Clutch slipping, but there's no obvious cause

[Aikouka]

Well, as the topic describes, my clutch began slipping while driving and I lost just about all power. For a thread I made asking if it was my transmission that was at fault that also describes what happen, visit here http://www.dsmtuners.com/forums/showthread.php?t=138417 .

For a short description of what happened, I was driving and I heard a noise that sounded like my tire was flat (that low scraping noise), so I pulled over and checked my wheels and looked at the engine. Everything looked fine, so I went back on my way. The car after traveling a couple feet acted like it had no power. Well, the rest is history and in the link above, but now I've taken the transmission off and examined the clutch disc, the pressure plate and the flywheel. There's nothing bad but scorch marks from the clutch slipping.

I also checked to make sure the throw-out bearing was moving correctly. I moved it along the shaft, and it didn't bind anywhere, nor have a problem moving. At the moment, I'm not too sure what the problem was, but I was wondering if anyone's had problems like this or any ideas. If you want pictures or need more information about how everything was installed, just ask.

Thanks for your help!

 

[Aikouka]

I also thought I'd add that I didn't resufrace the flywheel before I put the new engine in the car (about 300-400 miles ago.) The flywheel didn't have any marks in it, but one thing I noticed is that the flywheel's contact surface is set apart from the rest of the flywheel. But the ridge (or offset) on it is VERY small. I doubt this would cause a problem, because the clutch started slipping suddenly, but I thought I'd throw it out. Oh, and I did clean any rust off of the flywheel's surface with an emery cloth.

 

[ben90tsi]

Ive heard that if you dont resurface the flywheel its bad news, but maybe thats just for the act 2600. If you skipped out on that and there are no other problems you can see, my best bet would to get that flywheel resurfaced.

 

[Aikouka]

Ive heard that if you dont resurface the flywheel its bad news, but maybe thats just for the act 2600. If you skipped out on that and there are no other problems you can see, my best bet would to get that flywheel resurfaced.

But wouldn't the flywheel not being resurfaced cause problems immediately? Because, like I mentioned, the car's been running great (except for a few leaks) until that incident. I read another thread and it talked about the transfer case, and how it can cause this problem over time if it's not functioning correctly. I thought my transfer case was leaking (there was always a glaze near it and on the transfer case itself), but I took off the fill cap, and stuck a belt valve's stem into it and pulled it out and it had fluid on it. But when draining, not too much fluid came out of it, but I'd assume that's because it doesn't really take a lot of fluid (Haynes says about .33 Qt.)

 

[Aikouka]

I took pictures of all of my clutch parts to give more aid to anyone who can help. Also, is it possible for me to take off minor parts of the transfer case? I don't mean seperating any of the three main parts, but there are two covers on the first section (the one that connects to the transmission), because I want to make sure my transfer case is okay.

Note that on the flywheel picture, the weird specs are just stupid surface rust that's already started to form after only a day. Gosh darned humid PA. Oh, and in that picture, I also circled scorch marks just to help point them out. I didn't circle the scorch marks on the pressure plate, since they're pretty evident. One thing I've always wondered, in my clutch pictures I took, you can see those deep "cracks" ... are those normal? Because my clutch was like that when I bought the car broken. To be honest, I wouldn't doubt that some part of the drivetrain is shot, because the previous owner blew a rod through the block ... so I have no clue how he treated the car, but I think I can make a good assumption.

 

[Aikouka]

Okay, well, I've practically narrowed the problem down to the transfer case or the center differential. Now, I didn't take the transfer case apart, since I'm definitely not a trained mechanic, but I did try rotating it, and it didn't seem to have a problem rotating it. My method of rotating it was shoving a file into the splines (note, not hard so nothing was ruined) and then I just turned the file. There weren't any irregularities, but I'm sure I wasn't spinning it fast enough to notice anything if a problem does exist.

Now, I'm not sure if it would be a problem, but could the VCU for the center differential be bad? Like I mentioned I had low grumbling/grinding the whole time, and suddenly there was a bang and the speedometer worked right again (the speedometer was reporting 70mph in 1st gear at one point.) Could the transfercase, which I assume may have been low on lube, even though I checked it afterward and it checked out fine, have ruined the VCU, and that was the bang I heard?

I really need some guidance on this problem, as I am going to be gone at college starting tommorow, and my dad will most likely be the one working on the car. He doesn't know much about AWD systems or DSMs in general, but can and has worked on cars in the past.

Thanks for any help that you can give me!