Well there are several folks on here that swear by the blue tops. There are some that have not had such a great experience with them. Some have had no issues at all...

Another consideration is the Diehard Platinum marine AGM's from Sears. Some folks on here have had great experience with them too and they are a bit less. But once you get in the $200++ range for a battery well its a lot of money all around.

I'll be looking to replace my 'wet' batteries next year... So best of luck!

One thing to do is measure your existing battery trays to make sure they will fit. Make sure of the height clearance too. The blue tops seem to be a bit smaller then the normal Group 31 batteries... There is no wrong one. It either a yellow top (group 27?) or a blue top (group 31). Its all about capacity and cold cranking amps (CCA) to turn over the engines..

Someone posted about these needing a special charger but your boat most likely being so new has the pro-mariner charger on it, there is a setting for AGM batteries MAKE SURE you set it to that if you are going from WET to AGM style batteries... You really don't want to hurt the new AGM batteries by not doing that!!!

 

a special charger but your boat most likely being so new has the pro-mariner charger on it, there is a setting for AGM batteries MAKE SURE you set it to that if you are going from WET to AGM style batteries... You really don't want to hurt the new AGM batteries by not doing that!!!

Not necessarily true. Some chargers' settings at wet cell are more closely aligned with the needs of the Optima AGMs. I made the same switch 2 years ago. No regrets. I did not change any settings on my charger. AGMs are lead acid batteries - just a different configuration. If for some odd reason you choose to go with gel batteries, they required a much lower charge and trickle rate.

Bottom line - compare your charger's output in the various settings with the requirements of the batteries you choose. AGM's are not too different from classic wet cells when it comes to charging needs.

 

I have a few gremlins running around my boat and I suspect that I have at least one bad battery that may be causing the issues.

· Outside stereo speakers shut off when boat is unplugged and engines not running
· Generator shuts down and I get an EC72 code
· 4 light bulbs burned out in a 1 week period. (1 arch light, 2 walkway lights and 1 navigation light)
· Radar stopped working.

I am considering trading in my boat for something a little bigger over the winter, so I don’t want to replace all of the batteries. I would like to just replace the one battery that is bad, but I’m not sure how to isolate it. I don't own a load tester and not sure if taking voltage readings will tell me anything. I have 4 batteries, so I may just disconnect all of them then use jumper cables and my bow thruster to do a load test :grin:

I did some research on this site discussing the AGM batteries and liked what I read. The existing charger should work fine, you might get away with leaving them in the boat over the winter, no fumes or acid to spill on your clothes, no water to check and they should last 2x as long as wet cells. Down side is they are expensive and are much heavier then regular batteries. If I knew for certain that I was keeping my current boat, I would buy 4 of them at the beginning of next season.

 

After doing the research I replaced my house/port side batteries with the Sears Diehard 31M Platinums. They were even more "spendy" than the Optimas, but they fit the boxes and I liked the idea of dealing with Sears if it is necessary to invoke the warranty. Love the extra power of the Diehards.
Good Luck...Dan

 

Thanks for the feedback. I might try to keep my current set running until the season is over and then get the new Optimas in the Spring. The current set seems just so impractical. I think just to check the water level I have to spend an hour in the engin compartment. :smt009

 

I replaced mine with AGMs this spring. The only thing I had to do was re program the sub woofer on the stereo. Of course what with having both hips replaced in 6 months this year my boating has been limited to the early spring between operations.
I will definitely make up for that next year.
Take care,
George

 

I changed the 2 group 27 house batteries for 2 6 volt golf cart batteries in series.I'm very pleased with the results.Done for less than $200.

 

I changed the 2 group 27 house batteries for 2 6 volt golf cart batteries in series.I'm very pleased with the results.Done for less than $200.

This is what my marine mechanic told me to do. He is very good and very experienced so I trust his judgement. He metioned that if I go this route I should be set for 10 years. I will be looking into these batteries. :smt038

 

I replaced my batteries this spring with West Marine Group 31 AGM's as I was able to cut a deal with our local West Marine store manager and got them for right at $200 each which was much less than Optima or Odyssey batteries that I was also comparing against. So far the results are very good. When we are out running both refrigerators I can go 24 hours with approximately 1 volt drop. Running my generator for about two hours a day keeps the voltage maintained. Just got back from six nights out and that worked well. Also, I did not adjust the settings on my battery charger and the Group 31 batteries fit perfectly in the trays in my '05 320 so would expect the same in your '06.

 

I am having problems with my 2.5yr old batteries on my 320 SeaRay. On the hook I can not run my fridges for more than 2 hrs before the voltage drops to the point where I have to use the emergency starter button.

I understand that investing in top nuch batteries will help you, but my first thoughts after reading this were that there's something not right and you have some component(s) that drian the juice. If I'm correct, then new and powerfull batteries are no more than a "bandaid" and only a short term solution. I suggest you take the time and find the source of the juice leak. There's always a possibility that somehow you failed to maintain your batteries and they simply lost their performance, but I assume this is not the case.

Just my .02c.

 

It could be, but 2 1/2 years on an '06 could really be up to 4 years on those batteries. Plus, these boats don't do well on High CCA batteries. They need deep discharge the way that most of us use them (up for debate). Since most people talk about how many hours they are on the hook without the genny...., we are deep discharging them. Deep discharge batteries are the way to go. Also, 4 years on a factory wet cell, or even 2 1/2 years, is pretty good.

