I updated my battery system in my 35' Outlaw from 2 batteries to 4 blue top optima's. I am getting low voltage alarms at WOT. I found the Starboard motor alternator was bad, so I replaced alternator and re-charged batteries and I am still getting voltage alarms at WOT.

Is it bad to have 4 blue top optima's for battery system. I have 2 on each motor and even with battery switches on BOTH, I still get alarms after about 30 mins of WOT.

I'm no electical expert but I'll take a stab at your problem. Just wondering if the alternators are not rated or capable of providing enough juice while charging two batteries vs one? The extra batteries will help power everything when the motors are shut off, but while running the alternators provide all the juice. Maybe they are drawing too much and not enough is going to the electronics. Also, the blue tops are the newer AGM sealed type batteries. Were the old batteries sealed as well or were they standard style? There is a difference in how AGM and Standard batteries respond to charging systems. If the system is not designed for sealed batteries, then they will not work properly. We ran into this problem with a battery charger/tender on a work vehicle. Put a Red Top battery in it and the charger system would auto default to a Standard style charge. You had to manually select the AGM charge option. Long story short, if the power went out then back on or if somebody did not switch it, we would have a dead truck despite being plugged into a charger system..