Everyone,

I have been driving a '88 740 w/ a M47 (8-valve NA) and 270k miles and just recently I have been getting a squeak or whine will having the clutch in. Previously I would get a very faint "grumble" or rumble noise when the clutch was in, but now it has gotten much more noticeable. When it first did it, I thought I had a belt squealing but it is definitely clutch related (i.e. it happens only when the clutch is in). The sound is intermittent in both duration and intensity so my guess is that this is the throw-out bearing, but I wanted to confirm with the collective wisdom of the board. I also hoping for some feedback on the severity of the issue...how soon do I need to address this?

As for repair, does it make any sense to do just the throw-out bearing? The clutch itself feels totally fine, although the adjustment on the cable is close to one end. A full clutch kit w/ bearing is $200 at IPD but I imagine the bearing alone is significantly cheaper. Just trying to be a cheapskate :)

Thanks in advance for the advice!
Brian

Everyone,

Just wanted to update this thread...decided to do everything and I am glad I did. Dropped the tranny and everything was in bad shape. The throwout bearing fell into two pieces, the clutch was worn to the rivets, the rear main is weeping, and the pilot bearing looked like this:
https://lh4.googleusercontent.com/-IKxXQWM9J28/URWJZwVL0uI/AAAAAAAAGDs/mEOZ3T-Wrgc/s640/IMAG0074.jpg

That needed to be replaced ASAP! As far as I can tell, this was the original clutch...I have most of the service records for the car and I didn't see any clutch replacement in the history. It is amazing that it wasn't slipping even after 270k miles and I am guessing the bearings just dried out after 30 years. Hopefully I can get everything back together this weekend and get her back on the road! Thanks everyone for the advice.

Brian

To remove the t/o bearing you have to remove the clutch assembly. Given the amount of labor involved, it does not make sense to reinstall used parts when a clutch kit is less than $200 out the door. Plus if the cable is near the end of its adjustment, your disc is probably worn and will need to be replaced in the not-too-distant future. This would mean doing the job all over again.

This is also a good time to replace the transmission mount and the rear main seal.

If you take out the transmission, you need to do it all.
Pilot bearing, throw out bearing, fly wheel, and clutch. Transmissions are something you only want to mess with once or twice over the lifetime of the car. The whole kit should come with everything. Make sure it has a pilot bearing. Doing it all will make you feel good about the whole thing. You will need torque wrench for flywheel bolts. Good luck.

i would maybe have the flywheel resurfaced, as a new one runs about $400.
Might consider doing a rear main seal while you are in there.
Paul