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Leaking keihin float bowl drain

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I have a 2008 ktm sx-f 250 and my carb (keihin fcr-mx) has started leaking out of the carb bowl drain valve and overflow and won't start (I assume from flooding).

I assume the float isn't shutting off fuel but I feel like I've exhausted all those options. Any better ideas or possibilities?

-I have checked float level (perfect)

-replaced float needle

-needle seat is permanent not the screw in variety, but didn't appear to be damaged.

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Also check to make sure your fuel line between tank and carb is not breaking down on the inside. Mine was on my 2009, and it was causing tiny bits of rubber to be deposited into the bowl.

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Yeah I though about trying to polish the seat since it isn't removable but I also don't want a bunch of polishing compound working it's way into my carb by accident, don't know if I have a choice though...
Fuel line is fine and zero debris in carb

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The most common cause of gas overflow is a STICKING float needle. Corrosion gets into the cavity it sits in, and it gets 'stuck'. 

Polish the cavity and needle body.

Another issue can be the oring below the seat. They corrode and leak.

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4 minutes ago, andykinnen said:

Yeah I though about trying to polish the seat since it isn't removable but I also don't want a bunch of polishing compound working it's way into my carb by accident, don't know if I have a choice though...
Fuel line is fine and zero debris in carb

Just use a small amount of mothers on a q-tip like in the video, then spray out with carb cleaner and compressed air.

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Another issue can be the oring below the seat. They corrode and leak.


It has the press in version of the seat, I doubt there's an oring under that right?

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