Clutch WILL NOT Bleed

[JGood]

I've bled my clutch every fuckin way possible. Pressure, gravity, ruining-my-arm-from-pumping-for-45-minutes, bench bleeding, everything. This fucking POS is still spongy. New Sachs clutch kit. New slave. New stainless hose. Master is not leaking.

What the fuck is wrong with this thing? I started throwing shit because I just wasted another 2 quarts of ATE Super Blue trying to bleed this thing before I go to the track on Sunday, and now I'm shit out of fluid and my clutch feels even worse then before. So I came inside so I don't break anything.

The fucking thing takes twice as long to return to resting position as it should. By the time I get back on the gas it's only half way up, and I'm just free revving until it engages.

Who wants a free 325is? I fucking hate this car right now.

[NC325iC]

are you getting fluid to come out? is it a new slave or is it old? i did mine with vacuum bleeding, which sucks btw- no pun intended

[JGood]

are you getting fluid to come out? is it a new slave or is it old? i did mine with vacuum bleeding, which sucks btw- no pun intended

yeah it'll bleed fine... fluid comes out, some air bubbles, eventually the bubbles stop. Keep doing it for safe measure, close it up, and I'm still stepping on a scotch pad when I try to step on the clutch pedal. It's a new slave. I've tried 2 new ones, actually. I've done this before, and know how the process works - but something is fucking up, and I'm overlooking it.

[BDSax]

you might have to take the slave out and flip it upside down. an air bubble gets stuck and doesnt come ot all the way, you will just keep getting kittle bubbles.
On my m535i i took it out and used a pressure bleeder and it worked like a charm. on my e30 i was a dumbass and bled it by pumping, took the slave out and held the pin in. it didnt pop out but it really hurt my hand.

[jlevie]

This could well be a bad master cylinder. I'd replace it even though you can see any leakage.

[JGood]

I just installed a new master and slave a few hours ago, again. Same fucking shit. Not a single change in what it does. Spongy, and releases slow. I took the slave out to bleed the system, compressed it a few times by hand. No more air is coming out.

I'm fucking pissed. I don't even want to own this pile of shit anymore.

[jlevie]

With a new master and slave the only possibles left are the clutch itself, or the lines. A slow to return pedal could be a restriction in a line that comes into play as the pedal comes up.

[LINUS]

I read somewhere if you have a ton of problems to ziptie the slave piston in, then bleed, BD mentioned that though. I was under the impression that was the be all, end all cure for bleeding a fresh system. Guess not, since it sounds like you have solid components everywhere else.

[Mike B.]

Let's walk this back, why did you remove the master/slave in the first place?

[gazellebeigem3]

I got a serious air pocket out of my clutch line but taking off the reservoir cap and pushing the slave down very slowly.

[JGood]

OK, I'll start from the beginning. Bought the car, but broke the guibo on the test drive. Driveshaft actually broke free from the front bushing and hit the transmission mounting ear and broke that, and broke the shifter. Anyhow, I put a known good trans and driveshaft in, new slave, new sachs clutch kit, new guibo, CSB, blah blah blah. It was spongy after I bled it, but not real bad, still perfectly drivable. Did track days, autox's, daily driving, everything.

This weekend I had some free time and figured I'd get rid of this slight spongy-ness and install a stainless line while I was at it. Did this. Still spongy, and now it has the slow return. So I replaced the master and slave cylinders. Bled the system, still slightly spongy and slow to return - feels exactly the way it did before. Not real slow, but slower then it should be and fast shifts are no longer possible.

Would an air pocket cause slow pedal return?

Could the clutch itself cause an issue (like broken pressure plate tabs)?

[jlevie]

A slow return of the pedal could be caused by anything that is restricting fluid flow from the slave to the master or from the master to the reservoir. And I'd want to rule that out before dropping the transmission.

At this point I think I'd dismount the slave, clamp it shut, and see what the pedal feels like. That eliminates the clutch completely. Next I'd gently extend the slave (don't let it pop apart) and see how hard it is to push the piston back in. If it is very difficult to compress the slave I'd start replacing lines.

[browntown]

check for a kink in the hard line from the master to the point where the flex line to the slave starts. I twisted one on accident and put a kink in it. Had to re hard line that connection.

[JGood]

The metal line is not kinked and the stainless line is, well, stainless and brand new. Maybe something is inside of it? Should have just kept the old beat up rubber line.

When I was bleeding I found it hard to push the slave rod back in by hand when I had it removed from the trans. Not sure how hard it should be to push in, but it definitely didn't just push right.

So how do I explain the spongy-ness that has been present since I first did the clutch months ago, and have since replaced/bled everything multiple times?

[JGood]

Solved. Kind of.

Stainless slave cylinder hose must have something inside of it. I can blow through one end but not the other, so it must be getting caught int he 90 degree bend near the slave end.

Put the old line back on, pedal springs up as quick as it should. Still spongy as it has been for months, and now it has a 1" or so dead spot at the beginning when you first push in the pedal. I'm not concerned, my 325e has been like that for ~4 years since I did a five speed swap.