QV clutch slave cylinder | Page 3 | FerrariChat

QV clutch slave cylinder

Discussion in 'Mondial' started by jeffQV, Feb 21, 2012.

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  1. soucorp

    soucorp F1 Rookie

    Sep 20, 2011
    4,814
    Old Dominion
    Full Name:
    Mike
    Hi Bill, if you compare the new unit with the old, are you noticing a big difference in throw of the pistons? When I compared mine, it was very similar in the measurements, thus I had no problems.
     
  2. bshaw

    bshaw Karting

    Nov 3, 2003
    65
    Connecticut
    Full Name:
    Bill
    I didn't compare them, the new one is installed, the original is on the bench right now. The pictures are exactly what you have posted. I replaced it because I found quite a bit of fluid in the dust boot while I was changing the clutch disc and pressure plate.

    Now in thinking about it I'm wondering if I have a problem with the master.
     
  3. Russ Gould

    Russ Gould Formula 3
    Silver Subscribed

    Nov 8, 2004
    1,073
    #53 Russ Gould, Jun 25, 2012
    Last edited: Jun 25, 2012
    I struggled to bleed my clutch the "old fashioned way", ie open bleed screw, pump pedal, close bleed, pull pedal up (I had the return spring uncoupled to allow one man to do the job) and so on ad nauseam. It didn't work, just gave my back and thighs a workout. Then I remembered my "gizmo", essentially a piece of tubing that clips onto the bleed valve, with a non-return ball valve at the other end, which is placed in a jar. Once this was in place, I opened the bleed valve (after removing the front distributor cap and rotor to get access), pumped the pedal vigorously and got the system bled in no time. (Plan B was to resort to a pressure bleeder but this would have pushed all the old fluid up into the master, which would have defeated the purpose of the exercise). I don't have a vacuum bleeder and that's probably the best way of all.

    Now since you are not getting clutch release even with hard pedal (ie properly bled system), you should check the following:

    1. Check the slack adjustment on the master cyl pushrod ... it is adjustable (you need to be a midget and/or remove the front seat to get under there on your back) by means of a locknut. You should take up any slack. This will give you a better throw. Get someone to operate the clutch while you observe the slave ... the clutch lever only moves an inch or two and that's all it takes to operate the clutch.

    2. If that doesn't do it, your clutch friction plate may be frozen/stuck to your flywheel. This happens if you let the car sit for too long. A year will do it. The remedy is to start the car in gear, work up thru the gears by timing the changes, then when you get to 4th, depress the clutch and stab the throttle repeatedly until the clutch breaks free. It's surprising how stubborn a stuck clutch can be. Not sure what makes it stick but when it's stuck, it's stuck really well.


    Don't be removing the master cylinder unless there is fluid leaking down into the footwell. Not too hard to take out the MC but tricky to put it back. For one thing, hooking up the line requires that the line be bent back into exactly the right orienation or the thread will not engage. This can take some trial and error. The clutch MC seals are unobtanium, so you will need to buy and entire MC unit and FNA charges the earth for one. You can get an Alfa Spyder unit but the reservior is round (dead giveaway) and the rubber boot may not fit thru the hole in the Aluminum housing. So you may need to reuse your old boot, as well as your old pushrod. And it's very hard to hook up the pedal again after you reinstall the MC. Believe me, it's like doing surgery upside down with your left hand.

