ZF clutch master cylinder

[rede30]

I am having trouble with my ZF clutch master cylinder. How to you bleed these suckers? the pedal is very soft and i pop out of gear a lot. I have been puping away and nothign flows threw the unit. Any tricks you guys know? I also closed the valve and had a friend pump a lot and no real pressure built up. Do i just do this a ton?

[LINUS]

You have a bleed screw on it just like your brake calipers. Need more info (recent swap, new slave cylinder, physically is your hydraulic line in good shape, etc.), otherwise we are all guessing.

[rede30]

I have been treating it just like a caliper and yes i have been using the bleed screw. My line is brand new, the slave is old but it worked before this swap. The car sat for about a year and a half and has about 10 miles on the s50 swap. The clutch seems to grab really well so there is no slipping.

[matt]

Try taking it out and holding it compressed (rod pushed in with a c-clamp) and bleeding it that way, then put it back in and see if it's better.

[surebimmer]

I pulled mine off the transmission and pushed the rod in all the way then opened the bleeder screw fluid/air comes out. Closed bleeder screw before releasing rod. Repeat untill no air comes out.

[So Live]

HMmmmmmm i got mine bled pretty well with out compressing it but its not 100% maybe ill have to try taking itout and compressing it. Thanks for the tip!

[LINUS]

Are you pulling the fluid through under vacuum, or pushing from the brake cylinder when bleeding? - May not solve anything, just wondering really. I'm bleeding my whole system tomorrow as a fresh buildup (dry right now), sort of wondering what I'm in for now too.

I've got it pretty easy since I just have one of those deals you hook up to compressed air and it pulls fluid under vacuum. Love that thing. Makes oil changes a dream just shoving that rod down the dipstick tube.

[grib]

I used a vacuum bleeder on mine with a helper pumping the clutch. It still took at least 10 cycles of pumping/bleeding before the clutch felt solid, and I'm still not sure it's 100%.

Be certain while you're bleeding that the clutch intake (blue/braided line going into the reservoir) has fluid to draw from or you're just sucking in air. The reservoir will need to be above full and the car tipped forward to best results.

It's a PITA to lay under the car and bleed that thing, but keep at it.