Well, after analized your question, I came out with only one thing in mind; Ignition Switch.
The ignition switch its the only device that controls the "power" of the engine and electrical components that can be turn on just with the key in "on" position.
Could be that the "solder" on the ignition switch or the contacts are defective.
As a random issue (Vibration. Heat. Etc) that trigger the "cut-out" .
Make the ignition switch check it good.
Let us know and good Luck!
BTW Thanks a lot for your Donation!
We appreciate that !
Wednesday, October 31st, 2007 AT 8:41 PM