915 Experts "HELP"

[BSNMOE]

A few months ago, I installed a new Sacks "power clutch" package on my 73 S. The dam internal oil seal ruined my previous regular aluminum clutch. I had about 20,00 mi on it so replaced everything, but because the shift fork had only 20,000 on it I left it on.

I installed the TO Bearing shims as the 915 diagram indicates, and as the previous one was installed (washer and spring washer on one side and thrust washer with cir clip on the other)At this time I did notice a little bit more play in the bearing. I still had my old clutch assembled and it was a little tighter fitting bearing. I assumed that this was due to the Power pressure plate.

I installed and did find a little bit more play in the clutch lever when adjusting cable. I then removed the cable and was able to rattle and move the lever(which was also replaced along with the bronze shaft bushings, 20,000 mi ago. I adjusted and car shifted great. Drove for about 2,000 miles now and noticed a metallic clunk when driving slow over bumps in the road. checked sway bay, suspension, replaced mounts etc. Finally, I found that the clunk is my shift lever at the tranny has movement. For some reason now when everything is real hot I get a slight clunk. Not noticleable when cold, but, I can dublicate the clunk by hand at the lever. Adjusted clutch cable many ways and found that more than one inch free play works the best to quite things down.

The car still shifts great.

Could the shift fork bend because the Power Pressure plate put more stress on it?

Should I have used one more shim on the TO bearing?

Any help would be appreciated.

[revmax]

Not an expert, but Peter Zimmermann of RedLine Technik fame is. Check out his 915 tutorial. Might help? In any case, it's a great read on the 915.

Porsche Wiki

[BSNMOE]

Any ideas out there?

[Bob Kontak]

Originally Posted by BSNMOE

I found that the clunk is my shift lever at the tranny has movement.

Please forgive my ignorance. Where is the shift lever? Are you talking about the clutch/PP system or the transmission gear shift system?

[BSNMOE]

i meant to say clutch lever. At the trans where the cable adj. is.

[Bob Kontak]

There is a view port on the top of the transmission so you can look inside at the fork and t/o bearing. Probably not the easiest thing to do but a mirror and a flashlight will help.

If your fork is original, it is almost 40 years old. If it had a crack, the force of the new clutch may have allowed it to partially fail? Yo can tell from the port.

Was there a return spring that may be missing?

I just put a power clutch on last year and felt no excess slop when installing the release bearing.

Check this tech article out.

Pelican Technical Article: Replacing and Adjusting the 911 Clutch - Page 1

[BSNMOE]

Bob, My 73's 915 does not have a return spring set up. you adj free play at pedal to 3/4 to 1/2 in then adj floor board pedal stop. As my shift fork had less than 20,000 mi on it(actually when I looked up records it was 4 yrs and 16,000 mi) so I did not replace that.

It appears to me that it's a shim issue at throughout bearing. It shifts great, but has more play than usual at clutch lever. I look to see if i can spot the fork thru the peek hole.