1975 308 GT4 idle starts normal, as car warms up rises to 2000 | Page 2 | FerrariChat

1975 308 GT4 idle starts normal, as car warms up rises to 2000

Discussion in '308/328' started by Thomasio, Mar 4, 2018.

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  1. Pero

    Pero Formula Junior
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    Apr 22, 2011
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    Peter R
    That would indicate an electrical problem. Rotor, cap, plugs etc., but it is an easy check and you could exclude a problem area. With a strobscope just walk through all ignition wires to see that you have an even constant spark.
    From memory........, I think that some unscrew the fast idle adjustment screw so that is not in contact the carb mechanism, not using it at all. I think it was Birdman, but this is also from memory...
    Does your car have some US extras like air pump, cat or others? Would love to see an engine bay picture.
    Welcome!
    /Peter
     
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  2. Pero

    Pero Formula Junior
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    Do you have original set up with points, condensors etc.? One or two distributors?
    /Peter
     
  3. Ian Bishop

    Ian Bishop Karting

    Dec 3, 2017
    156
    I may be missing part of the conversation here, but just a thought... if you recently purchased this car was there a PPI done or any 30 day warranty from the seller (a dealer it appears). I would contact them and ask if the PPI has a warranty for at least the cost of the PPI (should cover paying a technician to fix) or ask the dealer to address / fix or if not local pay someone to address if sold as mechanically sound.
     
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  4. absostone

    absostone F1 Veteran
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    Jul 28, 2008
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    I also suggested this to thomasio via text
     
  5. Prugna

    Prugna Formula 3

    Nov 13, 2014
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    Unites States
    It takes less time to unscrew the fast idle screw and confirm if that is the problem, than to analyze the fast idle system to determine if it is the problem.

    My vote is that the carbs are just a hair off of sync.

    Also, test for leak at hose from LR carb to power brake booster by pumping the brake pedal (only) whilst the car is ticking over.


    "From memory........, I think that some unscrew the fast idle adjustment screw so that is not in contact the carb mechanism, not using it at all. I think it was Birdman, but this is also from memory... "
     
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  6. Thomasio

    Thomasio Karting

    Feb 27, 2018
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    Thomas Alberti
    Two distributors. I believe it is all original, will be talking with the prior owner on Saturday.
     
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  7. Thomasio

    Thomasio Karting

    Feb 27, 2018
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    Thomas Alberti
    The dealer is willing to put some time into this. Unfortunately the weather turned here in Wisconsin, so it will be in our garage for now. So far, very happy with the dealer's response.
     
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  8. Thomasio

    Thomasio Karting

    Feb 27, 2018
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    Thomas Alberti
    Ordered an inductive plug wire tester. I want to confirm that each of the 8 cylinders are firing (cold). Will have the tester in a couple days and will update the thread. Other than the fast idle issue, the engine is very smooth and powerful. Intoxicating during acceleration.
     
  9. Thomasio

    Thomasio Karting

    Feb 27, 2018
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    Thomas Alberti
    Thanks Peter. It's a '75, no cats and I didn't notice an air pump but I can take a closer look soon.

    Here is a quick pic of the engine bay. Note the black plug wire on #1. The other wire had a broken connector at the spark plug, and this is a quick fix while I wait for the OEM wire set to arrive. (Car was running on 7 cylinders when I got it home, now is running on all 8.) Huge difference, as you might imagine.
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  10. absostone

    absostone F1 Veteran
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    Jul 28, 2008
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    that engine in your car is the first Ferrari I ever started and the first Ferrari I ever drove back In 2000. I hope I didn't break it! Lol
     
  11. Thomasio

    Thomasio Karting

    Feb 27, 2018
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    It will be cool for you to see it this summer after I sort a couple of things. Anyone have a rectangular Cromodora mirror?
     
  12. absostone

    absostone F1 Veteran
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    one or two on ebay it has different type of markings at the mirror pivot than original,and the base that mounts to the door is different
     
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  13. absostone

    absostone F1 Veteran
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    yes it would
     
  14. Thomasio

    Thomasio Karting

    Feb 27, 2018
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    Thanks. I figure I’ll wait for the correct one to come along.
     
  15. absostone

    absostone F1 Veteran
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    its identical though. original ones are hard to come by. Mine is worn out and cant withstand 50 mph with out going down to full aero mode. I need to find a way to replace the plastic ring that keeps tension on the arm
     
  16. Pero

    Pero Formula Junior
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    Is it the plastic ring inside a Cromodora Astro III you are looking for? Or do you just need to tighten the screw inside the mirror base? If plastic ring, let me know, I might have something useful.
    /Peter
     
  17. absostone

    absostone F1 Veteran
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    I believe small parts of the ring are deteriorated at the base on the door. You have s solution? That would be great. Thx
     
  18. Pero

    Pero Formula Junior
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    My thought was that I have a couple of rearview mirrors similar, but not Cromodoras, to Astro III. I have used parts from these in my own Cromo and I think that all dimensions are similar. Perhaps also the plastic rings. When you remove yours, send me a picture and dimensions and I will check if it works.
    /Peter
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  19. absostone

    absostone F1 Veteran
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    Where did you get those? they are the same. and the Astros are stamped on the bottom. those could be disassembled and chromed. Not sure when ill get mine apart, ill let you know
     
  20. Pero

    Pero Formula Junior
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    If you take it apart, just let me know.
    /Peter

    Sorry Thomasio for hijacking your post!
     
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  21. absostone

    absostone F1 Veteran
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    Ok yea me too
     
  22. Thomasio

    Thomasio Karting

    Feb 27, 2018
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    My car is garage-bound due to Wisconsin snow, but this morning I confirmed that at startup the engine is delivering spark to all 8 cylinders while idling nicely at 900/1,000 rpm. (One theory was that maybe all 8 weren’t firing immediately, and that when all 8 came online the idle would rise to 2,000).

    Next I will check the fast idle adjustment, which seems to me a bimetal spring that expands when it warms up to actuate a lever.
     
  23. absostone

    absostone F1 Veteran
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    could be. good luck
     
  24. Thomasio

    Thomasio Karting

    Feb 27, 2018
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    Disconnected the fast idle mechanism, the same issue persists. Also, with a cold engine, turned key only far enough to engage fuel pump (car not running). Looked into the four carbs to see if there was any fuel dripping, there was not.
     
  25. absostone

    absostone F1 Veteran
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    are you bringing it back to continental Saturday?
     

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