    I don't think it's your slave cyl, a lot of guys have used the Lancia Thema and Fiat versions (with the old pushrod) and it works fine. The piston on your original slave should pop out (there's a spring in there) when you remove the circlip. If it doesn't, push the piston in and take a look down the bore with a flashlight to see why it's not coming out. It may just be the seal hanging up on the circlip groove. Worry it a bit and it will come out. You can get aftermarket replacement seals from T Rutlands I think for about $20, but be sure to give your cyl a hone to get rid of pitting/ roughness otherwise you will chew up your new seal. Getting new rubber bellows is impossible. So use your old one if it's ok, otherwise you will need to improvise. There's a guy by the name of Guido who posts here, who can supply you with a boot that will work after a fashion, but it does not clip onto the pushrod, it just allows the pushrod to slide in and out of the boot. You should also use a zip tie to secure it onto the slave, as there is no lip like the OEM part. Guido also has slave cyl seals that are the right size, but Guido's master cyl seals are not the right size and the inner donut seal (without lip) is impossible to get so don't throw yours out. As best I can tell, this donut seal is just a guide to keep the piston centered in the bore, so you can reuse your old one. You are on your own as far as the outer (lipped) seal. International Auto parts advertises a seal kit for the Alfa Spyder 81 that looks like it is the right kit, but the ad is theoretical, they don't have them and I gave up waiting after a year of "manyana" from IAP.
     
  4. bshaw

    bshaw Karting

    Nov 3, 2003
    65
    Connecticut
    Full Name:
    Bill
    Thanks Russ (and Mike!) for your input.

    The friction disc and pressure plate are new last weekend so they're not stuck. I did check movement at the slave, with my wife in the driver's seat (first time in 13 years!), the car up on the lift and the left rear wheel off. With the engine running it will not go into reverse on its own movement. I grabbed the lever with my big adjustable and got just a bit more movement and it slid right into reverse with no problems.

    I'll check for slack in the master adjustment this evening, here's hoping for success there. I priced the master - $575! Here's hoping I don't have to go there!

    Bill
     
  5. Russ Gould

    Russ Gould Formula 3
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    Nov 8, 2004
    1,073
    New driven plate and new pressure plate = a clutch that requires max travel to disengage ... hopefully these were the correct items otherwise if the driven plate is too fat (aftermarket copy) you may be SOL. In that case you may have to make up a custom slave pushrod (or if it's right on the borderline you may be able to wear it down a bit by driving badly). If it's the aftermarket slave that is the root of the problem, you may need to change out the slave again. Just a thought ... you did reuse the original factory slave pushrod, right?
     
  6. bshaw

    bshaw Karting

    Nov 3, 2003
    65
    Connecticut
    Full Name:
    Bill
    Yes, factory pushrod.

    I adjusted the master rod about 3/8" out - took out the slop. No change. I'm going to run it out some more when I get back out there again, but I think it's getting close to the end of the adjustment range. We'll see.
     
  7. Russ Gould

    Russ Gould Formula 3
    Silver Subscribed

    Nov 8, 2004
    1,073
    3/8" is a lot of slop, I think perhaps your MC piston is not returning to zero position when you release the clutch. That could explain why you are not getting enough fluid (movement) at the slave. What happens is the MC corrodes a bit on the open end as it's exposed to air and the fluid attracts moisture, so esp if it weeps a bit you get a rough cylinder at that point. Then your piston/seal hang up on the roughness and won't return all the way. Try "bouncing" it out using your clutch pedal and see if that makes a difference (you may need to adjust the rod to put the slack back before doing this). If it's corroded, your cylinder will start to leak if it has not already done so. Is there fluid inside the MC boot? If so, take out the MC and sort it out. (As stated previously, I don't know where to get a seal/boot kit so you may be looking at a new MC). If not, the "bouncing" may free the piston up enough to get you going, at least for a while.

    Final thought, if the pedal is not nice and hard, you may have to bleed the system again.

    Final final ... sure you did the clutch R&R properly? Warped pressure plate?
     
