Clutch still dropping to floor after new slave

[WillMK7 10]

Evening chaps, after an extended stay at work to fit my new slave cylinder, still no joy :( WE bled the system with an eezibleed, no air what so ever. We clamped the in-feed pipe off and the master seals seem fine ( hard clutch ) We can get pressure on the clutch and drive it, but its really spongy and occasionally the pedal will not return.

 

Anyone have any idea why this is happening? Have we just not bled it properly? Please don't tell me its the master, I may cry. Anyone have experience with this?

 

Cheers,

Will

[VW_OwneR_85 1]

had a similar problem in that i could drive and change gear fine but after being on the clutch for say more then 20 secs the clutch pedal didnt like returning and at one point it did stay down,i couldnt tell if the master cylinder seals were leaking either , i could hold the clutch down for ages and the bite point wouldnt change... new master cylinder fixed it, i guess the seals deteriorated, theres obviously a chance it might not be the master but its a good place to start and if it looks old then chances are its the original one, IMO might aswell replace it as preventative maintenance seeing as theres a very high chance it will solve your issue

[WillMK7 10]

The thing is, when we clamp the inlet to the slave of and depress the clutch it won't budge. Which too me suggests the masters seals are fine? Or was it the same in your case?

[fendervg 30]

Could well be the master. I haven't checked recently but I seem to remember you can bleed both, but could be wrong. Also check the return spring and that it's not catching anywhere. The problem with brakes, like the cooling systems, is that they are sealed systems - from hard experience I have found that renewing just one component in the circuit will put an undue strain on the rest of the 20 year old system and inevitably something else will give as the system is now back to it's operating pressure. Once you mess with any one part, you need to be extremely careful. Just my two cents - but hope you find an easier solution.

 

EDIT - I use one of these - http://www.amazon.co.uk/Sealey-VS820-Clutch-Bleeding-System-x/dp/B000ROARTI - much better than hooking up to a tyre.

Edited August 18, 2015 by fendervg

[WillMK7 10]

It's the clutch not the breaks ah! But same principals :)

[fendervg 30]

Lol: - that's what I get for multitasking. The clutch is fed by the brake fluid reservoir via a hose, so it's actually the same system. Other cars have a separate clutch fluid reservoir.

[WillMK7 10]

I'm well aware of this, but thanks dude :) after spending four hours on it tonight I'm just a bit stuck. Just hoping it's our bleeding method... Otherwise it's the master :/

[fendervg 30]

No worries - I bled my whole system including brake callipers, ABS pump and clutch using the Sealey VS820 mentioned above without any issues at all. Never had much luck with an Eezzibleed.

[VW_OwneR_85 1]

yea fendervrg's got a point, as my clutch issue only started happening after i replaced my clutch hose, guess the old seals didnt like bleeding,

 

yea in theory that would suggest the clutch seals arent letting fluid past but that might not be why the pedals staying down , my test was just hold the clutch down for ages with the engine running and in gear at no point did i start to move or the bite point change so to me mine wasnt leaking either, i did have one moment when it first stayed down that i had to switch off the engine as it wanted to carry on reversing with the clutch on the floor! but that never happend again, just old components that are worn/deteriorated..

[WillMK7 10]

yea fendervrg's got a point, as my clutch issue only started happening after i replaced my clutch hose, guess the old seals didnt like bleeding,

 

yea in theory that would suggest the clutch seals arent letting fluid past but that might not be why the pedals staying down , my test was just hold the clutch down for ages with the engine running and in gear at no point did i start to move or the bite point change so to me mine wasnt leaking either, i did have one moment when it first stayed down that i had to switch off the engine as it wanted to carry on reversing with the clutch on the floor! but that never happend again, just old components that are worn/deteriorated..

 

 

So I guess my question should have been more like will the master cylinder cause me issues even if it seems to be fine :bonk: :bonk: I'm on the verge on insanity. Because my mechanical mind sees no reason why it should be the master aha. I will take it to the garage across from work tomorrow and see what they say.

[fendervg 30]

The seals on the master will have perished with age and will eventually give way - especially if it's bled at a very high pressure. I had a similar issue with an '87 Audi Coupe Quattro years ago and had to replace both the master and the slave to get it sorted. Your garage should at least have a decent bleeding kit, so that might help.

