Continuous spark

Anyone have thoughts on what could be causing continuous spark to lead 4, nothing to 1, nothing to 2 &3? completely baffled on this one. I always hate to jump to conclusion, but after tracing out wiring, blown ic ignitor seems only logical.
Did top end rebuild, went by the book, timing is dead on.
Start throwing ideas out there.

You might have a couple of problems. If you have spark on four, but not on one, then the spark is shorting to ground somewhere, otherwise you'd have no spark on either one, and it might be an internal short in the coil.
I would check the igniter ground, and if it was good then I'd try a different igniter.

If not already done, would test again with brand new spark plugs per factory specs.

The secondary loop must form a complete circuit for either plug to fire.
If one plug is firing and the other plug isn't firing, the circuit is being completed otherwise than via spark on the non-firing plug, which might happen with conductivity through a non-firing plug, short in the plug wire, or dark witchcraft.

















Good Fortune!

I vote for Dark Witchcraft, that would explain a lot of things :laugh:

It was dark witchcraft that put a barely visble nick in my points wire insulation that was arcing to frame creating that circuit. Thanks for the ideas guys. Have strong spark now to all 4. Now just have to get rid of this snow and sub zero temps

Patton wrote: If not already done, would test again with brand new spark plugs per factory specs.

The secondary loop must form a complete circuit for either plug to fire.
If one plug is firing and the other plug isn't firing, the circuit is being completed otherwise than via spark on the non-firing plug, which might happen with conductivity through a non-firing plug, short in the plug wire, or dark witchcraft.

Good Fortune!

One more possible short: inside the coil (transformer) when one end of the high voltage winding arcs down to ground internally.