I Think The Distributors Springs Are Near The Rondella | FerrariChat

I Think The Distributors Springs Are Near The Rondella

Discussion in 'Technical Q&A' started by donaldh2o, Oct 3, 2006.

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  1. donaldh2o

    donaldh2o Karting

    Nov 10, 2003
    143
    Irvine CA
    Full Name:
    Don
    #1 donaldh2o, Oct 3, 2006
    According to the 308 service manual the springs are somewhere in the distributor - and according to the 308 parts list, they appear to be near the "rondella."

    Service manual says: "Start the bench motor and gradually increase the RPM; check at which the speed the luminous ignition will start its moving on the scaled disc and, in this condition, the instant in which the advance mechanism starts operating, is achieved."

    "If the curve achieved is not equal to that shown in the diagram (fig.8), replace the counteracting springs."

    Ok, so I did it and it didn't achieve the curve so I guess I need new counteracting springs in both distributors.

    Does anyone know where I can get these springs?
     
  2. Rifledriver

    Rifledriver Three Time F1 World Champ

    Apr 29, 2004
    34,103
    Austin TX
    Full Name:
    Brian Crall
    #2 Rifledriver, Oct 3, 2006
    You need to reshim the springs. It was done by MM when they built them and I would bet that over the years when they were taken apart either the springs and shims got mixed up or the shims were lost.

    Sorting out a pair of distributors that have been in the hands of the unknowing can be a long PIA.

    Good luck.
     
  3. fatbillybob

    fatbillybob Two Time F1 World Champ
    Consultant Owner

    Aug 10, 2002
    26,415
    socal
    #3 fatbillybob, Oct 4, 2006
    Don,

    There is all kinds of crap in your distributor spring box area. You need to take the unit apart and the springs are in there. You need to put the dist on a proper SUN distributor machine and check/set the advance curves. Sometimes sticking springs from all the dried bosch distributor grease can kill the curve as can shaft vibration from back shaft bearings. If you are not familiar with this or do not have the machine then open and clean the dist and relube the springs and/or send it to a guy to recurve or check the curve. If they are ok after the clean out then you are done. If not then the guy can shim the springs or put different ones in there to match the curve. You need to send both dist. and have matching curves unless you are running the car on one dist. and an optical trigger like the xr700 crane/allison units. It is really not that hard but you have to pay attention to detail.
     
  4. Mike Florio

    Mike Florio Formula Junior

    Jun 19, 2003
    592
    NW Rural Nevada
    Full Name:
    Mike Florio
    #4 Mike Florio, Oct 4, 2006
    Each spring/pin is specific to a particular RPM range. They must be in the correct arm locations to function correctly. If you removed them to clean the old grease and didn't note where they go back you may have a problem.

    I did a write-up on this, available here:

    http://dino308gt4.com/downloads/distributoralign.pdf

    To get them right they must be set-up in a distributor machine. Two manufacturers are SUN and Allen. I'm particular to the Allen Synchrograph, probably becuse thet's the kind I have.
     

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