[WillMK7 10]

If I replace the master will I have to bleed the whole system? I can get a master from VW heritage for 36 quid so that's not a problem. It's fitting it, as I don't really have the time or space! Especially seeing as I'm going away and need the car by Friday :(

[WillMK7 10]

Re-bled this morning. No joy. So its at the garage now :( Hopefully I can drive her home tonight

[WillMK7 10]

Garage bled it and have got it down to an occasional sticking to the floor.... better than it was initially. They said maybe its the hose collapsing in under pressure? Any thoughts on that? Or does everyone still think its the master If so where's the best place to get one?

[VW_OwneR_85 1]

just replace it budd and the hose if it looks dodgy , its not hard to replace at all, this is the one i brought for my vr6, best check to see if it fits yours {cant see why not}, its made by bosch which is very good quality , theres cheaper ones out there but you pay for what you get..http://www.ebay.co.uk/itm/Clutch-Master-Cylinder-VW-CORRADO-53I-2-9-VR6-Coupe-190-BHP-Top-German-Quality-/400777974942?pt=LH_DefaultDomain_3&hash=item5d503a949e the only downside is i needed to thread tapp the bolt holes {pretty sure its M-8} as the master is held in by studs not bolts and that master cylinder didnt come with threads cut, i may of been able to use smaller diameter bolts and nuts but its fairly tight on the drivers side,

[WillMK7 10]

just replace it budd and the hose if it looks dodgy , its not hard to replace at all, this is the one i brought for my vr6, best check to see if it fits yours {cant see why not}, its made by bosch which is very good quality , theres cheaper ones out there but you pay for what you get..http://www.ebay.co.uk/itm/Clutch-Master-Cylinder-VW-CORRADO-53I-2-9-VR6-Coupe-190-BHP-Top-German-Quality-/400777974942?pt=LH_DefaultDomain_3&hash=item5d503a949e the only downside is i needed to thread tapp the bolt holes {pretty sure its M-8} as the master is held in by studs not bolts and that master cylinder didnt come with threads cut, i may of been able to use smaller diameter bolts and nuts but its fairly tight on the drivers side,

 

Not meaning to be rude.... but why would I need to tap the bolt holes? Surely it is just secured with nuts? Or am I missing something aha!

[VW_OwneR_85 1]

yea you could but you would either have to drill it out or use smaller diameter bolts as its the correct size to thread tapp for the current studs N nuts, how ever on the side nearset the drivers side its very tight and i didnt think theres room for a head of a bolt to stick out or room for a spanner , think thats why vw used studs? you might be able to idk have a look and see what you think at the time, i just thread tapped it and used the original nuts and then a stainless nut on the heat sheild so it looks new...

[VW_OwneR_85 1]

right so looking back ,you could just drill out the passenger side hole and use a bolt straight through and then jam a spanner on it to stop it from spinning as you do it up, but then you still might have problems with the drivers side bolt, at the time i thought thread tap was the only way,

[Bs6VR6 10]

Have to second the replacing it suggestion mate. Had exactly the same issue with mine, all was working fine, went to refit it a year later and a catalogue of issues trying to bleed it, first replaced the slave and still crap pedal, like yours soft and not returning correctly. Eventually bought a Delphi model off eBay, not the most expensive but certainly not the cheapest. Had the correct white plastic clip, so no need to replace pedal, bled it and bingo, perfect pedal straight away. Really not a hard job to replace. I would also do the feed line as well just to be sure. It's peace of mind, and you won't have to look at the system for years then. Mines been perfect since.

 

Cheers

[Dox 22]

Drove the Corrado to wickes yesterday for drill bits, then filled up with fuel and parked it in the street as I was working on the drive. 9PM last night after walking the dog I went to put the car on the drive and the clutch pedal was on the floor.... I manhandled the car onto the drive and noticed a puddle of fluid on the road where it was parked.

 

This morning I had a look and spotted fluid dripping out of the bellhousing = slave cylinder, went down to the shed and found an OE preloved cylinder, fitted it and its better than its ever been.

 

Prior to this the pedal hadn't been returning all the way to the top.