1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Engine Balancing

Discussion in 'Engine Building' started by klyph, Oct 18, 2006.

  1. klyph

    klyph Dismember

    Joined:
    Aug 14, 2006
    Messages:
    6,333
    Likes Received:
    253
    Location:
    North Pole, AK
    So i got the unorthodox PS/AC eliminating underdrive crank pulley, and the guy at the machine shop says i need to have the engine spun balanced since the crank pulley is "part of the engines balancing". I thought they balanced the engine by adding weights to the flywheel, but he indicated that the holes that circumferate the crank pulley have something to do with the engine balancing. If this is the case then how can they call this underdrive pulley a "bolt on performance part" if you gotta rebalance ur engine to make it work. If anyone knows whether i actually need to spin balance my engine to put this pulley on, please enlighten me, because i would rather not as it is quite expensive. Thanks.
  2. klyph

    klyph Dismember

    Joined:
    Aug 14, 2006
    Messages:
    6,333
    Likes Received:
    253
    Location:
    North Pole, AK
    Come on, i posted this last night, i expected an answer by morning. :mad: Bump.
  3. lsvtec

    lsvtec GNU/Linux Evangelist

    Joined:
    Sep 30, 2002
    Messages:
    5,453
    Likes Received:
    3
    Location:
    Greater Portland, OR
    It is part of the rotating assembly and IIRC the unothrodox pulley does not have a harmonic balancer so if it isn't balanced properly it will vibrate like crazy. It might be balanced from the factory, but I wouldn't trust it. IMO you should have it all balanced.
  4. klyph

    klyph Dismember

    Joined:
    Aug 14, 2006
    Messages:
    6,333
    Likes Received:
    253
    Location:
    North Pole, AK
    Ok, I'll get it balanced. At least now i can justify installing a lighter flywheel! :D

Share This Page