The vacuum advance needs to be connected to a ported outlet...The vacuum advance unit is designed to give the spark a quick catch up just as the throttle plates open .Then the mechanical weights take over...On an inline you can see if the lever is moving or not while reving the engine a little..Momojets have a lot of different outlets for emissions that can be pretty dead at different times..A vacuum gauge is a handy tool..Use it to find an outlet that shows a vacuum reading just as the throttle plates open..Make sure the line to the distributer has no leaks..Connect the line..rev the engine a little..If there is no movement the diaphragm is probably leaking..Chevy six distributers were not the best of design so it is wise to pull them out and check for bushing wear and to make sure the advance weights are good.. Al...
