What batteries?

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I have a 1994 232 GS with twin 1997 Yamaha 2 stroke salt water series outboards. What batteries would you recommend? Deka 27m6?

Thank you!
 
How will you be using the batteries?

You didn't mention what engines you have?

Regardless, you certainly don't need a big battery to start (I'll assume something like a 150HP) smaller engines. Group 24 is MORE than enough.

But.. the first two questions need answers to start with.
 
Says in the post which engines the OP has... To the OP, I replaced my batteries back in the late fall/early winter of 2023, of which I called up my local Grady White dealership asking them what they recommend doing, and they said to just replace what I currently have with the same brand new batteries. The old ones in my boat were Interstate brand 24M-XHD cranking batteries, so I just bought the exact same ones as replacements and haven't had any issues since doing so. There are a ton of different battery sizes, types and brands out there... and as such I imagine you're going to get a bunch of different opinions on the matter. Costco also sells Interstate brand group 24 as well as 27 batteries, but they only offer the deep cycle versions. Good luck.
 
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You are right! Sorry. They are twin 150 HP Yamaha two stroke engines. I will be running all the usual systems plus a sound system.
No worries, my friend!

To be more specific, how much use of various items will you have with the engines turned off?

Also... "usual systesms" can vary quite a lot from one person's opinion to another :)
 
With engines off we are really just talking about the sound system….sand bars etc. I would rather have access power and spend more on the batteries up front. Is the deka 27m6 overkill?
 
Oh... do you have 2 batteries? Or do you have an extra one or two batteries for the house load? Sorry - should have asked that ahead of time.

All of these things get factored in to the equation!
 
Nope, it absolutely does not. Where do you see the size/HP listed?
The boat is a 1994 GW 232 Gulfstream, of which it has a maximum horsepower on the hull of 350 hp. The OP stated the boat has twins on it, of which one could deduce that they're likely going to be twin 200's or less.

To Germanmattlanta... does the boat currently have batteries in it? If so, what are they? I'd just replace what you have with new versions of the same batteries.
 
OK, so it really comes down to how long you're going to be using battery power without the engines running. Without a dedicated house battery to use for this purpose, you're kind of in the middle of "recommendations". Which also means there's leaway with recommendations. Best practice is a starting battery for an engine and a deep cycle for "engine off" power. Using the batteries for the wrong purpose can shorten their life.

I like that you're asking about Deka - they're pretty much the best ones out there. Interestate would be my next go to.

You don't need heavy cranking power for those engines, so that "variable" is out.

But, you do need the benefits of a deep cycle (power use when engines are off).

But because you only have two batteries, we're back to a bit of a compromise. The best way to solve this is to use a dual purpose battery. It's not "as good" as the "best practice" I mentioned above, but Deka makes a very good DP battery that is basically as close enough as makes no difference.

I would go with either their Group 24 or Group 27 DP... DP24 or DP27.
 
The boat is a 1994 GW 232 Gulfstream, of which it has a maximum horsepower on the hull of 350 hp. The OP stated the boat has twins on it, of which one could deduce that they're likely going to be twin 200's or less.

To Germanmattlanta... does the boat currently have batteries in it? If so, what are they? I'd just replace what you have with new versions of the same batteries.
You're welcome to assume....... but leave "me" out of the equation.
 
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