Charging AGMs- Dual Pro or Minn Kota

[rangerranger]

I have a 2016 Ranger Z520C with the original Dual Pro 4 bank charger. I am getting very poor life out of my AGM batteries and wondering if it could be related to my charger. I don’t think it should be the charger and I have always had good results with Dual Pro in the past.

My trolling batteries are Interstate group 31 AGMs. The first set lasted one year and were replaced under warranty. Exactly one year later the new ones are going bad. Interstate is replacing them again. I give them credit for honoring the warranty but they shouldn’t go bad so quickly and it is a PIA pulling them out and exchanging them.

My cranking battery is the group 31 X2 from Batteries Plus. It is 16 months old. It charges fine but now runs down very quickly during the day. It is down below12 volts in less than an hour with 2 graphs on. Yesterday I had to jump it by 11 am and we weren’t even running the livewells.

I use the boat year round. I plug the charger in immediately after each trip and leave it plugged in until the next trip. All banks show green by morning the day after using it.

So the question is whether the charger is poorly suited for these batteries or are the batteries just junk? I’ve never been an Interstate fan but the X2 is supposed to be a good battery. Has anyone had similar experience? How about those of you using the new Miin Kota chargers?

My back can't handle hauling these 80 pound batteries out of the boat every year...

[catdude28]

Your DP Pro Series charger is more than suitable for your specific AGM's, and in fact, more compatible than many others. This doesn't mean that yours is actually working properly though.

The Interstage 31 AGM's are not very popular here, and do not have a really good reputation. On the other hand, as you know, the X2/Northstar is very popular, and is considered a beast. It should not be running down after only 16 months.

Voltage measurements for the charger output during various stages, and batteries, done with a good voltmeter, are likely in order. Somebody with more knowledge than me should be along shortly to give you specific instructions. The assumption also is that there is no parasitic drain.

[hekistner]

I have a 2016 Ranger Z520C with the original Dual Pro 4 bank charger. I am getting very poor life out of my AGM batteries and wondering if it could be related to my charger. I don’t think it should be the charger and I have always had good results with Dual Pro in the past.

My trolling batteries are Interstate group 31 AGMs. The first set lasted one year and were replaced under warranty. Exactly one year later the new ones are going bad. Interstate is replacing them again. I give them credit for honoring the warranty but they shouldn’t go bad so quickly and it is a PIA pulling them out and exchanging them.

My cranking battery is the group 31 X2 from Batteries Plus. It is 16 months old. It charges fine but now runs down very quickly during the day. It is down below12 volts in less than an hour with 2 graphs on. Yesterday I had to jump it by 11 am and we weren’t even running the livewells.

I use the boat year round. I plug the charger in immediately after each trip and leave it plugged in until the next trip. All banks show green by morning the day after using it.

So the question is whether the charger is poorly suited for these batteries or are the batteries just junk? I’ve never been an Interstate fan but the X2 is supposed to be a good battery. Has anyone had similar experience? How about those of you using the new Miin Kota chargers?

My back can't handle hauling these 80 pound batteries out of the boat every year...

I have had the same problem with ProGuide group 31 AGM batteries. They replaced them once but when the same problem came around again they said that the 2nd time was not a warranty because the warranty started with the purchase of the 1st set and a year later the 2nd set was out of warranty which sucked. Their 2 year warranty of free replacement batteries was only good for the 1st set. High dollar AGM battery warranty not worth the paper it is printed on. The charger was a 3 bank ProMariner which was suppose to be a good charger for AGM batteries. Other people have used the ProGuide batteries with no problems with them lasting 5 or more years but I did not the same luck..

[billnorman1]

Unless you are using the trolling batteries to the point that they are reversing cells due to being too low, it doesn't sound very good for the batteries. As a general rule I don't bash brands, but an AGM 31 should be as tough as nails. Many of us are using the Sam's club Duracell AGM size 31. Inexpensive. Make sure you are using a dual purpose battery for the outboard battery.
Personally I use a Duracell dual purpose AGM 31 for my main, and Walmart Neverstarts 29's wet cell for my trolling batteries, I fish a LOT and they work very well for me.
Is your motor capable of charging an AGM? I've heard some Merc's cannot and that the Sam's Duracell barely meets that motor's minimum CCA requirements, but I've also heard some Merc owners use the Duracell with absolutely no issues.

[bandit53]

I think a call to Dual Pro would be a good start. I have been running Northstar AGMs (Northstar manufactures X2) on my last 2 boats and never had an issue, but that doesn't mean 1 can't or won't go bad. I assume the X2 has the same 4 year warranty as Northstar.

[bayoufellow]

Check with Dual Pro first. Also check your wiring 6 gauge from battery to battery and to trolling motor. (I use 4 gauge for this). If new batteries are needed, give Odyssey a look (31M-PC2150ST). Mine are 8 years old and still going strong with the Dual Pro charger for AMG batteries. They are not cheap up front, but pay back over time.

[rangerranger]

Thanks to all who replied.
Dual Pro conformed the charger should work well with these batteries. Ranger wiring is also appropriate.
2 out of three of the Interstates tested bad and were replaced under warranty. They lasted 1 year, same as the originals that came from Ranger.
The X2 cranking battery also tested bad and was replaced under warranty.
All 3 of these batteries looked fine when connected to a voltmeter. However the stores put them under load and they crapped out pretty quickly.
Its disappointing to have to deal with this but I at least give Interstate kudos for restarting the 3 year warranty. The X2 warranty does not restart, it dates back to original purchase date.
As long as Interstate keeps replacing them I'll stick with them but if it becomes time to put out cash I'll go back to Dekas which have served me well in the past.
Hopefully battery technology will catch up to our boating needs sometime in my lifetime.

someone asked if my motor can charge the cranking battery. I have a G2 250 which recharges it very quickly. The issue is the cranking battery runs down very quickly while I’m fishing with graphs or any other accessories running.