 

John, I don't disagree with you. As with anything, the key is how it's used and maintained. I've seen these batteries go for 4-5+ years. So, when I see 2 1/2yrs batteries (all 4 of them) holding up only for 2 hours they either been improperly used and shut or there's a big time juice leak. I also heard that many 320s are equiped with group 27 batteries and they hold fine for a years. I think that OP has to look back and recall whether there was an error on maintaining the batteries or there's another contributor to the issue. Regardless, owning number of used boats and cars, getting only 2.5yrs out of 4 batteries is not normal to me and would be unaccessptable.

 

I just got the boat this spring (used) so I don't know what they did to the batteries.

I will check my charger manual and see what is installed right now. But I am leaning towards the Deep Cycle batteries just so I don't have to worry about running empty over night.


What is the difference between a Group 27 battery and a Group 31?

 

Just purchased my 2005 320 DA and I negotiated new batteries as part of the deal. The Searay manual indicated grp31's but I found grp27's from the factory! I purchased grp 31's Power Batteries wet cells and the broker and I installed. Those grp31's are 65 lbs and are heavy! Definitely a 2 man job so you don't have to get down and up from engine compartment. Hope that helps!

George

 

My 06 320 has 4 Interstate Group 27 "Cranking" batteries. I was surprised not to find group 31 deep cycle. I bought my boat used, so I can't say that they were from the factory, but I doubt that the former owner replaced all 4 batteries within 1 year of service.

 

I put a blue optima battery in my small sea ray, and it only lasted one year... I traded it for a lead acid battery that works fine... I think it was not compatible with my charger... I plan on replacing my house batteries on my 340 in the spring... I think they are 8 years old. They were well maintained and 8 years is pushing their life.

 

Merc lists a min of 1000 CCA for my 08 350s, unable to locate deep cells with that rating yet.

 

You can look at Inerstates' website to see the charts. Group 31 are slighty bigger in size and capacity.

http://www.interstatebatteries.com/cs_estore/content/product_info/marine_f.asp

 

My 340 also came with 27s.. Replaced them with wet cell 31's a year ago. They work fine, but what a PITA to keep filled with water. My bill for the Pain Management Clinic has far exceeded the extra cost of Optimas.

 

Well, after some further research and opinions from more people I am also looking at a chaeaper alternative. The 27 Deep Cycle Walmark EverStart batteries for $70 each seem to work for some and for that price, I can keep replacing them for a few years before I get to the price of the Optimas.

$$$ & Low Maintenace vs. $ & some extra work :huh:

But then again, I am not the maintenance kind of guy.

Thanks for all the advice!!

 

Before you start spending money I would contact SR and see what type of batteries they recommend. I was told that it's not a good idea to put just deep cycle batteries, b/c you need extra cranking amps to get those egines started. My boat was equiped with 27s and I lost only one before this season. I replaced it with group 31 ($120 from MM), which has more cranking amps. I don't remember all the specs, but it's not deep cycle.

 

So I ended up getting the Optima Group27 blue top for my boat.

Do you need to trickle charge the AGM batteries in the winter when the boat is on land storage?

 

I initially clicked on this post with hopes of helping me decide what to do- I think now, I'm even more confused

We were on the hook all weekend in one of the state parks in South Puget Sound (saw a Killer Whale pod about 200 yards off on Saturday). We've not been "disconnected" for agreat length of time all summer. This weekend I was dealing with a similar issue as the OP had. About every 2-3 hours and I'm running the gen set just to get some more juice going. And by then the house batteries are so dead I've got to start the main engines to get the genny even started.

I'll confess about a year ago I had a dead battery late one afternoon and checked it the next day to find two cells way low on water. So, I may have helped speed up the battery aging process back then.

Regardless, like some of the other posters say, checking the water is a PITA since these things are not fun to get to.

I may wait it out until mid-winter when all marine products go on sale.....

 

Regardless, like some of the other posters say, checking the water is a PITA since these things are not fun to get to.

..

That is exactly the reason I got the no maintenance Optimas. I don't want to spend an hour just to check the water in the summer. :thumbsup:

 

Switched out all 4 of my originals with Optima Blue Top love em so far but only one season on them. After years of replacing standard flooded acid every 3 years looking forward to many years on the Optima's. Got my group 31 local with an online coupon for $175 a piece, not worth even considering standard flooded for that price difference. Plus never have to add water to them, that by itself is worth the extra price.

 

I have the option of getting grp 34 cracking optimas for $161.00 each. I rarely am on the hook without the gen running and my current batteries are grp 27 cracking Interstates. What does everyone think of the grp 34 optma cracking batteries. CCA and MCA are rated the same as what I currently have. All I have to do is make sure they fit.

 

isolate the batts. charge both over night. let stand for a day.(no load on either) use a cheap volt meeter and read voltage. if one is drasticly diff. ( lower ) thats the bad one

 

I have 4 group 31 Blue Tops in my 340 Dancer, they have been great so far. The stock Interstate group 27s that Sea Ray put in new were fading fast on year four when I switched, BTW Sea Ray calls for group 31 but then put group 27 in them new, not sure what's up with that.

As stated in previous post adding water once a month is a PITA especially on the port side as they are awkward to get to on a 340, so worth the extra price on that point alone. Over the winter when they are not in use they don't lose any charge, another stated advantage that holds true, plus sealed so no fumes or corrosion.
Before I bought mine I read on another thread a guy had them in a larger Sundancer with diesels and they were 9 years old, that pushed me over the edge to move up to them. $161 sounds like a great price, good luck.

 

You might want to check out this link from a previous post, the Optima group 34 have less CCA and reserve than the group 31.

http://www.interstatebatteries.com/cs_estore/content/product_info/marine_f.asp
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Interesting information...

http://www.windsun.com/Batteries/Battery_FAQ.htm

http://www.batterystuff.com/tutorial_battery.html