Hydraulic Clutch Slave Cylinder Keeps Blowing Out

As long as I've had my jeep, which is about 13 or 14 years, at least once a year the slave cylinder on the hydraulic clutch will for some reason over extend to the point that the piston inside the cylinder is pushed out, which of course spills all the fluid out onto the ground and renders my clutch pedal useless.

Any possible idea as to why this happens?

The slave cylinder is cheap...around $30 but it's a pain in the *** to have it do this at random times every year.

 

Is this a factory hydraulic clutch setup or something aftermarket or put together by someone?

 

Over extends? ............put a stop on the travel.
or go back and look at the size of the Clutch master bore volume vs the bore volume of the Slave cylinder.........
is your hydraulic line running near any source of heat?
Slave cylinders like Novaks have a cir-clip in the opposite end..........never seen one come apart and they are rebuildable.

 

This is the stock slave cylinder. The jeep had a 4 cylinder when it was new. I think I read that only the 4 cylinders even had hydraulic clutches. It has an NV4500 Transmission and Advanced Adapters drilled the holes in the bellhousing for the slave cylinder to mount to. Seems like they may have even welded some tabs to the bell housing to receive it. It functions perfectly except for the random times it just over extends. In fact...this latest time it over extended to the point that the clutch fork would not return...the plunger actually got stuck in the "out" position. I had to climb under the jeep and use a pry bar to engage the fork just a little bit so that I could tap on the plunger so that it lined back up and would go back inside the cylinder. Of course it's useless at the point because there's no fluid and obviously not a sealed condition any more.

I don't know how I could put a "stop" on it to restrict how far it would extend but I'll take a look at that.

 

My father and I adapted the 4cyl cj7 hydraulic clutch linkage to our cj5 in 1986 - I think they were girling parts. I wonder if you could extend or create an adjustable pushrod for the slave cylinder or adjust the mounting to get the slave closer to the clutch fork. If you need to buy a new slave perhaps use the old pushrod for parts to extend the new one?