Marinette Boat Forum

I am buying a 1978 28 express hardtop, single 318. I am wondering if anyone knows what battery group/ size this boat would normally take. I am buying this out of town and want to get a battery or two for it before I head out to pick it up and give final payment. Thanks in advance for the help.

I have a 28' Express/single engine and use 2 batteries. Both are the "Everstart" (Walmart) brand and have worked well so far.

One is a "Marine Cranking" battery and the label says it has 625 marine cranking amps. The other battery is a marine deep-cycle type with 690 marine cranking amps. My boat has a battery selector switch and I normally set it to use both batteries when I am starting/running, but I would think that just the standard cranking battery would have enough juice to start the engine on its own.

Hope this helps...

I recall vaguely that the group size was either 24 or 27. From BatteryStuff.com, I clipped the following:
Are you looking for a marine, RV, automotive, or solar PV battery? You may have heard common terms like a "group 24 battery" or "type 27 marine battery". These numbers are referring to the BCI Group Number of the battery. These numbers define the physical dimensions of the battery case. This is important as some applications call for specific case sizes. The BCI does not determine the Amp Hours (AH) rating for the batteries, however, but there is a correlation between case size and AH rating. For deep cycle batteries, the larger the case size the more capacity the battery will usually have. .

Therefore, the battery size you choose will depend among other things on the space you have for the battery. Industry lore is that "marine" rated batteries can better withstand the rough treatment they get in a boat. I have no idea whether that is actually true. But I did find the following on the eHow web site:

Marine Batteries
A marine battery usually will have thicker plates that an auto battery and therefore less cranking power, but longer reserve capacity. A higher power marine battery has larger, but not thicker plates, and will have a longer reserve capacity. A typical marine battery can be discharged to 20 percent. Batteries with even thicker plates may be labeled "hybrid" or "deep-cycle" marine batteries and can be discharged to 50 percent before needing a charge. These may be constructed exactly the same as some batteries designated "RV."

The Marine Problem
To quote David Pasco in "Boat Battery Basics," an Internet information site, "The usual reason why boat batteries are dead is due to having the wrong type, size or quality to meet the vessel's demands. Truly good batteries are expensive and there are few boat builders that provide good batteries with new vessels; usually the quality is minimal, the amount of power inadequate, and the type ill-suited." So even in a new boat with a new battery, upgrading to a higher-quality battery may be the best option.

Battery Specifications
Ampere hour rating is the most common specification and is calculated by multiplying the current in amperes by the time in hours that the current will flow. Cold cranking amperage (CCA) indicates the maximum starting current the battery will provide for 30 seconds at 0 degrees F. Reserve capacity tells how long the battery will put out 25 amps before needing a charge. These specifications apply to all batteries designated either automotive or marine and should be used to determine how a battery best serves its intended purpose.

Conclusions
For a speedboat with a 400-cubic-inch engine in Minnesota, the best choice could be an auto battery with a high CCA. For an RV going on a camping trip, using lights and music all night, or for a pleasure boat with the same plans, either a marine or an RV battery with a higher AH rating and longer reserve capacity would be the best bet. Or, for those who can afford it, a much heavier deep cycle industrial battery can discharge right down to 80 percent before the lights start to dim.

Read more : http://www.ehow.com/about_5584809_auto- ... eries.html
-------------------------------------------------------------------
Meanwhile, good luck with your new toy

For some reason group 27 sticks in my mind.
I guess the size will might on what the previous owner has for battery boxes unless that is not an issue.

Been running group 29s on the 32'. The extra juice is always welcome.

-GB

Joel...

Your info - Outstanding!
You rock!

Bill

27 is what I have. I can tell you; you get what you pay for in a marine battery. I have used the Auto Zone junk,. I have used advanced auto junk. They both burn off water too quick on my dock charger. I know, I know my charger is not the most advanced up to date charger All I use now is Interstate marine batteries.. No burn off problem and lots more lead in them. I think they are an economical option for non commercial boaters.
Group 27. Find a local dealer for interstate batteries and call them [url] https://interstatebatteries.com//[url]

Thanks for the input guys. I am leaning towards the interstates as I can get them from the local northern tool store and they have coupons out right now. My other thought is Wal-Mart, I've heard they have decent batteries there, but I have had good luck with the interstates in the past.

Menard's has a $69 spring sale of Exide 27's. I got a pair for $110 with $10 rebate and two $9 trades. Walmart also has a sales. Seems like once a couple of palettes are gone that's it.

I like the Interstate batteries as well. I have also had good luck with Napa high end batteries. But I am thinking I want AGM or Gel for my boat.

http://www.westmarine.com/WestAdvisor/S ... ge-Battery - Good read.

http://www.westmarine.com/marine-batteries

I wish I still had my walk in West Marine here in B'ham !!!

http://www.boatersplus.com/?subcats=Y&s ... cts.search

http://www.amazon.com/Shoreline-Marine- ... 353&sr=1-2

Here is a link to Interstate's Marine selection.

http://www.interstatebatteries.com/m/category/marine


I'm going to order a set of the Pro-SRM29 ECL batteries from my local dealer. Interstate claims the ECL line approaches AGM performance at a fraction of the price.

http://www.interstatebatteries.com/m/pr ... ofessional


Don't forget a set of terminal protectors. Much better then the spray or goop all over the place.