oaros

Hi All,

as there was no history of flexplate check I did the flexplate and crank endplay check. All seems OK at 0.15 mm play.

Went on to check rear pinch bolt - was tight. So let's see if if it comes out smoothly and - it did. Once out, turns out there is quite a bit of wear on the bolt as indicated by fine rust. From what I can see it seems that the clamp has been worn away.

Car has exchange gear box from MB. Don't know when that was done - but not done to the highest standards (shift cable not properly in holder, cooler pipe twisted)

What next?

Thanks
Oliver

oaros

just had another look through Dwayne's TT rebuild; his drive shaft seems more to the front.
When looking through the worn away hole in the clamp I should be able to see the splines. I am not sure that's what I see in the photo in my previous post.

At the engine my drive shaft seems to show more spline than others I have seen...or am I just imagining this?

Oliver

tmpusfugit

On most cars there is about 1/8" of splines showing at the front clamp. it looks like your back clamp is done....needing replacement......

Black Sea RD

Hi Oliver,

The whole affair does not seem right at all.

It looks like the drive shaft was pulled toward the rear and the rear pinch bolt was forced through the necked down portion of the drive shaft than the groove it should be in.

Best,

oaros

Thanks Jim and Constantine,

You have confirmed what I was guessing. Too late tonight for anything else - I'll have a poke and clean tomorrow to see if I can get a better view.

Looking like TT and transmission out then. Weird thing is I am not unhappy about it, challenge - opportunity kind of. I was looking for a reason to do the Superclamp/Super Bearing thing. Throw in torque converter seal and bearing, K1 spring, check rear main seal as there is some oil contamination in the bell housing etc. Just means that the Winter project started early....no car fun in the Summer though....unless I find another 928....hmm

Cheers
Oliver

Dave928S

That's what bolts and couplings look like when they move forward or backwards, and ride up on the splines. Maybe someone previously did work on the front (pushed the shaft back to unload the flex plate) .. without loosening the bolt and correctly positioning the shaft ... which locked in what you see at the rear.

It seems to me that there's a preoccupation with the front coupling and flex plate at the expense of checks at the rear. The front one loosens ... so does the back. It happens on manuals too. I'm just about to replace the bolts on my GTS, after checking the position of the drive shaft within the torque tube and correcting if necessary. I regard those bolts as a routine service/replacement item because they stretch and loosen.

Here is a pic of what the driveshaft looked like on my 82 .... the front bolts were tight ... the back one wasn't ... and the shaft had migrated and allowed the rear bolt to ride up on the splines.

Mrmerlin

What your seeing in the first picture is the clamp and then the worn area is the input shaft of the trans, I would say you have a good rear clamp. No need to pull the trans,
SO first you need to order 2 new bolts,
then while your waiting for the new bolts,
loosen the front bolt and center the rear driveshaft in the input shaft groove, NOTE the clamp will move on the input shaft .
This can be done by tightening the front clamp and using a screwdriver on the flexplate
NOTE force the flex in the opposite direction to what you need so it can move a small amount in the opposite direction this may take a few times of prying and tightening. once the rear clamp and shaft groove is lined up then spray some cleaner into the clamp threads to clean them out,
use the front bolt if it has good threads to chase the clamp threads,
then install the rear bolt torque to 66ft/lbs use a dab of blue loctite on the bolt threads ,
then fit the front after prying FLYwheel back,
Note the rear bolt shank has been grinding on the driveshaft splines and it was loose at some point to allow this to happen,
please post pictures of things after you are finished
then install the front bolt and tighten it the same way you did the rear.

oaros

thanks, will order some bolts and have another look at it when I get back home tonight.
Oliver

oaros

thanks guys for calling this right. Cleaned a bit of the rust off, clamp can be rotated with my finger. Clamp is OK. Driveshaft too far back, similar to Dave's picture. I'll use MrMerlin's techinque for moving it.

fraggle

Wiggling, replace tighten and done!

You can pull the stuff and put it back in a weekend on jackstands, if you had too, but it's nicer when you don't!