Clutch bleeding issues after removing and reinstalling transmission

Hi all! Long time lurker, first time poster. Hoping I can get some sage advice here. Car: 996.1 carrera 2 with 3.4L M96 Background: Removed engine for a different issue (timing chain) and pulled the transmission off to access a timing chain guide screw During reinstallation, I didn't line up the pin on the slave cylinder to the release fork and blew the slave cylinder piston out During this process, I managed to empty the fluid reservoir Besides emptying the reservoir, nothing else was done to the master cylinder, and it was working fine before this I replaced the slave cylinder with a brand new o'reilly version, ensuring the pin was aligned properly Bleeding methods attempted: Motive pressure bleeder, about 1 full gallon pumped through, ensuring the reservoir was completely full to the brim the entire time Tried the porsche recommended method, tried with both the pedal up and down, and the mid-bleeding slow pumping, even tried mid-bleeding fast pumping I tried the motive method with the front end high, the rear end high, and the car level Tried the old fashioned pump up the pressure, hold, and open bleeder screw I was being careful here to close before the end of the slave stroke so as not to let air in Finally tried the reverse bleed with an oil can Tried with pedal up and down Used a transparent hose to ensure no extra air was introduced The swishing sound described below at the master cylinder was still there Current Situation: After bleeding and bleeding, I can't get the clutch to disengage. The pedal is creaking and barely overcomes the helper spring, indicating a lack of return force I tried reinstalling the old sachs slave cylinder and yielded the same result. Much lower return force, and no clutch disengagement When moving the clutch pedal, I can hear swishing of fluid. This might indicate air in the master cylinder? Help needed: I don't want to throw parts at this - is there a way to determine if my slave cylinder is bad before replacing it? Does the swishing sound in the master indicate there is still air? How can I remove the air from the master? With no slave cylinder, I reached my finger in the hole and can move the release arm back and forth a little bit, is this normal? Added photos below - does the pressure plate look normal?

All I can say is that it takes a long time to bleed it manually. The first time I did it after dropping my engine and reinstalling, it took nearly forever�I assumed the slave cylinder was bad so I got a new one. The first evening I actually gave up in frustration - went back the following day and it still took another 45 min to an hour of press clutch, open bleeder, hold pedal to floor close bleeder, release. Repeat probably 30 times. I still don�t know if the original slave was bad but I wasn�t willing to waste anymore time if it was so I just went ahead and replaced it� Good Luck, stick with it

Quotes source post: 18240033

thanks for the reply! Did you hear a similar swishing near the master, or feel a sort of sticky up-stroke? I guess with this encouragement I�ll just keep at it �\_(ツ)_/�

I also blew out the slave due to misalignment. I put the slave back together and pushed the rod in by hand and let it out slowly.....a few times. it was bled. also I once had a similar bleed issue with a new slave on a bmw and used this method and bled it instantly

If you pump the clutch pedal repeatedly does it build up pressure? If so you still have air in the system. If not, you may have nothing BUT air in the system, or possibly a bad master or slave cylinder. If the slave is bad you should see it leaking. If the master is bad it might leak, or it might just be letting pressure back past the seals and into the reservoir. It shouldn't be hard to bleed a clutch hydraulic system. There's hardly anything to it. No way should it take a gallon of fluid. I usually bleed with a catch bottle attached to the bleeder. Makes it a one-person job. I have had situations where I needed to fiddle with opening/closing the bleeder while someone else pumped, but it's rare.

It�s very hard to discern clutch engagement when using a hydraulic clutch. I�m guessing your 996 is off the garage floor so you should be able to start the engine and see if in fact your clutch slave is disengaging the pressure plate. See if you in can row through the gears. When bleeding you want the clutch pedal at the floor. When the air is out of system you�ll need to manually pull the pedal back. This sort of behavior will continue for a little while. You can drive the car and return the pedal with your toe. your pedal will slowly return to normal.

Just did a clutch bleed yesterday on 02 C2, I used a pneumatic vacuum bleeder like the link, suck the fluid thru till fresh fluid is flowing into the bleeder bottle and done. only draw back is also need air compressor, and the plus is one man operation and quick. Amazon Amazon

If you use a pressure bleeder, you can't just let the fluid dribble out. The bleeder needs to be open enough to let a quick spurt of fluid through or you'll never dislodge all the air bubbles.

I assume you bled the brakes too? It is one system. If you did not bleed the brakes too, there will 100% be air in the system. I think you need to bleed the brakes first, then the slave. There is a full procedure on how to bleed the clutch, are you following that? The procedure is available on Renntech, and the Bently. I know you need to have the clutch pedal depressed as you are doing the bleeding, then you pump it back up, and repeat. I forget the entire process, but there is a correct way to do it.

