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OMG what have I done to my carb??

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So I’ve already rebuilt the carb myself as part of full engine rebuild and that went great.

 

I guess I couldn’t leave well enough alone.

 

Jetting proved to be too rich after breakin, so I innocently took the throttlebody assembly out, removed the needle jet, and moved the clip position one position higher in atrempt to lean things out a bit.

 

Then I put it back together just as I had taken it apart. It was a very simple operation.

 

So when I went to turn the gas on for the first time, it’s spewing gasoline out at a high rate out of all three of the overflow hoses!!

 

I obviously need to take it apart again, but I honestly have no idea how things could’ve gone so sideways for such a simple change of the needle jet clip position. Looking for a bit of guidance here between now and the time I’ll need to find to take it apart again. Video:

 

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I am guessing your float needle is stuck wide open or perhaps fell out when you disassembled the carb.

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Thanks, but the thing is, all I did was take  off the cap and remove the throttle valve assembly so I could remove the needle and adjust the clip position for one setting leaner. I didn’t do anything inside the carb assembly itself, or touch the float assembly or float valve.

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Thanks --- I'll try that.  Something's clearly stuck open and that's probably it.  I guess these ol' carbs can be sticky/fickle bastards at times.  I'm just in such denial since I had JUST rebuilt the thing with a kit and everything was working so great prior to such a seemingly minor/simple change as I embark down the jetting road.

I also found this post/thread which has several good suggestions/ideas and I'll start with rotating the carb after loosening both sides, drain/remove the float bowl, inspect, check float/needle/valve assembly, do the 'blow through' test as described in that post, and go from there.  https://thumpertalk.com/forums/topic/1262420-keihin-carb-on-200xcw-fuel-goes-directly-to-overflow/

 

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2 hours ago, Dcummins69 said:

It’s stuck open, try taping on side of carb or pull float bowl off again.

Yes, that usually works for me too, no need to dismantle anything

 

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OK thanks everybody. So in the end it had to be a stuck float valve, that somehow managed to get into the stuck position merely by my taking the carb out, moving cap and throttle valve assembly so I could move the needle clip position up one notch as a first effort to remediate a rich jetting condition.

One test that I found pretty cool/valuable was to blow into the fuel line while the carb was right side up and expect air to blow through fine, which it does normally. Then when you flip the carburetor upside down, you should not be able to blow air through. If you can, that equates to a problem with the float mechanism.

I couldn’t, so I reattached the gas tank / line with the carburetor right side up, slowly turned on the gas, and... not a drop. Hooray.

Lesson learned, that whenever I muck with the carb these things can be kind of fickle as regards the float mechanism overall, so best to perform that test whenever pulling the carb for any reason, and/or try rapping on the bottom of the carburetor next time if it’s stuck to the point where that overflow condition exists.

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I actually do that “blow test” every time I rebuild a carb before reinstalling it. Has saved me from having a pull the carb back off many times.

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