TheSamba.com :: View topic

Wed Dec 07, 2016 11:24 am

Hi everyone! We need a little help with some issues we're having with our CVs. Our new 930 CVs started clicking very loudly (on the DS side) after only 4k miles. When we had them removed we discovered some wear that isn't typical. The DS side had much worse wear than the PS side ones but they all had wear in a section of the CV that doesn't normally get wear. I contacted Mike at GoWesty (where we purchased the CVs) about this issue and they've never seen this kind of wear and the Vanagon shop that removed them had never seen this kind of wear. The van sits 19 5/8" in the rear from center hub to wheel arch. The axles are not at a steep angle at all (we don't know the degrees of the angle but a photo is attached) We're at a total loss for how this happened and we're afraid it'll happen again in the next 4K miles. Any ideas?

Wed Dec 07, 2016 11:44 am

An axle too long or too short will do this. if on the inside side of axle, the axle is too long, if on outside side of axle is too short. change the axle length as needed

good luck

ps if you have too much suspension travel this could happen if axles are wrong length, size axles to accomadate the suspension travel extremes, the current axles may just fine to use if the suspension travel is reduced.

Wed Dec 07, 2016 11:50 am

How does one lengthen or shorten an axle? By getting a new one altogether? I believe this wear is happening on the outside side of the axle.

Wed Dec 07, 2016 12:06 pm

falkortheluckwagon wrote: How does one lengthen or shorten an axle? By getting a new one altogether? I believe this wear is happening on the outside side of the axle.

get a new axle, if too short a spacer might help (spacer between hub and cv) or reduce travel with stops.

I run stock stuff so cant be anymore specific, I am sure in the VW off road world there are many options, even offroad VW Bug, or sand rail sources maybe helpful. you might post your issue on the off road forum on the Samba, might get more help there than here.

good luck

Wed Dec 07, 2016 1:00 pm

Damn. That sucks.

The first thing I would do is call or email burley who more than likely built those axles and get his input.

I can't imagine the length is that far off but if by some glitch it is, any half knowledgeable metal lathe operator can cut and reproved the circlip groove easily.

When I installed my suby automatic I cut my burley axles down with a cutting wheel and regroovedvwith a cutting wheel Dremel.

Burley also sells replacement cvs, and bolts I believe.

I like swepco grease, I recommend it.

Added thought : is your rear suspension travel properly limited?

Neil2

Wed Dec 07, 2016 4:46 pm

Can you "dry" assemble that CV joint and check out if the balls are the correct size and move properly inside the race and the cage? It looks like maybe the wrong size was used when this CV joint was assembled and allowed the race to rub against the cage. In one of your pictures it looks like a dimple has been worn inside the cage opening, as if the ball was somehow stuck inside it. (I am using very careful language here. I didn't want to come right out and ask if the balls are too small :o )

Thu Dec 08, 2016 5:58 am

I agree with termuehlen. Assemble the axle dry without the boots. You can then move the control arm through its range of motion and see what the CV is doing. Is there any float on the axle shaft or is it binding/tight? The angle of the axle looks more than acceptable.

j.

Thu Dec 08, 2016 10:54 am

thank you for all of this, gents. will get to it and post results when we arrive in Tennessee and I have a space to work in.

Fri Dec 09, 2016 4:17 pm

furrylittleotter wrote: Damn. That sucks.

The first thing I would do is call or email burley who more than likely built those axles and get his input.

Neil2

Burley has NOTHING to do with the Go Westy kits. His only remark to me about them was the axels are too short for my build.....Syncro 16 length trailing arms. I had to buy a pair of Sway Away axels after measuring my axel length in my build. You results might vary.

To the OP....looks like axels are too short of too long....depending on where those wear marks were located on your roller cages.....if wear was to the inside....axels are too short....to the outside of cages....too long.

Fri Dec 09, 2016 11:03 pm

Unfortunately, your big fat thumb (!) was on the wear pattern I wanted to see, but I agree you should clean it and then with just slightly lubed balls on reassembly you will be able to see what's interfering. Totally dry and the balls will bind as they get to the ends of the ramps where you/we are curious about why that's hitting. I'm clear on where, just the why.

To me it seems as if something's machined wrong or the balls are indeed a wrong size. Are those ACTUAL 930 joints, or just 'sold as 930' joints? I ask because the cage holes where the balls ride seem kinda crudely unfinished rather than radiused. Random question.

There is also the question of proper assembly. I've repacked dozens of CVs and Birfields and the type you have can be assembled improperly. I think the wide noses of the star (innermost bit with your thumb) is supposed to point at the narrow noses of the outer race (not in any of your pics). Something that's counterintuitive. People want narrow to narrow in their heads (or possibly the opposite - now I'm questioning myself!). A new one won't go together wrong but if that's a rebuilt or non Porsche cage then anything's possible. I've never done it, but wonder if that improper indexing allows the inner star to plunge too deeply into the cage and grind on each revolution.

I don't think its axle length because there's a lot of slop in this joint longitudinally.

Following the thread. Drive safely.

Fri Dec 09, 2016 11:25 pm

IdahoDoug wrote: Unfortunately, your big fat thumb (!) was on the wear pattern I wanted to see, but I agree you should clean it and then with just slightly lubed balls on reassembly you will be able to see what's interfering. Totally dry and the balls will bind as they get to the ends of the ramps where you/we are curious about why that's hitting. I'm clear on where, just the why.

To me it seems as if something's machined wrong or the balls are indeed a wrong size. Are those ACTUAL 930 joints, or just 'sold as 930' joints? I ask because the cage holes where the balls ride seem kinda crudely unfinished rather than radiused. Random question.

There is also the question of proper assembly. I've repacked dozens of CVs and Birfields and the type you have can be assembled improperly. I think the wide noses of the star (innermost bit with your thumb) is supposed to point at the narrow noses of the outer race (not in any of your pics). Something that's counterintuitive. People want narrow to narrow in their heads (or possibly the opposite - now I'm questioning myself!). A new one won't go together wrong but if that's a rebuilt or non Porsche cage then anything's possible. I've never done it, but wonder if that improper indexing allows the inner star to plunge too deeply into the cage and grind on each revolution.

I don't think its axle length because there's a lot of slop in this joint longitudinally.

Following the thread. Drive safely.

Im pretty sure that the wrong axle length is driving the inner cv race into the cage, the cage is restrained by the outerrace which it self is retrained by the hub. it is pretty evident what is making contact, the wear marks show it, the cage is hitting the inner race. the wrong length axle will cause this. I am doing some 914 axles now and fitting one of the cvs in a way to replicate the wear pattern (contact) that is the photographs, the contact can replicate that of in the photograph by the cage being pushed too far out of the inner race. too short or long of an axle will do this. I am assuming that the correct sized balls and races and cage are used here.