Carb Help!

tdot23

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Hello,

I got a cf moto 500 with a mikuni carb bsr36. Currently when it runs, gas pours out of the overflow tube. I have taken it apart to check the floats, needle and seat. Everything moves freely and there is no debris in it. I took the floats out and tested it in water. Seems to float. I tested the needle i believe it is working. the rubber tip shows no sign of wear or damage. I also changed the seal on the seat. I have polished the inside of the seat also. I am stumped. I have also bent the tang on the float to close the needle valve much sooner. It did nothing. Machine runs fine, choke works fine. Any ideas? I was at it for a long time and not sure if there could be something else causing this.

thanks
 

JMCX

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It runs fine even though gas comes out the overflow? Have you tried removing the bowl, hold the float up with your finger and turn the gas on to see where the gas might be getting through?
 

tdot23

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yes it runs perfectly fine. no cant do that cause it only pours out while its running. i cant have it running with the carb off.
 

JMCX

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I missed the part that it only happens running. So it will be doing this and you can kill the engine and the overflowing stops? Are there separate vent lines that may be blocked?
 

tdot23

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there is only one hose and it goes back to the fuel pump. it is clear though. if i pinch the overflow hose it floods itself.
 

tdot23

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is it possible that the fuel pump has to much pressure and its forcing fuel by?
 

tdot23

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so i bent the tang on the floats a ton. i just thought i would try it. it slowed it down, so i bent it some more. the floats would barely move because of how much i adjusted it. machine runs fine and only a small amount of fuel comes out of overflow after a hard pull. Doesnt make sense to me but i guess it works. Solved for now!?

thanks
 
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