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Flooding

Discussion in 'Hangout Lounge' started by xjpensacola, Aug 21, 2013.

  1. xjpensacola

    xjpensacola Member

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    I just got a call from a mechanic that has had my XJ550R for over a month. He was to clean and adjust the carburetors on the bike. He specializes in the old bikes and prides himself on be a carburetor expert. He is giving up. I took it to him because I had unsuccessful in tuning the carbs and the bike was burning rich. He cleaned the carbs, checked floats, and balanced the carbs but no matter what he does the bike continues to run rich. He says it starts but within the first minute it will start to blow out black smoke. The bike had had some bigger jets in it but he ordered and installed the stock jets. He is not going to charge me but I don't know what to do next. Does anyone have any ideas what could be causing this if it is not the carbs? He says the compression is good and he has checked a few other items. Help
     
    xjpensacola, Aug 21, 2013
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  2. xjpensacola

    xjpensacola Member

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    Forgot, Its a 1982 SECA
     
    xjpensacola, Aug 21, 2013
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  3. ryevans21

    ryevans21 Member

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    -air filter modifications
    -Valve clearances not in spec
    -float levels not properly set (need to "wet-set")

    those are the major ones that come to mind that a "carb expert" may not always consider
     
    ryevans21, Aug 21, 2013
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  4. xjpensacola

    xjpensacola Member

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    It checked the float levels on the bench and he feels that they are OK.
    It has the original air box and standard air filter on it. Would the exhaust valves being too tight cause the bike to run rich?
     
    xjpensacola, Aug 21, 2013
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  5. bigfitz52

    bigfitz52 Well-Known Member Premium Member

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    Not necessarily, however the valves do need to be in spec before the carbs can be synchronized.

    "Checking the float levels on the bench" and "feeling that they are OK" is NOT the same thing as WET-SETTING (or at least wet-verifying) them. This is a very critical adjustment and can drastically affect how the bike runs. Especially since the spec for the Mikunis on the 550s has a tolerance of +/- 1MM.

    The guy is giving up because he is not the "expert" he claims to be. If he were, he wouldn't be trying to "balance" carbs on an engine that needs its valves adjusted. Valves come first.

    IN ORDER:

    -Valves in spec.
    -Carbs zestfully clean and pass the "clunk test."
    -Float levels WET SET to spec.
    -Accurate bench sync performed
    -Running vacuum sync with YICS blocked.
    -Final mixture tuning as needed.

    If this "expert" tries to tell you any different in regard to any of these items or the order they need to be performed in, then all he's doing is proving to you that HE DOESN'T KNOW WHAT HE'S TALKING ABOUT.

    Which is honestly not a surprise. He obviously doesn't have a service manual for the bike.
     
    bigfitz52, Aug 21, 2013
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