I appreciate all the input and my plan is set.
1. At some point I will install an Echo or similar regulator and change up my wiring configuration. I completely rewired the boat a couple of years ago adding new wiring, fuses and a breaker panel etc and took great care to try and do it right. This never came up so will fix that.
2. In the meantime I will just adjust how I function. I have an analog voltmeter which was starting to show roughly 12.2 values. I thought it was supposed to be up near 13 but did not pay it much mind. Never again. I am on a river and have a roughly 30 minute motor to get to the end of the channel. Going down the river will start/run off battery 1 and going up the river will start/run off battery 2. This way both batteries will get full attention for at least 30 minutes per trip. Until I get the regulator this is probably the best I can do.
I will also pay more attention to the batteries in the off season and bring them in to get tested. The last thing I want is to not be able to start my engine when I have to get back to my mooring against an outgoing tide. I have SeaTow but would rather not have to call them. I am also planning to get an electric trolling motor and battery for my dinghy which will serve as a nice backup if needed.
You will regret the things you did not do, more than the things you did.
Get out there!
Saco Bay, Maine
1971 Ericson 29