smoking guns

Discussion in 'Engine, Fuel and Exhaust' started by MrbigMINI, Sep 6, 2010.

  1. MrbigMINI

    MrbigMINI Member

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    I have a 77 superglide, I has a SS easy e carb on it and when it is at idle, "warm or cold" it starts smoking. But as soon as you give it a little gas it stops smoking. And if im on the interstate and slow down to an idle it will bellow out smoke and kill every mosquito for 100 yards. But again, as soon is i turn the throttle just a little it clears up. What could be the cause? bad float?
     
  2. chopper75

    chopper75 Member

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    sounds good if it kills mosquitos
     
  3. TQuentin1

    TQuentin1 Well-Known Member Staff Member Moderator

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    Hmmm. Smoking is not good. Usually a sign that the bike is burning oil. Not a fuel issue.

    Suggest doing a compression test and leak-down test to try and get a read on the condition of the rings and valve guides.

    Compression Testing - Harley Davidson Community

    TQ
     
  4. Breeze3at

    Breeze3at Well-Known Member

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    What color is the smoke? White/gray/bluish is engine oil. Black is fuel, over rich.
     
  5. MrbigMINI

    MrbigMINI Member

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    its a white blueish color smoke oil smoke. Do you know what PSI the compression should be around. I can already tell you mine is low. i just checked it and the front cylinder is at 80psi max, and the rear made it to around 70psi. I just bought the bike, and the guy told me had had just rebuilt the engine. sooo....... what should i do now? lol.
     
  6. TQuentin1

    TQuentin1 Well-Known Member Staff Member Moderator

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    Just as in "just before you bought it"? With no miles on the rebuild? In that case, you may just need to do the ring break in procedure. See here:

    Engine Break In For New Motors - Harley Davidson Community

    Those compression numbers are WAY low assuming they were done right.

    If the bike was run for a few thousand miles since the rebuild, and those compression numbers are right, try squirting about an ounce of oil in the cylinder and do the compression tests again. If you get a big jump in compression, there is your answer!!

    Let us know.

    TQ
     
  7. Jack Klarich

    Jack Klarich Expert Member

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    HMMMM, some shovels never had valve seals from the factory, does yours?:s
     
  8. fisherman124

    fisherman124 Active Member

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    i have an 80 and neighbor has a 74 and we dont have that happening both with S&S check out like stated above
     
  9. fin_676

    fin_676 Experienced Member Staff Member Moderator Contributor

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    Remember when doing a compression test to hold the throttle wide open or you will get a low reading as the air has to get in there before it can be compressed

    Brian