over night and blasted out any remaining grease with brake cleaner and compressed air.
Sent from my SM-G930V using Tapatalk
 

·
Registered
Joined
·
32 Posts
When you say the thin flange is starting to come adrift, do you mean its badly corroded? The CV joint housing on my car had surface rust, but the flange where the boot is clamped was like new and it all looked sound. I'm sure I have seen a video on Youtube of the drive shaft taken out without removing any of the exhaust, but that might be the least of your problems;
The 32mm hub nut is torqued to 340 LBS/FT and if its been on there all the cars life then it might be hard to loosen.
I bought a cheap 450Nm electric impact ratchet from Machine Mart that made short work of it, but the real problem was getting the drive shaft out of the hub. My hub was off the car (see pic) as I had removed all the suspension parts, removing the 6 inner bolts from the gear box end was easy but you'll need a 12mm Triple Square bit (if its the same as mine, but it seems some are Allen heads) and a very long extension bar or 2 extension bars and a breaker bar or long ratchet. Just put the car in gear and loosen the 2 most accessible bolts, then put the car in neutral, rotate the hub, put the car back in gear and loosen 2 more, repeat. When I had the hub on the old piece of carpet I put under the car when I'm working on it I used an aluminium drift and lump hammer to whack it out of the hub, it was extremely tight and wouldn't budge so I stood it on end and put plenty of WD40 to soak over night. Even then it wouldn't move so I very carefully warmed the hub (the wheel bearing and ABS/PSM sensor are in there!) Then eventually it broke loose and reluctantly came out. The other side came out slightly easier. Breaking down the ball joint on the coffin arm was difficult too, a large, good quality joint splitter is essential as was some means of warming the hub, and its very easy to damage the rubber boot. But by far the hardest to remove was the bolt on the top end of the drop link, through the wheel carrier, clamping the strut in place. I didn't even attempt this as I had been warned the bolts seize in and can be impossible to remove, so 6 months ago I put it into Porsche Cheshire Oaks to replace all 4 drop links and both
anti- roll bars and bushes. It took them 4 days to get them all out without replacing/damaging anything else, I wasn't really complaining as I had agreed the price in advance and I had a brand new 718 Boxster as a curtesy car.
If you've got plenty of time to work on your car its worth doing yourself if you are capable but if its your everyday driver
like mine then factor in plenty of time for seized parts which may have to replaced.
266378
266379
 

·
Registered
Joined
·
15 Posts
Discussion Starter #9
Guys,

Thanks for these replies - they are very helpful. It sounds like I won't have to dismantle the suspension to get the driveshaft out, which is good news.

Bougie, what is the special tool to remove the outer CV from the driveshaft? (I thought they didn't come apart which is why you can only buy the whole thing as a single assembly?)

Cayman'68, thanks for that detailed write-up. I am however a little confused; you describe the travails of dismantling the rear suspension after having said that it should be possible to remove the driveshaft with minimal dismantlement. Was that just to pre-warn me of the pain I have in store when I do tackle the suspension refresh job? :)

I don't think that the tin plate that is coming away from the CV is rusty, it's just that it is coming away. How would it have originally been attached - welded on? My plans currently are to take the driveshaft off the car, clean out both CV joints and re-lubricate them and see what can be done about the tin plate, as that is the presenting problem and the reason for taking it apart. The force on it will be small so I am hoping that a good clean and then some glue of some kind should hold it together. I'll clamp it while it sets and keep my fingers crossed. Then put it all back together.

I am currently wondering whether to tackle the job tomorrow or not. I don't have a garage so will be working outside by a (quiet residential) road. The question will be daylight and when I next need to drive the car. If all goes well it doesn't look too tricky, but cautionary tales such that Cayman'68's one about the hub being tricky to remove make me cautious!

(Nice car BTW Cayman'68 - identical to mine! Thanks for the photo).
20190725_143528.jpg
266381
 

·
Registered
Joined
·
32 Posts
Yea, sorry I’ve just realised how much I rambled....I usually do that when I’m talking about Porsche. I just wanted to let you know of some of the problems that you might encounter if you can’t get the drive shaft out without stripping the suspension. I don’t think I would have got the splined end of the drive shaft out of the hub with it in situ.
Bougies description of removing a flange with a flat head (screwdriver?) and tapping it back on with a piece of wood sounds more like the inboard end CV joint to me, and the only special tool required to get the CV joint off the splines is a pair of circlip pliars. I didn’t see any way of dismantling the outer end of the CV joint/stub axel, like you say, I don’t think it’s meant to dismantle, but I could be wrong. Let us know how you get on I’m genuinely interested, post a couple of pics if you can of the flange part that is coming apart. Good luck.
 

·
Registered
Joined
·
37 Posts
Guys,

Thanks for these replies - they are very helpful. It sounds like I won't have to dismantle the suspension to get the driveshaft out, which is good news.

Bougie, what is the special tool to remove the outer CV from the driveshaft? (I thought they didn't come apart which is why you can only buy the whole thing as a single assembly?)

