2 batteries or three?

[DocBob]

I purchased a used bass boat with a 24 volt troller system. The previous owner had 2 deep cycle batteries running the troller as well as all the electronics, and a third "starting" battery for cranking the engine. I need to replace the starting battery. Should I leave it wired this way, or can I save some weight by starting the big motor with one of the deep cycle batteries?<br />What does everyone else do in this situation?<br />Thanks,<br />Bob

 

[Luna Sea]

Re: 2 batteries or three?

Keep the trolling motor batteries separate from the starting battery. Minn Kota motors come with a warning about galvanic corrosion or something to that effect and say you void the warranty if you do so. I don't fully understand that but do know there's several other reasons as well, such as draining the starting battery, overworking your alternator, ect. Stick with the 3 batteries. I put a 36 volter on my Lund last year and was asking the same question. Do some searches in this forum. I've posted a bunch of general trolling motor links. Good Luck!

 

[imported_JD__]

Re: 2 batteries or three?

DrBob <br />Did the previous owner actually have the batteries wired in series producing 24 V or just 2-12 volt batteries piggy-backed? 24 volts will overspin your starter and probably fry your electronics. Manufacturers do not recommend connecting your fish finder to a trolling battery. If you run the trolling batteries down real low you may not have ample voltage to operate the electronics causing erratic readings and among other problems.

 

[DocBob]

Re: 2 batteries or three?

Thanks for the info. I'll keep the three batteries. I'm must apologize though. I re-read my post, and I noticed I misspoke. The troller batteries are in fact set up to run 24 volts, but the electronics were actually all run off the starting battery, not the deep cycle battery... I guess that does make more sense. <br />The reason I was asking, is two deep cycle batteries, a starting battery, a three gallon oil tank, and a 150hp outboard add a lot of weight to the back end of my little 17.5ft boat. When it's up on plane it screams, but the hole shot isn't as quick as it could be. Should I move the toller batteries closer to the front of the boat...since the motor is up there anyway. Shouldn't that help me get up faster?<br />Thanks again, and sorry for the confusion.

 

[imported_JD__]

Re: 2 batteries or three?

If you simply disconnected your trolling batteries and placed them up front approximately where they would be relocated it would certainly be an easy experiment. Another suggestion is to check your RPM at WOT to see if you're in spec. If you're significantly on the low side of the recommended range you could drop down a prop size in pitch.

 

[DocBob]

Re: 2 batteries or three?

Thanks JD_ ...I see I still have a lot to learn. I didn't really even think about the prop, not that that has much to do with how fast you go!!! <br />I'll have to check that out when the lake unfreezes.