doing a clutch bleed, but there is no fluid???

[pi5tolpete]

Was starting to find that my clutch pedal was not returning to its full reach while driving. There seemed to be a point where it would hang, and sometimes 'pop' over, but lately not so. Final straw was attempting a leisurely drive on Thursday and I could barely get it into reverse. Thought better of my idea and left the car there.
After exploring here and a few other forums, I was convinced to bleed at the slave cylinder. So I gathered my necessities, 7mm wrench, tubing, etc, up went the car. Reservoir shows max. With the rear left wheel off, you can contort your arm to reach, remove the rubber protector, and get your wrench on, followed by the tubing. So then what? I asked my friend to assist with the coordination of pump the pedal, holding to the floor as I loosened the bleed.
Great.
Only problem, there was absolutely no fluid that came out. We even tried a single to-the-floor-and-hold pedal stroke with the bleed nipple removed but again, nothing!
At this point I am hopeful that it is not internal engine work, and it is only hydraulic.
Looking for some renn-sight to help with next steps.

Peter

[964TargaC2]

Could be that the master cylinder and /or slave is shot, could be that the hose to the slave is shot,

I use a suction bleeder on the slave cylinder..it helps to get things started

[Esel Mann]

I had very similar clutch issues as you describe. I had to go through your pain a couple of years back. I scoured the boards for information and tried to apply that information no dice.

Here's what I stumbled upon when I did the clutch bleed (successfully):

- First, is the bleed screw open enough? What I found is that one travel of the wrench after breaking torque was not enough. It took (I don't recall which) 2-three travels before it was open enough for the passage way to permit fluid to exit. From there I was able to adjust the screw to taste, and operate the screw +/- to permit/block fluid flow out of the slave cylinder. When finished although closed, I had to then re-do the additional turns to then seat the bleed screw.

- Second, I found pedal pumping and gravity techniques did absolutely nothing. And that is despite trying several permutations of the two techniques! It was only when I pulled a vacuum at the bleed screw did I manage to get fluid to travel from the reservoir all the way to the slave cylinder and bleed screw. Once done, I was able to observe pedal pumping and gravity techniques would then work but why do so as I had vacuum assist to help speed up the job time. My conclusion from that was if the system has a boatload of air, neither work until the majority of air is removed by using other forceful means, eg. the vacuum pull.

[Traveller]

Originally Posted by pi5tolpete

Reservoir shows max.

But does the reservoir portion for the clutch fluid have fluid in it?

It really is worth getting a Motive Products Power Bleeder - Model 1109.

[Green993]

Originally Posted by Traveller

But does the reservoir portion for the clutch fluid have fluid in it?

It really is worth getting a Motive Products Power Bleeder - Model 1109.

+1 I have one of these and it makes the job easy. I had your exact problem with nothing coming out. There was crud/corrosion at the nipple. I just added more pressure with the Motive and eventually fluid came out.

[pi5tolpete]

I have a vac assist that I will try and have a motive bleeder on the way from a friend. Will try both.
But how the f-heck is air getting in???

Peter

[Esel Mann]

Remember if you use the motive bleeder or any other bleeder which pushes the fluid from the reservoir side, you need to clamp off the brake fluid overfill line at the reservoir!!!

One possible means is aging of the seals, hoses, and/or hose crimps. How old is the clutch master cylinder, slave cylinder, and slave cylinder line?

[pi5tolpete]

Thank you to all. I'm getting close.

I connected my vac unit and pumped it up. This is AFTER I pinpricked through with the bleed nipple removed to clear the blockage. Once clear, and with some human vac first, the flow started to come. But, it NEVER dropped reservoir level, and when I went to push on the clutch pedal, it flung to the floor. I have sucked out all the fluid between the master and the slave, and when I wiggle the base of the master (the piston end) there is A LOT of play. I mean, it doesn't feel like there is a piston inside the cylinder at all. It is as if the diameter of the shaft is all that is in there, not piston top. So, Me thinks its the master cylinder. Thoughts?

[pi5tolpete]

Does this seem right? Cannot tell what the master shaft should be connected to...


I do realize that I have removed the clip to show the awkward angle achievable my the piston..

[bazar01]

Originally Posted by pi5tolpete

Thank you to all. I'm getting close.

I connected my vac unit and pumped it up. This is AFTER I pinpricked through with the bleed nipple removed to clear the blockage. Once clear, and with some human vac first, the flow started to come. But, it NEVER dropped reservoir level, and when I went to push on the clutch pedal, it flung to the floor. I have sucked out all the fluid between the master and the slave, and when I wiggle the base of the master (the piston end) there is A LOT of play. I mean, it doesn't feel like there is a piston inside the cylinder at all. It is as if the diameter of the shaft is all that is in there, not piston top. So, Me thinks its the master cylinder. Thoughts?

You have to bleed the master cylinder until fluid comes out of the fitting. Then move on to the slave cylinder. Bleeding the master is quite a pain. You have to make sure you catch the fluid and not let it spill on the floor. That was how I did mine after getting frustrated bleeding.

[Green993]

If there is no fluid in the line between master and slave you will get zero pressure and will be able to move the master easily. You will only get resistance when the line is full and bled of air. The master cylinder should be connected to your clutch pedal.

[pi5tolpete]

update:
I borrowed the bleeder from a friend and tried it. EASY AS PIE!
First shot I still had a hanging pedal. Next time I bumped up to 10 psi and bled a bit more. I honestly feel that my reservoir level MUST have been a bit low, I was hearing gurgling, but I cannot imagine that the pickup that comes off the bottom would have a stand pipe that would bring it up past the min level. By the way, what does the >PP< stand for on the clutch side of the reservoir? Will try a drive tomorrow and see.

