The needle valve wont allow fuel to come into the carberator

that check valve will be the needle and seat operated by the float
check for dirt or hair in the valve not allowing it to shut of the fuel properly

check that the needle and seat are not stuck together or there is not a blockage in the little filter before the needle and seat

is/was the check engine light on??as far as no fuel try spraying some carberator cleaner in
the throtle body to see if it helps starting.

If you have gas coming out of the top of the carburetor then you could have either a bad float, a stuck float or a bad needle and seat, all of which are inside the carburetor. The float rises with the level of fuel and shuts off the incoming fuel by pushing the needle valve against the seat thus stopping any more fuel from entering the carburetor until the fuel level drops slightly at which time the needle moves slightly away from the seat and allows more fuel to enter again. You could also have a piece of crud that has gotten between the needle and seat which will prevent the valve from fully closing but that's pretty rare. You will probably need to have the carburetor cleaned, inspected, and have a repair kit installed to fix the problem.

An easy way is to remove the air cleaner off the carb, and give the top of the carb a couple sharp taps with a small hammer or a heavy screwdriver.. sometimes you can simply loosen the needle valve and float up this way.
You may need to take the top of the carb off. The float and needle valve work together to stop the flow of fuel into the carb. You want to check to see if the float is not full of fuel.. if it is , then it's got a leak and should be replaced... spray the needle valve and seat with carb cleaner spray to remove any build up.. And as long as the carb bowl is exposed, clean the basin out as well.

It sounds like a stuck or worn needle in the carburettor. It is like the ball valve in your toilet. If it is you will need to replace it and the seat. It is inside the carburettor and allows the right amount of fuel into the fuel bowl. Over time the it wears and the needle does not sit properly in the seat so it leaks. Some times it wont close properly if it becomes gunked up. If the needle sticks open the carburettor floods and nothing works properly. It is a simple enough fix to do yourself but a good mechanic should be able to sort it in about half an hour.

Uncouple the fuel line coming from the pump at the carburetor, place a clean can under the line, and have someone operate the starter--you should have fuel shoot from the line in spurts as the engine turns. If it does, then the entry port on the carburetor is plugged. Remove the float assembly and pull out the float needle valve. Hook the fuel line back to the carburetor and try the starter again, there should be fuel pumping into the float bowl. If not, check to see if there is a filter on the fuel inlet path that may be plugged. If no filter, remove the float needle seat to see if something is blocking the fuel passage. If all else fails, use compressed air to blow backwards through the needle seat (remove the fuel line again). Hope some of this helps!

The float needle valve and seat inside the carburetor float bowl needs replacing or has debris trapped in the seat. If the valve does not seat completely it will allow all the fuel in the bowl to flow into the cylinder. The valve stops the flow of fuel once the bowl is full. When it is not seating properly the fuel will continue to flow. This is not a good thing as the fuel will enter the crankcase and mix with the oil. This will eventually damage the engine bearings. You can purchase a needle valve and seat assembly to repair it. Here is what a typical unit looks like.

Sounds like the needle valve and seat are leaking in both. The needle valve shuts off the fuel and holds it in the float reservoir. If the valve does not seat properly it allows the fuel to drain out overnight. You may need to overhaul the carburetors. You also may have a pin hole in the float. You can check that when you open it up.

Remove the coveer to the carberator. Pour some gas into the carberator. If it runs you are not getting any gas to the carberator. It may be the fuel pump.