Update:
With the somewhat colder weather kicking in, and now with the time change, my usage has gone up, and the voltage under load is dropping into the 11's well before I goto bed, and I am waking upto ~11.7 with 11.5 minimums recorded with ~60 A/h removed from the batteries.( 2 group 27's, 115A/h each)
Nothing is not working properly at these voltages. They are still accepting 60 to 90 amps when I start the engine and bring them into the alternator circuit, but their voltage does climb higher quicker under such current than before.
I can tell that when they are fully charged and I have all 3 batteries cranking the starter, it cranks much slower than just a few months ago.
I'm just wondering how long I am going to push these. I think they are perhaps teetering on the edge of a cliff. As I type they are at 12.1 under a 7.8 amp load @ 30a/h from full, and the alternator was just feeding them 90 minutes ago.
My Wally world dc-27 engine battery is due for replacement too at 7.5 years old.
Thinking bout replacing all 3, at once, with smaller/ lower capacity AGM's, cause I've had a lot of work lately, and watering( lack of) has been my primary battery killer over the last 5 years.
Considering just leaving a future 3 in parallel always with the option to disconnect the engine battery if/when I start drawing them into the starter "click" realm, which honestly, has not ever been an issue, not since I've gotten solar.
