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550 clutch job woes - is a new flywheel neccesary?

Discussion in '456/550/575' started by ///Mink, Apr 30, 2020.

  1. ///Mink

    ///Mink Formula Junior

    Sep 5, 2006
    742
    Fair Oaks, CA
    Full Name:
    Tom Mink
    Hi all. Having some issues with my clutch replacement process on my 550. I purchased an OE Ferrari clutch disc/PP kit (194775) and a Hill Engineering TOB. I bought the clutch from a shop owner who was going to use it for his personal car but didn't. He is familar to many here on FC.

    I took the parts to my local Ferrari tech (Well known and recommended guy with 35 years Ferrari experience) and after the job was done he said it was impossible to engage reverse with the engine running. His inspection indicated that the pressure plate surface had some runout in it that was not allowing full disengagement of the disc. I spoke to the guy I got the clutch from and he insisted that a new flywheel is required on a 550 clutch job for this very reason.

    So who is correct? I'm kind of stuck between two people here (Both of whom are reputable) and all I have to show for it is a broken Ferrari.
     
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  3. pkl03

    pkl03 Formula Junior
    Silver Subscribed

    Nov 29, 2004
    332
    Australia
    I would be going back to the mechanic that installed the clutch. He should have checked the condition of the flywheel when it was all apart - this is normal practice.

    Being a Ferrari mechanic with 35 years experience, he should be well advised to have informed you if it is mandatory to replace the flywheel prior to installation when you engaged him to undertake the work.

    It’s a cop out for him to tell you what the problem is after he has put it back together.


    .
     
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  4. brogenville

    brogenville Formula Junior
    Silver Subscribed

    Apr 24, 2012
    847
    UK
    Full Name:
    Robin
    I always get the flywheel reground when I’m doing a clutch. Cost in the uk is under £100 and you have a good as new flywheel. The amount of material that is removed is negligible, but it brings the surface back to as-new.

    Top tip though- make sure you retain the factory balancing marks.
     
    tres55 likes this.
  5. AVIMAX

    AVIMAX Formula Junior

    Aug 5, 2014
    531
    Toronto
    Full Name:
    Ryan
    Mine worked fine with a new clutch and original flywheel.
     
  6. EastMemphis

    EastMemphis Formula Junior
    Silver Subscribed Owner

    May 25, 2019
    819
    Memphis, TN
    Full Name:
    John
    Maybe a few spirited runs with high RPM starts would "grind" your clutch and flywheel enough to solve the problem. It might take 1 or 2 percent knocked off the clutch to let it fully disengage. Just don't go anywhere you have to backup!

    I'd at least try it before spending another couple grand to get the job done right the second time.
     
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  8. AVIMAX

    AVIMAX Formula Junior

    Aug 5, 2014
    531
    Toronto
    Full Name:
    Ryan
    Maybe I'm missing something, but if the clutch won't fully disengage for reverse, why would it for forward gears? Either the clutch disengages or it doesn't. If no problem with the forward gears, maybe the shift linkage isn't properly adjusted and so not allowing you to select reverse?
     
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  9. hwyman

    hwyman Formula Junior

    Jun 25, 2015
    255
    Canada / Los Angeles
    +1 on the resurface at a minimum while its out of the car. Also I agree with Avimax, a clutch either disengages or doesn't..... its fishy that it only doesn't disengage Reverse. Does it bind or grind even a little in the forward gears?
     
  10. yelcab

    yelcab F1 World Champ
    Consultant

    Nov 29, 2001
    10,521
    San Carlos, CA
    Full Name:
    Mitchell Le
    Reverse has no synchro ring and that is why it is very noticeable when you try to shift into it and it … grinds.

    Back on topic, a new flywheel is not mandatory when you do a clutch. However, with a brand new clutch plate and a brand new pressure plate, the pressure plate has to move "a full distance" away from the flywheel in order for it to disengage the flywheel and the clutch plate. At this point, you just need to drive it a few hundred miles to wear in the clutch plate and the pressure plate so that they will work properly. Be sure you bleed the slave cylinder of air. Press the clutch pedal all the way depressed as far as it would to, and shift slowly into the next gear. If Reverse is grinding so much to bother you. Turn the engine off, shift into reverse, clutch pedal down and restart the car. Yes, it is a bother but it will get better as the new clutch wears in.

    Why do I know this? It just happened to me.
     
