Here is a picture of metal part that blocks the secondary barrel. You can see that one of the choke butterflies is black (being used) and the other one closest to the valve cover is like new and not being used.

If you look inside of the carburetor top when the throttle lever is wide open (MOTOR OFF), both throttle plates should be working

If the one next to the valve cover is not, then you have the block still in place like in the picture.Loosen the bolt a little and turn the metal part 90 degrees out or remove it. You may have to spray carburetor cleaner on the parts to get them to work good again because they havenot been working for many years

Thanks, Gary.