I have a strange thing occuring. Cluch fluid is leaking from around the cap on the master cylinder in the area of the little round center piece on top of the clutch master cylinder cap. I hope that was clear but I also need to tell you that I replaced the clutch master cylinder cap and the new cap is doing the same thing. Any ideas? maybe air in the lines 93 Toyota X-cab 4x4 V6 Thanks

This may seem to obvious, but what about the fluid level? If the fluid level is too high, this cound possiblly be a result.

One thing you could try is to look at the fluid with the cap off while someone actuates the clutch. Notice when the cluch pedal is released if fluid shoots up, or small bubbles appear. Either could be a sign of air in the system.

Are you familar with bleeding hydraulic systems?

I have not bleed the clutch before but have done the brakes many times. I know where the bleeder screw is on the slave and so with some help I could probably do it , thanks

Having just spent the last couple of days trying to bleed a stubborn clutch line let me share what finally worked for me, and what will be my procedure should I have to do this again in the future.

For whatever reason the clutch would not bleed using gravity, vacuum, or pumping the pedal. I finally tried attaching a vinyl hose to the bleeder and routing it up approximately 3" before dropping it down into a container to catch the expelled fluid. I then applied 5psi of air pressure into the vent hole of the clutch master cylinder. This forced the air and old fluid out of the bleeder and created a 3" section of tubing filled with fluid; sort of like the P trap in your sink drain. This eliminated the possiblity of any air getting back into the slave cylinder. It took me a couple days to come up with this idea, mostly because I was too pissed off that I couldn't get the darned clutch to bleed out to see the obvious solution. Once I did this though it only took 5 minutes to completely bleed the system and have new fresh fluid throughout. This system also allows for doing the job with only one person. Hopefully this will help someone else avoid the same frustration. <img src="/forums/images/graemlins/notooth.gif" alt="" />

This might seem obvious but is the vent the smaller round circle on the cap. If so this is where the fluid on my truck is leaking and yes maybe I did fill it to much

(If you clutch is actually working okay, you prolly don't need to bleed it) But if not, it's basically the same concept as bleeding brakes. Of course you will need an assistant to pump the clutch pedal. Be sure to keep enough fluid in the master cylinder. If the fluid level is low and the pedal is pressed, you will have air in the system and be right back where you started.

One thing I am still puzzled by is why it's leaking from this part of the cap? I know in my master cylinder (92 P/U) there is a plastic floater that floats on top of the fluid. But I'm not sure what purpose it serves.

Did you see what happens with the fluid when the clutch is pressed and released with the cap off?

No I have not seen the master cylinder with the clutch depressed. On my next days off I will do some more work on this