Cranking Battery

[davidb104]

I'm looking for advice about my cranking battery. It's a marine cranking battery that I bought a year ago at O'Reilly's. It shows 860 cranking amps, but last week, during our annual trip to Table Rock, we had to "jump it off" 3 times. It's cranking a Mercury 200 4 stroke, and I was running 2 Lowrance 9" Carbons and one livewell. The alternator registers a 13+ volt output, so it seems to be adequate. Thoughts? Advice?

[jimsch]

860 seems low, what does the motor spec state? Mine is over 1000.

[BroWhoop]

20240428_203129.jpg
Ran my Phoenix fine!

[TKress]

When I added extra electronics last year I installed a battery over 1000 also. But for years previous I ran a smaller battery and no problems. You may want to have that battery tested and also check your charging system from the motor. If you do some searching too there are some pretty good threads on batteries from the board.

[ChooChooSnakeMan]

Livewell and the graphs I suspect are just too much for it. As mentioned get it load tested but I think you may need to invest in a more powerful battery.

[davidb104]

Thanks to each of you. I was accustomed to fishing by myself, keeping one Carbon going at a time, with no live well (I seldom keep fish). I never had a problem until last week at Table Rock, fishing with a buddy, running both Carbons and a live well. Guess it was too much of a load for the battery. I'm having a 1,000 amp battery installed, and hope that cures the problem. Thanks again!

[jimsch]

I installed a NAPA #7234 wet cell in mine last year. All day and some without a problem.

[DBolton]

Thanks to each of you. I was accustomed to fishing by myself, keeping one Carbon going at a time, with no live well (I seldom keep fish). I never had a problem until last week at Table Rock, fishing with a buddy, running both Carbons and a live well. Guess it was too much of a load for the battery. I'm having a 1,000 amp battery installed, and hope that cures the problem. Thanks again!

Don't hope. Get a properly sized AGM battery at minimum. 1000 CCA's and 200+ Reserve Capacity. Mercury recommends 975 CCA as the bare minimum and with accessories you need some size. Here are a some to consider:

X2Power BCI Group 31M 12V 100AH 1150CCA AGM Deep Cycle Marine & RV Battery - SLI31AGMDPM at Batteries Plus

Odyssey 31M-PC2150T-M 1150CCA Group 31M Battery (battsys.com)

VMAX XCA31-1400 Group 31 Battery. Made in USA. (vmaxtanks.com)