Need help with an old Zuma carb

Discussion in 'Battle Scooters' started by STANIMAL, Nov 30, 2012.

  1. STANIMAL

    STANIMAL SUPPORT THE SECOND

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    I have an old Zuma that was sitting for five years. I went through the carb , replaced the pilot , needle and float . Also replaced the vacuum operated petcock . It starts and idles for a few moments , then dies , as if the bowl is running out of fuel .

    Does the air filter assembly need to be mounted ? I know some engines need it in place to run right . I have been in side the carb several times . All the orifices seem to be clean and flowing air . Any thoughts ?
    #1
  2. kiznile

    kiznile Scooter Commuter

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    I dont know the zuma specifically, but a lot of these vacuum operated fuel pumps need vacuum...check to see how your fuel pump operates..Just a shot in the dark
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  3. MODNROD

    MODNROD Decisions, decisions

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    If it's been sitting for 5 years, then it's likely the passageways in the carby are partially blocked by oxidation and/or varnish and crud, even if they look clean to the eye on first inspection.
    A full strip down and soak in cleaner will do it wonders.
    Same for the vacuum tap, maybe even more so. Fuel evaporates and leaves really stubborn varnishes.
    #3
  4. STANIMAL

    STANIMAL SUPPORT THE SECOND

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    The vacuum petcock is new and the carb has been cleaned , soaked and cleaned about a half dozen times . Like I said , every hole is flowing air . There must be something I am over looking .
    #4
  5. tbonestone

    tbonestone Been here awhile

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    Just for kicks, did you put the air box on yet? Try it and see if that helps. I always put the bike together fully then test run and tune.
    #5
  6. allstateclub

    allstateclub Adventurer

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    A few years ago I bought a hydrostatic cleaning gizmo from Harbor Freight. Cost was about $45-$50. I totally strip the carbs down, clean everything with carb cleaner, blow them dry with a pressure hose, then throw them into the hydrostatic cleaner that's filled with water. I was amazed at the stuff that came vibrating out of all those little holes. I've even vibrated the parts with solvent in the machine (NOT recommended by the maker). They seem to work a lot better without taking them off and trying to clean them again, then repeat again and again.
    #6
  7. STANIMAL

    STANIMAL SUPPORT THE SECOND

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    That's what I am thinking. I had a few bikes over the years that had to be tuned like that.
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  8. STANIMAL

    STANIMAL SUPPORT THE SECOND

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    Sonic cleaner , I should get one anyway.
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  9. hayasakiman

    hayasakiman Been here awhile

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    Did you remove the blocking plug and idle mixture control before cleaning?
    I'm not so sure but I think Zuma has that as well.
    #9