RPM needle | FerrariChat

RPM needle

Discussion in '365 GT4 2+2/400/412' started by JMFC, Nov 21, 2016.

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  1. JMFC

    JMFC Rookie

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    The RPM needle stopped working all of a sudden.

    Any clues. How would you fix it?

    Thanks
     
  2. Ferraridoc

    Ferraridoc F1 World Champ Owner Silver Subscribed

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    It means your engine is off
     
  3. simon klein

    simon klein Two Time F1 World Champ Owner

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    ....and this is precisely why you're a doctor.
     
  4. Ak Jim

    Ak Jim F1 Veteran Owner Rossa Subscribed

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    Could be that the tachometer is broken or a wire has broken or come loose.
     
  5. JMFC

    JMFC Rookie

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    Thanks AK Jim.

    Any pointers to address the problem?
     
  6. Newman

    Newman F1 World Champ Consultant Owner Professional Ferrari Technician

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    Lol
     
  7. Ak Jim

    Ak Jim F1 Veteran Owner Rossa Subscribed

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    Well if it was my car here is what I would do. I would start off going here Wiring Diagrams 308 365 400i 512
    and get an electronic copy of your wiring diagram. Your profile isn't filled out so not sure what car you have but they have diagrams for the 365 GT4 and 400i.

    I would then trace the wire on the diagram to see where it goes and then look for the wire in the car and see if I could visually see any thing like a loose or broken wire.

    If I didn't see any thing obvious I would take the instrument panel out and then look at the wires hooked up to the tach.

    I'd then take my dwell meter which also has a tach function and connect it to the wires on the tach in the car and then start the car.

    If my dwell meter showed an RPM reading then I would ascertain the tach was bad. If the dwell meter didn't show an rpm reading I would further investigate to wiring in the car.

    Definitely not an easy job but not impossible.
     
  8. aidanparte

    aidanparte Formula 3

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    You could remove the instrument panel - not too tricky - to access the tachometer and disconnect it. Then rev the engine and see if the jobby is turning - I'm assuming it is mechanical!
     
  9. Ak Jim

    Ak Jim F1 Veteran Owner Rossa Subscribed

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    Not sure when they changed over but our cars have electronic tachs.
     
  10. ricar116

    ricar116 Formula Junior

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    Mine is mechanical 1974
     
  11. Ak Jim

    Ak Jim F1 Veteran Owner Rossa Subscribed

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    Interesting, must have changed for 1975.
    POS computer. I have tried posting this picture multiple times. I rotated and saved the picture in all orientations and it is still upside down.
    Image Unavailable, Please Login
     
    Last edited by a moderator: Sep 7, 2017
  12. aidanparte

    aidanparte Formula 3

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    It's perfect for our Australian chums.
     
  13. simon klein

    simon klein Two Time F1 World Champ Owner

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    Yep,thanx for clearing THAT up!
     
  14. Newman

    Newman F1 World Champ Consultant Owner Professional Ferrari Technician

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    you beat me to it....
     
  15. bjwhite

    bjwhite F1 Rookie Silver Subscribed

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    You must be a Mac user. :)
     
  16. Newman

    Newman F1 World Champ Consultant Owner Professional Ferrari Technician

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    Can't be a mac if he said POS, it can only be a PC ;)
     
  17. JMFC

    JMFC Rookie

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    Thank you Ak Jim and aidanparte for your constructive inputs.

    Wishing you all a very Happy Thanksgiving!
     
  18. Ak Jim

    Ak Jim F1 Veteran Owner Rossa Subscribed

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    iPhone 6S and the computer is an Ailenware Area 51.
     
  19. Ashman

    Ashman Three Time F1 World Champ Owner Silver Subscribed

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    Southern hemisphere car? ;)

    The only hack I have for a iPhone is to copy the picture onto a word document right side up and then save the image from there. Then the image seems to attach correctly. Beats standing on my head to look at the picture! :)
     

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