Is there a trick to this. I had to remove my slave cylinder to remove engine and transmission. I had to open bleed vent screw to push back rod to get it out from bellhousing mount. Now after, I cannot get it to pump up enough to even bleed out. Does not seem to pump fluid to slave cylinder. If I have bleed vent open on cylinder and pump clutch pedal should it not push fluid down and out the vent hole on cylinder, and drop the level in the master cylinder? cause it isn't, all I hear is air come out each stroke and my fluid level in master cylinder does not change.

 

Stupid question , but I have seen it many times . You are removing the black rubber insert ,then filling master ? They can be a bear to bleed . Remove cap , remove insert , fill to top and open bleeder . gravity bleed to full level , install cap and pump rapidly! Repete until peddle builds . Let sit for 15 min. And pump again . I have had luck with that method . when properly bled , and full , reinstall insert .

 

Yes gravity bleed to start. Open bleeder screw and hang it over or in a plactic bowl. Leave cap off master so you dont accidentally build a vaccum. Keep topping off til fluid runs clear.

 

I tried to do this gravity bleed but nothing goes through the master cylinder with black rubber cup and cap removed. also tried pumping pedal like this with bleeder open, can hear air coming out bleed vent with each stroke but no fluid goes through, do I have plug or bad master cylinder?

 

Drive the pin out and pull the line out of the master. Then what do you get?

 

Im curious to how this turns out. If you hear air your master should be working unless the plunger is bad and the air you hear is from the master.

I wonder if you didnt push simething back up the line causing a blockage and have the master go bad at the same time or because of it.

 

well I disconnected the line from the master cylinder and no fluid comes out. When I pump the clutch pedal still nothing comes out. I can blow air through the line and out the slave cylinder bleed valve. So I ordered a new master cylinder.

 

Sounds like the piston seal went bad. Glad you figured it out.

 

Your talking about an external slave? Those are notoriously stubborn and there are hundreds of threads on it. What I did was take an old cylinder, remove the bleed screw and drill the center out. Took a two inch piece of brake line and brazed it into the screw. Then threaded it into my slave. Put my vacuum bleeder on and pulled a bottle of fluid through it. Then replaced with original screw. Hope this helps. I also made a compression testing adapter out of an old glow plug by knocking the center out. Brazing a line to it so it would fit my gauge.