Having to replace 2 of my batteries. I was curious what batteries yall use and which ones give the biggest bang for the buck. Thanks for your input.
When you say "replacing two" is that two for a 24V TM, or 2 of the 3 for a 36V TM? I ask because it is best to replace all in a series connection at the same time. This is because any remaining battery (batteries) will eventually begin to fail, dishing out more abuse of the newer battery(or batteries). Overall, you'll be happier with a set at the same age, whether it's a set of 2 or 3. Just to be clear, a standalone starting battery isn't part of a "set" as it isn't connected to the TM batteries.
I had 2 batteries go bad...one was on the trolling motor side and the other was my cranking battery. I have already decided to go ahead and replace all 3 for the reasons you have stated. Great input..thanks.
Your boat size, outboard size, and amount of boat accessories (such as how much electronics) play into what battery is "enough". For a big boat that can take the weight, it is hard to beat a Group 31 AGM battery. It has the MCAs that meet spec for the big Mercs, and a nice deep cycle reserve to boot. I agree with many here that the Sam's Club AGM Marine battery is hard to beat for the price. You may not need a Group 31 in your application. For TM use, I don't feel there's as much of an advantage for AGM, but some are willing to pay the extra to never have to check the electrolyte level in batteries. Stored energy-wise, the Sam's AGM is no better for TM use than their traditional "low maintenance" marine battery also available at a very good price.
I just put two of the Sam's Club AGM's on my boat for my trolling motor. Only down side is 70 lbs each. I thought I was going to have to have help lifting them in there. 140 lbs right on the back of my boat just in front of the 600 lb motor.
Wayne
Luck will beat skill any time you have enough of it!
If weight was your concern (69#, not 70#), you could have gotten the same energy (for deep cycle, 105 AH) from the lighter weight wet-cell batteries Sam's sells. Those are 60#. The AGM doesn't give any advantage to TM use other than no electrolyte check needed; that AGM has the same deep cycle profile as the wet-cell.
Super Start brand from O'Reilly Auto are East Penn batteries which is who makes Deka and Duracell. Same exact batteries with same specs. Check out 34MAGM, 27MAGM, and AGM31DT. Or for starting 24MS or 27MS. Been using for years with great success.
Reason I went with AGM was that I ruined the flooded batteries by letting them go dry. I know, MY BAD, but, I topped all three batteries (cranker and two trolling batteries) on the same day. When the trolling batteries went dry and were ruined, I checked the cranking battery and it needed no water at all. It had only been about 2 or 3 months since I had filled them. I have no idea why the trolling batteries went dry so quickly. They were a PITA to fill because of their location, so now I have AGM's. One less thing that I have to do and at the burden of extra weight, I went from 27's to 31's.
Wayne
Luck will beat skill any time you have enough of it!
Ok...So I bought the Duracell batteries. On the front it states “starting and cycling”. Is this a dual purpose battery used for starting the engine and also a deep cycle battery for the trolling motor side? Also...when I install them should I go ahead and hook them up to the charger for maintenance reasons or wait until I use them for the first time?
No, that battery won't do squat as a trolling motor battery. It's AGM, and that's about it as it's the smallest weakest AGM offered at Sam's Club. When you see a lot of guys here speak about "get the AGM at Sam's" they are implying the BIG battery - Group 31, a real beast compared to the Group 34 you bought.
Labels aren't where you find the real application match - you have to look at the specs. You haven't said what motor you're cranking with the battery, and that matters a lot. The specs of that battery are under what Mercury specifies for a number of their outboards. You need to look at the manual for your outboard to see what the minimum cranking amps is, usually expressed as "MCA" (Marine Cranking Amps). That battery has 890.
You never said (though I keep asking) about how much electronics you have. A Group 34 may meet your starting spec, but there's a reason a lot of us run a Group 31 AGM, and the difference is HUGE (not just "3").
For Trolling motor: What motor do you have? volts and pounds thrust? This matters. Unless you're in a jon boat, I wouldn't even try a Group 34 battery. That one is only rated at 55 AH (amp hours) at the traditional 20 amp rate category. A group 27 deep cycle battery on the other hand has from 80-95 AH. Reserve minutes is another good way to compare for deep cycle use. The group 34 has a puny 120 reserve minutes compared to 175 for the Group 27 battery in the same family. The wet cell Duracell Group 27 Deep Cycle battery is only $82, and has a Reserve Capacity of 175 minutes. 175 for $82 or 120 for $120 where more minutes is better. Group 34 AGM is not where it's at for your TM.
Batteries should always be charged before use. They are never shipped with a full charge, and they lose some of what they do have while sitting on the shelf. Unless you have a small boat, at least two of those 34s really should go back. Get a Group 27, AGM or not. My opinion is that for TM use, the extra $ for AGM is no bonus other than no need to check electrolyte every 2-3 months.
Whatever battery you get make sure you charge them back up as soon as you get back from fishing....I have the on board charger plugged in almost all the time at home to keep them topped up.. and have 2- 2014 and 2 2015 walmart batteries with about 175 trips with an average of 5-6 miles trolling....that's how you get the most out of a battery...technically you should not go below 50% charge on each battery before charging up full again...one of them doesn't hold a charge as good anymore and use it just for accessories now...you really need to get a starter battery for cranking the engine and deep cycles for the trolling for a bass boat with multiple batteries..dual purpose batteries do half a good of job for cranking life and half a good of job for constant amp pull of trolling...
