Necessary to bench bleed clutch master cylinder?

[idt512]

Is it absolutely necessary to bench bleed the clutch master cylinder? I just installed a good used master cylinder and im not getting anywhere with bleeding it, the fluid in the reservoir comes back up when the pedal is pressed. Not sure if i have air in the system or a bad master cyl.

Ive bled clutches before but never watched the fluid in the reservoir as the pedal is pressed /depressed... because i never had to.


-Car is a 2g AWD

 

[92AWDHX40]

it seems there is a leak in the system some where, do you see fluid on the firewall, bleed it until the air is out.

 

[idt512]

I already know theres air, ive been trying to bleed it and am not getting anywhere, the fluid in the reservoir just goes up and down as i depress and release the pedal. Even with the bleeder screw open.

 

[dsmcrzy]

I just installed a new cmc this weekend and didn't bench bleed it. I also put in a stainless steel clutch line so mine was full of air and I had no problem bleeding it at all.