Drive Train

Clutch Damage: Torque Tube Moved Forward

Clutch Damage: Torque Tube Moved Forward

I removed the clutch cover from my 86.5 for release bearing replacement, and found that the forward end of the stub shaft (the large clamp) has been rubbing severely against two bolts that attach a plate across a frame (very technical) to the point where the bolt heads are virtually gone, and I do mean GONE. Finding the means to remove and replace them is going to prove difficult! I also suspect that the groaning/squealing I have been hearing is probably related to this problem, and not the bearing.

My question: What would cause the shaft to move forward this much? Is this movement some function of normal clutch wear, and in my case, excessive wear, or something entirely different?

I have a bad feeling about this, so all replies appreciated!

Suffering performance withdrawal symptoms....

86.5 Indischrot 5-speed

If your pilot bearing is shot and either or both couplers that clamp the torque tube to the central shaft or the transaxle are loose, then the central shaft and possibly the torque tube may have crept forward.

79 hybrid
84 stock

Yes, indeed, it now appears that the torque tube shaft is the culprit.

Has anyone else experienced this "creeping" shaft that moves forward within the torgue tube housing?

I'm moments away (well, some moments anyway) from starting the awful removal process, and would be delighted if someone came forward with a 5-minute fix that I somehow missed (hope springs eternal).

Barring that, any helpful hints on pain-free TT removal will be welcomed!

86.5 Indischrot 5-speed
Very blue owner :(

If you have been following my posts, I have been experiencing a clutch/torque tube problem that is almost answered, though not resolved.

Thanks to advice from Mark Anderson, I checked the rear coupler on the torque tube, and it appears that the coupler was loose allowing the shaft to "work" and wear down the splines. As it did so, the shaft inched forward to the point where I see what I think is the bolt groove emerging from the female end of the coupler.

My question (there really is one) is this "Is there more than one groove on the gearbox end of the shaft? I suspect the answer is no as I can also see what appears to be remains of splines!

I have attempted to remove the bolt to verify if the "groove" is where it is supposed to be, but the bolt is "weld-tight" which I would expect if it were worn and in an interference fit. This little jewel of a problem will
be interesting to overcome!

It was mentioned that a problem like this is rare, so I guess I have a "rare" shark!

So, here's a summary of the problem.

The rear coupler bolt apparently loosened, and allowed the driveshaft to "work" inside the splines. Over time it eroded the splines and somehow caused the shaft to inch forward. This is hard to figure as the press fit of the shaft into the bearings would (I thought) have prevented any fore/aft movement.

As it inched forward, the bolt wore a flat spot (sort of) back along the splines. This flat spot was the only thing preventing the shaft from rotating completely in the rear coupling. Once the bolt was removed, the
shaft could be spun quite readily!

To get the bad shaft out, I had to pull the transaxle and torque tube without being able to slide the front coupling off the stub shaft. This was not easy as clearance is a big problem.

With the torque tube/transaxleout, I next had to cut through the torque tube just in front of the transaxle and slice the driveshaft. This allowed me to reomove the torque tube proper. and then get to the frozen rear bolt. Getting the rear bolt and shaft remains out proved easy. Amazingly, the input shaft to the gearbox was undamaged!

At the front of the assembly, I had to replace the pilot bearing as the creeeping driveshaft had punched the guts out of it! Removing the remains of the bearing was a real bear. Also affected was the throwout bearing sleeve and the bellhousing where the vibrations up front (from the failed pilot bearing) loosened the sleeve and allowed it to "fret" the bellhousing surface.

All in all, my parts costs were low, but my "internal" labor costs were exceptional! I estimate I have spent 30+ hours getting this problem fixed. This includes all the "special" tools I have had to fabricate to remove items in a non-standard fashion.

I strongly encourage owners who have had a torque tube removal to have the coupler bolts checked for torque at some rather short interval, say 500 miles. To have this extensive a repair done at a shop would have been devastatingly expensive!

Warm regards,
86.5 Indischrot 5-speed

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