How do i drain hydraulic clutch cylinder?

[KILLANOLA]

How do i drain hydraulic clutch cylinder? (or is called a slave or clutch cylinder?)

 

2 days ago i went to go into my 1995 nissian pathfinder and the clutch was all the way down to the floor and had no pressure on it and there was no fluid in spot where fluid goes in.

 

I put clutch fluid in the spot where it goes in and it is still holding fluid but there is no pressure on the clutch at all and the car wont go in gear.

 

As you can tell I'm a novice at cars any help would be nice

 

Thanks

[ahardb0dy]

you mean how to bleed the salve cylinder? there is a bleed screw on it

[Slartibartfast]

Sounds like there's a leak somewhere. The reason it's got no pressure now is that there's air in the line or in the master cylinder piston. Brake fluid isn't compressible, air is, so you push the pedal down and the air compresses instead of pushing the clutch out. You have to bleed the air out of the system to get it to work again. Instructions should be in the service manual, MT section.

 

The old fluid must've gone somewhere, so try and track down where it went. It might help to have someone else to watch the cylinder and whatnot as you try to bleed air out/fluid in. That's how I found the leak in my brake system; it was oozing out the side of the master cylinder, but only when I had my foot on the brakes, so one person wouldn't have found it. IIRC there should be a little hole in the bell housing meant to let condensation and whatever out from around the clutch, so you might take a look at that as well and see if there's clutch fluid around there (indicating that the slave cylinder's leaking).

[gv280z]

Boy this brings back memories, A very long time ago I replaced a slave cylinder and bled atleast twice. It's easy to do by yourself if you've got a bleeder tool, you can get from an auto parts store, they're not expensive. It looks like a large plastic tube with a hose coming off of it and a "squeeze arm" on the back to suck the fluid out while not allowing air to flow back into the line.

 

Or you and a buddy can do it, one person sits in the car and pushes the clutch petal down while the person underneath has the valve open, this will push the air and fluid out which you will need a drain pan to catch. Close the valve, announce to the petal guy it's closed so that he can bring the pedal back up, if the valve is open when you do this you'll only succeed in sucking air back into the line again, so: Petal goes down while the valve is open to bleed the line, close the valve, petal goes back up. Repeat process until only fluid is coming out and petal guy reports there is proper feedback / pressure in the clutch petal.

 

Needless to say this job requires an outstanding level of communication. Good luck!

[Slartibartfast]

^ And top up the fluid periodically while you're doing that, or you'll suck air into the master cylinder and get to do it all over again.