Master/ Slave Question.
 

Well i have a little leak coming from the slave, and am curious how hard/ steps to changing it? Never changed one before on any car. Also i had a new slave put in in 08 when i got a rebuild, so then is it really true that you need to change the master while doing the slave? it seems the master is out lived the slave twice now...

The slave cylinder is really the work horse of the system. Its internals are smaller than the master, and sees the direct feedback from the pressure plate. You can replace both if you like as you will have to re-bleed the system when replacing either one.

Changing it is relatively easy.

- Jack up the front end
- Remove the starter to gain access
- The slave resides on the upper drivers side of the transmission
- Remove the 10mm fluid line fitting (I recommend a clasp wrench to keep from stripping the fitting.)
- Remove the two 12mm bolts holding the slave.
- Grease the rod end of the new slave with lithium grease for smoother operation
- Replace slave with new one (I recommend an OEM. The rod fits better in the clutch fork pocket. I have had issues with "parts store" slaves slipping out.)
- Reassemble & bleed the system

I do recommend replacing the old rubber line with a new OEM, or a braided line. The 10mm fitting can be hard to get to from the bottom, so removing and re-attaching it from the engine bay fitting can be a little easier. Use PB Blast on the fitting and let it soak for a bit.

thanks for that, i actually have the new oem slave here waiting to be put in, and already did the braided line. what did you mean grease the rod end?

Sorry for thread jack but its related. Other than leaking how do you determine a slave is bad. I made the mistake of doing a engine pull at night and it was hung up on something. Came to find my slave was still connected. The metal hard line was bending a bit but not sure on slave itself.

You'll want to add some grease to the rod ball of the slave cylinder. The ball sits in the pocket of the clutch fork just inside the transmission. This grease will help eliminate squeeking from the metal to metal contact.

The slave is likely fine if you just bent the metal line. They fail from wear. The internal seals eventually allow fluid past them reducing pressure in the system when the pedal is pressed. The OEM lines are pretty inexpensive from Mazda, so I recommend replacing if they get mangled or the fittings get rounded off.

When the slave or master is failing, the system won't hold pressure or it will hold it intermittently. Leaking externally can be a sign, but it can also leak internally without showing fluid.

You can change just the lines? even the hardline that comes out of the slave itself? Does a braid replace the hard and soft lines? The piston/ball just seems like it may be sticking out to far? Is that possible? I can even move it side to side. Cant remember how it was before this incident.

FYI.....

There is NO need to remove the starter. This can be done with out the extra step...


L8R

Lots of great insight here.

So, how far should a "healthy" slave cylinder push the clutch fork forward when depressing the clutch pedal? I have one that I'm trying to inspect through the bellhousing inspection window, but I have no idea of what's "acceptable" and what is "suspect." Thx