Battery problems...

[Steve Johansen]

Hi guys,



First, a brief history...



I had a 2 bank charger in my boat that I used each time I returned from a day's fishing to bring my two trolling motors back up to a full charge. Sometimes I left the charger going for a long time, and sometimes I didn't. I just assumed that it was OK to leave this thing plugged in.



Last year I started to notice that I wasn't getting the same amount of run time out of my batteries but since I had added some extra electronics and a stereo I assumed that the extra load I was putting on the batteries was causing the shorter run time.



With the recommendations of people on this site I agreed that maybe I should add another battery for my accessories and leave the two trolling motor batteries strictly for the trolling motor. I added another battery for my accessories and I was now faced with not being able to charge the new battery that I had just added.



I went to a local supplier and purchased a 3 bank charger (Pro Marine, I think) and wired it up to maintain the two trolling motor batteries as well as my newly added accessory battery. Problem solved? Not really.



I am now finding that I am only getting about 1/2 of a day in and noticing that the trolling motor is slowing down.



I thought that maybe the 2 batteries have crapped out. They were bought new from Costco 2 years ago. They are the Blue Top Optimas. I really don't want to think that they are junk already but what else could it be?



Is the charger not doing it's thing? The third accessory battery lasts all day without a problem, so I think that the charger is working.



The only thing that I can come up with is that the original 2 bank charge that I removed maybe had cooked the Optimas last year and over the winter (while being plugged in to the new 3 bank charger) have finally packed it in. The new charger is supposed to be 'smart' and will not over-charge but I am not so sure about the old 2 bank one that I removed.



Being a sealed battery I cannot check the state of the acid inside the Optimas so I don't really know where to turn. I can return the Optimas (Thank you, Costco!) and replace them with something else but is that really where I should start? How can I tell what has let me down? The old charger? The new charger? The Optimas?



I want to go fishing this weekend and the way it is now I will only last a few hours before I get mad again!



I have a little hand-held load tester that says the Optimas are good when charged and are next thing to dead when I return but a guy at a battery store told me over the phone not to trust my load tester. He is leaning towards a charging issue.



Am I correct in thinking that the new charger is OK to leave plugged in for extended periods? I am not at all sure about the old one.



Any help will be greatly appreciated!



Thank you in advance and sorry about the long rant but I wanted to explain my situation fully so there was nothing else that you would need to know. I hope I have done that!



Steve

 

[Scott Hammer TOXIC]

From Optima's web site:

BlueTop Type: 34M

These batteries are designed for engine starting applications. They are NOT recommended or warranted for use in deep cycle applications.

I think you have the wrong batteries in your boat and are not using them for their designed purpose.



TOXIC

 

[Jim in VA]

Steve - not sure if you can do this with sealed batteries, but try taking them to an auto parts store that sells batteries and have the Optimas load tested on a heavy duty load tester. They should be fully charged when you take them in. That will give you a better idea of the batteries are toast or not. If they are toast, take them back to Costco.



I know that doesn't solve the source of your problem, but if you replace the batteries and have a new ProMariner charger, you've hit the two possible sources. Not sure what you had for the original charger, but its very possible it did cook your batteries. I had a "smart" charger on my first bass boat do that to me and had to replace the charger. The ProMariners have a pretty solid rep so hopefully you have the same problem.



Good luck and keep us posted!



Jim

 

[Scott Hammer TOXIC]

Batteries not made to function as deep cycle will discharge very quickly regardless if they are good or not. Blue tops are starting batteries not deep cycle. They may work ok for a while but they will crap out very quickly.



TOXIC

 

[Herndonpro]

The Optima blue tops are their marine battery, but there are different models. There are deep cycle models. The link has specs for each of the blue tops. I've been using the same set for my trolling motor for three years with no issues.



Steve
http://www.optimabatteries.com/optima_products/bluetop/specs.php

 

[Scott Hammer TOXIC]

I forgot about that....Then he better make sure he has the right ones!!:lol:



TOXIC

 

[davetnitro]

from optima's website



Battery Model: D34M

Part Number: 8016-103

Nominal Voltage: 12 volts

NSN: 6140 01 475 9355

Description: High power, dual purpose engine start and deep

cycle, sealed lead acid battery





i use this battery for cranking,





and 3 of these for trolling motor, i keep the charger plugged in 24/7



Battery Model: D31M

Part Number: 8052-161

Nominal Voltage: 12 volts

NSN: 6140 01 502 4405

Description: High power, dual purpose engine start and

deep cycle, sealed lead acid battery

 

[Steve Johansen]

 

[Rob Brumfield]

Steve - I believe that you may have encountered the same issue that I did with my previous boat batteries and charger. When you switched to the Optima AGM batteries the first charger you had most likely wasn't for AGM type batteries. AGMs are gel cell batteries and can not receive any more than a 14v input charge. Any higher will fry the battery. The ProMarnier can be used with AGMs and it will only put out 13.8v.



I wasn't aware that a special charger was needed and I ruined 2 Optima D34M batteries before I figured it out. My Z9 came with a 2 bank Guest charger and it wasn't AGM compatible. The first thing I did was to swap it for a new ProMariner Tournament 150 3 bank charger and then swap the Interstate acid batteries for the Optima batteries. I kept them from my old boat. I get about 3x the run time on the Optima batteries.



The ProMarnier can be left on and it will keep a maintenance charge on all the batteries. I have run the D27M for the cranking battery and the D34M for the trolling motor batteries for years now without any issues. The first Optima I had to replace, not counting the ones I ruined by over charging but from old age (lost a cell) was 6 years old when it failed. I never had that kind of luck with regular acid batteries. Two or three years tops, before having to replace them.



I hope this information helps.



Rob