I am having a bear of a time diagnosing my latest clutch trouble. I have had clutches go out and I know what that feels like. I know that if the PP is weakening, that the heavy portion of the pedal movement might move. I know if the disc comes apart that the engagement point might move. But this one is confusing me.

A little background. Went to the BMW event last Saturday with my friend Dean and launched the car harder than normal. 5500-6000RPM with a little slip of the clutch and all 4 wheels spun a little and then grabbed hard. No axle hopping or excessive slippage from the clutch. After my 8th run (Dean had run 4), I went for a quick cool down down the road to get the oil temps back down and cool the brakes. It felt fine. After I gave it to Dean, he shut it off because of the long wait and let it sit for about 10 minutes. When he got back in the clutch engagement was very high. It wasn't slipping, so he went ahead and raced it. He had a intercooler clamp fail and had to abort the run. We thought we fixed it and he went out again. No slipping and the clamp blew again, so he had to coast back in. I fix the clamp to limp home and when I try to take off the clutch won't fully engage. I tried to adjust the pedal, but that didn't help. The pedal pressure is fine and the car makes no noise at all. Looking at the slave cylinder, it is moving plenty. At the top of the pedal throw, it still feels like the clutch is slightly disengaged. I limped it home and tore it apart since it didn't look like bleeding it was the solution.

Now that I've taken it apart, it looks pretty normal (I've had the tranny out in this car 3 times). I snapped a few pictures and maybe one of you has an idea. I hate to order a new kit (Minimum $480) if I only need a disc. The clutch in it is used on road race cars that make 450AWHP. Plenty of people drag race with it and I have now only launched it about 10-12 times and have about 2000 miles on it. It shouldn't be failing now. Even so, it didn't fail in the same manner that most clutches I have had fail did so. It went VERY fast and with no warning at all. The only issue that I had with this clutch was that during the install, the TOB has to be forced in to the PP since it is a pull type and I bent the arms on it (see pic) and had to remove the tranny to straighten them out so that the clutch lever could force it in to the PP. Since then it has never given me a problem.

Here are the pics:

Flywheel (Hotspots, but that's normal):


Disc and PP as they were removed:


PP face:


Other side of disc:


PP Teeth:


Thow out bearing (I broke that arm off of it during removal. Those ar ethe arms that I bent during installation.):


Any ideas?

 

U really worked that thing. Its organic, it won't last with all the launching (too much slippage).

Is that the Stock flywheel, Stock PP and an aftermarket clutch?

Is the PP really that bronze color or is that just the camera flash?

 

Disc looks fine but looks like excessive heat on the flywheel shouldnt be discolored.. if it looks blue there are probably micro cracks in those areas.... pressure plate looks like its seen high temps.. but id replace the Flywheel.. minimum

 

oh thats the PP .. if thats the PP then the flywheel must look roasted.. mine was smoked and didnt look that bad.. got 12k out of it..

 

It is the Road Race X Clutch and stock flywheel. I can have it turned and it should be fine. I've had ACT clutches in DSMs and they never crapped out after 12 launches total and 2000 miles. I beat the hell out of them. It's just strange the way it went. No waring at all and the pedal pressure was fine. I think the PP and disc are fine. Maybe the TOB or something kept it from engaging fully. I am just not sure since there is no visual evidence of the exact failure.

 

Hmm mines the Noname clutch , is that the same as the X... i got the SS flywheel from them .. ive got about 2k on it and no launchs .. so its nice and broken in

 

how about the clutch fork? maybe the slave cyl isnt working properly

 

Maybe the flywheel and PP are worn down too much? The stopper studs on the PP are hitting the flywheel with plenty of meat still on the clutch?

 

Bingo... winner! If you look at the first pic you can see where the studs (rivet heads) hit the flywheel. Once that happens there is no clamp left since the pressure plate bottoms out. Actually it is the disc that is worn too much. From the looks of it, heat is the enemy here, unless that heat came from abusing it after it started to slip.

 

thats why you usually replace the flywheel when you put a new clutch in there.. just get a new flywheel should be fine .. oh and a new tb... good luck

 

My opinion is it was a throw-bearing issue.
I've seen PP and flywheels look worse than that and still perform fine.

If you look at the last picture of the PP, the TO bearing race looks all mared up at the top, like the fingers binded and ended causing the clutch not to fully enguage.