How long did it set between carb rebuild and running it?
Did you run the same gas that was in tank? Was tank cleaned?
Did carb job include replacing old fuel lines, primer bulb, etc?
Take a fuel sample in a clear container and get back to us with what that looks like. Squeeze primer bulb to get a little in a jar.
A proper fuel system job when you have dirty carbs is drain tank and make sure its clean, new fuel lines if you are unsure they are alcohol resistant, all new filters, complete tear down, clean and replace of parts in carbs as needed.