My gy6 150cc won't stay running
 

I just bought a go kart with a 150cc GY6 motor in it.
I replaced piston and rings and had the carb completely gone
Through the only way I can get it started and running is to put
My hand over the intake and feather the incoming air it did the
Same thing before I had the carb done and piston and rings done.
Once it's running it seams to run fine until I take my hand away
From the intake. Any suggestions.

Check for vacuum leaks. Make sure intake is tight. while engine is running spray some starter fluid around intake and engine side of carb. If engine revs up then you have a leak. That's a good place to start. Also may check the air fuel mixture screw, make sure its not screwed all the way in.

Thanks I will try that

Agree with the above mentioned ..if nothing check ur auto choke that its working...Eddie.