I believe that wire is grounded all the time. That's the one you have to disconnect to do a continuity check across the points.
OM, Isn't the wire supposed to be grounded to the case, but when you lift it, the points should be making and breaking the connection to ground on the other end of the primary winding in the coil.
Once you lift the wire, and the points are open, you shouldn't have any further connection to the case, and a fairly low resistance through the coil primary circuit to the points. When the points close, you should have almost the same low resistance through the primary, the points and to the case.
the resistance through the coil secondary (spark output terminal to ground) should be a much higher value. K ohms on most mags.
Are you sure the points aren't gapped almost too wide or sticking when they get hot?
the condenser could also be bad. They're a lot cheaper than the coil.
Jim
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