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Discussion Starter · #1 ·
I bought Larry's manual and a bunch of new parts and cleaned and rebuilt my carbs. They were leaking fuel out of the drain tubes before I rebuilt them. And now they're REALLY leaking. I'd say 2 drips per second.



I've since pulled them apart 2 more times, reset the floats to 15.5mm and replaced the float needles. They still drip constantly. Even when the bikes running.



They don't appear to be dripping anywhere but the drain tubes. The left side specifically.



I checked the brass tubes in the bowls for cracks during the rebuild and they both looked clean.



The bike runs pretty well, but has some trouble firing up when it's not warmed up. I usually have to give it some throttle to get it going.



What else should I be checking that could cause this?
 

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Did you install a fuel filter?



Try turning your fuel tap on and open the float bowl drain screws one at a time, allow to drain into a jar while tapping the float bowl with a screwdriver handle or similar. This might dislodge any crap from the FNV and flush it from the float bowl.



Often works for me.
 

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As Phreak says and also sometimes they can take a little while to bed-in so go for a good Urban ride where you are varying road conditions/Gear changes a lot




PS

Did you fit an in-line filter?
 

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Discussion Starter · #4 ·
I should add, I did notice a tiny tiny chunk missing from one of the floats. I wish I remembered which side it was on. I'd say it was maybe a 1mm chunk missing. I'm not sure if this would effect anything?
 

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Discussion Starter · #5 ·
I bought an inline filter, but it's too big. I'll go buy some extra tubing so I can run it, and try the tapping trick.



I would think after cleaning them out 3 times, this would have gotten any debris out though.



On the plus side, I've cut my carb dismounting time in half.
 

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Sometimes the overflow tube can be split so small that it is very hard to see. If you have the carbs off, just fill the bowl with fuel and see if there is a leak from the drain. If that is the case, clean the tube with 400 paper and solder the crack. 5 minute project. You can use water to test, but fuel has a lower surface tension than water and may seep through when water doesn't.



You can also use the trick of attaching a clear tube to the drain and route it up beside the float bowl. A properly adjusted and functioning float will allow the level of the fuel to rise to just below the the top of the float bowl in the clear tube.
 

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It could be leaking past the drain screw,,have you taken them out and cleaned and inspected them?



Shep,,,hairspray????
 

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I should add, I did notice a tiny tiny chunk missing from one of the floats. I wish I remembered which side it was on. I'd say it was maybe a 1mm chunk missing. I'm not sure if this would effect anything?


is it possible that the float is not floating, has been perforated, and its not shutting off the fuel supply? a chunk missing?
 
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