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1976 non CV keihin 'butterfly" carburetor - Harley shovelhead

Discussion in 'Motorcycle Tech Talk' started by BigNick, Apr 23, 2018.

  1. BigNick

    BigNick New Member

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    I disassembled all the internals on my 1976 'non CV keihin carb' here. I soaked it over night and didn't realize the main nozzle comes off also. It has holes down the sides of the tube which need to be aimed a certain way. Can anyone tell me which way to turn that nozzle when I put carb back together? Thanks for the help. Big Nick
  2. bambidee

    bambidee Active Member

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    Not familiar with carb, when U say nozzle is it the booster that the airflow pulls the fuel from? If so the holes would be on the engine side not air cleaner side I would think. Any pics?
  3. BigNick

    BigNick New Member

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    This is the carb made to fit on a 1976 Harley shovelhead. The nozzle has a series of holes in it and it goes into the tube on carb that its leaning on in picture. Keihin carb carb nozzle.jpg
    Last edited: Apr 24, 2018
  4. bambidee

    bambidee Active Member

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    Am I correct that the main jet screws in and holds the tube in the well? If so I would call that an emulsion tube to break up the fuel. Most likely it just drops in with no rotation direction.
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  5. BigNick

    BigNick New Member

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    Yes thats the main jet which holds the main nozzle in. Some say it doesnt matter just drop it in and others say aim it toward the engine not the air filter. I dont really think there is much aiming on this setup. Thanks for your time. BN
  6. hotroadking

    hotroadking Super Moderator Staff Member

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    It won't matter, the part you want to be concerned about for
    direction is the pump jet orifice, it should hit the direct center of the back of the intake that sticks up into the middle of the intake opening of the carb.

    The part you show is the tube that the main jet is screwed into.
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  7. kenfuzed

    kenfuzed Administrator Staff Member

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    +1 what HRK and the others said. The emulsion tube doesn't have any specific orientation, just put it back in. If you soaked the carb make sure you removed the plug over the mixture screw and removed the packing (spring, washer, o-ring), otherwise the o-ring could have swelled inside. Soaking with the mixture screw removed allows you to get the air/idle mixture passages cleared. Just be sure to count the number of turns on the mixture screw when removing so you can set it back to original.
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  8. BigNick

    BigNick New Member

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    Kept the mixture screw info. (2 1/4 turns) I didn't take the pump jet orifice off, just left it on. Should it be removed and cleaned? I noticed last night the ball bearing in the bowl wasn't rattling and I couldn't get air to blow threw the orifice. I put the bowl back in the carb cleaner and its been soaking over night. Any cleaning suggestions or just blow it out with compressed air like I did before. I'm hoping I just didn't get the cleaner in that area the first time. Thanks
  9. hotroadking

    hotroadking Super Moderator Staff Member

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    Blow it out with compressed air, if you don't have a compressor get
    a can of compressed air for cleaning computers etc from an office supply
    or walmart.

    Don't try and remove the pump jet, leave it in, adjust it after you put it
    back together with the air cleaner off, twist throttle and see where the fuel
    spray hits, you can turn it with a pair of needle nose pliers, don't over stress it.

    When you go to put the idle air mix screw back in, seat it gently don't crank it
    in, you can damage the hole area it adjusts, just lightly get it to seat then back out.
  10. BigNick

    BigNick New Member

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    So your saying it should spray in the center of the butterfly if I am understanding you. I have air compressor. Thanks for the quick response.
  11. hotroadking

    hotroadking Super Moderator Staff Member

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    It should spray a stream straight to the middle of the back of the intake
    it should not spray direct on the butterfly that would be too high and would
    screw up the stream, it should shoot right past the needle into the center of the
    intake.
  12. hotroadking

    hotroadking Super Moderator Staff Member

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    The whole video isn't important, just that you see how the accel pump works at the beginning.

    Last edited: Apr 25, 2018
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  13. BigNick

    BigNick New Member

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    OK I understand now. I should have looked b4 I tore it down. Soaking again got the balls rolling around so that should be OK.
    The gas tank on the left side was rubbing the frame and the top of rocker box. I will space it off the rubs and use some type of rubber washer if I can get it to fit properly. You ever heard of using at least 1 rubber washer per connection to help prolong life of tanks?If so whats a good washer, or is that a waste of time. Thanks again.
  14. BigNick

    BigNick New Member

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    MVC-019S.JPG I am sending a pic of whats left of the non cv keihin rebuild kit. The only thing I cant find a place for is the small rubber gasket in the picture. Does jt look familiar to you. Thank you again. Big Nick
    Last edited: Apr 27, 2018
  15. bambidee

    bambidee Active Member

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    Maybe for the mixture screw?
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  16. BigNick

    BigNick New Member

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    I dont remember if any of the mixture screws had any O ring on it. The only screw I can be turning without removing the bowl is the low speed mixture screw. Its the right size for a mixture screw. I just dont remember taking one off. Hopefully someone that is more familiar with this carb will read this and straighten me out. Thanks for your help
  17. BigNick

    BigNick New Member

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    I have found that that washer fits on a 78-80 carb. Mine is a 1976. I assume the kit would work on both carbs. Thanks for yalls help, once again. Big Nick

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