Cayman'68, thanks for that detailed write-up. I am however a little confused; you describe the travails of dismantling the rear suspension after having said that it should be possible to remove the driveshaft with minimal dismantlement. Was that just to pre-warn me of the pain I have in store when I do tackle the suspension refresh job? :)

I don't think that the tin plate that is coming away from the CV is rusty, it's just that it is coming away. How would it have originally been attached - welded on? My plans currently are to take the driveshaft off the car, clean out both CV joints and re-lubricate them and see what can be done about the tin plate, as that is the presenting problem and the reason for taking it apart. The force on it will be small so I am hoping that a good clean and then some glue of some kind should hold it together. I'll clamp it while it sets and keep my fingers crossed. Then put it all back together.

I am currently wondering whether to tackle the job tomorrow or not. I don't have a garage so will be working outside by a (quiet residential) road. The question will be daylight and when I next need to drive the car. If all goes well it doesn't look too tricky, but cautionary tales such that Cayman'68's one about the hub being tricky to remove make me cautious!

(Nice car BTW Cayman'68 - identical to mine! Thanks for the photo).
View attachment 266381 View attachment 266381
Something like this.

The inner CV joint is removable, not the outer. There are a few youtube videos showing how to separate the CV joint from the axle. Very straight forward just a messy job. My advice is to buy extra boot clamps in case you screw up.

With the inner CV joint off you can now replace the outer boot as well. This can be done without removing the axle but you will have limited working room up.


Sent from my SM-G930V using Tapatalk
 

·
Registered
Joined
·
217 Posts
Kiznarsh,

Thanks. Which bit of exhaust will need to come off? How hard is it to remove?
Since I removed the axle while it was still in the wheel carrier, I didn't need to remove part of the exhaust but while I was under the car, I was picturing not being able to remove the axle & carrier together, but maybe I'm misremembering.

I have a pretty thorough account with plenty of pictures in my thread. Feel free to start reading at the post below as it should help explain things:

 

·
Registered
Joined
·
15 Posts
Discussion Starter #13
Guys,

Thanks for the replies. All very helpful. I'm used to working with CV's and have rebuilt many, both on VW's and my earlier 944. However I've never come across a driveshaft where the CV can't be removed from it .... every day is a school day!



I'm currently psyching myself up to do the job. I have a 32mm socket, a long breaker bar (will it be long enough?), a bit tub of CV grease, the various triple square tools to get the six inner bolts off, a hammer and drift to remove the stub axle from the hub .... all I need to do now is get on with it!

Bougie / Cayman68 - thanks, I have a set of those circlip pliers from doing the same job previously on other cars.

Kiznarsh, thanks for the link to the pictures and description. I've read it carefully. I've made the same mistake assembling a CV such that it locks at 90degrees! I think I'll wade on in and see how I get on and remove more stuff as necessary.

Kiznarsh and Cayman68 have both commented on how hard it can be to get the suspension apart. One of the jobs for the summer is a bit of a suspension refresh so I consider myself forewarned!

Thanks again for your help. I'll update this thread when I have something to tell.
 

·
Registered
Joined
·
15 Posts
Discussion Starter #14 (Edited)
Update! (But not the one I was expecting to post ... )

I started getting everything out to do the job as planned, and realised that the large socket that I thought was 32mm was actually 30mm (the right size for the hub nut on a 944 and a VW Golf.) Having checked the car the required size is indeed 32mm (precisely as Bougie said) so I have ordered the right size tool and will do the job when it arrives.

While I didn't do the job I did jack the car up and had a good look at things. I can see that getting the driveshaft out without removing anything else would be a prize wiggle but may be possible, but it'll be much easier to take the bottom plate and the bracing bars out.

I've attached some pictures of the outer CV to this eMail. It's not pretty. The boot is fine but the grease is leaking out from somewhere (and it's not immediately apparent where) and building up on the surrounding hardware - the photos were taken after I had poked it all around with a screwdriver. The green stuff is grease and you can see the CV boot on the right, the clip holding it on to the circular metal plate and the edge of the plate where it is wrapped over the outer part of the CV joint. The grease is coming out of somewhere but the pile of it (and corresponding smear) doesn't seem to be lined up with the edge of the circular plate - which you would expect it to be if this was where it was spilling from. However unless there is something else in the vicinity that can produce grease like this then I can't see where else it could be coming from.

What I can't explain is the ring of debris poking out from behind the plate where it sits over the CV. This seems to be very rusty thin metal. You can see this in the photo sitting next to the ring of grease, casting a shadow to the left.

The car is not producing any symptoms of problems; the CV's run smoothly and quietly. However I still think I'd like to get them apart to have a good look inside and and cleaned out. I'll slide the CV boot along the driveshaft and clean all the rust off the circular plate and the outside of the CV joint itself. I'll clean the old grease out of the joint and pout some new stuff, and see what I can use to re-seal everything before putting it back together.

