BMW M5 Forum and M6 Forums banner

UUC Clutch

781 Views 2 Replies 2 Participants Last post by  Pwdrhead1711
Ok, I am reeeeeaaaaallllllllyyyyyyy frustrated and I hope someone can point me in the right direction. Here is the background:

I recently installed a factory new/rebuilt motor in my 2000 E39 M5. I also replaced anything and everything that attached anywhere to or around the engine. I basically wanted my beast to be like new. One of the only things I did not replace when installing the new motor was the UUC flywheel and performance organic clutch, brake master cylinder or clutch hydraulics. The flywheel and clutch only had about 2k miles on it and other than some very minor glazing looked good. At about 1000 Miles on the new motor I took her to the track. The car was amazing, the new motor is putting out some serious HP. My buddy who is the driving instructor at the 2.5 mile 17 turn track I go to, said it was the strongest M5 he has ever driven, E60's included. He actually bested his best E60 lap time with it after two laps in the car. Once on the track, and once on the way home I noticed that the brakes were a little spungy to the point the pedal would almost hit the floor, but they were still working fine. On the track I thought they had just got hot. On the way home they were not hot at all so there went that theory. Since, that day they have never acted like that again. A few days later when the car was cold in the morning the clutch would slip in the upper gears. Once it was hot, no more slippage. hmmm Over the next few days and weeks it got progressively worse. I knew the clutch was basically new and was very perplexed by this behavior. I had ordered an AAW cold air/brake duct kit and a carbon fiber lip for the front bumper and dropped it off at the body shop I use. They called me and told me they tried to move the car but the clutch would not engage at all. We dropped the tranny and found the pressure plate cracked in half and the flywheel wear band warped so badly it looked like a spring washer after we unbolted it. I ordered a new hybrid kevlar/organic clutch kit from UUC, new wear ring for the flywheel, new slave cylinder, new input cylinder and all new lines, tubing and hose. Replaced it all. I had to remove the floor stop to be able to push the clutch pedal far enough down to get the new clutch to release. I have bled the system with a power bleeder from the reservoir down, I have bled the system with a pressure can from the slave cylinder up to the reservoir. I feel the forks engage at the normal point in clutch travel, about the halfway point, but it won't fully disengage the clutch until the pedal is on the floor without a floor stop. When released it engages in less than a half inch off the floor. When the car warms up it damn near won't go into gear. The premature failure of the first clutch was bizzare, and the new problem is frustrating. The first clutch seemed like it burned up from not enough engagement, and the new clutch doesn't want to disengage. Two different clutches two completely opposite problems WTF...
1 - 2 of 2 Posts

· Registered
78 Posts
Discussion Starter · #3 ·
I think I figured this out. Is there supposed to be a spacer plate between the flywheel and the crankshaft? I see some sort of spacer plate in the photo of the UUC light weight flywheel kit. Not sure but if my mechanic forgot to put this back in when he swapped engines the new clutch would not fully release as the flywheel would be closer to the engine and further from the slave cylinder...
1 - 2 of 2 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.