If it is now revving harder that it was it is something you have done.
I would suggest that the diaphragm is not seated correctly. Can be fixed with the carb in place on the motor.
Unless you have removed the starter and that crank seal is no good now it has been disturbed.
Or if you have been wiggling and jiggling too much and the inlet manifold has cracked or come apart. I have seen that, the manifold is two bits of plastic stuck together and they can come apart.
