>>Sounds electrical, like the coil still has some voltage fed to it.
The
alternator, while it is still spinning, can potentially (!) feed some
current to the coil with the ignition off. But with the relative
resistances of the lamp and the coil this should only result in a very
small
voltage across the coil, insufficient to maintain a spark (otherwise
they
would *all* run on.<<snip>>
I disagree. This problem is very common in '77s not because of a wiring
fault but because of an alternator problem. The original alternator's
voltage regulator protected against current feedback through the
ignition light (and the ignition relay & coil), but once you change the
alternator or regulator, you run the risk of introducing this problem
unless the regulator is exactly the same as the original one which was
installed. Since it is virtually impossible to order a regulator which
meets the OEM spec. for the '77 MY alternator, it makes more sense to
install the diode in the ignition light circuit. I modified mine 2
years ago and have not had a problem since.
Rich P.
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