OK!! I have solved my problem. I am the cause of the problem.

I talked to Rickie this AM and he convinced me to test my new 36volt 100amp Skinny Water Marine battery circuit before I totally tore my boat apart. I did as Blake from Skinny Water had told me, I turned my trolling motor circuit Perko on with the trolling motor powered up. I put the negative lead from my VOM (volt/ohm meter) onto the negative post and the positive lead to a well grounded spot on my hull. With the VOM on 50 volts DC setting, the needle instantly went to 36 volts. OH CRAP!!!!

My boat was custom wired with 6 gauge marine wire. I had installed a 220Volt heavy duty twist lock receptacle and plug for my TM. A friend had talked me into this about 5 boats ago and I had NEVER had an issue until now. The plug had internally shorted out to ground and into the hull. As soon as I removed the plug from the hull, the voltage went to zero. I am now installing a Marinco 70 amp 36 volt plug and receptacle.

I feel sure this has been a short time thing. The Ultrex has lately done some unexplained things, like shutting off when I knew I have plenty of battery left. A new plug and receptacle along with an upgrade program on my Ultrex I Link and remote should solve my issues.

Thanks everybody for your help and encouragement. This had me scared big time. Hope my stupid mistake helps somebody else avoid it.

BTW, I used the term electrolysis in my title. This was NOT electrolysis as I now know after reading PAGES from any source I could find to solve this. This was stray voltage corrosion. Big difference.