993Porsche

I just installed a new clutch-slave unit on my C4 and the peddle drops half way. Thus prohibiting me from engaging the gears. I bled the slave unit 5/6 times using a power bleeder and believe there is no air in the system. What in the world is going on folks? What am I missing?


Thanks,

Ken

Garth S

Could be air that migrated up to the master cyl - or a reservoir level that dropped too low during the bleeding .... regardless, it is a pain to bleed the master. What has worked for me is to top the reservoir to the nutz, reconnect the pressure bleeder, and second a helper to work the clutch pedal while you man the slave bleeder screw.
You open the screw while the helper depresses the clutch - then close .... and said helper slowly pulls the pedal back from the floor: after 5 or so cycles of this, the pedal firms up - and returns by itself as normal.
Keep an eye on the reservoir level, or this could start all over again

The slave piston can be forced all the way back by hand once connected to the line and prior to bolting to the bell housing - which is a 'pre-bleeding'; however, as the fun of installing it is now over, I would only consider that approach as a last resort.

guards red

Don't you need a Hammer to bleed the system as it's part of the brake booster circuit?

CarreraX

With BMW's I have found that sitting is the car and pushing the clutch in and out for 10 min or so will work out the bubbles that you cant get by bleeding. This sounds stupid but I assure you that it works on BMW's.

Toga

I would suggest to bleed again the slave cylinder. Chances are that you still have air in the circuit. No hammer is needed for that. Mine was going down to the floor, and I had to bleed it for a "looooong" time before it became "normal".

993Porsche

Thanks Gents, I'll give that a try this evening. Will update you later.


Ken

DJF1

Just another note on this, are you 100% sure you installed the slave cylinder correctly? The metal tip in the front of it has to be dead center and you will hear short of a click when it is properly installed. if you are a bit off then you need to reinstall. Its a major PITA to get it in properly and it would explain the issues you have if its not done right... Just another thought on this as I have gone through it myself

Toga

In this case, telling if I'm wrong, but would'nt you blow the "piston" out of the slave when trying the clutch if that piston doesn't push against the lever?

993Porsche

No, I'm not 100% sure. But looking at one of the past post pictures, it looks like the slave's pointed-end should go into the off-centered round hole of the fork. Right? So, should the piston be pointing straight out or off to the right side where the hole is?


Yes, I think that's exactly what happened to me. The picture below shows what happened to my brand new slave unit. I'd thought it was a defective unit. So, I'd sent for a new one. It should be here sometime today. So, how can I make absolutely sure that I install it correctly the next time?


Ken

DJF1

Ken the picture did not make it... My install was eons ago so i dont remember an offset position. Its pretty blind install as well and a bear to get to. Maybe someone who has done it recently can chime in? I remember the wise words of my mechanic crystal clear as to the importance if feeling that click in the correct position. I remember pushing it into position and although I thought it was correctly in, it was not and thankfully I did not blow it. To me in the correct position it felt like a snap on button type of feeling when the button snaps correctly. Sorry for your troubles...

ZombiePorsche44

This is exactly why I paid my mechanic 2 hrs of labor to get it right.....ZP44

AOW162435

Ken,
I did the same replacement two years ago - PITA. Did you pop open the rubber bellhousing 'door'? If I remember correctly, I was able to verify if the rod end was in the divot by looking through the opening with a mirror.


Andreas

Fred, Long Island

Needs to be bled.
If you installed it off center without a full mating of both slave and tranny surfaces at all, it would break off an ear when you pushed in the pedal....ask me later how I know.
If the slave rod tip is not presented with an obstruction or stop and you depress the pedal....you'll blow all the internals right out the end....ask me later how I know.
So bleed it again...keep the fluid level up in the reservoir.

993Porsche

I'm with you on that.

Man, I hope it didn't break off the ear of the fork. I guess that's what you mean. But the cylinder did come apart. I'm scared to death of what I'm going to find. I'll check it out. The second picture I got from one of the past posts.

Thanks everyone. I'll let you informed.

Ken

Fred, Long Island

Check your PM

For all others....No....the fork is not compromised!
Fred