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So long story short, I work at a dealership and was able to use a rack today and my plan was to replace the master and slave cylinders for the clutch. Unfortunately, as you all probably know, the master cylinder is a pain in the butt. I started at 7 and got the new one in and hooked up at 12:15. By this point I had 45 minutes so I bled the slave cylinder, cleaned everything up and....the clutch has no feel whatsoever and it won't go into gear. I got help from my master tech and we bled the slave cylinder a second time and nothing happened. At this point the shop closed and I had to get a ride home and now my Alfa is stuck. :cry: As far as I know I did everything correctly. Is there a step I am missing? Any help is massively appreciated!

One other thing to note, I was using a power bleeder and when that was hooked up and had pressure (around 15psi) the clutch felt absolutely normal. Disconnect it and the clutch was dead again.
 

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Bleeding hydraulic clutch systems is often problematic. What I do is reverse fill. I use a 60 ml syringe and connect it to the clutch bleeder with a short length of hose. Fill the syringe with fresh brake fluid, crack open the bleed screw and push fluid from the slave up to the master. Make sure there is room in the reservoir so it doesn't overflow (brake fluid will eat away at paint) This method pushes air up to the master - the way it naturally wants to go. Trying to fill the system from above (via the master cylinder) means you are trying to push air down.

Once the system is filled by reverse filling, a few pedal strokes to bleed out any trapped air bubbles will usually finish the job. Make sure the reservoir does not run down - otherwise you'll have to start all over again.
 

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Not to insult your - or the master tech's - intelligence, but you did install the slave cylinder so its bleed screw is oriented at 12:00, right?
 

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Discussion Starter #4
I didn't get around to installing the new slave. I ran out of time. But yeah I did read that it needs to be installed with the bleed screw at 12:00. One thing I did notice was that when I went to bleed the slave, it spun every time I tried to loosen the bleeder nut. I had to gently clamp it with pliers to make it stay still. Maybe the spinning disoriented it or something?
 

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The slave can spin freely in the bore of the bellhousing - that in itself won't cause any problems, as long as the bleed screw is at 12:00 at the time you bleed it.
 

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Did you have good fluid flow out of the bleeder? If not the hose could be twisted which will block flow.

If that is OK then grab the end of the release fork and try to move it backwards and forwards. It should barely move.

If that is OK then watch the movement of the release arm when your assistant pushes the pedal up and down.

If the arm is loose then it has probably come off the pivot inside the clutch housing. Shine a light through the rectangular hole to see what is going on.
 

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Discussion Starter #8
Ok! Will do. I won't get a chance to look at it till tomorrow as the shop is closed today. I'll update you guys when I can. Thanks for the help!
 

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Hi
So I second all the stuff the other posters said and
went to bleed the slave, it spun every time I tried to loosen the bleeder nut. I had to gently clamp it with pliers to make it stay still. Maybe the spinning disoriented it or something
That's right you have to secure the slave cylinder when you're bleeding it, just another annoyance of this job which is total PITA as you're fiding out. I clamp a long vise grip to the slave and that holds the slave cylinder in one position. That position being bleeder at 12:00 clock.

Anyway like the other posters say the trick is to force the brake fluid into the slave and not the master.

I get a long length of clear tubing (10 feet) from HomeDepot and attach that to a ladder or to the lift, several feet above the slave. I then fill that with brake fluid and open the bleeder.

The problem is always air in the slave.

Hope this helps
 

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ive sucsessfully power bled these systems with a few tricks

teflon tape is your FRIEND, wrap the thread of the bleeder, this will keep you from sucking air past the threads(more common of an issue than youd think) its NOT used as a fluid seal just a air seal for bleeding and youll have to re-do it next time anyway
pedal position can be everything, more often than not while youve got positive suction youll need to actuate the pedal VERY slowly and never bottom out in many cases there is a "sweet spot" where you can get good flow while locking the pedal most of the way down

my own air trap trick thats fixed issues multiple times on alfas, and a reason ive added a bleed T at the masters, teflon tape the threads of the slave, hook up a line into a container of fluid, now in my case i bleed to my T thus bleeding the master and slave at the same time, but in your case you a small pointed tip adapter usually found in the mighty vac setups, and stuff it into the port down in the fluid of the master and pull fluid thru, this is similar to the syringe setup except that you dont have the chance of blowing a hose off etc

if your replaceing the slave and dont know when the hose was replaced...do yourself a favor and replace it, i have had those bastards become 1 way swolen valves..fluid flows 1 way only or just bad enough that you think youve got a failed master/slave when its actualy just the hose
 

