Model PA Spark Retard

[Bill James]

I have also tried to find an answer to this problem. As you know there is very little in the way of factory manuals for our 31 PA's. I can find instructions on how to "time" the engine, but nothing on how to adjust the vacuum advance. When the engine is off, I would think the distributor would be in the retarded position for starting, then when started the vacuum would turn it to the proper position to run. That makes sense to me, but this unit is adjustable, and like you, I haven't been able to find any instructions. ??? Hey Guys, couple old shade tree mech's out here needs some help :-\

[R WILLIAMS]

I am trying to get a clear understanding of how the spark retard works on the 1931 Model PA.? I have the general understanding that its purpose is to retard the spark when the car is idling, but? I am primarily interested in learning to how to make sure mine is working correctly.? Thanks.