  8. fdekeu

    fdekeu Formula Junior

    Jun 19, 2008
    582
    Belzium
    Full Name:
    Frank
    I bought the Metelli 54-0037 yesterday
    on eBay from IDIR in Italy
    18.5 + 11 euro for shipping
    for my Mondi 3.2
    Will keep you informed
    I am also going to disassemble the 'old' original one and try to repair it
     
  9. fdekeu

    fdekeu Formula Junior

    Jun 19, 2008
    582
    Belzium
    Full Name:
    Frank
    I disassembled the original slave
    It was stuck midway
    Succeeded in getting the piston out after some time
    Bore is Diameter 20.5mm, stroke about 60mm
    I am now waiting for the Metelli 54-0037 to arrive

    I have a mondi coupe and accessed the slave from the wheel side
    No problem to disassemble it that way
     
  10. fdekeu

    fdekeu Formula Junior

    Jun 19, 2008
    582
    Belzium
    Full Name:
    Frank
    I have installed the Metelli and the cluch works again
    The pressure point is way down now

    I noticed the Metelli is a lot better quality than the original one, so
    I am going to repair the original cilinder by making a new piston with better seals
    I will have to increase the bore a bit because of wear
    I have found quad rings that will fit a bore of 20.8mm
    Actual is about 20.6mm diameter

    Since the EPDM seal withstands 150°C I suppose temperature is not the reason they
    fail
     
  11. Wade

    Wade Three Time F1 World Champ
    Owner

    Mar 31, 2006
    32,793
    East Central, FL
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    Wade O.
    That's good info.

    I tried the Alpha slave and had the same experience as you. Someone here sleeved the bore (stainless, I believe), have you considered that as well? Otherwise, corrosion may be a recurring problem.
     
  12. fdekeu

    fdekeu Formula Junior

    Jun 19, 2008
    582
    Belzium
    Full Name:
    Frank
    Good point Wade

    I am looking at using 2 quad rings (same as Metelli) so there will not be a lot of contact between piston and bore
    Material will be bronze or steel, unless somebody can convince me there is a better alternative (also depends on what the 'lathe' guy can come up with)
    No sleeve in the Metelli so I think it is not necessary unless you want a 100 years of lifetime
    I like to repair it every 10-20yrs

    What Duc do you have?
     
  13. Wade

    Wade Three Time F1 World Champ
    Owner

    Mar 31, 2006
    32,793
    East Central, FL
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    Wade O.
    Right now I have 2007 S4RS Monster. :)

    http://www.ferrarichat.com/forum/140965870-post243.html
     
  14. fdekeu

    fdekeu Formula Junior

    Jun 19, 2008
    582
    Belzium
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    Frank
  15. mulo rampante

    mulo rampante Formula Junior

    May 31, 2011
    997
    Terra Incognita
    Full Name:
    Charles
    Just a quick comment: The Metelli part will give you a release closer to the floor because of its larger bore diameter. Mike (Soucorp) and I have used that part and it works fine for us.

    Rebuilding the original is definitely a good way to get things in spec. (As would resleeving a Matelli).

    When I was doing my research I found a Volvo clutch slave that appeared to be perfect, with the proper bore diameter, save that the hydraulic fitting was at a different angle, and might have been a different size banjo union as well. I also couldn't get any data on the O.D., so I didn't risk the $100 or so to see if it would fit. If I find my notes on this I'll post it up.

    Interesting that you guys have a Monster and a 999. I was seriously looking at either a Duc or an Aprilia before I bought my Mondial instead. No regrets really, I'm to old to be laying on a gas tank :)
     
  16. Wade

    Wade Three Time F1 World Champ
    Owner

    Mar 31, 2006
    32,793
    East Central, FL
    Full Name:
    Wade O.
    Well, I had a 1098S but a drunk driver took out my Jeep with me in it. So far, the only lasting damage is that I can no longer ride in the Superbike (crouched) position. So, sold the S to a airline pilot in Prague. The Monster, however, has a much more upright riding position i.e. suitable for us oldies and cripples ;)

    The S4RS with its 999S motor is the perfect urban hellion as well.

    But, alas... it's time for the Monster to go (nowhere fun to ride where I'm currently located).
     
  17. Wade

    Wade Three Time F1 World Champ
    Owner

    Mar 31, 2006
    32,793
    East Central, FL
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    Wade O.
    I loved the 999, especially in black :)
     
  18. spbogen

    spbogen Karting
    Owner

    Aug 23, 2007
    92
    Charlotte, NC
    Full Name:
    Bob
    ..for contributing to this thread.

