What could be causing this? T50 slave cylinder issue.

[joey]

Hey guys,
Had this happen twice to me today. This morning i was adjusting the nuts on the slave cylinder rod because i had set them wrong the first time and the the release point on the clutch pedal was way up the top, so screwed them down the shaft a little bit and was working fine for 2 or more clutch pedal pushes until it went mushy.
Thought the unit must be stuffed as ive never changed it before and just finished installing the new one today. Bolted it all up, bled it and then went for a spin down the road, was acting fine them bam... it went to mush again. Had a look underneath and this is what happened:


The piston has come out of the cylinder....
I assume this is what happened to the last one aswell as it had the same symptoms and when pushed down it just pisses out clutch fluid.
Any ideas on what could be causing this?

Thanks, Joe

[Dazza]

I think there is supposed to be a spring that goes through the hole in the end of your clutch fork then back to the slave cylinder so the piston in the slave cylinder returns properly. then you need to adjust the rod so it is longer.
If the clutch isn't working properly with the rod adjusted out longer then you may have a problem with the pressure plate or the clutch fork pivot ball might need adjusting out further.

[Dale]

Slave cylinder rod is too short, allowing the piston to come out of the bore

[JZX083]

two things to look at, the shaft on the slave being to short or perhaps you were saying it doesnt engage untill the top of the stroke on the pedal then maybe adjusting the master cylinder slave so it doesnt have as much stroke on it. But making sure there is enough throw to disengage the clutch....

[allencr]

Pressure plate or fork is broken, maybe the clutch fork's pivot.
Look at the bellhousing slot for the fork - no more room for travel!

It could also have been 'pumped up', a line restriction will allow the MC to continue drawing fluid from the resvoiur before the slave is able to completely retract & each pedal pump pushes the slave piston further out. Did the pedal get progressivly harder?

[joey]

I adjusted the nuts on the shaft out more and took the slave off and pushed the piston back in aswell as putting the spring on and bleeding again. Now the pedal feels like im pressing on air all the way down until about the last cm or so which it half engages.

[Dazza]

It could be a crook master cylinder. If the piston is sticking in the bore so it doesn't return fully you will have this problem.
Is this a new gearbox and or clutch setup? If so it could be that the master cylinder is too small ,compared to the slave cylinder.

[mattysshop]

i was going to say bent clutch fork.. but that bastard is cast!..

if you need a new rod made, drop me a PM with the dimentions and thread pitch./size, can turn one up at small cost..

[joey]

I'll take apart the master tonight and have a closer look to see whats going on. Thanks for the offer mattyshop, will see how we go.

Thanks guys

[joey]

Well the slave nor the master is the problem, they have both been replaced with new items now and still has the same problem. Must be something to do with the fork or something else inside the box

[mattysshop]

it looks like the slave is doing it's job correctly, look how far it's pushing the fork back into the bellhousing..

p/plate fingers collapsed? throwout/thrust bearing? is it a custom clutch? maybe the height wasn't set right.. or needs a thicker throwout bearing?

[twentyEight]

Will you be home this arvo Mr. Shabadoo?

I can come around and have a look if you like?

[Cuzzo]

Have you given the clutch a hard time recently or is the clutch pretty old?

You may be experiencing a totally fked / cracked pressure plate. Or the fork is bent / broken.

Is the clip holding the rod inside the end of the slave cylinder?

Has the clutch been working fine bfore this?

[joey]

Not a custom clutch, was just a new exedy heavy duty which was installed maybe 1.5 years ago but as this isnt my daily it should be no where near farked yet.
I finish work at 5, if you can make it after then that would be great simon, if not then no worries
Clutch isn't given a hard time. There is no clip or anything which holds the rod inside the slave, the piston end is concave and centralises the rod within it and the other end rests against the fork.
Clutch was working fine, but as i said the disengagment point was at the very top because i adjusted the rod length from the slave to this point but hadnt gotten around to changing this position until the other day and all this happened.

[Cuzzo]

There should be a clip im pretty sure..

[twentyEight]

Will be there about 5.15 Joey Jo Jo...

[Cuzzo]

Google images fails me, but its a c clip which holds the rod inside the slave.

[joey]

Google images fails me, but its a c clip which holds the rod inside the slave.

Hmmm well my old one didnt have one, nor did the new one come with one :S
No probs Sim-bob lol.

[takai]

Google images fails me, but its a c clip which holds the rod inside the slave.

Most T50 ones dont have these. They are just smooth bored, and then the clutch travel stops it from moving further. I had the same issue on my race car, i simply limited travel on the pedal

[CrUZida]

Make sure you open the bleed valve on the slave cylinder and the plunger is all the way at the rear before you adjust the rod.

If you keep adjusting things while the plunger isn't right at the back then it will slowly move forward.