1991 Cherokee, 4.0 Inline 6, AX15 Manual transmission with internal slave cylinder. I have replaced the clutch, pressure plate, pilot bearing, slave cylinder, and the master cylinder. Still, when I bleed the clutch and attempt to drive I get maybe 100 yards before my pedal goes completely soft again. Even when I bleed it it never gets completely firm. I have tried every method of bleeding it known to man, so I doubt that is the issue. I am at my wits end at this point. Is there maybe a vacuum line somewhere that I am missing, did I incorrectly install the slave? Anything helps.


Note: The master cylinder stays full of fluid, and I do not see any obvious leaks.

 

Seems to me the only thing that could be happening is the fluid is leaking past the master cylinder piston back into the reservoir. The cylinder could be dried out depending on how long it was on the shelf.

 

The problem was persistent before and after the master cylinder swap.

I did slave cylinder, clutch, and pressure plate all first. Once I test drove it and discovered the soft pedal, I swapped the master cylinder.

 

Been almost a year. Any update on this? What was the cause, and how did you resolve it?