    It gave me enough information to replace my clutch slave.
    I just put in the Metelli 54-0037 ($32 instead of $350+). Definitely a lower release point but it works just fine and I now have time to repair the original one.

    A note on bleeding - I could not use a pressure bleeder as fluid was pushed out of the reservoir through the fluid level sensor seal (really glad I had towels wrapped around the reservoir.
    I ended up using a MightyVac connected to the bleed screw which pulled most of the air out. I finished it off with the method of loosely holding my finder over the bleed hole, depressing the pedal and then pressing the finger down tightly when releasing the pedal.
     
  19. mulo rampante

    mulo rampante Formula Junior

    May 31, 2011
    997
    Terra Incognita
    Full Name:
    Charles
    #69 mulo rampante, May 30, 2013
    Last edited: May 30, 2013
    Glad it worked for you. The Metelli part can't be beat as a stopgap measure while the original is rebuilt. Considering the amount I drive, mine is a more-or-less permanent fixture until I get around to replacing it. I've had no problems.

    A few posts ago (and some months ago) I had alluded to a Volvo part that might be made to work. This discovery came about as I searched for clutch slave cylinders that were the same mounting style as the Ferrari part, and had a 20.6 mm (13/16") bore. There aren't a lot out of parts out there that meet this specification.

    I might try this in the future, but I still don't know enough about the parts to determine if it would be an easy swap. Certainly, the first person to investigate this will be in uncharted territory.

    Here are the details:

    DELPHI Part # LL49905, 20.6 mm piston diameter. Used on Volvo 940 and 960 from the early 90's that have the 2.8 litre inline 6 motor. Note that vehicles equipped with other engines use a larger dia. cylinder bore -- I think 22 mm, so be careful. The part is similar in appearance to the Ferrari part, and the outer diameter is almost certainly the same. I believe the banjo fitting may be a larger size than the Ferrari (and Metelli) part. The hydraulic fitting mounts to the 'top' of the cylinder. Retail in the USA seems to be around $100.

    Also...

    Some BMW 2002's also used a similar-appearing slave cylinder, also with a 20.6 mm bore. From what I can tell, this part is found on ti and tii models early on, and appears to be standardized on all models by 1974 or so. The retention scheme on this and might require the fitting of an external snap ring (aka Seeger ring), and it may be that the retaining block would require modification in order to retain it. I have no idea as to the size of the hydraulic fitting. It is nonetheless a good candidate for further investigation. The hydraulic fitting mounts to the top of this cylinder in the same position as the Volvo part. Part numbers are Centric # 138.34000 and Beck Arnley # 072-0938. These seem to sell for around $60 USD.

    Anyone got a 2002 that they can make some slave cylinder measurement on? :)

    And again, as if it isn't abundantly clear from what I've written above, these are merely the best (and only candidates) from my research on the subject. Installation of either would almost certainly require some modifications. As some of the older Ferrari parts are at risk of becoming unavailable, something like this may be our best recourse to keeping things working as close to "stock" as possible.
     
  20. MvT

    MvT F1 Rookie

    May 25, 2013
    4,248
    The Netherlands - NH
    Full Name:
    Tijn
    Hi guys,

    I have read this entire post as I have some trouble in getting the clutch released at all with a new flywheel and clutch kit. The push rod seems to be cut when I looked at it and I was wondering if someone can tell me the orignal (from end to end) size of the push rod and diameter of the original clutch slave cylinder as the one on it has one of 25.3mm, which is way to much. I have a 3.2 QV.

    Thanks in advance,
    MvT
     
  21. mulo rampante

    mulo rampante Formula Junior

    May 31, 2011
    997
    Terra Incognita
    Full Name:
    Charles
    #71 mulo rampante, Aug 1, 2013
    Last edited: Aug 1, 2013
    Sorry, but I don't have that measurement. Perhaps someone else will provide this. The original rod didn't look particularly nice on mine, and others have noted this, but I think it is due to the manufacturing process. The end does not have a 'nice' radius on it.

