Engine Trouble carb leaking tons of fuel - float bowl problem I think

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Nate888

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my motor wouldn't start even though I had spark. I suspected something with the carb - maybe something was clogging the carb. so I completely disassembled and cleaned it, then did my best to put it back together correctly, but I'm not 100% I got everything right cuz now it runs, but it runs kinda weak, and when the petcock is open, it pours gas right out on the ground.

it looks to me like the float bowl valve (terminology?) is stuck open and over filling the bowl with gas till it comes pouring out the vent holes

I've been able to drive by manually opening the petcock about one second for every 5 sec that it's off to control fuel level in the float bowl. obviously that's getting old, so does anybody have any tips or resources to help me get it sorted out and back working again?
 
How about the gasket? If the gas level is naturally above the level where the gasket rests then it could leak if it's either installed wrong, damaged, or plain missing.

Are you using the Dellorto style clone? The "banjo" fuel line connection can be very temperamental, taking them apart can result in difficulty making a good seal and that will leak.

The only way you could have damaged the float is by dropping a wrench on it or purposely went out of your way to ruin it. The actual needle to say could be damaged if cleaned wrong, it's got a small rubber tip usually, touching it can supposedly damage it, so I try not to touch the end, or harsh cleaners can damage the rubber. I've had an issue recently with my sisters bike, turned out her tip was simply missing, who knows how that happened, put a different needle valve on and presto no problem.

Take the carb off, and poke around a bit, start wherever the fuel begins on the carb, work your way through and stop if you make it to the intake manifold because if you do you've missed something.
 
holy crap, I bet I answered my own question! I bet i stopped up the float assembly with locktite, which i hastily applied cuz the little rod - that the float pivots on - seemed prone to slipping out either side

let me check this hypothesis
 
How about the gasket? If the gas level is naturally above the level where the gasket rests then it could leak if it's either installed wrong, damaged, or plain missing.

Are you using the Dellorto style clone? The "banjo" fuel line connection can be very temperamental, taking them apart can result in difficulty making a good seal and that will leak.

The only way you could have damaged the float is by dropping a wrench on it or purposely went out of your way to ruin it. The actual needle to say could be damaged if cleaned wrong, it's got a small rubber tip usually, touching it can supposedly damage it, so I try not to touch the end, or harsh cleaners can damage the rubber. I've had an issue recently with my sisters bike, turned out her tip was simply missing, who knows how that happened, put a different needle valve on and presto no problem.

Take the carb off, and poke around a bit, start wherever the fuel begins on the carb, work your way through and stop if you make it to the intake manifold because if you do you've missed something.
thank you.. if it turns out it's not just a matter of scraping away a little glue, I'll try going by your tips next. the carb is whichever one comes with the gt 80 full kit from gas bike. net

is there anywhere with schematics or videos of these carbs so I can get a better grasp on their terminology and the details of how they work?
 
The float post will never fall out when the bowl is attached, so as long as it's installed right and assembled carefully the float bowl 'walls' kind of sit right up along the sides where the pin slips in, the stop it from comming out far enough for a problem. If you assemble the carb upside down, with the throttle cable end facing the ground, then put the float bowl on in that position, you'll be able to turn it over while holding it together and install the screws (should they be on top) that hold the bowl on without the internals getting crazy.

Carb parts On This site, http://motoredbikes.com/threads/nt-carburetor-assembly-pics.4854/

Photo Of Carb Please?
 
20161115_020625.jpg
here the carb, sorry it's sideways

I think the errant Locktite was the problem

at one point I'd put it back together without the little screw on the side and it still ran, although I'd maybe stretched nylons over it for air filtering, so that might've helped: I would think the opening would cut down on its ability to suck in fuel, but if it had 2 layers of fine stretchy fabric, damp with gasoline, it would seal better than nothing and contribute to atomizing fuel into the mix
 

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