Ut-o...
After bad mouthing Optima for a while, I found out I have Optima 34M's which are start batteries, not deep cycle. I had someone check them out for me but never did so on my own. This was the 1st year I ever had them taken out, since new 3 years ago I left them in the boat all Winter with the charger pulled in most of the time (charger regulates charge, not an old style overcharger).
I may or may not have had an alternator go bad because of this, apparently that is one of the things having the wrong batteries does.
Just ordered 4 Sears Platinum PM-2 34M's. These 34M's meet Mercurys standards, the Optima 34M's do NOT, only the 31M's do.