tomfree

When the car sits at idle with the clutch out, I hear a constant noise that sounds like a bad bearing. When the clutch is pushed in, the noise goes away. When the car is in gear and moving under it's own power, I no longer hear the noise, but that's likely due to engine/road noise, etc.

Now...a little more history. The car is new to me - an '89 S2, 140K on the chassis, motor was rebuilt by the previous owner under 1K miles ago, it has a new clutch (Sachs, no rubber center section) and lots and lots of other new parts. Essentially, the car has been significantly taken apart in the recent past.

I had a trusted local Porsche mechanic replacing the rear axles and doing some other work to make it track-worthy for an upcoming driver's school. He noted the "bearing" noise and described exactly what I had been hearing. He also said that when he was replacing the pass. side axle, it was an extremely tight fit, enough that he thought that the transaxle might be shifted a little to the right, slightly misaligning the torque tube, and therefore causing the noise.

Anyone experienced a similar symptom?
Was the torque tube actually misaligned?
Was it something else?
What did you do to fix the symptom?

Thoughts and opinions welcomed.

Jon Moeller

I would guess it is either a bearing in the torque tube, or in the trans.

-Jon

V2Rocket

Give the transaxle mount a good whack with your BFH.

Oddjob

Sounds like typical trans bearing noise (noise sounds like marbles rolling around in the trans case?).

Higher mileage with a spring centered clutch (transmits more engine vibration through to the trans, vs a rubber centered clutch) will make some noise at idle.

What youre hearing with the clutch out in neutral (drive line and input shaft are spinning), is mostly the big ball bearing at the end of the input shaft and 5th gear set rattling around. With the clutch in, the drive line and trans input shaft are not spinning, so there is nothing moving inside the trans.

Only way the trans is misaligned relative to the torque tube is if the two dowel pins were left out of the bell housing when it was reinstalled - and then there would have been significant problems aligning the input shaft with the drive shaft to install the clamp.

The trans is rigidly mounted to the torque tube, which is rigidly mounted to the engine. So the whole driveline would have to be misaligned - if that is the case, then there is a problem with the trans and/or motor mounts (collapsed or torn), or the car has been in a big accident and the body is bent.

SoCal Driver

I would look at the clutch work receipts to see if the pilot bearing was replaced.

tomfree

SoCal - I checked the receipts, and there is definitely a new pilot bearing. I don't think it's a pilot bearing since I hear the noise when the clutch is up.

OddJob - that's a very interesting perspective, and honestly one that makes me feel not quite so bad about leaving it alone for the moment. I'd love to file this under the "it's an 18 yr old car, it's not going to be perfect" file.

The car has a clean car fax and seems to be straight from what I can tell from being under the car on a lift. I don't see any of signs of unibody damage anywhere, but I am indeed just a layman. S

Since I've had some suspension work done, the car is due for an alignment. I'm going to have them check out the specs for chassis and see if the car is really square.

saad147

I have the exact same problem with my 91 S2. So if it is the big ball bearing at the end of the input shaft and 5th gear set is this a critical fix?
Could this lead to a bigger problem in the future? If I did get this fixed, typically, what would I be looking at in terms of parts & labor? hypathetically?
I just purchased this car and started noticing this noice a couple days back and would really appreciate any feedback given.

triscadek

I bought my 87S in '01 with 158K miles on it and the first time that I pulled up to an ATM where the sound could reflect off of the concrete on both sides and let the car idle in neutral I was worried if the car would even make it home.

After talking to my mech. about the noise, basically he told me that they all do it and explained to me what Oddjob said... they all do it.

5 1/2 years later at 235K miles the car still makes the same noise but now I just turn the stereo up.

I'd take a cross country trip in it tomorrow.

bjzorn

That rattle is actually normal. So normal infact that Porsche Denied all warrenty claims on that item back when they where new. 5th gear in these cars have a different tolerance then 1-4th so the 5th gear sets always rattles. I drove a 20K original mile S2 car with a new spring centered clutch(ABout 500 miles on the new clutch) here last week and guess what? yup in netural the rattle was there. Annoying yes, but its normal and won't hurt anything

Brandon J