Im having problems with my Terrova 80 loosing power if I run it for over 3 minutes on #5 (or higher) dial setting. It will beep and reset itself in 1-5 minutes. My boat is a 2000 Triton TR-19 with factory wires and I'm running 50 amp fuses. Minn Kota recommends 60 amp but my 50 never trips. I'm thinking it has 8 gauge wire but do I measure the diameter of the copper only without the insulation to determine wire gauge?

Thanks,
Bart