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Discussion Starter #1
well this is embarrassing....in my garage (away from home and my laptop) right now after finishing up a brake fluid flush (motive power bleeder-->RR, LR, RF, LF, clutch bleed screw) and I go to get in the car and the clutch pedal, with no resistance drops immediately to the clutchstop. I remember this happening before on my e36 m3 but I remember it gaining back resistance after several strokes with some time. what did I/am I doing wrong and/or what do I need to do? thanks!
 

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You probably let air into the clutch hydraulic system. The solution is to bleed the clutch slave cylinder.
 

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I would bleed the clutch again, if that does not help, the master or slave cylinder decided they were done working, need to order a new one.
 

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Discussion Starter #4
yup-air in the clutch line...no idea how it got in there-thought my technique was flawless. thanks fellas
 

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Did you remember to put the cap back on the master cylinder?
 

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Discussion Starter #6
yeah (assuming you mean the fluid reservoir attached to the master cylinder), but i don't see how that would introduce air into the system. the brake fluid reservoir is either at the minimum level, or not, regardless of the cap being on or not. at least that's how understand the system...?
 

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Is the car sitting level?

Do you have the clutch cylinder removed and the piston compressed?

The clutch cylinder has a separate "chamber" at the back of the brake reservoir. It is all one container, but there is a baffle that separates the two. The fluid flows over the baffle to keep the clutch cylinder full of fluid. If your level is low and your front wheels are in the air, it is very easy to allow air into the system. Ask me how I know......
 
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Discussion Starter #9
The clutch cylinder has a separate "chamber" at the back of the brake reservoir. It is all one container, but there is a baffle that separates the two. The fluid flows over the baffle to keep the clutch cylinder full of fluid. If your level is low and your front wheels are in the air, it is very easy to allow air into the system. Ask me how I know......
ah hah! i think that is it. i thought there was something "funny" going on when check the levels in the reservoir, periodically. why in the world is there a partition? i guess there's some explanation for it. i guess you really need to keep the level close to max when bleeding your clutch, too.
 

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Absolutely, you have to keep a very close watch on it. Hope things work out my friend.
 

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I think the baffle is there so that if you lost the line (and all the fluid) to the clutch, you'd still have brakes. And yes, that reservoir is much smaller.
 

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Clutch bleeding help

I just recently finished replacing my brake booster + master cylinder. Booster was flooded with water from the last storm here. I bleed the brakes okay using the 2-man job; pumping the brakes while opening the bleeder screw. (RR, LR, RF, LF) I tried bleeding the clutch line using the same 2-man jab but it just would not work. The clutch pedal just drops down to the floor.

Now I have searched here and found that others use motive power bleeder. Also, others remove the clutch slave and compress the rod to bleed the line.

My question is do I need the power bleeder AND remove the clutch slave to compress the rod? Or can I just get to a power bleeder and bleed the clutch line without removing the clutch slave?

All I have now is a puny hand vacuum pump and it sucks donkey balls. :Thumbdown: Might get myself a motive power bleeder. Thank you.
 

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I didn't use a power bleeder and I was able to bleed the clutch fine with 2 people. You probably have air in the system. Are you filling th MC high enough to spill over into the clutch chamber?
 

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Discussion Starter #15
My question is do I need the power bleeder AND remove the clutch slave to compress the rod? Or can I just get to a power bleeder and bleed the clutch line without removing the clutch slave?

All I have now is a puny hand vacuum pump and it sucks donkey balls. :Thumbdown: Might get myself a motive power bleeder. Thank you.

i think the deciding factor in what you need/should do as far as thoroughness, here, is that you are not simply doing a flush on an intact system but that you have replaced major components in the system. not sure if you NEED a power bleeder--although it would make things easier and quicker, i would think--but, and i think others would agree, you SHOULD manually bleed the slave cylinder. good luck!
 

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If you've changed the brake master cylinder or introduced air into the brake system, you need to get a dealer to bleed it properly - it needs to be hooked up to the computer to properly bleed it.

If you're just bleeding the clutch, I've always managed to do it just by gravity or power bleeder with everything still intact.

Nick
 

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The pick up line for the clutch fluid is way higher in the reservoir.
So if you do not keep the level high enough,you introduce loads of air.
 

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I just installed a new clutch, new slave cylinder, new clutch line, I have the plunger on the slave depressed and I'm using a Motive power bleeder. The reservoir is full before hooking up the bleeder but nothing will come out of the slave cylinder but some air if I move the clutch pedal which goes to the floor. The master cylinder isn't leaking fluid. What should I try to bleed this line?
 

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I just installed a new clutch, new slave cylinder, new clutch line, I have the plunger on the slave depressed and I'm using a Motive power bleeder. The reservoir is full before hooking up the bleeder but nothing will come out of the slave cylinder but some air if I move the clutch pedal which goes to the floor. The master cylinder isn't leaking fluid. What should I try to bleed this line?
What should happen is the bleeder pressurizes the reservoir, which forces fluid down to the clutch master cylinder which, if the pedal is fully up and the bypass port is exposed, allows fluid and trapped air to flow continuously through the bypass port to the slave cylinder and out of the open bleed valve.

Since you don't have a continuous flow coming out of the bleed valve with the bleeder pressurized, maybe:
- the bleeder is pressurized but the tubing from the bleeder to the m/c reservoir is plugged (or there is a closed valve in it?), or the small bypass port in the clutch m/c is plugged,
- the piston in the new clutch m/c is not back far enough to expose the bypass valve. Like the wrong m/c, the pedal movement restricted (can't come up enough), or the rod in new m/c too long (is it adjustable?),
- you've got the slave cylinder rod so far depressed into the cylinder, the inlet port is plugged by the piston. Try backing the rod off a bit (unlikely, now I think of it since you are getting a puff of air out the bleed valve when you push the pedal down)

In short, if you don't have brake fluid or air pissing out of that open bleed valve on the slave, something is plugged.
 
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