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Very strange .......

Discussion in 'Ferrari Discussion (not model specific)' started by TZ 750, Feb 8, 2010.

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  1. TZ 750

    TZ 750 Formula Junior

    Jul 18, 2009
    912
    #51 TZ 750, Feb 23, 2010
    Last edited by a moderator: Sep 7, 2017
  2. Fred2

    Fred2 F1 World Champ
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    Jan 2, 2005
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    nj
    #52 Fred2, Feb 23, 2010
    I am pretty sure that the plastic pieces were the bushing for the piston. The ring should fit in there.

    Can you take the piston apart to see if it was working properly?
    I would guess that it should allow fluid to flow in both directions.
     
  3. BigTex

    BigTex Seven Time F1 World Champ
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    Bubba
    #53 BigTex, Feb 23, 2010
    I agree.

    Looks like the seal decided to bind, and peeled from in between the rings.....
     
  4. TZ 750

    TZ 750 Formula Junior

    Jul 18, 2009
    912
    #54 TZ 750, Feb 23, 2010
    Last edited: Feb 23, 2010
    I think you are correct.

    Photo below shows the two remaining
    plastic parts on the piston, between
    the two "supporting," or "retaining" rings.
     
  5. TZ 750

    TZ 750 Formula Junior

    Jul 18, 2009
    912
    #55 TZ 750, Feb 23, 2010
    Last edited by a moderator: Sep 7, 2017
  6. BigTex

    BigTex Seven Time F1 World Champ
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    Dec 6, 2002
    79,408
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    Bubba
    #56 BigTex, Feb 23, 2010
    Let's see.....you just need that one seal and new housing tube! LOL!

    I don't think the Parts Book breaks it down, it says:

    Left Rear or Right Rear
     
  7. TZ 750

    TZ 750 Formula Junior

    Jul 18, 2009
    912
    #57 TZ 750, Feb 24, 2010
    Yup,

    that's part of the problem.

    Shock tubes are unavailable,
    except as part of a whole shock.

    Shocks at $1,012.00 EACH, sold in pairs ONLY.

    Have them in hand now, thanks to
    quick and helpful service from RICAMBI.

    (I have reason enough to want to replace
    both shocks - which I will discuss soon,
    with more photo's.)
     
  8. BigTex

    BigTex Seven Time F1 World Champ
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    Bubba
    #58 BigTex, Feb 24, 2010
    I'd agree, if any design updates were made, a matched pair would be the way to go....

    You don't want the OTHER side blowing out!

    I think car makers will sneak in upgrades that way, and avoid a recall.
     
  9. TZ 750

    TZ 750 Formula Junior

    Jul 18, 2009
    912
    #59 TZ 750, Feb 24, 2010
    Last edited by a moderator: Sep 7, 2017
     
  10. matkat

    matkat Formula 3

    Mar 18, 2003
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    Dave McGuire
    #60 matkat, Feb 25, 2010
    When I saw the initial fracture(sorry first time I have looked at the thread) it seemed to me that the crack/fracture could have been caused by something inside the cylinder my rationale was simply based on the basically straight line crack and nothing else I surmised that if something was caught on the piston and was continually moving up and down thereby causing wear this would in turn cause a weak spot in the cylinder lining leading to an inevitable failure, it may well be a good idea to inform the manufacturer about this issue.
     
  11. buckminster

    buckminster Formula Junior

    Aug 18, 2005
    989
    On the water, SWFL
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    Nicholas Raftis
    #61 buckminster, Feb 25, 2010
    Last edited: Feb 25, 2010
    Background: Me - Automotive engineer with specializations in metallurgy, fabrication (welding), and failure analysis.

    That tube does not look like a casting to me. It looks like it could have been a failure at or around a seam. The seal that has been destroyed - that could have been done after the seam split. Doesn't the metal bulge outward on the tube? Tube manufacturing is still pretty archaic and you can have runs of tubing with just a "stick" weld and might function correctly until overstressed.

    I would send all data and photos to Ferrari. The engineering staff needs to look at this failure metallurgically and determine the root cause. They test these parts for millions of miles under extreme conditions and this kind of failure should never happen.

    Brilliant investigative undertaking by the way. Now all you need is a metallurgical lab to section the tubing and look at the grain structure of the metal in various areas and chemically analyze, and report back. The only problem is that the manufacturer knows the specs. on the materials and we don't.
     
    MKnightMD likes this.
  12. BigTex

    BigTex Seven Time F1 World Champ
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    #62 BigTex, Feb 25, 2010
    Great thread!!

