How Many Cranking Amps for a 115 Merc 2 stoke?

[TrepMan]

Gang - Cranking battery is on its last leg, plan to get a new one tomorrow evening. Reading on a few sites, different motors need different cranking amps. Any clue on what I need for a '99 115 Merc? I'll check the current battery tonite to see what it has, but any suggestions?



Trep



OK Found this on the Merc site:

2 stroke Motor = 75 - 125

525 Marine Cranking Amps MCA) or 450 Cold Cranking Amps (CCA)



I've also read on a few sites that if you have lots of electronics wired to the cranking battery (stereo, fish finders...) you would want more amps? So I don't know what "group" battery is in the boat now, it is the smaller one, so I assume since I don't want to replace my battery trays, is I get the largest MCA/CCA I can get in that size?

 

[Jim B]

Trep you most likely have a group 24 starting battery in there now. Most of them should have enough cca to crank your motor. As far as electronics go its reserve capacity that you want so you will be able to run them all day.



Personally i like a "dual purpose" battery for my starting battery. What i run is a Trojan 27tm, it has 630cca and a reserve of 160min. I can run all my stuff all day long, radio, wells, ff's and still fire up my 150xr6 no problem. They also make a 24tm that has 550cca and a 130min reserve. or the 24sm-1000 starting battery that has 850cca and 165 min reserve.



I highly recommend the trojan brand it will be the last battery you have to buy for a long time.

 

[TrepMan]

Hey Rich - Confirmed it IS the original Interstate battery!! How's that 7 years old before it died!!

 

[cq]

My Interstate's did not make two years.

cq

 

[cq]

My Interstate's did not make two years.

cq

 

[Larry Harp]

My OEM Interstate is still going strong in my 2001. Even when I was having trouble starting the motor and having to do a lot of cranking, it never wavered.



Harpo

 

[Jim B]

My original interstates didnt make one season. Both the cranking and trolling, the trollings croaked in like 3 months and the cranking battery i couldnt run my well pumps on auto cycle for more then two hours without killing it.....

 

[Rich Stern]

Hey Rich - Confirmed it IS the original Interstate battery!! How's that 7 years old before it died!!

It's my special recipe distilled water.



For $20 (cash, non-refundable), I'll clue you in.

 

[TOMMY RICH]

Out of probably 4 batteries in two boats and all Interstate's, I only had one that wouldn't hold a charge and lucky for me I have a Interstate wharehouse down the road, they replaced it with a bigger battery at no charge.

They may not be the best but, Interstate seems to back their products...at least for me.

 

[TrepMan]

Rich - you make it over to my lake to drive with the pro trim and i'll give you a 6 pack of home brew, thats worth WAY more then $20!!! LOL



Pat - You may have something there, as usual, my Original Interstate batteries in my 2000 tracker lasted 5 years, and if this one realy latested 7 years its because Rich (and the original owner) didn't run it in 4 ft chop on Lanier and don't fish the big lakes like St.Claire, Erie and such.



Oh well, off to wallyworld tonite to find the largest group 24 battery they have (large in cranking and reserve amps).



Trep

 

[Jim B]

Pat i agree with you to a point. I have never had a lesser quality battery like an interstate or everstart last more then a year ever. The Trojans i have now, 4 years and counting and still working fine.....



And i do run plenty of big nasty water too a lot. Places like Champlain, Lake Winnipesaukee, Sabago. All big lakes that get very nasty( Champlain is like the atlantic when the wind blows). Winni gets so busy with boats in the summer, the boat generated chop gives you 2+ footers that suck to run since they come from every direction( id rather run big wind generated rollers then this stuff).

 

[Stan Tallant]

Trep I replaced all three of my batteries at the beginning of the season with batteries from Walley World while on the road. So far so good. Here in the south I know if I have any trouble I can find a Walley World easily for a replacement.

 

[Tim m]

Trep....Your putting 2 much thought into this....Go to Napa and buy 3 new batteries...group 24 for cranking and 2 group 27,s for trolling