carb flooding

[HankReardon]

Gentlemen -

About two weeks ago, I posted several questions, and with your answers, I was able to fix every single problem that I asked about. Unfortunately, a new problem has arisen.

My Yamaha 200E trike seems to "leak" fuel into the (I am not a mechanic, excuse my lack of technical terms) air passageway (main tube going from the air cleaner, through the top part of the carb, into the cylinder).

I took my bike out for a great ride, and after about 5 minutes, it died on it. She ran great until it died. Once it died, it wouldn't even fire. To save time, instead of taking the carb off, I just popped the throttle off of the carb. The little hole where the throttle needle goes down had gas coming up out of it. it wasn't high pressure, but it was enough to get the passageway damp.

My needle nose assembly is brand new. I took the carb apart and by pressing up on the float, the flow of gas would shut off. The air equalization tube is clear. The float moves very easily on its own.

Any thoughts on this? I thought I had my trike in perfect working order, but this last problem baffles my mind.

Thank you in advance for any responses.

[chris200x]

Take the carb off and take it apart. clean it good with carb cleaner. making sure to blow out the jets. then reassemble. it only takes one little speck of dirt in there to clog it up.

[Rustytinhorn]

How old are the floats? It is possible that the floats could be collapsed or have lost their boyancy, so it doesn't shut off the gas flow at the correct level anymore causing it to flood.
Did you say the float needle valve was brand new? It could be worn or have a foreign object (piece of silt or sand) keeping it from closing all the way.
Just my two cents. Hope it helps.

Just another thought... after it dies, does the spark plug come out soaked and wet, carbon fouled, or dry and white?
Assuming it comes out wet, it is flooding. Maybe also check and make sure the air filter is clean and there are no obstructions in the air intake, (Papertowels, rags, mice, dog food, etc)
Something you could try is pulling the air cleaner off, and BRIEFLY try riding it without the cleaner and see if that cleans it up. (Such as one lap around the house or up and down the street once) Dont do it anywhere where there is any dust though.

Yes, if you could tell us what the plug looks like or could post a pic it would better help us to understand what the problem might be.
Hope some of this works for you.

[HankReardon]

the float appears to be fine. I worked on it some last night. The needle valve did catch a little, I doubted it was the problem, but I was able to adjust it (by rotating the inside piece) to a point where it didn't catch. The machine once again ran fine for about 5 minutes, or until I tried to let it just idle.

At that point it died, and the carb air passageway again looked to be wet.

I took the spark plug out, and it did not appear wet.

I did notice that it appeared to run more rough at low RPM's. Could it be something in the pilot jet? Is the tip of the jet suppose to above or below the gas level. Mine is most certainly below.

Something else that I thought was really odd: I drained the gas in the carb, but when I would close the drain screw, it kept leaking out until I took the throttle off. It almost seemed to me that there is some sort of pressure building up in there. Although the air tube is not blocked.

I'll try to take some pictures this weekend when I work on it.

To give you a better visual, imagine that you leave your carb as is, but unscrew the throttle cable. When you look into the hole, everything looks wet. Gas continues to leak out of the main jet into that chamber. Once the gas is shut off, it stops leaking.

[kwbyfrmhell]

take off your float and set it in a can of gas overnight, check the next day if it still floats, shake it next to your ear and listen for liquid. I have found sometimes floats will look fine but have a micro hole. Gas vapours can find their way in and collect. Sticking a float in water to check will not work because of the difference in viscosity