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not really true. The resi has a blocked off internal "tube" and it doesnt matter how or if the brakes r blead. If i had to guess the po is letting the fluid drop too much while bleeding and introducing air. U need to keep the fluid close to full for the entire proccess. Using the pressure bleader really makes this easy but some people only fill the resi and not the bleader bottle. This is a mistake and risks getting air into the system.

Not sure why the Motive pressure bleeder didn't work, but I'd like to recommend a change in the manual method. The best manual method for the clutch is different from the brakes. The reason is because there is relatively little pressure in the clutch line(compared to a brake line) when pressing because of how far the slave is moving. I would propose this: -clutch out -open bleeder -clutch in and hold -close bleeder -clutch out This gives the best chance to push the air towards the bleeder. Otherwise, it will just move back and forth with the motion of the slave. Good luck.

I use: clutch out clutch in and hold open bleeder close bleeder clutch out which uses the pressure plate springs to force the fluid out of the slave. This does not work if there is so much air in the system that the slave won't extend. Then you must use golock911's method.

take the slave off, push the rod in and let it out slowly a few times. leave the pedal up. trust me

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Interesting. I have been wrong for so long. OP, went through my Bentley and found the instructions I printed out when I did it last. Image below. Sorry the image is dirty. Obviously I referenced it....

When I changed my IMSB and got everything back together it took me several attempts using a Motive bleeder to-get the air out of the system. The pedal still didn’t feel right but after driving a couple of days, the pedal got firm and back to normal.

Hey guys! Thanks everyone for your contributions, it's been a busy week as I just got married. I'd like to respond to all the great points raised here, just gonna list them out below: Bad components? (Me) For my sanity, I replaced the master and slave cylinders with good OE replacements I confirmed there are no leaks in the line either Push rod in and let out slowly (Dougn) I see how this could push air backwards towards the master. Quick motion moves the bubble, slow motion backward doesn�t pull the bubble back. I will add this to my to do list Does the clutch pedal create pressure? (Wdb) Yes, and holds it, just not enough to disengage the clutch From this we can conclude there is air in the system (see previous statement about all components replaced) Is the clutch really not disengaging? (Jumpy chunky) It�s really not disengaging Confirmed by trying to drive it Also confirmed on jack stands by stopping one tire with a jack, putting it in gear, and trying to spin the free tire while someone pumps and holds the clutch Try Vacuum bleeder (JohnCA58) I tried pressure bleeder, do you really think vacuum bleeder would make a difference? Open the bleeder screw a lot while pressure bleeding (theprf) Done - I can see bubbles being forced downward through my clear hose attached to the nipple Bleed brakes at the same time (kris Murphy) Not really a relevant point here as discussed in the thread As long as the reservoir is full, the clutch master will be receiving bubble-free fluid through its �no pressure� feeder line The OP is letting fluid level drop (de jeeper) The OP is not letting the fluid level drop (see original post) Method to push clutch in while bleeder is open (golock911, backed up by theprf) This is actually a great idea, it obviously creates an actual flow through the lines to the end instead of the slave just purging itself! It might also create a much more forceful current of flow compared to the pressure bleeder Adding this to my to do list Use the clutch bleeding method from some PDF (kris Murphy) Did this a few times with no luck Again, I really appreciate all the input. This one has been extremely mysterious. I've had a few friends come by and try helping me out all with their own methods and no luck so far.

�Method to push clutch in while bleeder is open (golock911, backed up by theprf) This is actually a great idea, it obviously creates an actual flow through the lines to the end instead of the slave just purging itself! It might also create a much more forceful current of flow compared to the pressure bleeder Adding this to my to do list� ^^^ This^^^ Remember, it takes a long time, but it should work eventually�and make sure you close the bleeder before you pull the pedal back up. Repeat as many times as necessary�

Found the smoking gun. The clutch plate was installed (by me) upside down. Hope someone can learn my lesson! The clutch's center is offset, and you want to have the high part facing away from the flywheel. Otherwise it touches the flywheel bolts and keeps pressure on the pressure plate. See pictures below flywheel bolts that would touch the clutch plate evidence of flywheel bolt contact ​​​​​​​ clear view of offset. left side goes towards flywheel

Uh� yup, that would cause a problem!🤣Glad you figured it out👍

Glad you found it! And thanks for the follow up post�. One thing you can say, you now have the cleanest clutch fluid the car can have.