cappy208
Guru
I have a battery issue. Stumped. Last year I was having generator fuel issues. While on the phone with the Generator Rep He mentioned that during cranking it sounded like i had weak batteries. (ain't the live video chat great!) So i replaced the batteries (4 6V golfcart) with new Interstate batteries. One 800 cranking battery and one 700 extended hour battery.
The cranking (start) battery is fine. The combiner always brings it back to 13.8V. The extended (house battery) is always weak. It never gets above 12 V. It dies during use from head use, water pump, or chart plotter use (even while underway, with engine running full speed.)
Today I went down to the boat, installed a identical crank battery in place of the extended hour battery. (thinking dissimilar batteries were an issue) no difference. Then I swapped the combiner leads from one battery to the other. No difference. I'm amazed that the combiner wasn't the problem. The changed leads still charge the start battery to full quickly and the house battery barely gets charged.
So my quandry is: what to look for before I throw in the towel and call a marine electrician and blow a boatbuck or two to fix it?
The cranking (start) battery is fine. The combiner always brings it back to 13.8V. The extended (house battery) is always weak. It never gets above 12 V. It dies during use from head use, water pump, or chart plotter use (even while underway, with engine running full speed.)
Today I went down to the boat, installed a identical crank battery in place of the extended hour battery. (thinking dissimilar batteries were an issue) no difference. Then I swapped the combiner leads from one battery to the other. No difference. I'm amazed that the combiner wasn't the problem. The changed leads still charge the start battery to full quickly and the house battery barely gets charged.
So my quandry is: what to look for before I throw in the towel and call a marine electrician and blow a boatbuck or two to fix it?
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