Montana 911

This forum is great and much has been learned about my car, except for the current major problem. Does this sound like the fabled dual-mass flywheel issue or could it be a broken clutch disk? Either seem to involve an engine pull and a trip to the bank.

The clutch went out a few days ago, it had to be towed home. The car is a 1991 911 Carrera 4 with just under 65k miles. It will go to the shop next week and I am hoping to get some information ahead of the trip.

When it went out, the clutch pedal went to the floor and stuck there. There was no pressure. After stopping the car at the road side, I pulled the clutch back out but the clutch will not depress past about 1/3 of the full travel.

The car was started last night and when I went to *gently* engage the clutch, there was a terrible grinding noise. Of course it never engaged.

Prior, there has been substantial clutch chatter for some time. At least I think that is what it was--with the engine on, stopped but in first gear, and slightly depressing the clutch there was a definite vibration in the pedal consistent with the RPMs. The car also shuddered starting in first gear if I was not very careful.

Also, before the clutch went out there was also a "braaapppp" metallic noise coming from the engine or transmission. Based on what I have read this could also potentially indicate a failing DMF, but I am not sure.

Thank you very much in advance for the help and advice.

Sincerely,
Andrew

Marc Shaw

Ouch.

That sounds like what happened to me last year when a shift rod broke and took a few teeth off one of the syncro's. Hopefully you're luckier.

Marc

Steve Weiner-Rennsport Systems

That rather sounds like a release fork/shaft issue. Might be broken due to bushing seizure; you will have to look inside there to be sure.

Montana 911

Thanks! I was hoping you were going to say to change the brake fluid and that would take care of it.

Makmov

Yeah kind of sounds like a release fork. DMFs rattle when you shift or shut the car off.

carlskisWP

MT, Can you clarify what your "clutch chatter" was? You said when in first and stopped you would slightly depress the clutch and get vibration. Did you mean slightly release the clutch (let up on the clutch pedal)? For comparison I get a vibration in the clutch pedal (consistent with RPM) when in gear and slightly depressing the clutch, which goes away when the clutch pedal is fully depressed.

Montana 911

Carl,

I believe the symptoms were exactly as you mentioned: clutch pedal vibrated consistent with RPMs when in gear and goes away when fully depressed. Unfortunately I do not remember if it did this when out of gear too (it seems I would have to put my right foot on the break to check this as my driveway has a slope, but it also seems maybe I just checked when in gear right before taking off). The engine could be revved a bit to keep the car from shuddering so it did not bother me too much. One other item of note, a few times recently the car seemed to be down on power a bit when in second or third gear and accelerating. It was not substantial, and hardly even worth mentioning. It acted almost as if it is in need of a tune up. I do not know if this is related.

Now the clutch cannot be depressed more than about 1/3, with or without the engine running, with the car in neutral. It is unclear why it when to the floor when driving and now this is all it does. I have not tried first or any of the gears, but maybe should tonight (with the car off, of course)? Trying to depress it with it running sounds like a lug nut and crowbar smoothie.

Is it possible the problem is more along the lines of a bad clutch master cylinder or slave cylinder?

Thank you!
Andrew

darth

Based on the info provided, sounds to me like some of the fingers on the pressure plate have let loose and are interfering with the throw out bearing. There's an inspection hole which may allow you to determine what is broken before dropping the transmission/engine.

carlskisWP

My limited research on RL seems to indicate that the pedal vibration we are describing could be a worn release bearing (aka throw out bearing). But others have described a loud squealing as the release bearing gets worse. Anyway in your case it now sounds like something else clutch related has failed and not a master/slave cylinder. Please keep us informed - after you drop the engine and go to the bank. I sense clutch work and a trip to the bank in my near future as well.

Montana 911

Thanks for all your thoughts. My bet is with Darth on broken fingers in the pressure plate--of course the Dark Side would loom over these repairs. :| I started it briefly this weekend to listen for more noises and also heard a rattling noise when turning it off. $#@% DMF? The car will go to the shop in the next few weeks to see what is up. I will let you know who the winner is.