333pg333

I have been having a strange issue with my clutch and just wondered if anyone else has experienced something similar. It does a couple of weird things but both would be connected.
The pedal mostly sits up where it should but when you depress the pedal, the pressure point of engagement will randomly drop down 3-4 inches.
Also what seems to happen is that I can be accelerating hard in a gear and I go to change up/down and the pedal goes further to the floor. I have even had to pick the pedal up from the floor with the toe of my shoe once or twice.
We have bled it a few times which it does seem to respond to, yet there are no signs of leaks. We have swapped out the hydraulics from another car, and then put in a new master/slave assembly.

The pp is one supplied from Markus Blaszak and the clutch disc is from Clutchnet. It does chatter a bit on slow changes, reversing etc. It also periodically gives of the stench of clutch even on really light
loads. Like reversing or just really slow traffic moves. Weird.

So if anyone has had something like this, please post your results.
thanks

TRP951

I had a similar problem it turned out that the slave cylinder seal was partially torn and would let air in the system. A new slave cylinder solved the problem

George D

Agree with RTP951. Try reverse bleeding at the slave cylinder. Get a squirt can and put a hose on it's end. Remove the bleed screw from your slave cylinder and pump into that hole with the squirt can. Pump your pedal a few times and continue to reverse bleed pumping the squirt can making sure that your pedal is fully extended. Continue doing this until you see your tank almost full.

Telling me that you smell a burning disc is stating that it's not fully disengaging. Air in your system will do this. I'll bet a buck this will at least help. If this doesn't work, you probably have a PP issue, but this sounds like air not getting out. A reverse bleed should push the bubbles into your tank. Give it a shot as you will soon have a new disc on order.

When you said you bled it twice, I assumed you did this from the tank, not the slave cylinder.

Let me know how this works out.

gt37vgt

yeh defiantly one of the hydraulic cylinders

JohnKoaWood

When mine did the same thing, new master / slave / line fixed it for me too.....

Maybe you got a bad one out of the box??

gt37vgt

I can probably throw a slave cylinder in the mail .. save you buying or climbing under the grey wreck..

Tom M'Guinn

It does sound like the hydraulics. Check the carpet under the clutch pedal (or that area if you don't have carpet) as the master can leak into the cabin. In any event, if you bleed it to where it feels fine for a while and then the pedal starts getting lazy after awhile, I'd just start over with a new master, slave and hose in between. Changing any one of those will encourage the other two to fail if you don't do them all together.

kab996

When mine did this there was no sign of failure with the master or slave, I replaced both and all was well.

Bleeding helped but the symptoms would quickly return.

333pg333

Thanks guys for the input. No sign of leaks yet, but we'll have a real good look. Most everything has been changed or swap tested. I've got a feeling it's mechanical and not hydraulic.

What's the next step up from a stock clutch/disk. People use the 930 disk but there's no difference to the compound, just springs yes? I've heard good things about that Sounthbend outfit. Do they just supply disks or the whole assembly?

gt37vgt

well theres not much mechanical in there Pat just the fork pivot and posibly thrust bearing .
is the clutch net disc to chattery when your posing around the cross ? realy i have one and i was wondering..
the 930 disc is probably a different compound but it is defiantly a thicker disc this will result in more p reload ..I've got a centerforce dual friction disc here somewhere .. you can throw that in if you like ...

blown 944

Southbend is good for resurfacing a stock (preferable cup) disc with feramic material. I think they sell the Sachs PP but don't quote me on that. They also rework the stock PP to be a higher clamping force if you choose that route.

ausgeflippt951

The Cup disk will be sufficient to a fairly high hp level, IIRC. I'm running Vitesse St. 3, Cup disk, Fidanza FW, and KEP st. 1 PP and it holds just dandy.

BTW whenever I read your or gt37's posts I always read them in my head with an Australian accent...

Tom M'Guinn

Right, they resurfaced a cup disk for me, and supplied a reworked Sachs (factory) PP with higher clamping force. The set up has a "near" stock feel and has held solid up to an estimated 425rwhp (based on prior dyno runs). Threre is no chatter if I give it a smidge of gas before pulling out the clutch. I can induce a little chatter by letting the clutch out at idle and giving it lots of gas as it engages -- but I can do the same with a little more effort on my daily driver 3 series. For anything less than a monster motor, I'd be tempted to try a normal Cup disk with the Southbend reworked PP -- I suspect that would hold plenty of power and engage just like a factory clutch.

Having said all that, I still think this is most likely a hydraulics issue, especially if bleeding helps for a little while.

333pg333

Thanks guys, that gives us enough to go on. Not sure if Southbend exports Down Under. If needed we might have to get one of you good people to ship it to us. Pre paid of course.

Van

I once had a cantankerous clutch bleeding experience... I'd replaced the line from the master to the slave, and after several bleeding tries, it still wasn't good. Turned out, because of the the way the line went up from the master, and then down to the slave, it was trapping air at the top. Even when I used the motive, it didn't get that air out. (The volume or pressure wasn't enough to force the air bubble all the way down to the slave.)

I had to disconnect that line from the master, hold it upright, get fluid in there, etc. In the end, I finally got it.

I like George's idea of "reverse bleeding" - that should get out the air bubble I'm talking about.

p.s. love that CDX wheel spacer!!