Cowhorn

First off, thanks to all who contributed advice regarding my ordeal. Here's what happened.

I dropped the car off at noon on Monday. The mechanic took a look at it on Tuesday. He disassembled everything and found that the starter was, in fact, properly torqued and installed. However, the creacked area of the transmission casing (which I was informed about prior to any repairs were done) is impinging on the flywheel ever so slightly when the engine is cranked. Although this makes the noise I described in the previous post, he assured me that no damage will occur to the flywheel. He did mention that down the road an updated bearing may be in order, but he feels like this flywheel rubbing issue will not be a progressive problem.

He found no damage to the teeth of the starter or the flywheel, as someone had suggested I check. He found no shavings in the casing. He did see a shiny spot on the periphery of the flywheel and the cracked area of the casing that indicated to him that some rubbing between the two parts is occuring. Apparently, the tolerances in there are very small.

Again, there are no abnormal noises while the car is idling or driven. The clutch and transmission feel like new. The explanation makes sense to me. Does it ring true with you? And, by the way, the additional work was on the house, as many of you said it should be.

Thanks.

Peter Zimmermann

Jim: I'm really, really confused! A crack in the, I assume, bell housing? Welding wasn't possible when the thing was apart? Why/how/where did this crack come from? Why wasn't a die-grinder used to remove a little material to provide needed flywheel clearance? Is this crack near where the starter mounts? What "bearing?" And all of this happened post clutch replacement why? Seriously, Jim, I'm just searching for something here that makes sense...
Pete

Cowhorn

Hi Pete. I will try my best.

I believe the bell housing, yes.

Welding was apparently not required. To be honest I don't remember why. Possibly because there were no leaks.

The crack came from my fractured fork that got tossed around in there on the ride in to the shop for the clutch repair.

No grinding was done because he didn't want to thin the housing, and there is no contact during operation, only with cranking the engine.

I am unclear where exactly the crack is.

This all happened prior to the clutch being replaced (actually on the ride in to the shop).

I understand you and I are speaking different languages, but thanks for the assistance.

Gary R.

I don't understand what tolerances change when cranking the engine. The starter gear kicks out and engages the flywheel. The flywheel doesn't twist when the starter is engaged, does it?? I agree with Pete, the housing should have been repaired properly when it was sitting on the bench, welded and ground back to standard tolerance and clearance. No way is metal on metal contact "ok" in my eyes, and if its hitting, *something* is being ground down, regardless of what this guy is telling you. Have it fixed properly.

Peter Zimmermann

Jim: Gary echos my thoughts. A crack is a crack, and sooner or later it will get bigger because a crack will affect structural integrity. I've been running this thing through my mind all morning, and can't for the life of me understand why the torque of the starter can cause enough twist to make something moving hit something fixed. That crack, if severe enough to allow contact, might walk to an outer edge, or it might walk into the diff housing area, or it might not walk anywhere. I would never bet on the latter. Granted, I can't look at the damage/crack/shiny spot, but I can tell you that, in my opinion, there is a very good chance this deal is going to cost you down the road unless you address it now. You just can't put something like that together and think that it's going to self-machine itself into being OK. Every time contact is made unnatural loads are being absorbed by the flywheel, the crankshaft and the crankcase, and that's not good.
Pete

Peter Zimmermann

...one more thought. Did they take the starter out and bench test it to be sure its drive tip isn't bent?

Pete

Cowhorn

Seven months after the fact I took my car to another mechanic, highly recommended by several local Porsche guys, to have the noise diagnosed and treated. He got the engine and transmission out of the car and had a look around. Turns out the noise was likely coming from an ill-fitting shaft that goes through the clutch fork (my mechanic said he had never seen one like this one before!) and the "crack" in the bell housing was through and through at the inferior aspect of the housing. There was also a large defect in the lower part of the housing (2'"x 1") that was confluent with the fracture.

I have decided to have the bell housing replaced because to repair it would be inadequate in the long-term, in my opinion.

Live and learn.