jbrob007

PO had the entire clutch system changed in 2009 - approx 30K miles ago. I've adjusted the intermediate plate a couple of times using various techniques posted on here... I've powerbleed the clutch system under pressure until all the old fluid was changed, includind unbolting the slave & holding the bleeder valve higher than the slave to get out ALL the air. We had clear fluid with no signs of air bubbles by the time we were done. I measured the slave piston travel with the pedal to the floor - between 15 - 20 mm of travel. The throwout bearing squeaks when the clutch is disengaged, but shows no signs of failure (not throwing grease, etc). Took the car down to test it and the clutch is STILL chattering & not releasing fully... BUMMER We can feel it with the rear wheels in the air and the car in gear with the clutch pedal to the floor...

Anybody know the proper slave piston travel per the WSM?

Also, anybody know the proper technique to adjust the intermediate plate?

mark kibort

if you can put the clutch in and get the gear lever from neutral to first or reverse, the intermediate plate is adjusted. especially if the drive shaft is not spinning. this happens when you have a 1mm gap at the H adjusters. this gives the clutch some movement to release off the flywheel, but not go too far and hit the pressure plate. thats why its 1mm gap. i rivet min there and have been racing it that way for 2 years now, and its absolutely perfect.it will never be a problem until the discs wear down to min values, which ive never seen.
(usually a throwout bearing or pressure plate fails before that happens.

as far as the release and chattering, thats another issue. usually the dual disc clutchs have a funky sound and feel even when working well.

Mk

Ducman82

his shift almost has a "ratchet" feel to it. when going in to any gear (car not moving clutch in) you get a double click. like as if it was Neutral, Half first, First etc. really odd....

Landseer

Lever intermediate plate adjustment all the way backward.

More importantly, make sure the master cylinder plunger apparatus has been modified per the Rob post.

Should do it.

Mrmerlin

I would inspect the MC piston remove it and post a picture of what you find.
There is a good chance that your MC has been changed,
if so the new part wasnt made to the same spec as the old part,
thus the piston is too long so you wont get a fully releasing clutch.
Posting a picture of what you have will reveal the truth

jbrob007

It does have a new MC - replaced in 2009 along with the slave, inter plate, pressure plate, both discs & throw out bearing... Sucks that the NEW MC doesnt meet spec... WTH?

I havent a clue how to remove the MC and inspect the piston. But, I can read up on it and figure it out... eventually. Per the Rob post? Anybody got a thread name or link? In the meantime, I'll keep searching the forum...

Thanks!

Mrmerlin

its not too hard to do,
first put a piece of saran wrap over the MC res put the cap on.
Remove the DS parcel tray,
get a few rags,
remove the floor carpets.
Slide the seat all the way back.
Under the dash,remove the clip on the clutch rod pin and slide the pin out so the clevis releases the pedal.
remove the bellows and remove the pushrod.
take a long phillips screwdriver put it into the MC and then with the other hand release the C clip let the parts slide out put your rags under the MC to catch the fluid.
remove the piston and post a picture .
TO FIX it, you will have to remove about 4.5 MM of the tip then also cut off about 2 winds of the spring so it wont go into coil bind and fracture.
put a slot in the end of the piston.
Once this is done refit the spring and piston to the MC have a helper remove the saran wrap and while the fluid drains into the MC slide the piston out enough to remove the air,
once there are no more bubbles fit the piston in and refit the c clip.

' NOTE you should also check the routing of the feed line to the MC as sometimes it gets routed with a loop and this will trap air you want it to be in a continuous rise to the feed port

jbrob007

Merlin, Which end of the spring do you cut off the 2 winds? Also, will a dremel with cutting blade be sufficient to trim off the 4.5 mm of piston? A simple but important question I think even a noob-mechanic like myself can do this relatively well. I'll report back on the results.

Thanks again!!

Mrmerlin

post a picture of the spring and the piston we can go from there

Lizard928

NEVER DO THIS, it doesn't work on 99% of cars, esp when the clutch discs are new!

