mettalic rattle at idle | FerrariChat
Buy

mettalic rattle at idle

Discussion in '348/355' started by lotusk, Oct 16, 2008.

This site may earn a commission from merchant affiliate links, including eBay, Amazon, Skimlinks, and others.

  1. lotusk

    lotusk Formula 3

    Nov 3, 2003
    1,840
    London UK
    #1 lotusk, Oct 16, 2008
    gentlemen.................have noticed a loud metallic rattle with my 355 at idle....sort of comes and goes..once revs build up it disappears............maybe a heat shield rattling....if so anyone recommend which one to look at?.......everything is tight on the car...ideas????
     
  2. Husker

    Husker F1 World Champ

    Dec 31, 2003
    11,792
    western hemisphere
    #2 Husker, Oct 16, 2008
    Throw out bearing?
     
  3. f355spider

    f355spider F1 World Champ
    Owner Rossa Subscribed

    May 29, 2001
    18,055
    USA
    #3 f355spider, Oct 16, 2008
    Last edited: Oct 16, 2008
    Exhaust bypass valve. You can remove it and adjust the pre-load or tension to reduce or eliminate the rattle. About two turns out should do it.
     
  4. tactical

    tactical Guest

    Jan 23, 2008
    857
    #4 tactical, Oct 16, 2008
    One way to check that is to run the engine at idle with the clutch pressed in. If there is no noise then it would well be.
     
  5. lotusk

    lotusk Formula 3

    Nov 3, 2003
    1,840
    London UK
    #5 lotusk, Oct 16, 2008
    how loud is a thrust bearing or bypass valve rattle???
     
  6. Husker

    Husker F1 World Champ

    Dec 31, 2003
    11,792
    western hemisphere
    #6 Husker, Oct 16, 2008
    Assuming you mean the throw out bearing, the volume is going to be in the range of an 85 lb. German Shepherd barking from 30 feet away, with about a 7 mph downwind.
     
  7. Dr_ferrari

    Dr_ferrari Formula 3
    Consultant Professional Ferrari Technician

    Nov 2, 2003
    1,073
    Pocono Sportscar
    Full Name:
    Jim McGee
    #7 Dr_ferrari, Oct 16, 2008
    THREE BIG NOISEMAKERS:

    1 - SHIELD BETWEEN FRONT OF ENGINE AND FUEL TANK
    2 - MUFFLER BANDS
    3 - BYPASS VALVE

    Most likely one of the three.

    Regards, Jim
     
  8. James-NZ

    James-NZ F1 Veteran

    Jun 26, 2007
    5,822
    Hamilton, NewZealand
    Full Name:
    James
    #8 James-NZ, Oct 16, 2008
    Could be headers going bad, mine made a sort of rattle/ticking noise at idle. Wasn't very loud though.
     
  9. tactical

    tactical Guest

    Jan 23, 2008
    857
    #9 tactical, Oct 16, 2008
    Does the sound come from the front or rear of the engine bay by the way.
     
  10. sandersja

    sandersja Formula Junior

    Jan 16, 2003
    367
    Portland OR
    Full Name:
    John Sanders
    #10 sandersja, Oct 16, 2008
    For me, it was something that was loose in the otherwise-OK cats. Replacement Hyperflows fixed the rattle.
     
  11. whyte

    whyte Formula Junior

    Apr 25, 2006
    409
    Merritt Island, FL
    Full Name:
    John C
    #11 whyte, Oct 16, 2008
    Parking brake adjustment?
     
  12. 355dreamer

    355dreamer F1 World Champ
    Owner

    Apr 3, 2006
    10,476
    DC Metro
    Full Name:
    L.C.
    #12 355dreamer, Oct 16, 2008
    I would bet it is the valve. Mine does the same thing.
     
  13. hezgon

    hezgon Formula Junior

    Dec 13, 2006
    281
    Ft Pierce, FL
    Full Name:
    Stan
    #13 hezgon, Oct 18, 2008
    1 - SHIELD BETWEEN FRONT OF ENGINE AND FUEL TANK

    +1 this was the issue on my 1995, the rivets work lose. Easy fix. Louder as revs increase, now pure bliss.
     
    Weekender likes this.
  14. Marco Bussadori

    Marco Bussadori Formula Junior

    Aug 6, 2007
    430
    London
    Full Name:
    Marco Bussadori
    #14 Marco Bussadori, Oct 19, 2008
    Had this 2 months ago too... Rattles at idle (for me when the engine warmed up, not when cold) and through 1500-2000 rpm, then goes away.

    The muffler is segmented into chambers by baffles which have 4 spot welds keeping them in place. These sometimes do crack and the baffle resonates with a rattle sound.

    I had to cut away the edge of the exhaust (listen from which side it comes by listening to the exhaust tips), to then spot weld the baffle and reweld the case. Search for posts with my name for pictures.

    It is now 100% - I did remove a baffle at each side to let it flow a bit better and give more top end sound...

    Marco
     
  15. gothspeed

    gothspeed F1 World Champ

    May 26, 2006
    10,244
    U.S.A.
    Full Name:
    goth
    #15 gothspeed, Nov 18, 2008
    +1
     
  16. Loser

    Loser Formula Junior

    Apr 11, 2008
    791
    Gilroy, CA
    Full Name:
    Tom
    #16 Loser, Nov 18, 2008
    I actually had a rattle that I thought was the bypass valve, but it turned out to be that one of the bolts holding the Tubi exhaust in place had come loose.
     
  17. Oengus

    Oengus F1 World Champ
    Rossa Subscribed Silver Subscribed

    Sep 29, 2004
    10,854
    Between timing belts/chains or West Palm Beach FL
    Full Name:
    Chas
    #17 Oengus, Nov 18, 2008
    by pass valve............start there
     
  18. J. Salmon

    J. Salmon F1 Rookie
    Owner Rossa Subscribed

    Aug 27, 2005
    4,367
    VA
    #18 J. Salmon, Nov 18, 2008
    Mine does this too. Can anyone elaborate on the process of checking and fixing the bypass valve?
     
  19. DMOORE

    DMOORE Formula 3

    Aug 23, 2005
    1,720
    San Diego
    Full Name:
    Darrell
    #19 DMOORE, Nov 18, 2008


    Wire it in the open position. :).






    Darrell.
     

Share This Page