New clutch slipping
 

Ideas? Brand new XTD clutch (sprung 6 puck), has about 5 miles on it. Bought it used from a member, dude apparently put it on, drove it up the driveway, parked it, and took it off. Stock 1.6 flywheel was resurfaced and balanced with weight ring machined off, pilot bearing is new, throwout bearing is used from a SPEC kit with ~15,000 miles on it, slave cylinder is brand new OEM, master is untouched OEM unit from 1993.

Pedal is a little light, however obviously even if the circuit wasn't bled at all, it should grip the same, since it only has to do with disengagement, which it's doing perfectly fine. It's engaging pretty close to the end of pedal travel, definitely more than my SPEC did. Slips right when boost kicks in (just under 4k rpms), shuddering noticeably but not violently while it slips. Only did this twice, once when I first tried punching it in 2nd, than once more to verify it was indeed slipping before I babied it home.

Does it just need to be broken in? Am I missing something? Or is it just fucked.

Here's the kit I have, sans flywheel:

XTD® STAGE 3 CLUTCH + FLYWHEEL 89-93 MIATA 1.6L MX5 :eBay Motors (item 200377577289 end time Sep-05-09 18:20:38 PDT)

Thanks for your help, my on going saga with this car continues...I already have a pinhole leak in my radiator to take care off, at least it's not leaking oil anymore.

If clutch pedal is light, I would think that the pressure plate is messed. But were you dumping the clutch, or were you making sure it was engaged before giving it full throttle?

it nearly impossible to slip a 6 puck disc....gotta be a worn/bad PP.

but i say you need to do this first:

http://boostedmiata.com/technical/clutch_adjustment.jpg

There should be no slip with a 6-puck at all when the clutch is fully engaged. Is there a step cut into the flywheel? (not sure if the 1.6 Flywheel has one) is it the correct pressure plate? When you bolted down the Pressure plate to the 6-puck was it easy? like there is not much clamping force? wow so many questions huh? Adjusting the pedal will change the release (clutch dis-engagement) point. but at this point try all the easy stuff before removing the tranmission again :(. Good luck with that, i feel the pain. Happen to me a few years ago :(

yeah i would bleed the system man. did you get any grease on the flywheel etc? If you have air in the system it could be pusshing the clutch apart and not letting you fully engage.

adjust the clutch pedal like i linked firsttttttttttttttttttttttttttttttttttttt

It's the right pressure plate, at least it looks exactly like the picture. It all looked completely unused, no dust, no oil or grease on it, no grooves on the friction surface. The flywheel was resurfaced at a very reputable machine shop, they've done all of my engine work in previous years, including another resurface job years ago, and do a lot of SM engine builds, I seriously doubt they did something wrong.

So just to be clear, follow the pedal adjustment, then bleed the system? Or just follow the pedal adjustment instructions and see if it slips still.

Holy crap. You have the worst luck of anyone I know. How exactly did you earn that Karma? Did you eat a twin while in the womb?

Hmm, I was 11.5lbs at birth....


To explain cueball's statement about my bad luck, my mishimoto radiator also developed a pinhole leak during this rebuild.

and the leaks, and the overheating, and the.....

Well it seems to be gripping amazingly now, after braineack's pedal adjustment suggestion. The height was fine, right at 7.25", although that's without carpet, so with carpet it'll be just under 7", and most likely within tolerance. But the free play was around .5". Adjusted that and went for a drive. It slipped once, but nothing after that. It's really hard to put in gear and shuddering at a stop, in gear, with the pedal in, so I'm assuming there's still air in the system and it's now not disengaging fully. At least that's an easy fix.

Edit: Oh, and the radiators like a little constant squirt gun now, yay. Sorta limited to short drives with it. At least I've kept my stocker if I need to drive it longer distances, just can't race with it.

You could also have a really bad slave cylinder, or a bad throwout bearing. Did you by chance replace the throwout bearing, and lube it? I had a throwout bearing go bad on me in a new ebay kit, and I did the pedal adjustment to help - which it did for a while, until the clutch no longer worked.

I had a similar experience when I put my new Happy meal clutch/flywheel in. In my haste, I failed to line up the 3 dowels that are on the flywheel that need to the match 3 holes to the PP.

My symptoms were just like yours but before I figured it out, I put on a new clutch master cylinder, braided ss line, bled the system, adjusted the clutch pedal.

You probably didn't mess up as I had but I thought it was worth mentioning. Oh, I only messed up the throw out bearing in the process.