DIY: Inner CV Joint, R&R with new Redline CV2 Grease

[ckpitt55]

^^ good point

[tjm3]

By the way, the inner metal cap is more of range limiter than a grease retainer and it looks more like a piece for shipping the axles. Without the cap, the axle has enough motion to allow the balls to pop out while handling. Once the axle is installed, it never sees enough angle to allow this to happen.

[ckpitt55]

By the way, the inner metal cap is more of range limiter than a grease retainer and it looks more like a piece for shipping the axles. Without the cap, the axle has enough motion to allow the balls to pop out while handling. Once the axle is installed, it never sees enough angle to allow this to happen.

agreed, but it also provides the sealing surface for the boot. not sure how well it would fit without the cap installed underneath it. I could check this, as I haven't put the outer joints back together yet. Assuming it seals up alright you technically don't need the cap if you're careful.

[tjm3]

That was just for info, I would use the cap. The only reason I mentioned this was because I bought a couple of GS-P rebuilt axle units for the M3 ($75, go figure) and one came missing the cap. The CV joint/spline was cocked at an extreme angle and seized right out of the box. I couldn't tell if the balls fell out, but it was jammed so tight that even clamped in the vise and hammering the thing it wouldn't come loose. (I OK'd this highly technical procedure with the parts guys prior). Sent it back for another.

[ckpitt55]

finally got around to putting one of the outer joints back together last night. it was tricky as hell, you need to be an octopus to do this proficiently but it can be done with some patience. notable tips and order of reassembly to save you some frustration:

-slide boot down over half shaft
-put on metal housing retainer
-reinstall the snap ring if you took it off and slide on the metal collar that inner bearing race references to.
-install inner bearing race to cage prior to pressing it onto the splined section of the shaft
-press on bearing race and install snap ring
-put a small amount of grease on everything (just enough to prevent binding, but not enough to make a mess)
-lie the outer joint housing down on its side on your bench, and align the thicker section of the inner cage to the smaller section on the housing (same as with the inner joints)
-start inserting bearings. I found it was easier with the axle hanging off the work bench to give you more room to move it around and work them in. careful though - if you rotate it too far in any direction, the bearings drop out of the bottom of the raceway inside the housing and you have to take it apart and start all over.
-repeat this until you have all the bearings in. take your time with this, frustration will result if you try to rush it. once they're in, try not to move the shaft relative to the housing until you hammer the crimp on retainer onto the outer housing.
-hammer / re-crimp the retainer, pack the joint with grease, and work it in into the joint.
-throw some more grease in there for good measure, slide the boot down over the joint and clamp it up.

an edit is reserved for later when I have the chance to post some pics, might help make things clearer.

[HighandFast]

ckpitt55: so post some pics, already

Good tips.

[ckpitt55]

Wow, forgot about this one. Sorry about that. Been a busy few months - built a motor and bought a car since my last post.

I reassembled the halfshafts I was working on before, but have another pair that I intend to rebuild once my car is down for the winter. I'll post some pictures of the process at that point if someone doesn't beat me to it.

[TXRFan]

Been a long time since I've posted here, but this thread is extremely valuable. I did the boots on one half shaft years ago on my street M3 and the M3 race car came due. Did both shafts over last weekend. A couple of observations:

The inner spiders on these shafts fit much tighter than the ones from the street car. The street car just pulled apart. Both of these had to be pounded out by supporting the spider loosely in a vice and striking the shaft with a hammer. You want to make sure you are supporting by the spider and not the cage or bearings.

There is no need to disassemble the outer joints. I used a small container and stood the shafts up with the outer joint at the bottom and repeatedly filled the joint with lacquer thinner. I would let it soak for a while and then poured the thinner out. About 3-4 rinse and repeats here. Used about 1/2 gallon of thinner. The poured out thinner was used to clean the inner joint parts. Finished up the outers with brake cleaner, blew them out, and let them dry overnight.

