1973 3765 GT4 2+2 engine not running right | FerrariChat
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1973 3765 GT4 2+2 engine not running right

Discussion in 'Technical Q&A' started by Nembo1777, Mar 19, 2022.

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  1. Nembo1777

    Nembo1777 F1 World Champ

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    #1 Nembo1777, Mar 19, 2022
    Last edited: Mar 19, 2022
    Dear all I need some help for a friend whose 365GT4 2+2 is having a temper tantrum.

    It is a tired car but it was running like a sewing machine before doing compression tests.

    The sparkplugs did not look good so were changed but the car would not start properly afterwards.

    It appeared the plug wires were dead so a new set was procured from Italy.

    The new, correct, plugs and wires were mounted, the coils seem ok, it misfires less but still won’t run properly?

    What could be the cause? The battery is fine in any case.

    Thanks in advance for any wisdom, I will be on the road today but my friend will be looking at this thread hoping for clues.
     
  2. wmuno

    wmuno Formula Junior
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    #2 wmuno, Mar 19, 2022
    The next thing to check are the points, condensor, and timing. Also, the distibutor has a mechanical advance; old grease can prevent it from working freely.

    If that doesn't solve the problem, then check the fuel system. This is a step-by-step process to eliminate one potential problem at each step.
     
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  3. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
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    #3 Steve Magnusson, Mar 19, 2022
    Have you double-checked and triple-checked that the firing orders are OK? Easy to get a couple of wires swapped when replacing the spark plugs and/or replacing the spark plug wires...
     
    Extreme1, Rifledriver, Llenroc and 1 other person like this.
  4. Nembo1777

    Nembo1777 F1 World Champ

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    #4 Nembo1777, Mar 19, 2022
    Thanks, yes I suggested they triple check that.
     
  5. Nembo1777

    Nembo1777 F1 World Champ

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    #5 Nembo1777, Mar 19, 2022
    Excellent thanks.
     
  6. raemin

    raemin Formula 3

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    #6 raemin, Mar 19, 2022
    Also these distributors are supposed to be lubricated: if you pull the rotor arm, you can see a "wick" (not sure about the proper english word) which should receive a generous amount of oil. This is how the axle and the advance mechanism are lubricated.

    This being said, I can hardly see how the distributor would seize during a spark plug change.

    The original champion plugs being not available anymore maybe a wrong alternative was chosen?
     
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  7. tbakowsky

    tbakowsky Two Time F1 World Champ
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    #7 tbakowsky, Mar 19, 2022
    choke stuck partly on? Stuck float in one of the carbs?
     
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  8. Nembo1777

    Nembo1777 F1 World Champ

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    #8 Nembo1777, Mar 21, 2022
    Hi all problem solved, old grease in the wrong places, not sure how to translate correctly but your help counted, many thanks!
     
    Jack-the-lad likes this.

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