cranking battery wont stay charged!

[Crappie Greg]

replaced old cranking battery with a new one, cant even get a day of fishing in without draining it dry, the electronics and livewell pump are the only things being used when not starting motor, any ideas on what could be draining battery? never had this problem before

[BigRiverMarine]

What is reserve on the battery, and how many CCA's, and CA's?

[Crappie Greg]

dont know reserve but looks like 500 cca and 625 ca

[Crappie Greg]

original was 600 cca 750 ca

[BigRiverMarine]

original was 600 cca 750 ca

Get something with 1000+ CA, and 850+ CCA. A 31 series has more reserve than a 24 or 27 series.

Go BIG or go home!!!!

[mdperson]

My 40hp motor requires a 1000 CA and 750+ CCA. I believe that interstate and tohatsu were in cahoots when developing the motor. If it does not have this it will do funny things like trip codes, go into limp mode or worse not start. I do not run anything extra on my cranking battery. Just a little draw over the day will cause me to have to troll back to the bank.

Get something with 1000+ CA, and 850+ CCA. A 31 series has more reserve than a 24 or 27 series.

Go BIG or go home!!!!

[BigRiverMarine]

My 40hp motor requires a 1000 CA and 750+ CCA. I believe that interstate and tohatsu were in cahoots when developing the motor. If it does not have this it will do funny things like trip codes, go into limp mode or worse not start. I do not run anything extra on my cranking battery. Just a little draw over the day will cause me to have to troll back to the bank.

Tohatsu recommends a minimum of 850 CCA for their TLDI's.

[arkansasbowhunter]

Get the biggest you can get Greg. I think size 34 cranking deep cycle. That happened to me before I went bigger. That's why I carry jumper cables in boat lol. Haven't had any issues since went to biggest battery. You remember it happy on the cm classic on lake lee.

[delta_G]

Get a digital multimeter with an amps setting. Pull one battery cable and stick one lead to the cable and one lead to the battery post you just unhooked it from. If you read any amps with your other stuff turned off then you've got a parasitic drain or something shorted somewhere and that will drag the battery down.

[RCC]

Unless you've got something draining other than the 2 hds9s and the live well, I would think the new battery would hold OK. Did the new battery have a date on it? If it had been on the shelf a long time, the battery may be off the shelf bad. Either that, or you've got some other drain that you are unaware of.