Charging problem

[78sharpshooter]

Volvo penta AQ225D and while running (idle to revving to 3000 rpm) the batteries are at 12.45 volts (measured with handheld voltmeter), the dash volt meter show 11 volts, and only once when I was running circles in mission bay did the dash volt meter suddenly go to 13-14 volt and I confirmed it with the handheld voltmeter. The red wire to the alternator shows the same voltage as the batteries, there are 2 black wires to the other post one from the engine block and the other from???, the third post on the alternator has a small wire connected to it labeled resistor. I have the seloc manual but in the interest of getting to the problem ASAP I am seeking help here. Should I pull it and take it to pepboys to test it?

[Dirtguy]

Sounds like there is a loose wire somewhere. Either side , grounds too. Dash gauge has bad connection also.
Sure! Take it to PB to eliminate the alt.

Then start a "volts drop" test for each section of wire in the circuit. That will pinpoint the bad connection/wire.
Have you done one before?
DG

[78sharpshooter]

I haven't but yesterday I read about those types of test where a large voltage drop indicates excessive resistance/bad connections. The resistor wire was feeding 8.8 volts and the connections appeared to be fine. So I took it to pepboys to run a test and the voltage regulator appears to be bad. The guy repeated the test 3 times and each time it was bad. The rectifier is fine so should I just replace the voltage regulator assuming that you can even though it is an integral voltage regulator? Or just buy a new one?

[piperca]

You can take it to an alternator repair facility and have it rebuilt. It'll be around a hundred bucks. Check with the shipyard for a referral.

[Alfred]

Take your alternator, starter, generators to Broadway auto electric in Lemon Grove and talk to Rick (Owner). I have twin volvo engines and the person I bought the boat from said he tried to find a similar problem. He said that the volvo electrical system has a tendenacy to have these kind of problems. My Starboard engine has a problem with showing 12 volts during a trip , then 12.5 and when I get home to wash the boat it shows charging at 13+. I also have problem with the water temp going up. Thought it was a overheat problem. Installed mechanical guages and temps are ok. The electric water temp gauge on the dash, sometimes goes over 200 but the mech. gauge stays in the correct temp. After a time the oil gauge started to go up and water temp at the same time. I can only do so much. If you have a gauge, that can be separated from the volvo system, you can eliminate if the problem is real.

[piperca]

I had this problem, too (twin AQ225Ds). The alternator was bad. I had it rebuilt and everything was fine. I found a battery cable that had broken at the connector, which added to the problem. I also had oil and water temp issues in the past. I changed the sensors and never had another problem. I really don't think these issues were Volvo Penta specific, just bad sensors, which you'll find with any manufacturer. I have a rebuilt alternator for sale, if you're interested ... PM me.

[78sharpshooter]

I just took the alternator to Brodings Battery Warehouse in La Mesa because the volvo penta store across from west marine reccommended them. Dave at Brodings got it fixed in quickly and I picked it up the next day and it is good to go. The sierra replacement alternator is $420!!!!!! I paid $65 to get this one fixed and I am ready for tomorrow.

[piperca]

Way to go! Yeah, I don't understand the cost on these alternators. I paid around $100 to have mine rebuilt. Now I'm in the midst of a repower, so I have a ton of parts for that engine ... don't hesitate to ask if you need something.

[Dirtguy]

I think that it's that tag, "MARINE" that makes it so expensive. I've been nagging that I don't understand why MARINE stuff is so expensive.

Great ideas and smart advice to get it done at an automotive repair shop!!

DG