Chris,
Back to basics:
Current flows through the ignition coil, a magnetic field results, the points interrupt
the current flow at the proper time, the collapsing magnetic field attempts to maintain
the current flow and the result is a rapidly increasing voltage at the output of the coil.
This high voltage seeks a return path, this should be across the spark plug gap, through
the ground return.
In thinking a little bit about what you wrote it occured to me that you may have a voltage
leak somewhere downstream of the cap. If there is a bleed path then it is possible for
the output voltage of the coil to be reduced significantly - enough of a bleed path and
there will be no spark at the plug. Now if you put a spark gap at the cap, then the
collapsing magnetic field will result in a healthy high voltage. After this high voltage
is attained the current will jump the gap (in the distributor cap) and this high voltage
will be presented to both the bleed path and the spark plug gap (in parallel presumably).
This is all conjecture of course. I recall devices that were sold to do just this,
claimed that they would fire oil fouled spark plugs.
Your spark plugs are new aren't they ? If not try changing them for a new set and see if
that fixes it. Oil fouled sparkplugs result in the sparkplug insulator becoming covered
with carbon, which is a pretty good conductor. Could also be your plug wires, inspect
then for cracks, or run the engine at night with no lights around and look for a spark or
for a plasma glow.
Good luck,
-Roger
Chris Stephenson wrote:
>
>
> I guess my question really is why does it run correctly when I arc the
> spark and doesn't when I push the wire all the way in the cap -
> especially when I cleaned all surfaces. Does the rotor affect this? I
> have swapped several caps and several wire sets trying to diagnose.
> One thing that I also did which I did not think was related was
> replace my generator. I did this two days ago. Could this have any
> affect on the strength of the spark and cause this problem? I will
> test this theory tonight or tomorrow. If it runs fine after I push the
> wire in, I will conclude that I was not getting enough voltage (or
> amps - I am an financials consultant, not an electrical engineer so I
> do not know which will affect the spark). Your thoughts please.
>
> Chris
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