Need a cranking battery

[nitro61]

Fixing to replace the starting battery(2002 Merc. 115 hp serial # OT538976) wondering if this engine can run and charge the lithium battery? Thanks Bob

[06 SB]

I am pretty sure that is a carb’d inline 4 cyl ELPTO. Lithium in not recommended for any carb motor. You should look at the NAPA PN 7234 or 7235. It is a good battery with plenty of juice.

[nitro61]

Thanks, and it is a carb. 4 cyl. Will check out the NAPA that you suggest.

[fly by night]

Another vote for the NAPA battery, a beast for sure and leaves you heavier than some in the wallet area! LOL

[EuropeanAM]

Need a lead-acid CRANKING battery (traditional wet-cell, meaning you can remove caps and check/correct fluid level if needed).

Do not use AGM, Maintenance Free, Deep Cycle, etc.

[nitro61]

Thanks, was just looking for a way to reduce some weight in the back. Don could this be relocated to middle of the boat in the center? Whent with the NAPA and relocating would make maintenance on the battery a lot easier there is very little room in the back. All that is on this battery is live well pump, bilge pump and a Lowarnce HDS 9 and of course the running lights.

[EuropeanAM]

Shouldn't be a big problem if you have the room, and adequate cable length (factory cables were 12').

[nitro61]

Thanks Don. Will look into moving it to the middle (center)

[06 SB]

I have moved batteries around a whole lot. Make sure you seal any open holes.

[Whitaker201]

I am replacing a battery for the same motor. How many CCA should I be looking for?

[EuropeanAM]

I am replacing a battery for the same motor. How many CCA should I be looking for?

Need to keep separate engines in separate threads to avoid confusion. In a fishing application- I'd recommend 800CCA (no less than 650).

[fishnkamp]

Hey Don I am just curious why you dislike using a high capacity dual purpose AGM. I have been running 3 of the old style Cabelas dual purpose group 31 AGM batteries on my 2010 17 foot Lowe bass boat for almost 10 years now. The boat has an 2002 3cyl Merc 75 on it. Of course I am about to replace them. I sam I missing something? To get that long of life out of them I obviously recharge them immediately after each time on the water.

[SilverFox579]

Hey Don I am just curious why you dislike using a high capacity dual purpose AGM. I have been running 3 of the old style Cabelas dual purpose group 31 AGM batteries on my 2010 17 foot Lowe bass boat for almost 10 years now. The boat has an 2002 3cyl Merc 75 on it. Of course I am about to replace them. I sam I missing something? To get that long of life out of them I obviously recharge them immediately after each time on the water.

Because Mercury does not recommend them for engines with stator style charging systems. Belt driven alternators, yes, stators, no.

[EuropeanAM]

+1

That is a Manufacturer Recommendation, as there is a higher likelihood of over-taxing the charging system (stator and voltage regulator) with batteries that are not simple WET cell Cranking Batteries.

[Rodbolt]

Deka battery chart for older outboard cranking batteries, Mercury on pages 2 and 3:

http://www.dekabatteries.com/assets/...ionslayout.pdf