Clutch Issues

[Shane]

Well, i got my STi all back together, fired right up and everything so thats good but i have some vibration in my clutch pedal, at first the clutch wouldn't fully disengage so i crawled under the dash and adjusted the pushrod, the further out i adjusted it the more noise/vibration it made at idle, so i adjusted it so it made the least amount of noise and vibration at idle but the engagment point was just off the floor. Soon as you start the push the clutch in you can really feel the vibration in the pedal but once its all the way to the floor it completely goes away... Pedal also doesn't feel as stiff as i remember, it has been awhile however, it also doesn't feel like the pedal comes back up smoothly, like it almost wants to stay to the floor but snaps back up. I don't know too much about this stuff so im kinda stumped as to what the vibration is coming from. Looking for any tips or advice.

Thanks guys!!!!!

[ZXTUNER]

disk may be off a hair.is it a stocker

[Shane]

How can the disk be off tho? The shaft goes threw it and centers in the pilot bearing?? I had thought that maybe the PP was just a bit off because the alignment pins that Automotive suply put back in after they reserfaced it did not perfectly match up to my PP holes, i was still able to get it on but some other people pretty much said i was dumb for thinking something wasn't aligned perfectly... No, its not stock, Spec Stage 2+

[Dizmm]

I'd guess the pressure plate. Did you have the flywheel resurfaced?

[Shane]

yup Automotive suply did it. I just don't get what would cause the pulsating/vibration that would come back threw the slave to the master to my pedal.... I just want to get it figured out before i take it all apart again.

[Dizmm]

the pressure plate acts as a spring. when you press the clutch pedal, you are pressing in the "spring" of the pressure plate.

[ZXTUNER]

ment to say pp dont know why i typed disk. would make sense if the pins are a little off

[Shane]

I just don't get why it doesn't feel as stiff as it used to, I remember that thing being stupid stiff! Wouldn't imagine that it would go bad when it was just sitting around... hmmm

[Deadly_Evolution]

I'd also say you should check to make sure the flywheel and pressure plate look true when the engine is turning over. If they are not seating right, it will throw it out of balance at certain RPMS.

Bent diaphragm fingers will also cause this issue.

[Dizmm]

Do subaru's have a step to the flywheel or is it completely flat?

[Deadly_Evolution]

STi should be stepped.

[Shane]

It has little "fingers" that come up off the flywheel where the PP bolts up

[Dizmm]

if that step is off, you will have clutch issues. I would hope the shop that did the resurface job checked the step for an 05 STi.

[Shane]

Yea I'm not sure, they cut the whole thing down the same. I just wonder if the PP is out of alignment Just a touch or something like that.. everything was in good shape when I put it in, no bent fingers new bearings all that jazz

[Dizmm]

Yea I'm not sure, they cut the whole thing down the same. I just wonder if the PP is out of alignment Just a touch or something like that.. everything was in good shape when I put it in, no bent fingers new bearings all that jazz

make sure the pressure plate is sitting completely flush with the flywheel. maybe the dowel pins are not getting pushed in through the holes on the pressure plate. You should be able to see this through the dust cover.

[SgtRauksauff]

are you 100% absitively posolutely sure that the step was machined properly?

what did you mean by the pins were off a little bit?

When I got the flywheel for my corolla, the pins weren't actually pushed in all the way properly, I had to actually take the flywheel back off and tap the pins in.

here's a pic of it, the pin on the right is not flush, and because the pin has a shoulder, it kept the PP from sitting flush on the step of the flywheel.
http://sharkpork.com/gallery/d/2120-2/ppNotFlush.JPG

--sarge

[Deadly_Evolution]

How did the crank look in the new engine? Where there ANY marks or dings on the flywheel bolt hub? Those mating surfaces must be nearly perfect, any defects there will amplify greatly as the diameter of the flywheel gets larger. I know the machining specs for how a true a flywheel must be is like .0004" from side to side. To give you an idea how flat that is.. the thickness of a piece of note pad paper about is 8x greater!

[Deadly_Evolution]

are you 100% absitively posolutely sure that the step was machined properly?

what did you mean by the pins were off a little bit?

When I got the flywheel for my corolla, the pins weren't actually pushed in all the way properly, I had to actually take the flywheel back off and tap the pins in.

here's a pic of it, the pin on the right is not flush, and because the pin has a shoulder, it kept the PP from sitting flush on the step of the flywheel.
http://sharkpork.com/gallery/d/2120-2/ppNotFlush.JPG

--sarge

Yes this.. is something you NEED to look at.. good picture sarge! That tiny amount will throw your flywheel totally out of balance and cause extreme vibrations.

[SgtRauksauff]

here's a close-up of that same pin, after I took the PP off:

before:
http://sharkpork.com/gallery/d/2208-2/P1000797.JPG

and after I tapped it in all the way. (the opening is slightly chamfered, so it looks like the shoulder of the pin might be above the flywheel surface, but it is flush, as measured by a straightedge.
http://sharkpork.com/gallery/d/2203-2/P1000796.JPG

--sarge

[Shane]

Hmmm ill have to take a look at that. Just got laid off so might just be selling it. We shall see I guess....

[EVILUTION]

Sorry to hear that man.

[SgtRauksauff]

that sucks, good luck!

[Shane]

Yea it does suck but at least now I have plenty of time to work on my car and maybe ill actually make it to a TT for once

[KARKRAFT]

Yea it does suck but at least now I have plenty of time to work on my car and maybe ill actually make it to a TT for once

Hope you find something soon. That said, I spent most of 09 laid off. It sucked up all my savings, but that was the best summer I've had since high school.

[Mr. Fuji]

Its possable that the Throw Out Bearing has not engaged the clips on the Pressure Plate. The throw out bearing "Pulls" The fingers on the P Plate away from the motor. It doesnt "push" the fingers on the pressure plate closer to the motor as in most clutches.
When you removed the motor, you needed to remove the blind plug on the bell housing, then slide out the clutch fork pivit rod by thredding in a bolt (6mm if I remember correctly) into the end of the rod before removing the motor. That lets you pull the fork come off the throw out bearing so you dont mess the fork up or the throw out bearing.


AhhhhSoooo

Mr. Fuji

[Shane]

Yea I did all of that, I can see the TOB pulling on the PP it disengages everything just has vibration. Gotta tear into it and take a look. Been busy roofing the past couple days