Installed Two New Carbs and the Blower Won't Stay Running

I have never run into this before - I cleaned the carburetor and that didn't work so I ordered a new one and installed it. It started but would not rev up or stay running. Like it was starving for gas. I thought the carburetor was faulty so I ordered a replacement and installed it but had the same outcome. I have installed new gas lines, new gas filter, new air filter, new spark plug and new gasket. I'm stumped. And I did check to make sure I had the the two gas lines on correctly. When I pump the primer bulb, gas comes up and the return goes back to the tank. I know it's old but it ran great until a week ago after adding gas stabilizer. Any suggestions would be greatly appreciated!

Thanks,

Bill