MK says 1mm which is about .039" In my testing .020" was suffice for full release of forward disc. With the clutch engaged (clamping), put a .020" feeler gauge under the H adjuster and push it forward onto the gauge. Do this for all 3 adjusters. Then lever the release arm backwards, you will see the int plate move backwards, and give JUST enough room for the clutch disc to free spin. Then the little movement more allows the rear to spin freely too.

With doing this, and properly working hydraulics (no air, good flex hose, no leaking seals), there is no need to cut the 4.5mm off the end of the clutch MC piston. I have installed numerous like this and they NEVER come back. I have a couple with the porken clutch stop and the pedal doesnt even come close to hitting the bottom of the piston even with the full length.

Mike Frye

Disagree Mark. Mine is smooth as silk since the replacement of all clutch parts back in '07 or '08. The trans is inherently not as smooth as a modern car or as quick to shift by it's very nature, but I don't think there should be any 'funky sound and feel' in the dual disc clutch operation.

Joel,

I would take Stan's (MrMerlin's) advice.

Some guys on here found out a few years ago that the length of the rod on the slaves at least was changed for some reason. I think the MC rod may have been changed too. It might be that the new combo works together, but I don't think either one is interchangeable with their predecessor with no other changes (if you know what I mean).

jbrob007

Guys, I've adjusted the intermediate plate 3 times. The last time I used the .020" procedure and it looks to be adjusted as well as its gonna get. It has to be the hydraulics or the tranny - most likely the hydraulics. All the hydraulics are new in 2009 with the exception of the clutch slave flex hose which I replaced recently. We've bled the entire system with a powerbleeder - do I still need to bleed the MC seperately? If not, then the only thing left is the PO's car shop used the wrong or at least different MC & Slave with different length pistons/push rods, etc... I've always had shifting issues and I've recently discovered that its the clutch not releasing fully. With the installation of the Lizard Shifter it has magnified the effects immensely.

With the clutch pedal rod properly adjusted, the MC bottoms out three inches from the carpet (doesnt come anywhere close to the PKlutch stop). Makes sense to me that I'm not getting adequate pressure to move the Slave piston enough to fully disengage the clutch. I'm gonna pull the MC guts today and see whats what... If its got the later / longer piston, will it hurt anything to trim off 4.5 mm & 2 winds of the spring?

Mrmerlin

no it wont hurt anything.. you will just have more travel in the MC bore.

The only caveat is that if you cut off too much of the tip then the rear seal will pass the feed port and case a leak to the end of the piston.

Colin I have tried what you have posted and found that the clutch just wont release enough to work well, it will either grind in reverse or first ,
the extra amount of push available from a longer stroked MC makes a difference, if you were to see the old VS new pistons you might be shaking your head.

The other critical part is to reduce the spring length I have seen more than a few of the MC that had shattered springs the pieces went into the slave and quickly cut the seals

Lizard928

Stan,

I've seen both old and new mc, and I'm not saying don't cut the end off. It causes no harm. All I'm saying is that I've not needed to myself.

mark kibort

absolutely DO NOT LEVER the H adjusters all the way back 90% of the time (and there are some anomonlies that folks like Landseer have seen where that CaN work, but no gurantees) dont do it, as it WILL now allow for the discs to be alowed to spring rear ward and make contact with the pressure plate surface, thus spinning the drive shaft with only a tiny bit of contact friction nessarary to spin it up.. this will make it IMPOSSIBLE to shift from neutral to a gear, unless the sychros can provide the friction to slow the shaft down.

again, this is STUPID to advise. Ive adjusted too many of them to NOT warn you to not use this techique. agian, it might work if you are lucky, but do the adjustment as the factory has suggested. 1mm of gap. just enough to release pressure on the flywheel from the clutch discs., but not too much where they tough the rear ward pressure plate surface. this is FACT and cant be argued.