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512TR belt tensioner bolt torque

Discussion in 'Technical Q&A' started by JIMBO, Aug 30, 2020.

  1. JIMBO

    JIMBO Formula 3
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    Oct 31, 2003
    1,282
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    Jim DeRespino
    The 512TR WSM shows a torque spec of 100 Nm for the 19 mm head cam pulley bolts, but does not specify a torque for the 19 mm head belt tensioner bolts. I think 40 Nm is correct, but I cannot verify this. Any help?
    Thanks.
     
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  3. yelcab

    yelcab F1 World Champ
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    Nov 29, 2001
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    Mitchell Le
    I would go 50 Nm.
     
  4. wmuno

    wmuno Karting
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    Dec 24, 2007
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    Torque values are based on the thread size. For coarse threads, zinc plated, grade 8.8 the values are: M8=24; M10=48; M12=83 NMs. You can print a very nice table from Fastener Mart.
     
  5. Ferrari Tech

    Ferrari Tech Formula Junior

    Mar 5, 2010
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    Wade Williams
    WSM says 55 Nm for tensioner bolt, and 98 Nm for cam pulley bolts.
     
  6. yelcab

    yelcab F1 World Champ
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    That is ... Maximum torque value that can be applied safely to the fastener at the sizes and material strength used. That is not the recommended torque value for the application. The M12 bolt (17mm head) used for the same tensioner pulley on the timing belt is spec for 50Nm torque, much lower than 83Nm from that table.
     
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  8. JIMBO

    JIMBO Formula 3
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    Jim DeRespino
    Thanks. I thought 40 ft lb (55 Nm) for the tensioner bolts was correct, I just could not verify in the WSM.
     
  9. yelcab

    yelcab F1 World Champ
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    Nov 29, 2001
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    Mitchell Le
    You said 40 Nm, not ft-lbs. That is not correct at all.
     
  10. wmuno

    wmuno Karting
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    Dec 24, 2007
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    Bill Muno
    If a value is given in the WSM, then by all means use that value. Torque values vary by the application and the strength of the bolt, Absent any stated value, the values in the torque table can be safely used.
     
  11. JIMBO

    JIMBO Formula 3
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    Oct 31, 2003
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    Jim DeRespino
    You are correct. I meant 40 ft lb.
     
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