Thread: Front tailshaft...URGENT HELP!!

Originally Posted by davros

Happy new year all!
Ok, I'm stuck. Front uni joint of the double hookes joint in the front prop spat it. It's all come apart fine, and I'm trying to put it back together with greasable unis. It appeared to articulate properly when I took it off, apart from the front spline is siezed, to be dealt with later.
What I can't seem to do is re-assemble the joint properly. We can get the two halves together without dropping a roller in the center bearing, but it will not go "togther" enough to allow the unis to be replaced (it's very close but the front uni caps will only go in when the shaft is bent at full articulation and the spring in the center bearing is fully compressed) - the hookes joint is left at an extreme angle and can't be made "straighter".
Also there appears to be about 1mm end play in the unis where they meet the hookes joint, but not in the tailshaft yokes.
The bearing specialist who took it apart gave it a good whack and scattered the center rollers, spring, and an internal washer that appears to have a lip on it, over the floor. All were recovered but Im wondering if the washer is in place in the center bearing properly? We have put it in so it "cups" the end of the shaft the rollers run on.
Any ideas why this thing won't sit in place much appreciated!
Cheers!
Dave

ALL over the floor!!

Yes they are hard to fit together. I haven't done one yet, but I have seen them reassembled succesfully and was told it was difficult. That washer worries me. Can we have some pics??

JC

I don't have the shaft it's 50km away!
The washer is not really a washer so much as a bearing "end cap" that sits under the rollers to stop them falling into the cavity behind the spherical bearing "ball". I'm pretty sure it's correct to face it so it cups the end of the bearing center shaft that is attached to the front half of the tailshaft, when this is slid into place. This bearing center is the part that appears to not be seating properly. At first I thought a roller was fallen and trapped under it and we re-assembled it many times under this assumption. But looking at it, it is too close to being "home" for a roller to be under it.
The center bearing was a bit dry and I was not present at its dismantling - can it be pulled out of place or is it integral with the rear tailshaft yoke?

Dave

Another thought...

If the splines at the front are seized, may it be that the yokes were "compressed" and when the shaft pulled again it destroyed the uni, but this allowed it enough play to flex properly when I took it off? So that when I re-assemble it, its not the bearing that is not seating but the yokes have been pushed away from the joints towards their respective tailshaft ends(bent)? Also this may explain why the yokes of the actual joint appear too wide by about 1mm - maybe they were forced to flex outwards, is this possible? The only strange thing is that the tailshaft yokes are not bent "out" - the unis have no end play there...

thats one of those things that I STRONGLY suggest that if its gone wrong you dont rebuild it you replace it...

But if you have to they can be done and it requires a combination of tongue positions 243m 572 and 82 at appropriate times to make it all go together.

If they have the slightest amount of play in the centering mechanism or in the U/J's it aint right and needs redoing. As a Its got to be done on the side of the road thing its a goer, once your starting to pay greaser hours for it it usually works out cheaper to buy the new one.

I don't understand ur numbers though... can you run over them for me?
Cheers,
Dave

What Dave said.

If you are in any doubt, replace it. I know they are expensive, but so is a failure, as it will take out that troublesome auto of yours in seconds, and the floorpan, etc etc etc.

As I said, I have seen them repaired, but I would advise customers to replace them.
JC

I have rebuilt mine a couple of times so I know exactly how it should be.

Make sure that the lip inside the ball is at the rear. The cupped washer is there for the spring that sits inside the shaft to push against, so give the spring the max room by having the washer cupped, not domed. The rollers go in next and then the metal ring at the outside end of the rollers.

You have not mentioned the spring. Is it stuck behind the ball? The ball can be rotated to give a useful view of what's behind it.

The ball can be removed but be careful not to damage the ring that holds it. I replaced the ball on mine last time as a kit - got it from WA but can get the part number if req'd. The seal is readily removed & replaced.

Edit: Sorry - you did mention the spring.

Originally Posted by davros

Another thought...

If the splines at the front are seized, may it be that the yokes were "compressed" and when the shaft pulled again it destroyed the uni, but this allowed it enough play to flex properly when I took it off? So that when I re-assemble it, its not the bearing that is not seating but the yokes have been pushed away from the joints towards their respective tailshaft ends(bent)? Also this may explain why the yokes of the actual joint appear too wide by about 1mm - maybe they were forced to flex outwards, is this possible? The only strange thing is that the tailshaft yokes are not bent "out" - the unis have no end play there...

My tailshaft yokes are narrower than my H-section yokes. When I used HS K5-L4R unis I had to re-use the original circlips on the tailshaft yokes and the supplied circlips (thicker wire) on the H section. When I used the heavy duty HS K5-A757 unis I had to use a press to get the circlips in place on the tailshaft yokes as the supplied circlips were the thin type already.

You could always take all the pieces to a driveshaft rebuilder. They can install a new ball kit if its needed.