Gas Tank leaking out through Carburetor

S

Shika_Usstan

New Member
So since I am a "Newbie" I get to make all sorts of posts about my troubles. Occasionally my gas tank will completely drain out through my carburetor. It was quit a surprise the first time I came out and all the gas and oil had spilled all over my back porch. At first I thought it happened when the engine was choked out and then never restarted but I have done that in a long time. And I kinda would like it to stop. . . I've got in the habit of turning the gas valve off before I walk away so if it does leak its not very much of my tank.

So the question what do I do!?!.bf.
 
Your float could also be getting stuck. Smooth out the bowl with fine sand paper and make sure that the carb is sitting level.
 
My first question would be have you checked your fuel petcock? Some of them do not shut the fuel off when the lever is 90 degrees to the fuel line. Turn the petcock off then disconnect the fuel line from the carb. Is the fuel still running out of the tank? If so move the lever until it stops then mark and remember where the lever needs to be to actually stop the flow of fuel. If you're unable to stop the flow with the petcock then replace it. Let us know what you find and DO NOT run your engine on pure carburetor cleaner. That's a good way to score a piston and cylinder walls.
Tom
 
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With the petcock closed, take the gas line off the petcock. Check to make sure it is not still letting some fuel through. Move the lever on the petcock until it really is shut off. Use a "sharpie" or scribe a line in the metal to mark where "off" really is. When you turn off the fuel put it on that line. This has pretty much solved my leaking issues with the stock petcock.
 
leaking out all the fuel when not in use is signs of a float needle sticking or not set right. You are using a fuel filter? wallyworld sells a fuel filter in the lawn and garden area it clear with a paper element about $5.00 or less. check out my carb tear down should get you on track for the carb if not let me know I might need to do some pictures and text on setting the float.
you can look here for info on the carb
http://motorbicycling.com/f39/motorized-bicycle-carburetor-install-rebuild-302.html
 
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Okay so if I arrange what everyone has said . . . If the petcock is off and I'm still leaking everything I have 2 problems the petcock "off" is not completely off and the carb float is sticking. If the bike doesn't leak when the petcock is off its just a sticky float.

Since I think the "off" works . . . I need to make sure the carb is sitting level, sand out the inside of the bowl so nothing on the sides could affect it and make sure the line is being filtered so crap doesn't get stuck in there and cause the float to get stuck in unwanted positions. . . Is that right?
 
I think either you have some crud under the floats needle allowing it to stick open or the float is not adjusted quite right have not seen the float stick on the float bowl yet. It usually has a good finish in the inside I'd hold off on sanding anything inside the float bowl, unless you see a big booger in it.

most times it is crud sticking in the floats needle just needs a cleaning do not poke the opening with anything or sand the needle on the float, compressed air or carb cleaner works best and with the carb upside down and the float bowl off you can see if the float is setting level which it should be. check out my post on the carb too.
there is a link on #6 - 2 posts up.
Norman
 
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Check most of the philips heads on the carb as well as tighten/seal up the intake nozzle.(carefully)
Both our kits have drain plugs , and a couple of the screws have shotty washers.
They tend to leak if not tight, and can come loose enough to leak easily.
 
After much consideration I believe I have found the problem. . .However this is not for certain. . . The float is used to push on the tickler, is it not? So My kick stand is not tall enough to keep the bike upright so if the bike leans on the kick stand the float tips and the side the tickler is on bends down and the tickler is left untouched. . . So it keeps adding more and more gas to try and get the float up to the right height thus causing it to leak out of the air intake hole and soak my air filter.
 
get a double kickstand(i plan on making my own).
i think the tickler button pushes the float down to let more gas in.
even if you fix it,the airfilter will be wet from back splash of gas/oil and will be a few drops on edge of carb.i put a hose on the end of my carb and ran it to a airbox with filter,its really quiet like this.
 
I have noticed that the metal valve fingers that are in contact with the float sometimes are not bent correctly and they will make the float stick. You may want to check that the float moves freely. If it doesn't just bent the ends so that they don't bind on the float and then you have to re-bend the base of that part to make the bottom of the float is even with the bottom of the jet. Otherwise it is probably the needle valve isn't seating properly and you will have to re seat it. I read on here that you can put tooth paste on the needle and spin it in the valve to re-seat it. Make sure everything is really clean after words!
 
But what he said about his kickstand could be an issue. If bike is at too much of an angle, then maybe the float would not be able to push the needle valve closed. Just a thought.

Shika, try propping you're bike up on something so that it stays upright and see if this happens again. If not, problem solved, you need a better kickstand, preferably a center stand. If it does happen, then keep looking for an answer.
 
Oh, also: if this is happening when the fuel valve is OFF, then something is also wrong with the fuel valve. Others have said that, I just wanted to reiterate.
 
Check you float bowl gasket. Mine was leaking since the kit was new, I made a new one instead of ordering a new one and waiting for it to arrive. I made a post about how I did it, look for "Replacement gasket tip". Good luck!
 
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