Am looking for wise council please... My son's VRS developed a slow to return clutch pedal. To cut a difficult story short this has so far resulted in a new master cylinder, a new slave cylinder and since the slave was being done the clutch plate and dmf were also changed. 

 

The result has been no improvement at all... The pedal and return spring were looked at and all is good. The clutch damper/restrictor valve at the slave cylinder/bell-housing was removed, checked and even the restrictor in it removed in an effort to fix the problem but nothing changed.

 

It's been bled using an ezi-bleed set to a (high!) 30psi and litres of brake fluid later still not a single improvement.

 

Can anybody suggest what is being overlooked please as it has defeated two very experienced mechanics so far and I really don't know what do next.

 

It's a nice unmodified VRS and otherwise drives really well - it has only covered a genuine 68k from new too.

 

Hoping for some help/advice!

 

Cheers,

Jeff.

Edited 16 June, 20223 yr by Grafix
Title change

Wondering if it might be a flexi hose issue?

Am up for any suggestions! The flexi hose part 'looks' normal (no visible kinks or deformation) but can they degrade internally in some way? 

 

Cheers,

Jeff. 

7 minutes ago, Grafix said:

but can they degrade internally in some way? 

 

 

I've seen it happen with brake flexis. It's a tough one because you've done everything I would have suspected.

Cheers! Yes it's driving us mad as we really have run out of sensible ideas. Really though your suggestion is pretty much the only thing left! 

 

Jeff. 

Number one suspect will be the damper/restrictor AKA Clutch peak torque limiter, unlike a collapsed hose or internally corroded pipe or a partil blockage the torque limiter only restricts on the return stroke.

 

It is actually very nigh on impossible to remove the internals of the restrictor, if you can block it from rotating you can drill out the bore, I bet it is functioning and there is some debris on the slave cylinder side.

We did actually remove the little floating restrictor element from the clutch delay valve quite easily though? We saw it was the same as the VW part number used on Golfs (and Audi TTs) and copied a Youtube video to take it out - very easily to be honest? The trick is to remove be the vertical bleed nipple first and its easy to do?

 

Unfortunately it made no difference even though you can see straight through the 'delay valve' now and happily blow air through it from either end with none of the restriction it had before.

 

We are really stuck! 

13 hours ago, TMB said:

 

I've seen it happen with brake flexis. It's a tough one because you've done everything I would have suspected.

+1 on this - The hoses break down internally (invisible from the outside), and act as a rudimentary non-return valve.  I've had this before - usually in brake hoses, but also - in a clutch line on an R1 Yamaha.

 

As you've already removed the restrictor this is the only possible "one-way" restriction I can think of that could be left.

 

Good luck with fixing the problem!

Thanks for the tip! It really is about the only thing we haven't changed so I think we have to try it - I think though it means a complete clutch hose assembly - which is main dealer only and around £120?

 

Jeff.

@Grafix I was wondering about the clutch hose too. At that price from a Skoda Stealer maybe check out Aeroquip and/or Hel before buying?

Could you take the old one off and take it to someone to make the hose for you?

Would work out a lot cheaper

I'd like to do that if we could but as of Monday it's in use commuting every day as we ran out of time and so really we only have the weekends and nobody realistically can turn a custom hose around so fast. 

 

Jeff. 

Update....

 

It was the flexi hose causing the issue.... Once we took the hose assy off it we found it was partially blocked despite looking perfectly normal externally.  Had to order the complete hose assy from a dealer but the clutch is now behaving perfectly. An expensive lesson! 

 

Thanks for the help from you all on here!

 

Cheers! 

 

Nice one. How much was the hose assembly out of interest?

Sure - it was £102 from a main dealer - it's the entire assembly of rigid sections, damping volume and flexi hose - all the way from the MC to the slave. Not available in sections unfortunately. 

 

Cheers.

Thanks. Not cheap but at least it's solved the problem 👍