RE: How do 3W ignitions work?
Okay, 3D. . short and sweet, you SHOULD be able to rock the hub back forth under the crank pickup and get a spark. . period. I do this with every ignition I have and it FIRES. If it will not fire, on a consistent basis, by doing the "rock across the top" test, but WILL spark when spun FAST with a drill, you have either a bad pickup coil or magnet.
Best way to check the pickup coil is with an Ohmmeter. I just checked 4 3W pickups and 2 DA pickups.
The 4 3W pickups ohmed at : 275, 245, 238, and 285 ohms . . .the Two DA pickups ohmed at 245 and 315 ohms. Since both pickups will fire off either ignition (DA or 3W, merely change the connector and observe polarity) yours should fall within this range of about 240-325 ohms. If your pickup is outside that range by a significant amount, sayy., . below 200 or above 400 ohms, I'd get it replaced.
To check the magnet in the hub, try to hang a hobby knife from it, using the blade of the knife. If the Knife will hang, it's good, if not, it's bad. . period.
If these two components pass these tests, you more than likely have a bad ignition box.
Not exactly rocket science, but it works.