timing McCormick-Deering 10-20

[rwaynew]

When timing a 1928 McCormick-Deering 10-20 should the spark advance on the mag be in the bottom position or upper position

 

[Oldiron29]

usually set in advance to time, than it can be retarded to start. I have had to go a notch one way or the other to get the sweet spot for best running. oldiron29

 

[Fritz Maurer]

The spark advance has nothing to do with the timing procedure. The impulse coupling should trip at TDC as per marks on the flywheel. It will always trip in the same place regardless of the position of the manual spark advance.