Help. Transmission question. why do wheels spin with clutch in--sometimes?
 

So my shifting into 1 and 2 and R has been notchy but inconsistent for a while. The clutch is new and set up per Tilton's instructions-- full release plus a quarter inch of pedal travel.

I can put the car in gear (motor off), jack up the rear, and spin the wheels by hand with the clutch in. I *know* it disengages and the hydraulic system is fine (and <3000 miles old).

When I start the car, rear end jacked up, brakes off, in neutral nothing happens. just idles normally.

When I push in the clutch and put it into gear, nothing happens. For a little while. Then the tranny WHIRRRS and the wheels slowly spin up.

I can stop them with the E brake or brake pedal and the engine doesn't die. It may dip slightly--but hardly at all.

It does it in 1, 2, 3, and R I think.

If I leave it in 1st with the clutch pedal IN, it will randomly cycle through spinning and stopped without any external intervention.

The primary complaint I have is that I have to jerk it into 2nd then 1st to get it into gear about 50% of the time when I'm driving. not impossible but not ideal.

it *feels* like a tranny problem but seems like it could only be caused external to the tranny.

Help.

hah welcome to the club...this happened to me when my clutch wouldn't fully release until i shimmed the PP away, I could slam it into gears, but the rear wheels would spin.....try adjusting the rod on the pedal...make it longer.

Sounds exactly like the clutch is not fully disengaging. Try adjusting the clutch pedal height some more.

lets assume that if i can turn the rear wheels very easily with my hands when the car is in gear and the pedal is in that it does disengage.

Sorry Matt, there's just no way the engine can spin the rear wheels if the clutch were fully disengaged.
Sounds like you have a situation where you have intermittent failure to completely disengage.

could the pilot bearing stick periodically? it's just weird that there would be intermittent drag on the clutch like that.

like why would it stop itself after 5 seconds?

I've seen this on numerous Miatas. It's just a tight tolerance at disengagement. The load is what helps break the friction between the pp and disk.

The clutch pedal doesn't disengage the disk, it disengages the pp - that means the disk is left touching the flywheel and is still stuck on the trans splines. My guess is the friction surface on your disk(s) will eventually wear to the point that this won't happen.

Nothing a few 4K RPM launches won't fix

on some cars dont they use "release springs" to separate the friction surfaces?

I wonder if my shaft isn't lubed enough :cry:

sig material maybe?

Definitely, but if he ever does get his shaft lubed up enough, he still has to deal with this...

Might I suggest some type of prophylactic device?

yeah... sig material... time to replace one y8s quote with another :-)

best suggestion so far.

since you "have to", might as well get someone to shoot it and then post here ;)

AFAIK the clutch disk usually works on the same principal as brake calipers with the pads

http://exmedsupplies.co.uk/acatalog/...med%5B1%5D.jpg

I have the same shit going on over here.

I adjusted the pedal to the max and STILL it doesnt fully disengage, I'm thinking of shimming the slave rod or something.

And I always make the wife lube my shaft, she has experience doing that kinda stuff, wait...What?

I'll figure this out Saturday and report back.

what clutch did you install? matt did you adjust your rod?

I constantly adjust my rod.

srsly tho I readjusted it the other day to Tilton specs. forgot to tighten it though. oops. But it was ok. a little too close to the floor for engagement but considering it was set to the shortest possible length, it worked great. until a block from home. not sure if that was because it was loose or what.

so I lengthened it a little bit but only to remove the excess free play. my top stop was all the way down and I had a mile of free play with full disengagement. I'll test it more tomorrow on the way to work.

Why hasn't anyone said anything about bleeding the clutch, or failing master/slave clutch cylinders?

I also thought the pilot bearing sticking a bit theory sounded plausible.

But I don't know shit.

-Mike