If anyone has any thoughts then let me know, otherwise I'll update this thread when I have done the job.

Thanks for your help thus far.

IMG_20200111_113917.jpg
266388
 

·
Registered
Joined
·
37 Posts
Update! (But not the one I was expecting to post ... )

I started getting everything out to do the job as planned, and realised that the large socket that I thought was 32mm was actually 30mm (the right size for the hub nut on a 944 and a VW Golf.) Having checked the car the required size is indeed 32mm (precisely as Bougie said) so I have ordered the right size tool and will do the job when it arrives.

While I didn't do the job I did jack the car up and had a good look at things. I can see that getting the driveshaft out without removing anything else would be a prize wiggle but may be possible, but it'll be much easier to take the bottom plate and the bracing bars out.

I've attached some pictures of the outer CV to this eMail. It's not pretty. The boot is fine but the grease is leaking out from somewhere (and it's not immediately apparent where) and building up on the surrounding hardware - the photos were taken after I had poked it all around with a screwdriver. The green stuff is grease and you can see the CV boot on the right, the clip holding it on to the circular metal plate and the edge of the plate where it is wrapped over the outer part of the CV joint. The grease is coming out of somewhere but the pile of it (and corresponding smear) doesn't seem to be lined up with the edge of the circular plate - which you would expect it to be if this was where it was spilling from. However unless there is something else in the vicinity that can produce grease like this then I can't see where else it could be coming from.

What I can't explain is the ring of debris poking out from behind the plate where it sits over the CV. This seems to be very rusty thin metal. You can see this in the photo sitting next to the ring of grease, casting a shadow to the left.

The car is not producing any symptoms of problems; the CV's run smoothly and quietly. However I still think I'd like to get them apart to have a good look inside and and cleaned out. I'll slide the CV boot along the driveshaft and clean all the rust off the circular plate and the outside of the CV joint itself. I'll clean the old grease out of the joint and pout some new stuff, and see what I can use to re-seal everything before putting it back together.

If anyone has any thoughts then let me know, otherwise I'll update this thread when I have done the job.

Thanks for your help thus far.

View attachment 266387 View attachment 266388
Sounds like a plan. Once you remove the inner CV joint from the transaxle you will notice how much room is freed up to remove the axle from the hub if you want. I loosely kept the axle nut on and tapped it with a hammer to slide the axle out. Car has 150k miles and no rust so it happily obliged. Getting it back in is just a little more tricky but there is more that enough wiggle room. I would recommend getting new axle nuts as well. They are meant to be torqued once.

Sent from my SM-G930V using Tapatalk
 

·
Registered
Joined
·
15 Posts
Discussion Starter #16
Bougue,

Thanks. I've just ordered the tools on-line that I will need to do the work, and four replacement CV boot kits as well. Having them in hand should I tear one can only be a good thing.

Thinking about it, are the driveshafts the same on both sides? (987.1 2.7.) If they are then there is a potential gain in swapping them over as they then run on the 'back' side of the CV joints and will have an extended life.
 

·
Registered
Joined
·
15 Posts
Discussion Starter #17
OK, too much time spent on the computer and I've found this video.


It shows the axle removed from the car and the guy has a good look at the design of the outer CV. It shows that the circular metal plate is pretty snugly attached to the CV joint itself, which leads me to wonder whether the grease that has appeared on my car is indeed coming from there.

I guess I come back to the point I made a couple of posts back: if it hasn't come from there then where can it have come from? There isn't anywhere else locally which has that much grease of that type (assuming that the green grease started out as grey CV joint grease) so it must have come from there.

All observations welcome. Although I can't see any alternative to removing the axle and taking it apart and eyeballing it.
 

·
Registered
Joined
·
877 Posts
Thinking about it, are the driveshafts the same on both sides? (987.1 2.7.) If they are then there is a potential gain in swapping them over as they then run on the 'back' side of the CV joints and will have an extended life.
The drive shafts are not the same on both sides.
 

·
Registered
Joined
·
217 Posts
The video is correct...the outer CV joints are not serviceable.

If the outer boot isn't ripped, only other possibility would be your wheel bearing.

If your outer boot is ripped, then you'll have to get a new axle. I believe aftermarket ones are available.

Basically as I'm sure you've realized by now, you'll have to take it apart to really understand what's going on. Keep us posted!
 

·
Registered
Joined
·
32 Posts
zcacogp, when I removed the rubber boots and cleaned my outer CV joints (as best I could) the grease inside was exactly the same shade of green as the grease in the two photos you've posted. I was surprised as I expected it to be graphite grey. It had been in the CV joints for 13 years and I'am guessing that its discoloured and degraded over time. Where the grease appears to be leaking in your photos of your stub axle seems to be around where the guy in the video you posted mentions an interface of plastic/metal of the CV joint housing. If this is the case you might be as well replacing the drive shaft first as last, that's what I'd be doing if this where my car.
 
1 - 20 of 22 Posts
Top