I know nothing about my electrical system. 1993 Rinker 300, repowered with 5.0 Mercruiser motors, 30amp Guest charger, and three batteries. I always thought the port and starboard batteries started the port and starboard motors, respectively, and the center battery was the house battery. Now, I'm not so sure.
Went to boat today and barely got one motor started. Turned over real slow but finally started. Tried the other motor; clicking from solenoid indicating low battery and the running motor died. The meter at the electrical panel shows 120v coming in, and 7.5v on the 12v side.
I checked voltage at each battery and got 12.1v at the port and starboard, and 7.5v on the center battery. I've tried to find an electrical schematic to no avail. A generic schematic indicates all three batteries are charged, through an isolator, by the charger or the alternator, which makes sense. But, will one bad battery cause problems to the remaining batteries? I did not change the battery switch positions because I don't know how everything is set up. I have one double switch and one single switch and have no idea how to isolate a particular battery. Can I get a quick education on the setups or does someone know the easy answer, i.e., can I change out the weakest battery and fix the problem? Or, could the problem be the charger?
Went to boat today and barely got one motor started. Turned over real slow but finally started. Tried the other motor; clicking from solenoid indicating low battery and the running motor died. The meter at the electrical panel shows 120v coming in, and 7.5v on the 12v side.
I checked voltage at each battery and got 12.1v at the port and starboard, and 7.5v on the center battery. I've tried to find an electrical schematic to no avail. A generic schematic indicates all three batteries are charged, through an isolator, by the charger or the alternator, which makes sense. But, will one bad battery cause problems to the remaining batteries? I did not change the battery switch positions because I don't know how everything is set up. I have one double switch and one single switch and have no idea how to isolate a particular battery. Can I get a quick education on the setups or does someone know the easy answer, i.e., can I change out the weakest battery and fix the problem? Or, could the problem be the charger?
