Keep the best magneto

Today Warren and I have compared the two magneto’s to find the one with the best spark. This is the one I am going to keep as an original magneto; running independently.

The other magneto, will undergo a bit of a rebuild:

  • I will still use the distributor.
  • I will still use the contactor.

But that’s where it finishes for generating the sparks. What I am doing is using a modern car ignition coil, that feeds into the magneto where the old coil used to feed into the distributor.┬áThe contactor will still be used but now it will switch the external ignition coil, using the battery as a power source.


What this means is I will have nice big sparks, see photo on the right of at least 10mm, even at the lowest engine speed, that’s while cranking the engine.
This ignition system relies on a battery though, but I have a battery already, so no extra weight.

The second real magneto is still there, generating nice sparks when running, so that’s my safety net.

As an interesting extra thing, Warren is going to try to make an alternator of the magneto I am rebuilding, so basically rewinding that coil you see just above, to generate a supply for the charging the 12V battery. It won’t be much, but I might as well use it.┬áThe same alternator signal can be used to produce my tachometer signal, using some electronics circuitry…


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