Carb overflow??

Discussion in 'The Garage' started by Irish John, Feb 20, 2013.

  1. Irish John

    Irish John Been here awhile

    Joined:
    Mar 30, 2008
    Oddometer:
    235
    Location:
    Lawrence, KS but I'd rather be in Ireland
    Trying to figure out a problem with my GF's DR200. Symptoms are after she puts the bike up, the gas overflows via the breather tube into the airbox and out on the garage flow. The tank has a vacum petcock which I replaced but apparently it did not fix the problem as when you pull off the fuel line gas just runs out regardless of the position of the petcock (there is no off position).

    Suggestions?
    #1
  2. Irish John

    Irish John Been here awhile

    Joined:
    Mar 30, 2008
    Oddometer:
    235
    Location:
    Lawrence, KS but I'd rather be in Ireland
    I don't think the petcock is broken. I am beginning to think it may be a problem in the carb, as in bad float, stuck jet or ???
    #2
  3. Andyinhilo

    Andyinhilo Long timer

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    If the petcock is working correctly it will flow when the motor is shut off only if the valve is in the "Prime" position. Therefore, you have a petcock problem.

    You also have a carb problem: one or more; stuck float, bad/dirty float needle or seat, bad float valve o-ring.

    You see, if the carb float system is working properly, the fuel won't overflow, even if the petcock flows fuel constantly. The petcock exists to prevent that overflow possibility.
    #3
  4. Irish John

    Irish John Been here awhile

    Joined:
    Mar 30, 2008
    Oddometer:
    235
    Location:
    Lawrence, KS but I'd rather be in Ireland
    Thanks for the help. I pulled the carb and it was very dirty. Also replaced the petcock with an on off version I found. We have a snow day tomorrow so I'll have lots of time tomorrow to piddle with it.
    #4
  5. LuciferMutt

    LuciferMutt Rides slow bike slow

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    Aug 19, 2008
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    Location:
    New(er) Mexico
    Bad needle valve/seat/needle spring/float/etc. Something is causing the needle to not seal correctly. As mentioned, even with NO petcock, a properly functioning carb should not overflow.

    Since you replaced the petcock with a simple on/off version, make sure you plug the vacuum port that went to the original unit.
    #5