Porsche 944 (1985) - problems with transaxle clamp (drift shaft coupler)

[bryske]

Hi all,

I'm trying to exchange clutch on my friends Porsche 944 from 1985. All is gone well on dis-assembling and installing new clutch. Now assembling everything again, and I now have now struck on a problem, namely trying to re-install the transaxle clamp (drive shaft coupler) between the transaxle and drive shaft. No matter which of the two bolt I insert and tighten down, the other bolt can not be installed. It's like the transaxle clamp has shrunken, of course I'm aware that's not the case. But I know how to fix it, so are right no completely stuck. Very annoying. :-/
Have anyone had this problem and know the solution? Or just the solution?
All help is very much appreciated. :-)

A few pictures:

This is what I mean by transaxle clamp:


And a photo of the actual problem I've got:



BR
bryske

[944 Ecology]

1) remove both bolts from the coupler
2) move the coupler front to rear until the front bolt hole aligns with the groove in the torque tube drive shaft. Install the front bolt and tighten it.
3) While observing the rear hole in the coupler, use a prybar or large screwdriver to lever the coupler front to rear until the rear hole aligns with the groove in the transaxle input shaft. Install the rear bolt and tighten it.

The trick works because the torque tube driveshaft can move front to rear... the transaxle input shaft cannot move front to rear.

[OK-944]

Ha! George B. (944 Ecology) literally talked me through this in real time, by phone, as I was under my car! Again...George - Many Thanks!

[bryske]

Ahh, cool, I think what you're explaining, makes sense. I'll give that a try later today and hope and pray it works. :-)
Big thanks!

Btw - do you by any chance also know the torque the 2 bolts should be tighten with?

BR
Bryske

[944 Ecology]

[bryske]

Whauw! - you're a genius, that's great info, thx.

I'm currently trying to push the coupler backwards while the front bolt is tighten. But seems like the torque tube shaft won't move backwards, I then removed the coupler again to see if there was room between the two shafts, there's is plenty of room, but for some weird reason I'm struggling to get the torque tube shaft to moved backwards. That puzzles me alot...

[bryske]

Status - been struggling now for several hours, still no success. :-/
With the front bolt tighten I cannot move the torque tube shaft, to get it closer to the shaft of the transaxle, meaning I can still not install the coupler (clamp). Very annoying. :-(
Any help is appreciated....

[wwdwgs]

Take one-day break. Whenever I come to a "stop" with repair or installation, I take a pause and re-visit "the problem" next day or so. Mental reset, I guess?

[bryske]

Yeah, toke a break and left the garage (it's 20 min drive away from my home).
Here home, I'm thinking if the problem can be that I've exchange from the original (rubber) clutch, to a new clutch (spring-centered Sach clutch), when you shift from original clutch, do you need to adjust the torque tube shaft some how before installing it on the bell-housing?
Anyone know if that's the problem?

[944 Ecology]

Originally Posted by bryske

Yeah, toke a break and left the garage (it's 20 min drive away from my home).
Here home, I'm thinking if the problem can be that I've exchange from the original (rubber) clutch, to a new clutch (spring-centered Sach clutch), when you shift from original clutch, do you need to adjust the torque tube shaft some how before installing it on the bell-housing?
Anyone know if that's the problem?

Get a bigger lever.

I never had one where the shaft in the torque tube would not move front to rear.

You may have to remove the torque tube to investigate further.

[bryske]

I've tried with a pretty big pry bar, pretty sure it's stuck.
Could it be that since I've also exchanged the slave cylinder while changing the clutch, that the pressure is gone and the clutch somehow is "locking" it, TT shaft? (I know I'm potentially grasping for straws)

[wwdwgs]

stupid question, but still - did you orient the coupler the proper way: front to front (the straws)

[944 Ecology]

Originally Posted by bryske

I've tried with a pretty big pry bar, pretty sure it's stuck.
Could it be that since I've also exchanged the slave cylinder while changing the clutch, that the pressure is gone and the clutch somehow is "locking" it, TT shaft? (I know I'm potentially grasping for straws)

Well, at this point, if you cannot get it to work, have the car towed to a shop with experience. Part of being an amateur mechanic is knowing when to give up.

