2005 22v Battery Charging Problems

[red0522v]

I have an after market dual battery set up and have a charging issue. The alternator is new. The batteries are new as well. When I first start the boat the volts are above 13. But as soon as the alarm stops (a couple of seconds after the engine starts) the volts drop to about 11. When underway the volts go up to about 12.5 and drop back to about 11 at idle. I can rev the engine in neutral and the volts go up to 12.5,but always drop back at idle. If I don't trickle charge the batteries in between use they get low enough where boat starting is labored and I'm concerned about getting stranded.
I own a digital volt meter and am reasonably mechanically inclined but very little electrical knowledge. Would really appreciate if anyone has a good step by step trouble shooting guide for charging systems.

[25cents]

I had a similar problem and ultimately was stranded one day. Crazy thing was that is was just a loose wire that wasn't completely connecting. It was like a $8 fix. Not sure if that is your issue, but i would recommend checking every cable connected to your batteries and switch.

[Z1Fan]

I agree with 25 , but I would also make sure it's wired properly can you tell us , how's it's wired. And what was all installed ?

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[chpthril]

I would start by ignoring what the helm gauge reads and use your volt meter to verify the alternator output AT the alt, and the switch posts, at the batteries and finally at the helm. You could easily have a single charging issue, or 2 separate problems such as poor connection at the helm cause a low reading on the gauge and a parasitic draw when the boat is stored.

[red0522v]

I would start by ignoring what the helm gauge reads and use your volt meter to verify the alternator output AT the alt, and the switch posts, at the batteries and finally at the helm. You could easily have a single charging issue, or 2 separate problems such as poor connection at the helm cause a low reading on the gauge and a parasitic draw when the boat is stored.

Thanks for the quick reply's. As far as what is installed, the second battery is connected to the stereo. Although the batteries appear to be wired together. No isolator I've seen in other posts. I'll do he tests Chpthril suggests and look for loose connections and post the results. Will be a week or so before we're out on the boat again.

[chpthril]

Is there a dual bank battery switch in there, are both the batteries wired together as one?

[red0522v]

Is there a dual bank battery switch in there, are both the batteries wired together as one?

Appears to me they are wired together as one. I don't see any type of switch or isolator.

[red0522v]

Appears to me they are wired together as one. I don't see any type of switch or isolator.

OK, was able to do a bit of testing this evening. Best I can tell the batteries are wired together in parallel. Battery one is the cranking battery and battery 2 runs the stereo. I ran the boat for about 20 minutes and took the following voltages;
Idle - Alt 13.2, Bat 1 13.0, Bat2 13.0, gauge 11.2
2000 rpm - Alt 14.5, Bat 1 14.1, Bat 2 14.0, gauge 12.0
so I'm guessing there is some kind of problem at the dash? with the ignition switch? Any suggestions for trouble shooting from this point?
Thanks!

[chpthril]

Best I can tell the batteries are wired together in parallel. Battery one is the cranking battery and battery 2 runs the stereo

You basically, and electrically, have one battery doing all the duties. When 2 or more batteries are wired together, they become one, regardless of what cables are connected to which battery, the cables linking them, make them a single battery. I would suggest a simple dual battery switch to separate them.

so I'm guessing there is some kind of problem at the dash? with the ignition switch? Any suggestions for trouble shooting from this point?

Could be a bad gauge, bad cable or poor connection anywhere between the battery and gauge. Start at the back of the gauge and use the volt meter and work backwards until you find the voltage drop. This may require extending your meters leads back to the battery. This is necessary in order determine if the voltage is on the B+ or B- feeding the helm.

[red0522v]

You basically, and electrically, have one battery doing all the duties. When 2 or more batteries are wired together, they become one, regardless of what cables are connected to which battery, the cables linking them, make them a single battery. I would suggest a simple dual battery switch to separate them.



Could be a bad gauge, bad cable or poor connection anywhere between the battery and gauge. Start at the back of the gauge and use the volt meter and work backwards until you find the voltage drop. This may require extending your meters leads back to the battery. This is necessary in order determine if the voltage is on the B+ or B- feeding the helm.

Thanks for the quick response. Regarding the switch are you recommending an isolator or a manual switch. Could you recommend a specific brand and model? I will start the 'hunt' this weekend. Is there an easy way to tell and measure if there is a parasitic draw when the boat is stored?

[chpthril]

A manual switch is simple and effective, just takes a little discipline. I use the Blue Sea 9001E switch. Well worth the cost diff over the Perko brand. For a semi-auto switch with ACR, I like the Blue Sea ACR and Dual circuit switch.

[red0522v]

A manual switch is simple and effective, just takes a little discipline. I use the Blue Sea 9001E switch. Well worth the cost diff over the Perko brand. For a semi-auto switch with ACR, I like the Blue Sea ACR and Dual circuit switch.

OK, was able to do some more testing and isolated the problem to the perfect pass. I noticed when starting the engine that the volts on the dash gauge dropped from 13.5 to 11 after the perfect pass beeped (indicating the perfect pass was powered). I then disconnected the power at the perfect pass module and had normal (13.5) volts at the gauge. So now I need to find the issue in the perfect pass wiring! At least I know where to look. Thanks for all the help. I'll post when I find the root cause.

[chpthril]

I still feel its the B+ or B- feeding the helm or the gauge.

[TWOhunter]

I bought a 2005 22V in January and it was equipped with dual batteries. It has a switch to turn it to off, 1, 2, or 1 & 2. I can also trickle-charge it while in storage.

It gives me some peace of mind as I run it on 1 or 2 while on the lake in case I need to switch over to the other battery.