What can cause a motor to just STOP?

Project motor is a 1986 Mercury 75hp 2-stroke. Serial A932083. It sat untouched for at least 6 years. I've got it started and running and now I'm replacing the many gummed-up and dry-rotted things as I find them. I'm enjoying the challenge.

Last week on a run test, humming along, it suddenly missed once or twice, then shut off as if I'd pulled the key. All 12v stuff shut off too, momentarily, then came back. Motor would turn over but not restart. After 30 minutes, it did restart. I couldn't find any obvious broken or loose wiring, but I found some loose and missing ground straps, and replaced the rectifier because I had a new one.

Yesterday it happened again. 15 minutes or so into a run-test, the motor missed, lurched, then shut off. This time, nothing happens when I turn the key. 12v accessories work, the battery is strong, and the electric choke DOES click when I push in the key, but no response from the starter.

My plan is a couple days from now to replace the starter solenoid, the stator, and the trigger, again mainly because I have the parts. But based on what I described above, what else should I be looking at?

If the stator & trigger are bad, would the motor just abruptly stop like that?

No response from the starter might have to do with the nuetral start switch.-----The stopping of the motor may be due to a bad connection / grounded out wiring.----

Maybe the ignition key/switch is bad seen it happen before. Stator/trigger of course would have nothing to do with not cranking over, or total loss of 12v accessories.