Today I installed a new clutch into my 96Z. Stock replacement disk and PP. I also replaced the TO bearing, and the pilot bearing. Well just now I go to fire up the car. Fires right up, feels great with the clutch pedal pushed all the way in. Then I release the clutch and about half way up it starts vibrating, but not too bad. I thought it was just breaking in the flywheel. Then I tried to put it into gear, and as soon as I started releasing the clutch pedal in gear, everything started vibrating really bad. Felt like the tranny was going to break to pieces. Obviously I killed the car and now I am stumped.

My guess is either I installed the pilot or the TO wrong. Could one of these cause something like this, or is it something else? Also my flywheel was pretty rough when I got it resurfaced, maybe thats it?

Please HELP
Max

 

I was just thinking about the problem, and I thought maybe I installed the clutch fork wrong. What if I didn't snap it onto the TO and instead snapped it on just behind it, over just the input shaft. Do you guys think that might cause it? Damn it, I'm confused...

Update: After searching through the boards, I found a lot of people having this problem, but couldn't find a solution. Anyway, I went and tried some of the things I read. I tried giving it a little more gas before putting it into 1st and it worked. Once in gear, it vibrated less, just the same vibration I was feeling in neutral. I am starting to think that my clutch isn't fully disengaging during shifts causing the really bad shifting viration. However that doesn't explain the milder (but still very annoying) vibration with the pedal realeased.

Ideas?

Max

 

I don't think your pressure plate is torqued correctly. It may be loose.

 

Today I took everything off again, and I did torque the PP incorrectly. I redid it according to the manual to 22lb ft's and I think that should solve the really bad vibration while shifting (will find out tomorrow). However I don't see this helping the vibration I feel in the pedal while just sitting in neutral with teh clutch out. What could possibly cause this? I can think of three things: bad pilot, unbalanced flywheel, or unbalanced PP/clutch. Is there anything else?

Well I checked today during the teardown and the pilot looks Ok except for the dent in the side that is facing the tranny that I made while putting it in. Doesn't seem like it could cause problems though, right?

Also would a machine shop be able to tell me if my flywheel and PP are balanced. If not where could I get it balanced if the vibration is still there tomorrow?

Max

 

22ft lbs huh... I did mine to 50.. I wonder if thats bad...

 

The clutch needs to be torqued down in sequence, three passes at like 20, 35 and then final torque (52 for the LS-1), I don't have the LT1 specs in front of me but 22 ft lbs is too low.

If you cranked them down in one pass I would suspect you bent something.

 

After taking the tranny off and properly torquing the Pressure plate all the vibration dissapeared. I did torque it in several passes but my Haynes manual says 22 ft lbs for the 6-spd plessure plate. Can anybody confirm this? Damn now I don't want to drive it until I find out.

Also there is a weird noise coming from the trans. The only way I can describe it is like a big diesel truck idling. Anybody know what this could be?

Max

 

Pilot bearing.. or Throwout bearing.. alot of them make noise anyhow, doesnt mean theres something wrong..

 

What kind of clutch did you go with?

Sorry, just re-read that it is a stock replacement.

Well, the reason I asked is I'm having almost your identical problems/symptoms. Let me check my book and see what the torque specs are. 22 ft-lbs sounds a little low to me.

You are correct with 22 ft-lbs (according to my Chiltons book, not Haynes like yours, so thats two separate sources.)

I was thinking my problems were from a bad clutch (SPEC, and I have heard horror stories every since I bought it) But maybe I made a mistake as well.

I hope you find the problem. Let us know if you do. I'm sorry that I can't offer any actual advice though...

 

Yesterday I put everything back together and all the vibration dissapeared. The problem was a combination of the clutch disk not being centered right (stupid plastic allignment tool) and the fact that the first time I tightened the PP halfassed. If you take your time to get the clutch centered right, and correctly torque the bolts in a star pattern, you should be good. Good luck.

 

What about that "deisel" noise? Because every problem you described, I have. Right down to that noise. (all though I would have never though of describing it as a deisel sound... but after listening to it.. I guess it kinda did lol)

 

That noise is still there, it sounds like its coming from the TO bearing spinning on the input shaft. A couple of people told me it's normal and not to worry about it. The car drives well and I like the way the clutch engages, so I guess I'll have to live with the noise.

Max