vacuum advance or timming issues

I got a chevy 350. Can get it running smooth, instant throttle. Turn the car off go to start it again & it runs rough & sounds like it's flooding with throttle. Mess with distributer again. sound good turn it off turn it back on & it goes back to sounding like crap & does that lowbing. Disconnect the vacuum advance. Adjust the distributer. Runs perfect full responsive throttle. Turn the car off. Start the car 10 seconds later & u have to start the process all over again. Does any one have an idea on what could be the problem.
Reconnected the vacuum advance after adjusting distributer & left it off. Both had the same results.

Sheared pin on the dizzy gear?

Many times on Delco dist with the advance weights in the top like on chev-----------the shaft doesn't get lubed and gets sticky--------can be stuck in the far advance and not start-backing it down will start but not rev, etc-remove rotor and twist the part that the springs weights are on and see if it rotates on shaft smooth/easy---------If you have to take it apart IIRC you must remove dist drive gear on bottom of dist and remove dist shaft so the advance unit can be taken off and cleaned up--- you might try some penetrating oil from the top but if you get too much oil in there it will be slung around in the cap causing miss fire-

Thanks for ur advice. It was was stuck. I swap the dist out with an accel I had another engine. Runs perfect now. Thanks again.