[wwdwgs]

In my "great" 'hood, most mechanics don't accept a partial job ("just remove the bearing") or when DIYer gets stuck.

[walfreyydo]

The way I did it was attach coupler to driveshaft (the side inside the torque tube), and inserted a pry bar through the smaller of the two inspection holes (shown in the below image), using the housing as a pivot point (red dot) and the coupler as the pry point (red line), and slowly pried the driveshaft forward towards the rear of the car. The driveshaft should be help pretty firmly inside the torque tube by the bearings but should move with some force. It can be a bit tight and wont move easily.

One note - The collar on my coupler actually broke when I was prying on it since its only tack welded in - I was able to re-weld it and complete the job (making sure the balance of the coupler was retained and the collar went back to the same exact spot it was originally) so do be careful and maybe avoid the collar if possible.

[bryske]

Originally Posted by wwdwgs

stupid question, but still - did you orient the coupler the proper way: front to front (the straws)

Not a stupid question, all question are welcome. :-)
I actually didn't remove it, left it on the transaxle shaft when I disassembled. So it was never of the shaft actually. Could have been a problem, but luckily I know that's not the fact.

[bryske]

Originally Posted by 944 Ecology

Well, at this point, if you cannot get it to work, have the car towed to a shop with experience. Part of being an amateur mechanic is knowing when to give up.

Well, not sure if you're helping or being a little sarcastic.
For sure not an expert mechanic on 944's, but have been work on 911's (911S, 911SC Carrera, 964'er and Boxster) for now more that 12 years. Done more than 10 full totally full restorations of classic 911's, plus a ton of more simple work on 911's, so wouldn't say I'm an amateur for sure.

So I'm not giving up - but I'll take down transaxle and TT again tomorrow or in the weekend, to see if I can find the problem. Was just hoping for a more simple solution since I'm merely helping a friend by doing his car, hence I was looking for others having tried a similar problem.

[bryske]

Originally Posted by walfreyydo

The way I did it was attach coupler to driveshaft (the side inside the torque tube), and inserted a pry bar through the smaller of the two inspection holes (shown in the below image), using the housing as a pivot point (red dot) and the coupler as the pry point (red line), and slowly pried the driveshaft forward towards the rear of the car. The driveshaft should be help pretty firmly inside the torque tube by the bearings but should move with some force. It can be a bit tight and wont move easily.

One note - The collar on my coupler actually broke when I was prying on it since its only tack welded in - I was able to re-weld it and complete the job (making sure the balance of the coupler was retained and the collar went back to the same exact spot it was originally) so do be careful and maybe avoid the collar if possible.

Good info, thanks. I actually mostly tried to using pry bar through the big hole. Since there was more room, and since I din't have a pry bar that was thin enough to go through the small hole. And screw drivers didn't really give any significant leverage to move the TT shaft. I'll try your suggestion tomorrow, after buying a suitable pry bar for the small hole.
Also I actually have pushed so much on the coupler, that I fear the welding might have taken som damage. How did you manage to ensure it well balanced after you repair? Just in case I need to do it after all....

And thanks for your helping info.

[walfreyydo]

Originally Posted by bryske

Good info, thanks. I actually mostly tried to using pry bar through the big hole. Since there was more room, and since I din't have a pry bar that was thin enough to go through the small hole. And screw drivers didn't really give any significant leverage to move the TT shaft. I'll try your suggestion tomorrow, after buying a suitable pry bar for the small hole.
Also I actually have pushed so much on the coupler, that I fear the welding might have taken som damage. How did you manage to ensure it well balanced after you repair? Just in case I need to do it after all....

And thanks for your helping info.

Make sure it goes into the exact same orientation as before. Try to use minimal amount of filler as possible and use small tack welds. I didnt seem to have any balance issues after reinstalling

[kdjones2000]

It looks like your TT shaft is a bit more forward than it should be, but you might be able to make it work if you try this:

1) Put in the front bolt, but don't fully tighten it. That will allow the coupler to still move front/back.

2) Move the coupler to the rear as far as possible and see if you can get the rear bolt inserted.

3) Tighten the rear bolt, then go back and fully tighten the front one.

That is my usual procedure.

Good luck, Keith