One quick check of the centrifugal advance is to grab the distributor rotor and try to turn it clockwise. It should move freely, and return to its original position from spring pressure, without any hesitation or stickiness. The weights and springs are located under the breaker plate and they're prone to get rusty or sticky. Out of sight, out of mind- - - -until a problem develops! Since the vacuum advance moves the whole distributor housing, it's easy to see if it's working. Centrifugal, not so much!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!