The pinch clamp should be tight enough that there's a definite stop at the end of the vacuum advance movement. It shouldn't turn after that. Crank it down a bit more if it still turns.
Kevin 1951 Chevy 3100 work truck Follow this saga in Project Journal Photos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together.