"Bubbles" in the line can be a sign of a problem, or just a little residual fuel foam - it would take someone with experience to see it first-hand to tell the difference, however, the fact that fuel is spurting out of the carb AND you're getting a hydrolic lock tells me that the bubbles have little to do with it.

It sounds like you are running very rich (Too much fuel in the mixture)

Close the needle valve completely and open it about 1 1/2 turns. Prime the engine by adding a few drops of fuel directly into the carb and start it. If it runs and dies (with no fuel spurting out of the carb), open the needle valve another 1/4 turn and repeat as necessary