Master Cylinder?

[Hahnsb2]

I've got a friend with a 91 4.0 5 speed. Yesterday I had to help him on the side of the road fix his clutch. It was out of fluid (the clutch disengagement has never been great in it) so we re-filled it and I bled it and it seemed to work good again till today. Now if you push the clutch in slowly with light pressure on the pedal, the pedal goes to the floor without disengaging the clutch, but if you hit it fast, it disengages the clutch and when I look into the inspection hole, the slave doesn't lose pressure one bit. It's got me thinking it's the MC but I want your thoughts.

 

[HELGA22]

sound like u got a leak somewhere, if know leak got to be the mc

 

[Hahnsb2]

Well it was the MC. It was pretty apparent when we took a closer look and it had been leaking inside the cab so it's changed and works better then it ever has.