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The $1,900 vibration noise in my 328...

Discussion in 'Technical Q&A' started by rob lay, Dec 18, 2003.

  1. rob lay

    rob lay Administrator
    Staff Member Admin Owner Miami 2018

    Dec 1, 2000
    48,995
    Southlake, TX
    Full Name:
    Rob Lay
    OK, as I promised, here's the story.

    About 3-4 months ago I started getting a vibration noise from the right side of the engine bay. It's not like vibration noises are unheard of in Ferraris, but this was a new one and was noticeable while driving. A few times I would take a gander, but never really pinpointed it.

    A couple weeks ago I had to take the car in after breaking the clutch cable. While it was in I told them to get the state inspection and also see if they could find the vibration.

    Long story short, it took a bunch of looking. I think Ken noticed a washer vibrating when he would rev it. Turns out that the bolt that holds the crank shaft pulley/dampener wasn't torqued down. It was lock-tighted, so it didn't come off, but there was enough play that the ridge in the pulley and the key were worn down. The vibration only started about 3 months ago, but it was getting worse and worse.

    What would of happened if we didn't find it?

    Anyway, a new crank shaft dampener goes for $1,800. Even Ferrari UK, who is famous for the best prices had them at $2,800. We ended up getting a used one from (maybe future sponsor) T. Rutlands for $1,200. All the other little parts and labor to find what was wrong and then reinstall everything added up to $1,900.

    My 328 had been almost perfectly reliable and inexpensive since I got it over 40 months ago. However, this was one expensive and unexpected event.

    Here's a pic of all the used parts...
     
  2. henryk

    henryk Formula Junior

    Dec 9, 2003
    479
    Door County, WI
    Interesting!

    I would have tried the following:

    Line up the damper in a press, with the proper key-hole cutting bit aligned, to the partially "loose" slot.....the inside corners should not have been moved.

    Then weld a small bead, using a MIG welder, on the walls of the damper.

    Finally, use the cutting bit to "re-slot" the hole to the proper depth.

    It would seem to me that the key-way material should be softer than the damper steel.......hence, it should have worn MUCH more than the key-way slot in the damper.
     
  3. rob lay

    rob lay Administrator
    Staff Member Admin Owner Miami 2018

    Dec 1, 2000
    48,995
    Southlake, TX
    Full Name:
    Rob Lay
    I couldn't really get a good close picture of the key. You can tell a little in the big pic, but the key was worn almost half the way through. The damper slot was perfectly straight on one side and the other side was at a very noticable angle.
     
  4. henryk

    henryk Formula Junior

    Dec 9, 2003
    479
    Door County, WI
    Since the damper only turns in one direction as the engine runs, I would suspect, as you have stated, that only one side of the slot was affected.

    The key-way cutting bit would then be aligned by both the bottom and the one good side. This would mean that one would only have to weld the bad side.

    It seems that my method would have a good chance of working.
     
  5. ronr

    ronr Formula Junior

    Oct 30, 2002
    801
    DFW, TX
    Full Name:
    Ron
    Rob,
    My car is STILL at Norwoods. I also took mine in for the oil change and inspection, and to get the radiator pulled and cleaned out so it won't overheat during the summer.

    I told them while you're at it, check out a few of these little nitpicky items that I haven't gotten to yet. So far, the bill is up to about $1600, and they didn't even pull the radiator. I think I'll just do that myself.
     
  6. rob lay

    rob lay Administrator
    Staff Member Admin Owner Miami 2018

    Dec 1, 2000
    48,995
    Southlake, TX
    Full Name:
    Rob Lay
    I saw your baby there yesterday. It's doing fine. I think there are two black 308's there right now.

    They also have Reggie Jackson's old F40. Beautiful condition. The Jag XJ220 is gone now.
     
  7. jimpo1

    jimpo1 Two Time F1 World Champ
    Silver Subscribed Owner

    Jul 30, 2001
    21,725
    Dallas, TX
    Full Name:
    Jim E
    Rob, when I saw the title to this thread, I wondered if that "$1900 vibration noise" had anything to do with why you found panties in your car! :D
     
  8. Mark 328

    Mark 328 Formula Junior

    Nov 6, 2003
    510
    Orange, Ca
    Full Name:
    Mark Foley
    Rob:
    At least you caught it before it flew-off.
    If you retorqued the balancer periodically do you think it would have not loosened-up?

    The periodic maintenance on some vehicles requires the harmonic balancer be periodically retorqued (VW Rabbit Diesels are one example).
    Next time I'm in the vicinity, I am going to retorque my balancer.

    Mark
     
  9. rob lay

    rob lay Administrator
    Staff Member Admin Owner Miami 2018

    Dec 1, 2000
    48,995
    Southlake, TX
    Full Name:
    Rob Lay
    The bolt wasn't torqued to begin with. It was locktighted and put on, but not torqued. So the bolt wasn't backing off at all, it just wasn't holding anything secure.
     
  10. speedmoore

    speedmoore Formula 3
    Professional Ferrari Technician BANNED

    Apr 15, 2003
    1,541
    Austin, Texas
    Full Name:
    D Moore
    Hey Rob,

    You should get down on your knees and be thankful.

    Have you priced up a crankshaft lately? Nevermind the labor.

    D
     
  11. rob lay

    rob lay Administrator
    Staff Member Admin Owner Miami 2018

    Dec 1, 2000
    48,995
    Southlake, TX
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    Rob Lay
    Does anyone know what would of happened if the key finally gave way?

    I don't know much, but I think the crank would keep spinning, but the pulley wouldn't. Would that interfere with cam timing? Oil pump?

    What would the worse case and/or most likely case be?

    Knowing how quick the noise started and how it kept getting worse, I don't think there was much time left. The key was literally 50% worn through on one side.
     
  12. davequick

    davequick Formula Junior

    May 27, 2003
    307
    Bellevue, WA
    Full Name:
    Dave Quick
    Is it his "old' F40 meaning hea actually sold it? I saw it on TV not meet it's reserve at the barrett jackson auction.

    -dq
     
  13. speedmoore

    speedmoore Formula 3
    Professional Ferrari Technician BANNED

    Apr 15, 2003
    1,541
    Austin, Texas
    Full Name:
    D Moore
    It could easily screw up the end of the crankshaft causing a teardown and either weld repair and reheatreat or replace the crank. The pulley coming off or the key completely breaking would either quit spinning or take out the water pump, a/c, and alternator belts. Waterpump not spinning would over heat the car in a hurry.

    Cambelt are not attached to that pulley, nor do they have a gear on the end of the crank like a TR. They are driven internally/geared to crank. So I don't see how they could be affected unless the vibration of the dampner caused the crankshaft to break thus crashing valves....and that is not out of the realm of possibilities.

    D
     
  14. rob lay

    rob lay Administrator
    Staff Member Admin Owner Miami 2018

    Dec 1, 2000
    48,995
    Southlake, TX
    Full Name:
    Rob Lay
    Yes, it was just bought a few weeks ago. It really is in beautiful condition.
     

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