Clutch Master/Slave Cylinder issues (?)

Hi,

I have a problem with the clutch on my truck (4 cyl 4x4). A few months ago I was driving along and went to shift. The clutch pedal stuck to the floor and was slow to return, so I pulled it back up. Everything seemed ok after that, so I figured it was something I could investigate later.

Fast forward 2 months-- I've been on a long trip, and left the truck parked at the inlaws house. They went to move it while I was gone, and the pedal stuck to the floor. They then pulled it up and perhaps tried to push on it again.

Now I am trying to figure out the issue. I am fairly confident that it is an issue with the hydraulic system. Originally I thought that it was the slave cylinder, so I ordered a new one (coming this week). In the mean time I have been poking around under the truck... the state of things confuses me a bit.

The slave cylinder is in the retracted position...i.e it is not engaging the clutch. The master cylinder is fully compressed...and the rod that pushes the piston is slack inside of the body of the cylinder. ( I have not disassembled anything yet). This confuses me, because in my mind, if the master cylinder is compressed, the slave cylinder should be extended, and vice versa. I can not see any evidence of leaks, nor has the level of the brake/clutch fluid changed. I don't understand where the fluid could have gone to allow the master and slave to be in their current positions.

Any thoughts on the culprit? Should I go ahead and order the master as well on monday?

Thanks for any thoughts or input.

 

If there is no leak at the slave, and the level is good in the reservior (not sure if its part of the brake reservior on all, mine is), replace the master cylinder and bleed the system. If the master cylinder bypasses the fluid around the piston, the pedal will stay to the floor thanks to the overcenter spring mechanism on the pedal. It sounds like the piston isn't returning in the MC once you lift the pedal either, probably due to the rubber cup seal folded backwards jamming it up.

 

update:

I removed the slave cylinder and it was extremely corroded on the inside. Basically frozen. I also removed the master, which seemed to be not acting normally. The return spring in the master cylinder did not seem to be working, so I also replaced that. Everything is back to normal, and the clutch feels much better than it did in the last few years, which makes me think that the slave cyl was on it's way out for a while, and not driving the truck for 2 months cemented it's fate.


Thanks for the help.