Slave cylinder tech?

[Christopher smith]

Anyone with experience with concentric slave cylinders? I have a 1500 pre-crossflow coupled with a Pinto box. There is a concentric slave cylinder to activate the clutch with rather intricate Aeroquip plumbing between the master cylinder, through the slave and off to an external bleeder. The slave gave out and leaked after years but not many miles, and I just installed a new cylinder and master cylinder. I replaced it  with the same model (required engine removal, so quite a job). Now there must be a very small leak in the plumbing. Only a few drops leaking out somewhere inside the bellhousing, but I am getting a soft pedal even after extensive attempts at system bleeding to try to get air out. Can air be sucked into the system on clutch release through a very small improper joint in the intricate plumbing? I understand concentrics are used on a lot of race cars but I must have done something wrong. Ideas?

[MV8]

Fix the leak. I expect that is where part of your pedal stroke is going instead of moving the pressure plate. The pressure is very low compared to brake systems. I bleed them off the car and ensure the bleeder port is on top. I prefer an external slave. Cables are reliable when maintained and provide the most clearance.

 

Non-oem concentric slaves do not normally have a dust seal, so clutch dust and other contamination can shorten the life of the orings.

Oem's usually have a boot also, around a coil spring around the slave to keep the sliding surfaces clean. Because there is a spring, they have a crimp around the end to prevent the assembly from separating when not installed. Over-stroking will break them so the pedal and hydraulic ratios and installation clearances/preload must be correct.

Edited August 24, 2023 by MV8