Seat Ibiza Hydraulic Clutch

[enforcer]

Greetings vehicle gurus ...

 

Can anyone help with this one? Just replaced the wife's VW Bora 1.6 with a charming little 1.2 12v Seat Ibiza (Mk IV 2002) so that it's a little less painful for my son to insure on. I think the car is basicly a re-shelled VW Polo anyway. And there appears to be one whole cylinder missing as well

 

 

The clutch does its job perfectly well but the biting point is very low (about an inch off the carpet). I've read the Haynes and perused the forums and this afternoon I have had a good go at bleeding from the clutch slave cylinder. There are no obvious leaks at either end and I'm sure I got a few bubbles out, but no improvement. We could just drive it as it is, but for a young chap just learning to drive it's hard enough mastering the clutch biting point without it being an inch off the floor!

 

I read somewhere that the only way to fully bleed a slave cylinder is to press the piston hard back into the cylinder when you've finished the main bleed (in order to dispel any air left in there). I haven't tried this yet as I thought I'd pick a few wise old brains on here first (and I'd have to remove it from the transmission casing first).

 

I'm thinking the following as possible diagnoses:

 

Air remaining in the Slave?

Fault in the Slave?

Fault in the master?

 

I'm loathe to put it in to the garage yet .. I'm sure they'd replace everything!!!! Apart from this one issue the car's in superb condition and only done 53k. Grateful for any advice or observations!!

[Guest robinj66]

Not sure if it's of any help but on my first Leon (2000 plate) i had about 3 slave cylinders before the clutch was quite right. Apparantly they were plastic! Not sure if your Ibiza would still have this problem as it looks to be much later

[Guest MarkB]

sounds more like clutch kit to me, bent fingers on the pressure plate.

[Guest robinj66]

Have alook here Seat Cuprs Forums. May point you in the right direction

[enforcer]

Thanks for the replies folks ... keep 'em coming! Robin I read through that thread, thanks and strangely enough when checking the clutch pedal master cylinder I noticed that the clutch pedal switch was connected, but removed from the pedal ... it was just hanging down??? Now according to the guy posting on that thread, the switch adjusts the bite point. I can't believe that's true though since it is a two wire on/off switch and now that I have replaced it and checked the wiring it hasn't made any difference.

 

I've had a look online and it seems that the clutch pedal switch informs the ECU that the clutch pedal is depressed. This (apparently) disconnects the cruise control (I don't have it anyway), prevents over-revving while the clutch is disengaged and does some other stuff to the revs when changing gear. Nothing about the bite point (if only it were that simple). Since the clutch is a simple master cylinder to slave cylinder affair the low bite point can only be as a result of the 'throw' of the slave cylinder being too short, either through air in the fluid or a defective slave or master???

 

Or am I barking up the wrong tree?

 

Or am I just barking

[maccavvy]

so its just low and nothing else??

 

If you sit with it in gear and running with clutch down, does it creep at all??

 

Is it a hydraulic release bearing or a slave cylinder operating on an arm??

 

My van had a low biting point ,over 3 weeks it got lower and lower till i removed the box and found it was weeping fluid and letting air in.

[enforcer]

Yep, operates fine, just very low biting point. It's a hydraulic slave cylinder mounted externally on the transmission casing operating the clutch release fork.

 

No creep and no fluctuations in the idle when the clutch is engaged and disengaged in neutral. No sign of any fluid leaking anywhere in the system. The only place I haven't checked is at the end of the slave piston (inside the transmission). No slip either.

[agent_zed]

ok i'm probably missing something but here is my logic.

 

assuming no air in the system the pedal will sit where ever the fluid and pistons are set and move a set distance, from what you said it seems that it is working just very low biting point.

 

So i'm thinking is there some phyical adjustment on the pedal or piston end? as it may be necessary, as in your case, to move where the pedal begins to apply pressure. Perhaps some shims that sould be removed to move the master cylinder closer to the pedal?

 

of course it may just be set presumably in the 'correct' position forever and would suggest either air still in the system or clutch wear as suggested.

 

How does it work on the clutch?, on my punto the piston pushed on the release arm outside of the gearbox and was clearly visible.

 

hth

 

edit : you beat me and answered some of my questions

Edited October 2, 2011 by agent_zed

[Peter Bell]

Just a thought is the pedal coming right up to its rest position? ie no broken spring

[enforcer]

Thanks guys

 

There is no pedal travel adjustment at either end of the system.

 

The pedal returns all the way back to its stop.

 

The slave cylinder is mounted on the outside of the transmission, but the piston and gaiter are inside the bell housing (the end of the piston presses against one side of the clutch release fork. I'd need to remove the slave cylinder to examine it for leakage and functionality ... which is probably going to be the next course of action.

 

Rich

[maccavvy]

imo it will be weeping fluid from the piston rod end.

[Longboarder]

Couldn't just be a worn clutch plate, could it or knackered pressure plate as MarkB suggested. Does it have to be the hydraulics?

 

Nigel

[enforcer]

Couldn't just be a worn clutch plate, could it or knackered pressure plate as MarkB suggested. Does it have to be the hydraulics?

 

Might well be Nigel, and whilst the clutch kit is cheap enough it's a bit of a job getting to it. I'm going to rule out any other possibilities first but I may well end up having to replace it. I'll look into the slave cylinder this weekend.