Hey guys, I've got a bit of a problem. I have a 1984 720 4x4 with the Z24 motor in it. I've done a few mods and a bit of maintenance, since the PO didn't do much. I had 5th gear go out on my old transmission about a year and a half ago. I was fine with since it was still good to drive around town. Well, fast forward to recently when I bought a parts truck. I had to replace the transfer case, did that. I pulled the known good tranny out of the parts truck, inspected it, replaced the seals, put new fluid in it, and then installed it. I went ahead and put a new Exedy/Daiken clutch in it as well. Well, a few weeks later the clutch disk separated from the clutch hub. Ok, it only had like 4 rivets holding it in place. Ok, maybe it was just a bad/old design. I replaced the clutch disk with an OEM Exedy/Daiken disk and on Saturday night I had the same thing happen after only about 2 weeks. Now, I'm not hard on it at all. I was still in the break-in process and hadn't gone off road or anything. Since I'm a mechanic I am able to get parts that I need and use a lift to do the work that I have to do. I have no problem with that.
My question is, has anyone had this happen to them? It seems very strange that I have had this happen to me twice now, all within 3 weeks. Me and my boss have come to the conclusion that something must be wrong with the pressure plate. We are going to warranty the parts through our supplier and get a new one here for the weekend, but it just seems strange that this has happened. The rep that we deal with through our supplier has never heard of this either. Any ideas?


Jon

did you re surface the fly wheel.??

Yes.

the pressure plate was new ,correct.

sometimes they suggest you clean the surface of the flywheel and pressure plate surface with a cleaner/degreaser.

it does seem to be a strange occurrance.

were the failed clutch disc the same make ??


could there be a overheating of said surfaces??

Yea, I cleaned everything with some brake clean before reassembly. The only manufacturer that I can get through my supplier (WorldPac)is Exedy/Daiken. Daiken is usually pretty good, and are an OEM supplier. From what the last clutch disk looked like, I couldn't see any discoloration from heat, it looked more like it just sheared the metal, that connects the hub and the disk, right next to the rivets.
I have yet to pull the current one out, due to holidays and not having a real "want" to have to do it again. It's weird though because the amount of pedal travel to disengage the clutch requires the entire travel length. It's disengaged when the pedal is completely on the floor and if I put any pressure on the pedal you can feel the throw out bearing moving against the pressure plate fingers. I think, it may have something to do with that and I will be replacing both the master and slave to see if I can get the amount of pedal travel down to what I would call "normal" and not the huge amount that it is now.

Sounds like you may have the disk in backwards. The hub is offset. Not sure if that particular one can go in backwards, but I have seen folks do it from time to time. They return the parts saying "This was rubbing on that...". I would flip the disc around and tell them " It goes THIS way."
It is an easy, common error. Maybe it got YOU this time.

Aside from that, I have not heard of anyone having that problem with an exidy clutch. Pretty sure that is what I put in mine.

Did you replace the pilot bushing when you did the clutch? If not, it may be off-center.? Just grasping at straws, there.

It's definitely in the right way around. I even pulled the clutch/pressure plate off a few times to make sure that everything was lined up. I will be pulling it apart either tomorrow, Friday, or Saturday. I will get pictures then and throw them up on here for everyone to see.
I'm going to throw a straight edge on the flywheel to make sure it isn't warped and take my spare flywheel to the machine shop and have them resurface it just in case.

quote:

Did you replace the pilot bushing when you did the clutch? If not, it may be off-center.? Just grasping at straws, there.

that's what I was thinking, or you may have grazed it putting the tranny, this happened on my 76 Blazer the first time I did the clutch.