[Traveller]

Originally Posted by pi5tolpete

I honestly feel that my reservoir level MUST have been a bit low, I was hearing gurgling, but I cannot imagine that the pickup that comes off the bottom would have a stand pipe that would bring it up past the min level.

Although I had my reservoir off the car when I did a complete Clutch Master & Slave Cylinder Replacement during the winter of 2011-2012, I can't recall with 100% certainty as to the internal construction of the reservoir.

I do remember seeing the typical "wall" between the front half and the back half of the reservoir. Internally, the spigots for the brake lines were flush with the bottom of the reservoir.

Originally Posted by pi5tolpete

By the way, what does the >PP< stand for on the clutch side of the reservoir?

My guess: the code for the material used. Another guess: Polypropylene.

There are plenty of clear pics of the whole system for a 993 in the above link.

[Traveller]

Originally Posted by pi5tolpete

Does this seem right? Cannot tell what the master shaft should be connected to...

A pic with a new clutch master cylinder installed...

Originally Posted by pi5tolpete

I do realize that I have removed the clip to show the awkward angle achievable my the piston..

The end of the rod that is within the clutch master cylinder is a ball so that it can pivot while being activated.

[pi5tolpete]

Traveller, thanks for showing just how clean a pedal cluster can looked when compared to mine

I bled again this morning, and with 10psi on the can, I tried the pedal. It returned to normal with exuberance! But with the 10psi off the system, it hung again. So, one more bleed, check, ok, so I buttoned it up. Test drive allows for good shifting with the occasional hanging pedal. I will try the allen bolt adjustment to allow the pedal to 'spring' back a bit more. That spring is confusing, it actually is spring assist for clutch pressure, not spring return for pedal return position, backwards of what I thought it would be for. The spring return is at the tranny.

Car lives for a Mothers Day treat, then to our host for a few parts!

Peter

[Traveller]

Originally Posted by pi5tolpete

That spring is confusing, it actually is spring assist for clutch pressure, not spring return for pedal return position, backwards of what I thought it would be for. The spring return is at the tranny.

Exactly as I understand it.

If your linkages are like on my 993, the clutch pedal travel goes "over center" and gets lighter beyond that point.

If your components are original, you might consider replacing them next winter. They are quite cheap.

[Esel Mann]

Unless there is something wrong with the spring, it will function under all settings. Your current symptoms were exactly mine. I just kept bleeding and finally got tje air out. Be sure to keep the reservoir fluid between max/min. Kinda a pia if you are doing it alone as it takes more time to go back/forth but it is doable. Hang in there you are almost there!

[Rick Lee]

I'm having this problem now. I use a Motive on the MC and a vacuum on the slave, powered by my air compressor. My pedal stuck to the floor and I got plenty of old fluid to come out. I had ATE blue in there and put gold as the new stuff. Once I saw the fluid in the tube run clear, I stopped. Buttoned it all up, went to move the car and pedal clung to the floor. Dammit. I poured out the little bit of new fluid I had left. I have some Prestone DOT 4 that's unopened, but I don't want to do this again. Worse yet, my driver's seat drive cables are frayed, but I never bothered to replace then, since only I drive the car. Now I can't even bleed it the old fashioned way because Mrs. Lee can't reach the pedal with the seat all the way back.

What's the best way to fix this? Use the Motive and vacuum again or the old fashioned way? Doesn't help that my bleeder screw is kind of stripped too.

[jovanybg]

There is a lot procedures written on rennlist, but here is my experience with bleeding the brakes and the clutch slave cylinder:
I am using Schwaben pressure brake bleeder ( 007237SCH01A - 3-Liter European Pressure Brake Bleeder - ES#2774831 ) to connect to the brake fluid reservoir after the old fluid has been pumped out and it is topped off with new brake fluid and pumped to 20-25 psi.
Once I forgot to pinch my overflow line and had a nice, small lake of brake fluid on the ground!!!! Should not forget that in the future!!!
I've started with back right wheel, inner bleeder. 11mm. box wrench does the trick. Open the bleeder and got about 150-200ml. of kind of clean fluid with small black particles. Flushed until only clean fluid goes out.
Repeated the procedure for the back left, front right and front left wheels.
The trick is that the Brake fluid reservoir outlet for the Clutch slave cylinder sits higher than the outlets for the brakes.
Initially I didn't know that and started bleeding the CSC (clutch slave cylinder) with a reservoir full with brake fluid bellow maximum. I've got about 200ml. of blackish fluid out when I've heart "gushing" sound of air introduced to the system. Stop the bleeding right away and looked at the reservoir where I still had about 1/4 full. Clutch pedal dropped to the floor! My heart jumped a few times!!!
Following the advice from the local Porsche mechanic I filled the reservoir all the way past the FULL mark, pressurized it with 24psi. and bleeded the air from the CSC. Flushed out about 50ml. of fluid, depressurized the system, re-filled the reservoir again above the MAX and repeated the procedure with flushing out another 50ml. Repeat again until clear fluid with no air bubbles comes out.
Clutch pedal returned in normal position and a test drive shows better filling when pressing it. I'll repeat it in 2 years.

[gary1101]

If the kinematic clutch pedal lever is worn it can produce a "hanging petal". I had a similar problem that ended up being a combination of a dirty master cylinder due to a torn boot and a bad petal lever. After a rebuild of the petal box and new master cylinder all is smooth as silk.

See pedal for details.