When I rotate the prop hub slowly, when the magnet passes under the pickup I do not get a spark at the spark plug. If I rotate the prop hub quickly, it will spark. Should I be getting a spark regardless of rotation speed?

The reason I ask, is that I am having a difficult time getting this motor to start and run consistently. I have replaced the ignition (with another one from 3W), the magnet and the carburetor. I also tried a new pickup, but it does not work as well as the old one does. Now I'm wondering if I might have a timing issue, but it is difficult to see where the timing is set, if I have to rotate the prop hub quickly past the pickup.

This engine is a 15 year old 3W-60K (side intake) that has sat up for 12 or 13 years and now I am trying to use it again.

Any help would be greatly appreciated.