I installed new master and slave cylinders today, and the slave is giving me all kinds of trouble. The first attempt I somehow missed the clutch fork, so the piston and spring inside the slave popped out which dumped all kinds of brake fluid inside the bellhousing. I took the slave back out and reinserted the piston and spring which I assume is ok since these are rebuildable? So I get it back together and give it a few test test pokes with the rod and all is good. I get the slave back on and start bleeding...The brakes are rock solid and the clutch feels fine, so I go to start it up and the clutch pedal slowly sinks to the floor. I start bleeding again...at this point I've searched every thread on the topic and tried every method (beside speed bleeders and air pump), I've been pumping and bleeding for hours and can't get the pedal back. I did notice a drip of fluid coming out of the lower inspection hole on the bellhousing, but I'm not sure if this is from the first failed attempt when I got fluid all over or if the slave is no good and now has a slight leak.

Is it ok to put a slave cylinder back together after pushing out the piston and spring?
What is the best method for bleeding? When I first got the pedal to feel decent I was pumping the pedal about ten times and then holding it to the floor, open bleeder until fluid comes out, close bleeder, repeat...but then I read the clutch can't be bled like brakes and to pump the pedal, leave pedal up/out, crack the bleeder, push the pedal to the floor, close bleeder, repeat. I tried both ways and neither are working right now.

 

Is the slave leaking fluid still?

If not, I always bleed my clutch like my brakes and have never had a problem. Have someone pump, pump, pump, pump, hold... release bleeder, tighten bleeder, repeat. Also need to make sure the clutch pedal isnt being let back up before you close the bleeder. Also need to make sure your master cylinder isnt running dry while bleeding.

Also if the fluid was completely drained, your master may have air trapped inside.

If youre familiar with bleeding brakes, im going to guess you screwed the slave up. Check a parts diagram and make sure you put all the parts back in.

 

this is what i'm leaning towards. When I put the slave in the first time and missed the clutch fork the bellhousing was gushing fluid. Now it's just a drip here and there, so I'm not sure if that's fluid from the first mishap or if I screwed up putting the slave back together and it's slowly leaking into the bellhousing again. Either way, I got a new slave coming in a few hours.

Do you think there could be air trapped in the master even if the brakes are rock solid? I have bled each wheel at least ten times. I did not bench bleed the master cylinder.

A leaking slave is the only thing that makes sense to me right now, I'll update when the new slave arrives and I try that out.

 

It's ok to reinsert popped piston and spring and reuse the slave cylinder, it happened to me too just like it was in your case. I too always have done bleeding similar to brakes. Also note that there is a divider in the fluid container so draining one won't affect the other (meaning you can't imply your master has no air because brakes are still fine). And as you replaced both master and slave, it would take quite some time to properly bleed clutch system (especially master cylinder). I'd imagine how torturous it'd be doing that all by a single person, so get a friend to help pumping the pedal.

 

I feel like I got it all figured out now. I replaced the brake master, not clutch master. I assume when I put in the slave the first time and it was working decent, the clutch master let go shortly after, increasing my confusion. The new clutch master will be here in a couple days and I broke down and bought a mityvac so we should be all good. Thanks guys.

 

Im a little confused. But if you replaced the brake master, make sure you bleed the brakes.