I am running a pair of 229 V6 165 HP motors. My house bank is supposed to charge from the Stb. Engine. Didn’t appear to be charging so I got by, by switching to “All” and having the Port engine alternator charge both starter battery bank, as well as the house bank. Trouble is that it couldn’t really keep up with demand, so I am troubleshooting the Stb alternator/charging system.
It appears that the original alternator wires have been replaced. Tough to trace because those wires disappear into the spaghetti! My question is this:
1) on this 2-wire alternator (Prestolite 8RG2069), what volts/amps does the exciter wire require? I have researched and think that it requires a keyed 12v power source, available only when the engine is running, (via oil pressure-activated switch). I have tested and the switch seems to work fine. It connects when oil pressure is up.
2) when I connected a jumpered 12v powers source direct to the exciter terminal, the brand new alternator appears to be putting out 19-19Volts. Why?
3) Am I right in assuming that the output (charging)terminal on this alternator is wired direct to the starboard (house) battery bank?
I have replaced both the House and the starter batteries. Now I also have a new alternator, and I want to make sure everything charges as it should. I want to isolate the house bank when cruising so I don’t get stranded, and I want full charging when under way. I am considering running new wires, and just want to make sure that the exciter circuit gets the right volts/amps. This subject is confusing. I have read that the exciter circuit needs a small resistor/diode/bulb to knock down the input volts... anyone who understands this system, please enlighten me!
It appears that the original alternator wires have been replaced. Tough to trace because those wires disappear into the spaghetti! My question is this:
1) on this 2-wire alternator (Prestolite 8RG2069), what volts/amps does the exciter wire require? I have researched and think that it requires a keyed 12v power source, available only when the engine is running, (via oil pressure-activated switch). I have tested and the switch seems to work fine. It connects when oil pressure is up.
2) when I connected a jumpered 12v powers source direct to the exciter terminal, the brand new alternator appears to be putting out 19-19Volts. Why?
3) Am I right in assuming that the output (charging)terminal on this alternator is wired direct to the starboard (house) battery bank?
I have replaced both the House and the starter batteries. Now I also have a new alternator, and I want to make sure everything charges as it should. I want to isolate the house bank when cruising so I don’t get stranded, and I want full charging when under way. I am considering running new wires, and just want to make sure that the exciter circuit gets the right volts/amps. This subject is confusing. I have read that the exciter circuit needs a small resistor/diode/bulb to knock down the input volts... anyone who understands this system, please enlighten me!
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