Yep,
Thems the ones
It is a loop from the grounding bolt to the on - off switch and back to the kill tab.
Every time the magnets pass by the coil it should throw a spark, regardless of the position of the timing key
If the key is broken the spark will just happen at the wrong time.
Inside the coil is a ship that replaces to old points and the chips go bad .
Because the values of the resistor in the chip are unknown you can not test the primary windings
SO they are a works or trash item .