    Just curious, what clutch kit did you use? Did the flywheel require resurfacing?

    Slave dia from Mondial 8/QV Workshop Manual: 13/16" = 20.54 mm diameter, Maximum stroke 44.5 mm.

    Some ratio calculations... (hope my math is right)

    The ratio of the areas between the clutch master and slave is what determine the ratio of the strokes. If you just consider diameter, it can be deceiving, as the relationship is not linear, but of course varies with the square of the radii. This is my analysis with various clutch slaves:

    Original:

    master = 11/16" dia = 17.46mm, total stroke = 30mm. Slave = 20.54mm
    ratio of areas (slave/master) = 331.3 / 239.3 = 1.385

    Metelli slave with a 23.81mm dia bore:

    ratio of areas (slave/master) = 445.0 / 239.3 = 1.860
    This represents 34% more master cylinder travel for the same amount of slave movement.

    1 inch Alfa cylinder, approx 25.4 mm bore:
    ratio of areas = 506.7 / 239.3 = 2.117
    The 1" slave will require about 53% more master cylinder travel for the same displacement at the slave end. This has worked for some, but others report the clutch releasing with the pedal right at the floor. No surprise.

    If you can find a 0.875" (22.23mm) slave cylinder that works, the ratios are much more favourable:

    ratio of areas = 388.1 / 239.3 = 1.622
    This is a mere 17% increase in master cylinder travel compared to the original part.
     
  22. MvT

    MvT F1 Rookie

    May 25, 2013
    4,248
    The Netherlands - NH
    Full Name:
    Tijn
    #72 MvT, Aug 2, 2013
    Last edited: Aug 2, 2013
    Thx Mulo rampante!

    I bought a genuine clutch kit from the Ferrari dealer here. As far as it is genuine as they get it from an OEM supplier in Italy. Anyway the price was about the same without shipping costs as from Superformance.co.uk. However, now I have a year warranty eventhough I did the repair myself.

    I have a new flywheel as the one I took out was cracked all over the place. See link below (post #49). New flywheel was presurfaced (Post #62) If the old one didn't had cracks I would have need to. It would be recommended to do it at all times btw.

    http://www.ferrarichat.com/forum/mondial/280494-mondial-not-letting-me-into-gear-during-long-drives-3.html

    I have a cylinder with 20.58mm diameter. Let me see if this works good... ...If I can get a push rod from somewhere :( Now try to extend it for the time being.
     
  23. mulo rampante

    mulo rampante Formula Junior

    May 31, 2011
    997
    Terra Incognita
    Full Name:
    Charles
    MvT: Thanks for the info on the clutch kit. After I re-read your first post I realised that you had replaced the flywheel.

    Wade had a situation similar to yours, and he provides the overall length measurement of the original rod, as well as a side-by-side comparison with a new rod. His thread is here http://www.ferrarichat.com/forum/mondial/352955-replacing-clutch-slave-have-dilemma-two.html

    If you find any more information that would be of use to the community, please post it.
     
  24. PV Dirk

    PV Dirk F1 Veteran

    Jul 26, 2009
    5,401
    Ahwatukee, AZ
    Very interesting. I know in CA and FL they have places called "pick and pull" where you select and remove your own parts at a good price out of a junk yard. Don't expect it would be too hard to remove from a Volvo for someone to try this out. Now the tii may be harder to find :)
     
  25. Jeka

    Jeka Formula 3
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    Nov 20, 2010
    1,176
    Rotterdam
    Full Name:
    Johan
    It's an old thread but it could be interesting to know the clutch slave of an Alfa GT 3.2 GTA does look like the Ferrari slave and even has a 20.6 mm bore. I ordered one just as a spare (the original slave is still fine but it looks like it is starting to leak a little bit). Part number: FIAT 46835408 or BOSCH 0986486573. The funny thing is the Alfa is a 3.2 as well :) It's a cheap part: 35 Euro.
     

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