    Wouldn't hurt, to drop the Technical Group a note with pictures and see if they are interested....

    Rifledriver is laughing now....:D :D :D
     
  13. TZ 750

    TZ 750 Formula Junior

    Jul 18, 2009
    912
    #63 TZ 750, Feb 25, 2010

    I agree.

    I am still quite puzzled by the actual failure mode,
    but I am even more puzzled about how that
    shock body could have developed such
    a high internal pressure in the first place.

    I find it hard to believe that the power steering pump
    alone could supply that pressure without
    blowing lines all over the car ?

    Anybody have any thoughts ?

    Scott
     
  14. Fred2

    Fred2 F1 World Champ
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    #64 Fred2, Feb 26, 2010
    The bottom part of the shock rod is a valve.
    It is supposed to restrict the flow of fluid to provide damping.

    IF that valve was restricted, it would generate big pressure as the suspension moved.

    I would take that valve apart to see how it works (or does not work)
     
  15. TZ 750

    TZ 750 Formula Junior

    Jul 18, 2009
    912
    #65 TZ 750, Feb 26, 2010
    Last edited by a moderator: Sep 7, 2017
    Good idea !

    I'll take a look over the weekend, hopefully.

    World Soupers start this Sunday, so the
    big screen will be calling.......

    In the meantime:

    You will see that part of this plastic
    "piston ring" is missing.

    What's up with that ?
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  16. Fred2

    Fred2 F1 World Champ
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    #66 Fred2, Feb 26, 2010
    That part of the bushing may have been blown out the of the shock body.
     
  17. TZ 750

    TZ 750 Formula Junior

    Jul 18, 2009
    912
    #67 TZ 750, Feb 27, 2010
    Last edited by a moderator: Sep 7, 2017
    Hhhmmmm.........Well, yes.

    I just wonder what could have been in there,
    other than the parts of the shock.

    The plastic "piston ring"
    it pretty insubstantial,
    and not very thick.
    Image Unavailable, Please Login
     
  18. TZ 750

    TZ 750 Formula Junior

    Jul 18, 2009
    912
    #68 TZ 750, Feb 27, 2010
    Last edited by a moderator: Sep 7, 2017
    Anyway, while we had a break,
    we started putting things back together.

    We used the old two-sockets -and-a vise method
    of taking out the sperical bearing from the bottom
    of the old shock, and putting it into the new shock.
    Image Unavailable, Please Login
     
  19. TZ 750

    TZ 750 Formula Junior

    Jul 18, 2009
    912
    #69 TZ 750, Feb 27, 2010
    Last edited by a moderator: Sep 7, 2017
  20. TZ 750

    TZ 750 Formula Junior

    Jul 18, 2009
    912
    #70 TZ 750, Feb 27, 2010
    Last edited by a moderator: Sep 7, 2017
    Since the locking / adjusting rings are aluminum,
    and so is the threaded portion of the shock body,
    we put on some NEVERSIEZE anti-gauling compound
    as an assembly lube.
    Image Unavailable, Please Login
     
  21. TZ 750

    TZ 750 Formula Junior

    Jul 18, 2009
    912
    #71 TZ 750, Feb 27, 2010
    Last edited by a moderator: Sep 7, 2017
    Took a break from assembly, and took a few photo's
    of the measurements of the "split" in the shock body.

    Of interest is that at 90 degrees each side of the split,
    the tube is swollen up by almost a full milimeter.
    Image Unavailable, Please Login
     
  22. TZ 750

    TZ 750 Formula Junior

    Jul 18, 2009
    912
    #72 TZ 750, Feb 27, 2010
    Last edited by a moderator: Sep 7, 2017
  23. TZ 750

    TZ 750 Formula Junior

    Jul 18, 2009
    912
    #73 TZ 750, Mar 3, 2010
    Last edited by a moderator: Sep 7, 2017
    Good idea - let's do that !


    Here's where we start:

    The working end of the shock, the piston assembly,
    with a VERY tight nut on the end.
    Image Unavailable, Please Login
     
  24. TZ 750

    TZ 750 Formula Junior

    Jul 18, 2009
    912
    #74 TZ 750, Mar 3, 2010
    Last edited by a moderator: Sep 7, 2017
  25. TZ 750

    TZ 750 Formula Junior

    Jul 18, 2009
    912
    #75 TZ 750, Mar 3, 2010
    Last edited by a moderator: Sep 7, 2017
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