Problem with Minn Kota MK 460PC Charger

[rpr]

The one bank I have my starting battery on will not charge past 50%. The other 3 banks that have my trolling batteries in them all charge up to 100%.

So I assumed (dumb me) that my 7 year old Sears DieHard PM1 was finally on the way out and I purchased a very expensive new starting battery, but the charger is still doing the same thing. The old PM1 battery is reading 12.9V.

Anybody experienced this with their charger? Any ideas?

[CatFan]

The one bank I have my starting battery on will not charge past 50%. The other 3 banks that have my trolling batteries in them all charge up to 100%.

So I assumed (dumb me) that my 7 year old Sears DieHard PM1 was finally on the way out and I purchased a very expensive new starting battery, but the charger is still doing the same thing. The old PM1 battery is reading 12.9V.

Anybody experienced this with their charger? Any ideas?

Swap the charger bank leads from the cranking battery with another battery.

[rpr]

It will take me a while before I can find the time to do that, my starting battery is no where near my other batteries. Just out of curiosity, would you guys consider 12.9V to be a full charge? My other batteries seem to get up to around 13.4V.

[catdude28]

After surface charge has dissipated, full charge for a PM 1/Odyssey is 12.84 volts. I wait for at least 12 hours off the charger to measure battery voltage

[rpr]

After ~18 hours I’m still at 12.93V on the old PM-1. So the battery is apparently good (?) and the MK 460PC is apparently fully charging the battery, but it’s only reading 50% on the LEDs.

Any idea what would cause this?

[CatFan]

The charger determines charge state by how much current is being drawn from it. Anything in the boat like a pimp or light could fool the charger.

You need to distinguish between voltages just off the charger and resting voltage. All batteries should read a little over 13v when they are fully charged and either just off the charger or with the charger still on. Once they rest they’ll get to their actual full charge voltage

[rpr]

Thanks, nothing is turned on in the boat when I leave it charging so I don’t think that’s it. I just remembered that a prior rigger did extend the length of the charging cable that runs from the charger to this battery. It’s a fairly long run. I think he used 14 AWG wire. If that wire/cable has deteriorated that could slow the rate of charge, correct?

[Jspell]

Is your charger set for agm/ flooded /gel and which type battery do you have connected to it?

[rpr]

I have the Batteries Plus X2Power SLI31AGMDPM and the charger is set to AGM, as it was for the DieHard PM-1.

[Jspell]

Thanks, nothing is turned on in the boat when I leave it charging so I don’t think that’s it. I just remembered that a prior rigger did extend the length of the charging cable that runs from the charger to this battery. It’s a fairly long run. I think he used 14 AWG wire. If that wire/cable has deteriorated that could slow the rate of charge, correct?

I would check these connections where he spliced into to lengthen the cable...Then the fuse holder for corrosion etc.....

[rpr]

I didn’t get to do any troubleshooting today but I was able to check on it. After ~32 hours, it was blinking green on the 100% light. If I understand correctly, this means it’s in maintenance mode, somewhere above 90% charged but still less than 100%. The old PM-1 never got past 50%. So apparently my old battery was on the way out, but it should not be taking this long to charge. All the other banks were solid green.

I’ll check all the connections on that bank when time permits. Thanks for all the feedback.