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  11. ///Mink

    ///Mink Formula Junior

    Sep 5, 2006
    742
    Fair Oaks, CA
    Full Name:
    Tom Mink
    Well I paid him a visit yesterday and drove the car. The clutch actuation and takeup are absolutely perfect, there's no chatter, no weirdness in the clutch operation whatsoever. However, the problem is not limited to reverse as I mentioned before. The car cannot be put into first OR reverse with the engine running. The only way is to kill the engine and start it in gear. Then you can let clutch out and it all feels normal. Once underway, shifting between gears is notchy and abnormal.

    We put it up on the lift with the inspection panel removed and observed the full throw of the clutch arm - it's getting full travel. As an experiment, he adjusted all of the free play out of the clutch and it still will not fully disengage. He had another mechanic run the car on the lift with the clutch engaged and there is a very very obvious runout on the mating surface of the pressure plate with the clutch pressed in. The outside of the pressure plate has no such runout.

    So I guess it really looks like a defective pressure plate that won't fully disengage even with full pedal actuation. Just my luck.
     
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  13. nicholasn

    nicholasn Formula 3

    Nov 7, 2013
    1,788
    North Carolina
    Full Name:
    Nicholas
    At a complete stop, does it go into any of the other gears smoothly with the engine running? It would be very strange for this to be limited to 1st and reverse.
     
  14. ///Mink

    ///Mink Formula Junior

    Sep 5, 2006
    742
    Fair Oaks, CA
    Full Name:
    Tom Mink

    No, I neglected to mention that I tried 2nd and 3rd while stopped with no luck.
     
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  15. yelcab

    yelcab F1 World Champ
    Consultant

    Nov 29, 2001
    10,521
    San Carlos, CA
    Full Name:
    Mitchell Le
    Explain that to me. What does it mean run-out of the pressure plate.
    Yes, a new part can be defective.
     
  16. ///Mink

    ///Mink Formula Junior

    Sep 5, 2006
    742
    Fair Oaks, CA
    Full Name:
    Tom Mink
    I will post a video of it tomorrow. Easier seen than explained.
     
  17. ///Mink

    ///Mink Formula Junior

    Sep 5, 2006
    742
    Fair Oaks, CA
    Full Name:
    Tom Mink
    Just to close the loop - a new clutch kit fixed everything. The old pressure plate was a factory defect apparently. Yay me.
     
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  18. pkl03

    pkl03 Formula Junior
    Silver Subscribed

    Nov 29, 2004
    332
    Australia
    Great to hear.

    When you say a new clutch kit, do you mean an entire new kit or just a new pressure plate.
     
  19. hwyman

    hwyman Formula Junior

    Jun 25, 2015
    255
    Canada / Los Angeles
    Glad its fixed Tom sucks to hear you lost all that time and money on a defective part. Hopefully it runs perfectly for a while and you can put this behind you.
     
  20. yelcab

    yelcab F1 World Champ
    Consultant

    Nov 29, 2001
    10,521
    San Carlos, CA
    Full Name:
    Mitchell Le
    I'm not jumping on your case..., this is one time when "bring your parts" to the mechanic did not work out. If you had just let the second mechanic source his own parts, the whole thing would have been all done when you picked your car up. The bad part, and its warranty is on him.
     
  21. ///Mink

    ///Mink Formula Junior

    Sep 5, 2006
    742
    Fair Oaks, CA
    Full Name:
    Tom Mink
    Fact. That's actually what I had him do the second time around, just in case we got another bad one. What can I say, I gambled and I lost.
     
  22. tazandjan

    tazandjan Three Time F1 World Champ
    Lifetime Rossa Owner

    Jul 19, 2008
    33,046
    Clarksville, Tennessee
    Full Name:
    Terry H Phillips
    We have all done that. I just threw away a piece of factory CF that was unsalvageable, so do not feel too badly.
     
  23. MotoMeccanica

    MotoMeccanica Formula Junior
    Rossa Subscribed Silver Subscribed

    Aug 21, 2006
    408
    Calgary Alberta
    I just finished the clutch in my '95 456GT at the beginning of this week, and have the same issue. It will not engage reverse will running, I have to shut the car off. I'll drive it for a bit and see what happens.................

    Scott
     
  24. ///Mink

    ///Mink Formula Junior

    Sep 5, 2006
    742
    Fair Oaks, CA
    Full Name:
    Tom Mink
    If you can engage 1st gear and otherwise drive the car normally, I think it'll probably wear in. In my case I couldn't get into either 1st or reverse while running. It was also very difficult to shift gears while moving.
     
  25. MotoMeccanica

    MotoMeccanica Formula Junior
    Rossa Subscribed Silver Subscribed

    Aug 21, 2006
    408
    Calgary Alberta
    Mine shifts just fine, just cannot engage reverse while running. FYI, and I did the flywheel

    I'm not to worried, it will sort out
     

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