Johnson Outboard and dual battery systems with ACR

[egscharf]

I have a Johnson 112 (20 amp) rigged with a 2 battery blue seas add-a-battery system with an automatic charging relay. One battery is my house battery, and the other is for starting. The problem I've been having is that the house battery continuously loses charge and dies. This happens once every couple months, and I take my boat out nearly every weekend.

My guess is that because I generally slow troll (around 1000 RPM's) and only run wide open a few times throughout the day, the starting battery never exceeds 12.9 V, which I believe it has to in order to close the relay circuit and begin charging my house battery. Is this correct?

Should I just parallel wire my batteries using a 4 position selector switch? (Off, batt1, batt 2, 1+2)
I dont believe my charging system is the source of the issue as I had the same issue with my last engine I had on my boat and have recently repowered.

Thanks.

 

[SCduckhunter]

Re: Johnson Outboard and dual battery systems with ACR

Honestly i dont know tons on this stuff..however it seems that the motor would produce a low voltage trickle charge..
running/ trolling at low rpms would most likely produce a next to nothing charge..i am not familiar with the specs on output vs rpm....best solution would be to just throw house battery on a charger/ conditioner when you get home after a weekend or two of outings...also if you completly drain a battery alot of them are good anchors as they wont properly recharge and hold..just my .02?