Dies then pukes petrol out of air box

[NickHous]

I am having an issue keeping my bike on. It idles for a minute then two. Then dies and pukes petrol out of Airbox

I clean the Carburetor and adjusted the float. With that done I find no change.

I replace the Fuel Pump Diaphragm, and find it is the same as new one.

I feel the last place to check is the Auto By-Start/Automatic Choke/Petrol.

If you have advice or another part you think I should examine please let me know.

I did a pressure check on both the Diaphragm and Float/and Needle, I find they work 100%

[scootergrisen]

You can test the fuel valve by removing the fuel hose from the carburetor and putting it in a fuel container.
Then remove the vacuum hose from the inlet manifold and there should only come fuel out the fuel hose when you suck on the vacuum hose.
When you stop the sucktion the fuel should also stop.

Remove the float and the float valve and check to see if the point of the value is good and if there are dirt down the hole. Blow air from the opposit hole so the dirt can come out. Check to see if there are petrol inside the float (its damaged).

You could remove the air filter and wipe the box clean and try running the engine without air filter and then see what hole the petrol comes out.

On 2 stroke engines this can happen if the value does not close properly so some of the pressure goes backwards.
You could try removing the air filter from the carburator and holding your hand or maybe a piece of papir there and see if the pressure goes backwards.