The previous time I did this I remembered how tedious the grease packing in the outer joint was. It took a long time to work the grease down to the bottom of the joint. This time, something hit me that worked extremely well. Support the shaft by the outer joint by clamping the outer joint in a vice by the spline shaft (wrap the shaft in a shop cloth and don't go too tight to avoid damaging the splines). The shaft itself goes straight up. Push the shaft all the way down in the joint. Fill the void with grease. Then cover the top of the shaft with the palm of your hand and pull the shaft up. The shaft is hollow all the way through and the other opening is inside the outer joint. The suction will pull the grease right into the joint! Rinse and repeat. I fully packed the outer joints in less than 5 minutes with this method.

As before, the ear of the Napa big band clamp on the outer joint interfered with the hub housing just a touch. A few small love taps with a hammer right on the crimp, pushed it in enough to clear the hub.

The hardest part of the job was getting the inner CV joint boot over the shaft with the inner clamp in place. Almost impossible, but doable with grease, turning, pushing, and cussing.

Great thread! It deserves a 3 year thread bump.

-Mike

[ewrjontan]

Amazing thread, quick question though. I am removing my axles and doing all of the boots. My driver side half shaft is pretty rusty (just surface). I was hoping to have it sand blasted and powder coated. Obviously, the outer cv joint doesn't come off. Is there any reason that I can't keep it covered during the sand blasting and is there anything in the CV joint that will be destroyed when in the oven during the powder coat process?

If it is a bad idea to have the CV joint go through the powder coat baking/curing process then I will just have the shafts painted.

[tjm3]

I wouldn't bead blast or heat/powdercoat. Just for the record, the blast media they use for powdercoating is different that regular bead blasting media. Bead blasting use just that, tiny, smooth glass beads that don't damage or etch. Powdercoating uses an abrasive with sharp edges that etch the surface so the paint can adhere. On a larger scale, it would be like using a handful of broken glass instead of a handful of marbles.

You can remove the inner cv joint if you have some resources available. Some pics here:

https://www.bimmerforums.com/forum/s...light=cv+joint

[ewrjontan]

After doing some more research last night, I am definitely just going to go ahead and paint it Thanks for the input.


Last question: The boot kits come with the clamps that sort of pull through a slot and fold over itself: not the typical oetiker/mushroom clamps. The tool listed in first post seems to be used for the oetiker/mushroom style clamps. How do you tighten these "pull-through" clamps? Just pull tight and fold?

[LockDots]

Yup. Pull tight, fold, then fold the sides in. You may have to hammer it a bit afterwards to get it to clear the hub.

[tjm3]

You can pull them tight, but you won't get them tight enough without the banding tool.
KD3191
KD3191.jpg P1080705_result.jpg

[LockDots]

I forgot about that tool. I had a shop do mine.

[ewrjontan]

Awesome, thanks guys!

[Cobra1956]

Working on a set of these for my track car. Not much grease left in the inner joints but easy to clean out. This has not been done since I have owned the car so it maybe the original grease. A great product for cutting grease of all types is Corotech. It is pricey but it will cut axle grease and remove it from clothing also. It works as an emulsifier. You mix it with warm water and it goes to work. A little agitation works miracles. IMG_1954[1].jpg This is the results from just soaking. You could make an argument for drying it, hitting it with brake cleaner and repacking the grease and calling it a day. No tear down or assembly. End of the day it will be way better than what has been ignored for years
I am also doing a little research on the outer joint. There is a clip in there very similar to the clip that holds your stub axles in the differential. I have an old set of axles I might sacrifice to see how tough this is to get off simply out of curiosity.
More to follow.

[Cobra1956]

Some fun reading supporting the idea that the outer will come apart.
https://workshop-manuals.com/audi/a1...y_joint_vl107/

Modern tech now gives us a tool if you are so inclined but checking with a local ATV shop they use a drift or a pipe with a slot in it.
https://www.youtube.com/watch?v=WfjqaDj_XME

[ewrjontan]

The outer joint comes apart easily. Once you pop the caps off (which have to be reused) it's more-or-less the same as the inner joint.