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I understand that you are beyond this but I just thought that this is a good thread to mention this. I always bench bleed a master cylinder before I install it. Make "blocking plugs" from either old brake-clutch fluid tubes and ferrules, or new parts. You can hammer-flat and fold the ends of the tubes, but I prefer to solder the ends closed. Then make tubes with ferrules that will reach down into a cup with brake fluid.. Clamp the MC in a vise, cobble together a way to feed fluid into the MC if there is no attached reservoir, install tube(s) so that they reach down into the cup making sure that the bottom of the tubes are just covered with brake fluid. Slowly push the piston shaft in and out until the fluid discharged into the cup is free of any air bubbles. Remove the bleed tube and quickly install the blocking plugs. Leave the block slightly loose, and while making one more pump, allow any air and then fluid to exit while you tighten the block. If the MC is good, and the procedure is done properly, the piston shaft will have only a very small amount of movement before it moves no more. Install the MC on the car. As quickly as possible remove the block and install the chassis line catching any spilled fluid with towels. Then bleed the connection at the MC using the - open line, push down, close the line, let up method. Catch the spilled fluid with towels. Do this method starting at the front, working back to the calipers or the slave. This method can be a bit cumbersome, and requires a helper, but it works every time for me. Good luck with your project.
 

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I like that the slave cylinder rotates in the housing. I hold it in place with a 1 1/16" AN wrench while I tighten the hose and the bleed nipple. To disconnect the hose I simply holding it tight with a 17 mm wrench then unscrew the cylinder. It is very convenient for replacing a cylinder or removing a transmission. I also have an old slave cylinder that I cut up and welded the fluid port closed. I screw that onto the hose to seal it while it is disconnected from the cylinder.
DSCN1231.JPG
 

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Discussion Starter #14
Ok. So we tried bleeding it directly through the hose to the master cylinder as one of the techs who helped me before said he was sure it was just air in the master cylinder. No go. Then we buckled down and replaced the slave cylinder as well which was also bad. (The piston fell out as we were removing it:ROFLMAO:). Bled it again using the pressure bleeder into the hose to the master cylinder...And the clutch is still dead. When pushing the pedal, my master tech got underneath and said that the the slave cylinder isn't moving at all. I assume this is air in the system somewhere? The only thing that wasn't the way it should be is that the slave got installed sideways. I did twist it to where the bleeder was up when it was open, but when I stop holding it with vice grips, it twists on its side. Don't know if that would have any effect.
 

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After it is bled of air it doesn't matter what position it is in. But if you are describing rotating the slave to put the bleed screw uppermost with the hose attached you may be twisting the hose and closing it off internally.

Have you tried the reverse fill method described in reply #2?
 

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Try bleeding it the old fashioned way with one person pushing down the pedal and the other opening and closing the bleed nipple. Does any fluid then come out of the nipple? If not then the hose is most likely blocked, something that happens easily if you twist it.
 

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We have not tried the reverse bleed method as I don't have a syringe. Even if I did, I am confused as to how to attach it to the bleed nipple. Do you just buy a really big one that will fit over it?
Well, I am a retired ER nurse - I got lots of useful stuff... What I use is called a 60 ml catheter tip syringe. You might be able to get one from a veterinary supply store or a nurse/doctor friend. The tip is like a narrow funnel shape. Slip a short length of plastic tube onto the syringe to fit onto the bleed screw. Reverse fill has not failed me yet - MG's, Alfa's, even a Peugeot.
 

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I bought a pack of cheap syringes to lube the bearings and prime the oil lines when I rebuilt a two stroke motorcycle engine and now I find myself using them for other garage tasks. They are a useful addition to a tool set.
 
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