1fastben Wrote:
-------------------------------------------------------
> What broke was the CV3 joint itself, not any of
> the shafts. It just popped out of the tripod
> thing, and I lost a bunch of the ball bearings
> inside that part as well. The braket seems to be
> fine, but I dunno. It was during a rally cross,
> and I wasn't quite turning lock to lock, but I was
> getting close.

If the tri brearing housing fucxored up?
did it spread out?

> One thing that I've considered might have some
> kinda' negative effect on the CVs is the Kaaz LSD.
> I didn't know it could be adjusted before it went
> in, and so my guess is that its at 100% lock, if
> thats how it comes from the factory.
>

It's not 100% lock, jack one side, whip off the wheel and place a bar accross 2 studs and lean on the bar, it'll slip.

>
>

---

John Vanlandingham
Sleezattle, WA, USA

Vive le Prole-le-ralliat

www.rallyrace.net/jvab
CALL +1 206 431-9696
Remember! Pacific Standard Time
is 3 hours behind Eastern Standard Time.

Please take pics of all the parts and post so we can figure out what happened. What manouver were you doing when it broke? What side was it on?

It sounds to me like you have too long of shock at full rebound and you pulled the thing out of the cup.

---

Lurch
Eric Burmeister
The west coast...of Michigan

suggested by Lurch at Rally WV is that our axles were flexing out of the outer CV cup. the retaining ring/crown/carriage/thingy that holds the balls -- was out of the cup, and one or more of the balls dropped into the rubber boot. this then caused shatering of the retainting ring/crown/carriage/thingy that holds the balls....

solution: put some washers behing the knuckle.

if ya cannot figure it out from there let me know.

btw- when we jack up our Mazda 323 with the front wheels off the ground, if i rotate the front wheels i can feel a CLUNK CLUNK in the front drive train. this is the balls in the CVJ carriage not being fully in place where they normally want to be. it is likely a factor why we have broken a front drive shaft in the past....we are working on this issue!

last time we broke down in transit to a regroup, at a right hand turn at a stoplight in the middle of town... no stress on the CVJ, the ring/crown/carriage had broken in a previous stage but the CVJ at that point in time was fully flexed, balls dropped out!


co-drivers: work out your legs
crew: pack an extra FWD shaft in the car


-Brian

Alright, lemme take the axle wreckage to work tomorrow and clean it up a bit, then I'll try to post some pictures tomorrow night.

As far as the ride height threads go, I set it pretty low in on the tube, about half and inch from the lowest I can go.

Well ya see, what happened was I was going around the final tight turn in a rallyx on really soft, dry marshy dirt when it broke about 2/3 of the way through the turn, but I was able to finish the run (yay!). It was a sharp left turn with plenty of rutting already built up on the outside lines, so the strut would have been on the compression stroke, but I may have hit part of the rut a little hard, I can't say for sure.

And I'm a little confused now. Andrew, do you mean that CV-1 and CV-4, being traditional, are the tripod type or the regular "other" type? The tripod is the inner CV isn't it? Because that's what seems to have failed, then about 100' later of clanking as I was towed to my "service area", the other outer section came out.

Thanks for all the help and inquisition fellas, I really appreciate it; just so ya know!

---

Ben Hetland
1973 Volvo 142 project car (with some cone-smashing on dirt in it's future, however)

"No. Rally Racing is a back alley sport filled with jackals, headhunters and thugs!"
-Pops Racer (Speed Racer movie)

www.utahrallygroup.com

My statement was that the inner CV joints or CV2 and CV3 are the tripod design where the outer ones CV1 & CV4 use a traditional CV design like the one below where you have ball bearings and a crown. See the image below.

If it is pulling out, it may be possible to get a bigger joint that will allow more articulation. I've talked with CVJ about this possibility with my car using a joint that will allow 22 degrees of articulation vs. the stock 18 degrees. But I've not yet had a problem with it. All the joints I've broken have been due to driving it with the welded diff too hard on tarmac. Then I drove it 100 miles to the event with one wheel drive so couldn't really tell exactly what cause the failure.

---

Grant Hughes

Alright.

There are 3 kinds of joints (at least). The one pictured above by Andrew is only going to be found on the outer ends of the axles. It allows movement in more directions (for steering's sake) but does not allow plunge.

The inner joints will have tracks that will allow plunge. That is, as the suspension moves thru it's travel, the distance between the trans and the hub gets shorter or longer, and the inner CV needs to take up the difference.

There are tripod joints like the ones above (3 "balls" are actually rollers and are fastened to the "race" on the inside and plunge in the "cups" on the outside), and there are other designs. Typical is the Lobro design like VWs and Porsches and most anything motorsport uses. Usually 6 balls with an inner and outer race and a cage to hold them in place. The races have angle cut slots for the balls to travel in. Porsche 930 joints are the typical pattern for most motorsport joints as they allow lots of angularity, plunge, and torque. (What we use on the Mazdaspeed3.)

If the failure happened when suspension was in compression, it is NOT likely that you pulled the race out of the cup due to shorting it...that usually happens when you have too much rebound travel.

If I read you correctly, it happened under full lock at full or near full compression. That's just a failure. Not a design flaw (unless you consider shitty axles a design flaw). It likely happened due to FULL WEIGHT of car on that corner + HARD ACCELERATION + SHOCK LOAD of car slamming into ruts. Now you know one of your FWD car's limitations.

For me it was 4L/kick on Burma. Snapped the 1.12" solid bar shaft right in half, but managed to finish thanks to LSD.

Go here and you'll probably learn something about axles: http://www.rcvperformance.com

---

Lurch
Eric Burmeister
The west coast...of Michigan



Edited 3 time(s). Last edit at 04/10/2009 06:56PM by Lurch.

I'd still like to see the photos of the parts. It would help us understand what failed under what forces.

The most durable setup we've found is not one that would be very roadworthy for the long run. RCV makes the front axles for bazillion horsepower CORR Pro4 trucks and they helped me make my system very dependable up to 450hp and 400ft/lbs. as long as we keep the shock loads under control. (Full sideways slide from gravel to tarmac under throttle with weight transferred to one side will twist the output spline thru the hub...Mexico Rec. Area-MFR)

The trick is often in the hardness of the metals used. The inner races and cups need to be softer than the balls and cages. How much softer is the question. Too hard and they shatter under shock load. Too soft and you'll burr up the ball tracks to the point where the joint hangs up.

If you're serious about finding the best axles, once you have something that works well, find a college with a metallurgical testing lab, get Rockwell hardness numbers for each of the parts, and you'll have something for a litmus test in the future if your favorite axles are no longer available.

---

Lurch
Eric Burmeister
The west coast...of Michigan