[Cobra1956]

That is kind of what I thought. Since I have two sets here I can afford to go exploring. As a side note I redid my sons 328i before sending him of to college and you could get axles from A1-Cardone for less that $60. They have been on the car for 8 years with no issues so for the price they are a consideration. For me I like tinkering with things and making a mess. Does anyone have any pictures of work done taking apart the outside joint? If not I will see if I can get some while I am doing this and add it to this thread. Lots of good info on this one. Thanks to all that posted

10 minutes in and I removed the two clamps. The outer was sort of staked so I hit it with the Dremel for a few seconds and it popped open. Pulled the boot back to find a healthy supply of 20 plus year old grease. Since there no noise issues I think I will just clean, grease and reload on the track car. I am taking pictures and will post later. The opening for the shaft is much larger than I anticipated and you should be able to get grease in there without any issues. If I was to take the cap off I would hit it with some thread penetrate and leave it sit for a day as it has sat for a long time and there is a bit of surface rust to contend with. Will pull caps on the second set for better reference.
More to follow

[tjm3]

Here's a link to an axle thread I posted a long time ago about the outer CV joints. There are some pics in the thread but I posted all the pics and two vids (.mov) in the other links.
Didn't have the time to pic and choose so I posted the whole lot.


Earlier Axle Shaft Thread

M3 Axle Shaft Rebuild

Video 1

Video 2

[Cobra1956]

Thank you for the excellent info. I think I can get by with the cleaning and adding new grease. The old stuff has lasted @20 years. So from the videos it looks like the outer caps are crimped on. Not going to do it but I assume a deft hand and a Dremel could cut them off.
Again that yo to all of you who posted info on this thread. I will post pictures of my mess but the bearings all look great so far and the outer was full of grease but the inners not so much.

[ewrjontan]

I removed the crimped cap with a screw driver. Just put a small flat head in-between the cap and the main piece then pry upwards. Move over a little bit and repeat literally a thousand times. Once you can fit a larger flat head it gets easier.

Then to put the cap on just take your flat head and tap the ends of the metal over the lip (on the main piece). Do opposite corners and work your way around. Time consuming but really easy once you get going.

[tjm3]

My rebuild was a bit excessive. I did it because up to that point I hadn't come across any rebuilds like that (outer CV) and because there was a lot of chatter saying it couldn't be done. I like those challenges.
I have the machinery and made the lathe tool with the little wheel to recrimp the caps, and so there you go. You can actually buy new inner and outer CV joints from GKN or from a company like

http://race.parts/Catalogue/Drivetrain/CV-Joints

but cutting and rewelding the the new outer to the axle stub could be an issue. Easier to just buy factory rebuilts even if you do end up with better parts. But at $500 the rebuilts are still worth it.
GS-P, a Chinese company, sells new axle shafts complete for about $130 each. I have a set, used them for a few miles just for fun, and have them on the shelf. They worked OK. New CV joints,
new axle but it's not hollow like the stock units, and mated to factory, used or reconditioned (they don't usually go bad) axle stubs. The friction welds are perfect.

[Cobra1956]

Finally finished this up today. Have a pretty good idea of how long it should take know and what needs to happen. I did not pull the outer joint apart but ran into my old BMW mechanic and he said he used to knock the outer joint off and clean them all the time. Few pointers that helped me with the outer end. I used mineral spirits on the driver side shaft and was able to clean it in less than a half an hour. Then shot it with a rinse of brake cleaner and allowed it to dry. Started filling the outs joint first. Used my heat gun on the cv joint to heat it up. Then held the axle upright with the outer joint down and started to pack it full. Then I compressed the joint and filled that space. The axle is hollow so I took my shop vac and and place it over the center hole in the axle on the inboard end (top). Between the heat put into the joint and the suction of the vacuum you could see the greas drop in the outer cup about 1/2 inch. I refilled with additional grease and called it a day