I need to get a new pair of batteries for my boat. Currently I have 2 deep cycle, CCA 460. Mechanic recommended I get 800CCA. Should I get one starter battery and one deep cycle? I do have a large stereo system in the boat. What is the best way to go? Thanks in advance!

Just bought 4 750s for my boat. 1 for each engine, 1 for the house (radio) and 1 for the gen. Replaced them like for like. Id have at least a pair of 650s if I was you

460 CCA sounds low. My Merc manual recommends 750 CCA for my motor.

What type did you buy? There are so many out there.
I was thinking of getting a Super Start batteries from Oreilly auto parts. 1 marine starting battery 800 CCA and 135 minutes of reserve, and 1 deep cycle 675CCA and 210 minutes of reserve.

del

I agree I bought the boat with the 460 CCA in it, never thought to look to see if they met recommended specs. I wonder if it made a difference on performance etc?

4 super starts here the ones I pulled were 5 years old

Yes, one starter battery and one deep cycle. Isolate (ie: use an isolator) the two so they can charge,,,assuming one motor and alternator. Hook stereo to deep cycle.

Deep cycle's aren't built for sudden rushes of large current a starter uses/creates.

Normal starting batteries aren't built to run much lower than 75%.

Google the info and it will all become clear. IE: info from the manufacturers, not just an internet azzhole like me with an opinion. LOL.

I prefer AGM's to wet lead acids in my boats.

Boat 1
Has been running odyssey pc2150's which are 100AH each.
They function as both high amp and deep cycle.
I use a simple perko 2 battery switch as an isolator.

Boat 2 has Optimas in it,
These are nowhere near as good as the odysseys in my experience.

UD

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