My guesstimate;mooseheadm5 wrote:I am not 100% certain on this, so I will ask. Is the coil secondary is actually wound around the primary several dozen times and not in a single run? i.e., does the wire get wound from one end of the bar to the other, then back and forth to make the many many winds of wire needed? I think so. It cannot possibly be one layer, as in the diagrammatic representation, the cutaway view shows that. If the wire gets wound around several times why can it not jump from one part of the coil secondary to another part of the coil secondary? That would be easier than jumping all the way past the coil primary to the ground lug then through the frame to the engine jumping the gap and coming back to the coil secondary. Ideas?
1..Because the tension enabling it to actually make a spark
is between the two ends of the secondary wiring,
let's say, for the sake of argument: the first and the 989th.(fictive number of windings)
Not between the first and the second, or the second and the 98th,
or the 98th and the 456th,
or what ever.
That would explain why it doesn't jump 'internally'
from x'th sec. coil-winding to y'th sec. coil winding
Now why doesn't it jump from one end of
sec. winding through the insulation-->to core-->jump again through insulation
-->to other end of the sec. winding
2..Current will always chose the easiest way
in terms of resistance.
Not necessarily co-related to distance.
In case of both plugs present:
It's easier to go via the leads and frame
and jump two plug with a tiny o,6mm gap
than jumping from the start of the winding through a thick insulation
and onto the metal core,
and then back again through the insulation yet again to reach the 'last' winding
(Not the plug-leads, nor the engine/frame
represent any noticeable resistance)
In case of one plug missing:
it has no choice,
it can only complete the circuit by
jumping as described above
through the insulation to the core
(but in this situation only one 'jump')
having been deprived the 'easy' way via the (second) plug.
According to what Nixon says
that's exactly what happens.