Post Re-Build Squeal

[Groesbeck Hurricane]

I am still chasing an irksome squeal on an '83 SC 3.0 redone to stock, no performance modifications only safety upgrades. Basics:

Engine leaked after re-build so I went back in and tidied up, corrected some errors.

Motor sounded nice after re-build, shifted well with power equivilent to prior to re-build.

Re-installed motor several times after taking back out to correct leaks.

Each time motor replaced, I have had squealing from the area where the clutch plate exists.

Tried: Removal and replacement of motor
Adjusting clutch cable
Adjusting clutch pedal
Adjusting placement of the small arm
Adjusting distance of travel for the clutch cable


I no longer believe the throw out fork is positioned incorrectly, I have done it too many times.

Symptoms: Squeal at under 1900 RPMs at idle
Squeal increases when cable is incorrectly distanced
Squeal disappears at ~2000 RPMs
Squeal not noticeable under load
Removed cable and started car, noticed a slight scraping sound from the area of the throw out bearing, clutch plate

Any and all suggestions welcomed! I am generally working on this by myself and have limited time frames where I can work on the dear. I am at the end of my ideas.

[dporsche74]

maybe the new pilot bearing not lubed enough?

[lendaddy]

i am voting throwout bearing. Can you change the squeal with light pressure on the clutch pedal? I had mine go and it was exactly as you say. I think the engine has to come out again. Did you replace the clutch?

[Groesbeck Hurricane]

The clutch is about 30,000 miles old with the exception of the cable which is 3,500 miles old. I did not apply more grease, but I will take out and try this. Heck, I'm willing to try almost anything...

The time I had best results, the squeaking would go away when the clutch was depressed or the RPM got over 2000.

Should I remove the clutch and put back on with a different torque wrench?

[lendaddy]

For what it is worth you dont grease the bearing, it's either good or bad. It's not expensive so just order one up.

[Groesbeck Hurricane]

Darn motor...

OK, ordering the throw-out bearing. Is there anything else I should be ordering at the same time? I'm thinking new fork... Any other opinions?

[lendaddy]

With an SC there are I believe some clips that are associated with the throwout bearning that are needed. Others will know more.

[john walker's workshop]

a new bearing for sure, and replace the fork because they wear a lot where they pull on the bearing, and they tend to crack too. i generally replace the fork with a clutch job. no clips on those.

[Groesbeck Hurricane]

Thank you John!!

I will place the order today. It is just hard to believe I need new parts after 30,000 miles, but maybe the PO was ripped on this part of the clutch job also? At least the disk and plate appear to be in great shape...

[lendaddy]

A mis adjusted cable can I belive to bearing failure, Miles mean little to your TO bearing rather time engaged. Do you tend to ride the clutch alot? Hey, it happens

[Groesbeck Hurricane]

Daddy,

I do not think that I ride the clutch, but I do know that I sometimes apply the accelerator a little too quickly and let off the clutch a little too slowly. I had to lay off standards for a number of years due to knee injuries. Good thing my wife is a Chiropractor by training, if not by trade.

I had also replaced the cable after the first re-build attempt and adjusted to exactly 25cm of travel. But then again, like you said, conditions are more important than time! And I could have damaged the little bugger when it wasout of the car. Also the PO's mechanic could have re-used the original, they screwed some other things up too.

I really appreciate the thoughts, I'll spend some more time practicing my shifting!

[Groesbeck Hurricane]

From Pelican to deliver Friday or Saturday:

Throw Out Bearing, 9 Bolts, Fork, Fork Pins, O-Ring for Guide Tube, Roll Pin for Release Fork, and Backlash Spring (to replace the one that fell off on the quick test spin).

I'll post back Saturday night or Sunday. Wish me luck!

[lendaddy]

David,

I was not implying you were a poor driver at all, just that some people tend to ride the clutch after years of driving indestructable Hondas and such. Also, I am sure this will rid you of your squeal. I had a destroyed T/O bearing as well and though I am not sure if I was a "clutch abuser" I am much more conscious about it now. Best of luck.

[Groesbeck Hurricane]

Daddy,

I didn't take your suggestion as an implication of my driving ability. No personal anything taken. You did make me stop and think of bad habits I have while driving which is a very good thing. Thank you for your suggestions! I was hoping to spend more time behind the wheel, uhm, practicing though...

[Wayne 962]

You described a bad throw-out bearing to a tee!

-Wayne

[Groesbeck Hurricane]

Throw out bearing was bad, very bad!

Replaced and started to mount motor back on transmission.

1st mistake, did not take transmission out of vehicle.

Tried remounting motor several times and on the fourth try they slid and mated easily up to where the studs were out the back of the bell housing just enough to put on nuts. Motor did not want to slide on any further. Pushed for quite some time, re-tried mating, had the same results. Put nuts on, tightened the nuts and the motor and transmission pulled together snugly.

Adjusted clutch cable and had the same squeal again after depressing the clutch. Noted the RPMs diminished and the motor died when clutch depressed.

Readjusted to the high end of the cable travel (1.0 inch) and the squeal went away and the motor did not die when depressing the clutch. Clutch felt good. Could not engage gears (grinding)

Readjusted the cable to 1.025 inches, no squeal but the pedal shakes when trying to engage. Clutch felt weak at the end of travel. Unable to engage gears due to grinding.

Thoughts, opinions? I really don't have money to pay someone else to do this job. And it really shouldn't be that difficult...

[Groesbeck Hurricane]

Went through the Porsche Service Manuals and the Bentley and decided to adjust the clevis on the clutch cable. I tightened up on the cable and tried to check adjustment. The clutch spring would not return on its own. I gave more cable and tried again, same results. I have adjusted back the clevis to the "original" setting and am back to the same problem.

We did hear a metalic pop at one point (I have a friend who came into town to help out this weekend). It appears as though the angle on the small arm increased.

I do appreciate any thoughts or opinions.

[Wayne 962]

Sounds like you didn't make the trowout fork properly with the TO bearing when you mated the engine and transmission together. Many, many people have this problem. You need to make the tranny and fork together as you are putting the engine together. Unfortunately, it sounds like you muscled it together, and you may have damaged the fork in the process.

This is the number one argument most people have with me about not pulling out the tranny. I personally didn't have any problems, once I knew what to do. I think I took a bunch of pictures, but I don't think I ever got around to completing a tech article on this subject...

-Wayne

[Groesbeck Hurricane]

Wayne,

Thanks. When mating the two I looked through the hole and ensured the top of the fork was in the top groove of the bearing. How do you know when the fork is correctly situated? I had always thought if the top was situated correctly then the bottom should be in place.

I will be removing the motor (you know, this part I'm getting really good at) tomorrow evening. I would appreciate any advice on the re-mate...

[Wayne 962]

Hmm, if you looked through the hole, and made sure the fork was inbetween the two grooves, then you're ahead of everyone else, and you *should* be okay.

Must be something else then...

-Wayne