[Bob Putnam]

Keith,

You have a starter solenoid in your system, either mounted directly on your starter, or interposed between the starter and the battery. We mount ours right on the firewall. I suspect that it might be your problem.

Follow the power (+) wire from the battery to the starter. The solenoid will be in there somewhere, with another smaller wire (or two) connected to it. One of the smaller wires comes from the ignition switch. The next time you have the problem, disconnect the small wire(s) from the solenoid. If the starter still runs, the problem is definitely the solenoid.