[stackj]

Circuit breakers can surely be a problem. When I first got our Skymaster (17 years ago) we had problems with the main alternator bus breakers blowing. Everything would run fine for a while, then one of the mains would blow. Shortly after that, the other one would pop. There was just no way you could keep the alternators on line.

I finally purchased two new main breakers (35 amp as I recall), replaced the originals and the problem went away. Since that time, I have upgraded the alternators to the 60 amp units (The original were 38 amp) and, of course, have upgraded the wiring, breakers, etc. to support the higher current capability.

I gues the object of this reply (if there is one) is let you know that circuit breakers can weaken with age. The breakers are not that expensive and could save you some trouble. It does seem that you and your mechanic have most likely identified the real culprit with your voltage checks. I would expect that adjustment of those would eliminate the issue if you are simply having the electrical system shut down. The overvoltage system should not blow the field breaker when it activates. If the breaker is popping, I would suggest that you do both the regulator adjustments and replace the field breaker.

Good Luck and Blue Skies!