HELP...da LUGANO !!!! | FerrariChat

HELP...da LUGANO !!!!

Discussion in '365 GT4 2+2/400/412' started by dedo tanzi, Dec 7, 2018.

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  1. dedo tanzi

    dedo tanzi Karting

    Dec 16, 2013
    52
    Lugano - SUISSE
    Full Name:
    DEDO - Alfredo
    Dear Friends, I have replaced the main bushings, but in the technical manual of the 400GT, the Ferrari indicates in 4.8 kg, the tightening torque of the "small" bolts M 8 !!!
    Do you think it's possible? Is it perhaps a misprint ??? It seems too high this data !!!!
    Thanks, I do not really know who to ask !!!!
     
  2. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    25,037
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    Is this concerning the torque specification for nut #25 in this 400GT SPC figure?:

    Image Unavailable, Please Login

    Is the torque specification for nut #21 even higher? Nut #21 looks more like an M10 thread so 4.8 Kg-m might not be so strange for that one. Do they give different torque specs for nuts #25 and #21?
     
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  3. dedo tanzi

    dedo tanzi Karting

    Dec 16, 2013
    52
    Lugano - SUISSE
    Full Name:
    DEDO - Alfredo
    Grazie, STEVE

    Molto gentile...ho scritto ad un amico ingegnere , che lavora in Ferrari a Maranello ....per avere la sicurezza ....
    Poi ti farò sapere la risposta della esatta coppia di serraggio !
     
  4. Arvid

    Arvid Formula Junior
    Silver Subscribed

    May 28, 2012
    668
    Norway
    Full Name:
    Arvid Andersson
    Steve, I spoke to Dedo earlier today. He needs confirmation that the given torque figures for #21 are correct. The manual states 85Nm for #25 (M12) and 48Nm for #21 (M8). His mechanic who works on his engine raised the question as he thinks this is too high a torque for the M8 bolt.

    I have not found any other figures than the ones given in the WSM.

    Regards,
    Arvid
     
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  5. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    25,037
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    Arvid -- I think you swapped #21 (which seems to be the larger M12) with the #25 (M8) in your second sentence, but I get your point. I have no direct data/information for that torque for #25 (M8), but the 48 Nm does seem highish. For me (without any other information), a lot would depend on how stud #23 is mounted into the block:

    If it's just an M8 male thread stud going directly into the (soft) Aluminum casting = that would concern me that, at a torque of 48 Nm, the stud would just pull out of the Aluminum.

    If it's an M8 male thread going into a steel heli-coil, or better yet a steel time-sert, in the Aluminum casting = that could support a higher torque on the #25 M8 nut.

    Another possibility is that the stud #23 could be a stepped stud -- M8 on the end using nut #25, but a larger M10 or M12 size going into the Aluminum casting = that could also support a high torque on the #25 M8 nut.

    Just some random discussion, and looking to learning what Dedo discovers. Dedo's post in Italiano (translated perfectly into English for me, and) indicates that he may have an information source inside F at Maranello.
     
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  6. Arvid

    Arvid Formula Junior
    Silver Subscribed

    May 28, 2012
    668
    Norway
    Full Name:
    Arvid Andersson
    Yes,it's the #25 - I did manage to swap the numbers around... I tried searching the net for the 365GTC4 WSM but didn't find it. That would be a great comparison for torque reference.

    Given this is a 12.9 bolt standard torque settings ranges from 40-45Nm on different charts and in those figures there is always a safety margin. It could well be Ferrari opted for a few extra Nm so therefore another WSM would be very useful for comparison as it's not the first time they misprint info in their manuals.

    Dedo has enviable contacts so I'm sure he will come up with the correct numbers.
     
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  7. dedo tanzi

    dedo tanzi Karting

    Dec 16, 2013
    52
    Lugano - SUISSE
    Full Name:
    DEDO - Alfredo
    Dear Friends STEVE and ARVID ... Thanks for the help !:):):)

    You have understood exactly my problem, Monday I will have a precise answer from friends in FERRARI ... In any case, these data for the tightening of the nut for a small M 8, I seem really exaggerated !!!:oops::oops::oops::oops::oops::oops:
     
  8. rovexienus

    rovexienus Formula Junior
    Silver Subscribed

    Jun 10, 2010
    562
    Sainte Colombe, France (near Lyon)
    Full Name:
    Jean-Michel Savary
    I have a copy of the 365 GTC/4 repair instructions manual in English (1983 by Angello Wallace), here is what it says for the engine assembly after overhaul:

    "Install the crankshaft on the cylinder block, and the lower end caps should be fitting with their respective main bearings half shells. Tighten the 12mm diameter nuts to 8.3 Kgm (60 Ft.lb.) and the 8mm diameter nuts to 4.8 Kgm (34 FT.lb.). After all the nuts have been tightened, the crankshaft should rotate freely without applying force."
     
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  9. Arvid

    Arvid Formula Junior
    Silver Subscribed

    May 28, 2012
    668
    Norway
    Full Name:
    Arvid Andersson
    Thank You Jean-Michel.

    Two different WSM states the same torque - that should be good enough. Dedo also got his answer today - from one in Ferrari Classiche - who also says 4.8 kg.
     
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  10. dedo tanzi

    dedo tanzi Karting

    Dec 16, 2013
    52
    Lugano - SUISSE
    Full Name:
    DEDO - Alfredo
    [QUOTE = "rovexienus, post: 146341413, member: 93069"] Ho una copia del manuale di istruzioni di riparazione 365 GTC / 4 in inglese (1983 di Angello Wallace), ecco cosa dice per il gruppo motore dopo la revisione:

    "Installare l'albero motore sul blocco cilindri e i cappucci terminali inferiori devono essere montati con i rispettivi semigusci dei cuscinetti principali. Serrare i dadi da 12 mm di diametro a 8.3 Kgm (60 Ft.lb.) ei dadi da 8 mm di diametro a 4.8 Kgm (34 FT.lb.). Dopo che tutti i dadi sono stati serrati, l'albero motore dovrebbe ruotare liberamente senza applicare forza. "[/ QUOTE]
     
  11. dedo tanzi

    dedo tanzi Karting

    Dec 16, 2013
    52
    Lugano - SUISSE
    Full Name:
    DEDO - Alfredo
    Grazie....perfetto..

    Idem per il manuale della 400, motore F101....
    Ma il solo manuale stampato, è' del 1985, il mio motore e' un 02.1978....
    I prigionieri del banco...M8, erano in ferro....poi li hanno cambiati !!!!

    Adesso sostituisco almeno i dadi......

    GRAZIE !!!!!!!
     

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