how to switch battery power to trolling motor

[commanche]

hello, need advice.. i have battery for my trolling motor and 1 for the mercury outboard..is there a way to use battery from my mercury to power my trolling motor after that battery gets low..

something like a switch than can put power from that battery over to my trolling motor ?thanks

[zooker]

if it gets low?? are ya charging it to start with? if so ya probly need a new battery with a bigger reserve. a 31 series or so..i fish for 8-10 hours at times and have no problem with the battery geting low-i use optima's-they do make a combinder and bridge. but this is not a switch that pulls from the the cranking battery.it is a BAD idea to pull from the crank battery..



zooker

[betursweetbass]

(said in yoda style)

"Agree with Zooker, I do, you need a new Trolling motor battery, you do not want to draw power from the cranking battery".

[Jackl]

COMMANCHE,
Have you considered a rectifier that charges your trolling motor battery off the big motors charging system while you are running down the lake? I hae a fishing buddy that has this hook-up on his biat, and also charges his boat batteries off his tow vehicle while driving to and from the lake. He never has to use his on board charger to keep his batteries charged!

JackL

[zooker]

Originally Posted by Jackl

COMMANCHE,
Have you considered a rectifier that charges your trolling motor battery off the big motors charging system while you are running down the lake?

this is what i was refuring to just could not remember the name..

zooker

[commanche]

i use my trolling motor on small lakes here in pa.you cant use your mercury gas motors..

after i get down lake and try to get back, my trolling motor battery is wore out..

there sits my mercury battery fully charged..but i cant use it to get back.

i thought they made some kind of switch that i could switch over to my mercury battery to use on my trolling motor?

[Rebbasser]

Commanche, there is a battery switch you can get at places like Bass Pro:

http://www.basspro.com/servlet/catal...=SearchResults

I fish a similar lake here in South Texas. If you have the room I'd get a second battery. the problem with using your cranking battery is it is not designed for the low, steady draw like a deep cycle. For the cost of the switch you can get a deep cycle from WalMart for about the same price. Then all you have to do is switch the cables-put clips on the cables rather than the eyes you screw on to the terminal and you are good to go.

Welcome to the forum, BTW!

[commanche]

thanks for info..i did have 2 batterys for trolling motor, they were close to 100 dollars each..then i had to replace them all time and weight in boat..

i thought going to 2 batterys, the mercury gas motor one and trolling one would save me weight and money..

i did not know that about the cranking mercury battery not being deep cycle, yes, that could be problem on switching..

no way i can operate with just 1 battery ,i cant make it back in wind and i am draining battery to low, thats not good from what i read..

my trolling motor is 67 thrust and 17 ft basstracker fiberglass boat..

that switch is 28 dollars, i cant find battery anywhere near that price in deep cycle battery at wal-mart..

but, i agree, maybe that would not be good idea on the cranking battery being used..i hate replacing these batterys every 2 years or so, they just dont last..wal mart battery was my worst one i had..sears was not to much better..

interstate batterys are betterr but cost arm and leg..

well, keep ideas comiing, thanks

[commanche]

do most of you carry 2 batterys for your trolling motor plus the gas motor battery?if so, how big of batterys do you need if you get 2 batterys..

i have basstracker 17 ft with 90 mercury on

[1FASTLASER]

Welcome to the forum You posted that you had a 67lb thrust troller. I am not aware of a trolling motor that has that high of thrust and being a 12v only. You should have 2 batteries already. And if thats the case that indeed you do need 2 batteries for that troller to last for a day of fishing. A 24v system draws less amps on 24 than a 12 does. Look at your troller again and make sure. I STRONGLY suggest leaving the crank battery out of the loop. I promise you you will kill that battery as well ifn you start using it for the 2nd battery. A marine starting battery is a TYPE of deep cycle and DEFINATLEY not intended for use on a troller. A troller draws amps for LONG periods of time and needs a battery that is built for many cylcles. A starting battery is designed for some periods of being drawndown BUT it is to be brought back up ASAP to a full charge state.

[commanche]

i guess its 2 batterys, i have been trying to cut down on my costs for batterys and weight.those new light batterys would help on weight but cost is too much ,i feel.

thanks for advice,keep it coming.

[HOG Ranger]

I take my boat to some electric only lakes and run my trolling motor for a full day. I am using a Minn Kota #74 24 volt and always have plenty of power left to get her back on the trailer.

If your trolling motor is only 12 volt using (2 in tandem) decent batteries should be more than enough for a days fishing.

I know batteries are expensive but it is a lonely feeling when you can't make it back to the dock. Spend the money and have a worry free day on the lake.

[1FASTLASER]

WORDS OF WISDOM Hog Ranger. Very well put.

[commanche]

Originally Posted by HOG Ranger

I take my boat to some electric only lakes and run my trolling motor for a full day. I am using a Minn Kota #74 24 volt and always have plenty of power left to get her back on the trailer.

If your trolling motor is only 12 volt using (2 in tandem) decent batteries should be more than enough for a days fishing.

I know batteries are expensive but it is a lonely feeling when you can't make it back to the dock. Spend the money and have a worry free day on the lake.

you brought up good point to discuss..is there any advantage to hooking 2 trolling batterys up TANDUM as you said..i have been running the 1 battery,then i reach down and switch cables to other to get home..

[commanche]

2 questions..first is it better to run the 2 ,12 volt batterys in tandum..i have been running 1 then i open the lid and switch batterys..

next, is it better to charge 1 battery when you get home or if tandum,can you charge both at same time..

[Rebbasser]

Commanche, if you can run them in tandem, great. I tried it with my old 12V and it kept blowing the fuse so I just switched batteries as needed.

If you do run them in tandem hook them up parallel: + to +, - to -.

[HOG Ranger]

Yes, they must be hooked up in parallel if you go that route as Rebbasser posted. When I had a 12volt system I always used them in tandem so I couldn't answer which way gives you more battery life, maybe it is worth a test to get the most time on the water. I can tell you that if they are hooked up in parallel they are easier to charge because you don't have to switch batteries.

[lizardsrule]

I realize cost is a issue for you. But either the battery/batteries you have now aren't up to snuff, or like already mentioned you are using a 24 volt motor with a 12v setup. If it is in fact a 12 volt, then perhaps you should upgrade you trolling motor to a 24 volt system, or even a 36 volt if you are fishing electric only lakes that often. Not saying you have to tommorrow, but in the long run it will save you money. If it's electric only then the weight of the batteries is completely overshadowed by the power and longevity you get. It doesn't matter how fast you can get up on plane in a electric only lake. What JackL recommended won't be of any use, since you aren't supposed to even crank it up(other than possibly loading and unloading your boat). I've been on lot's of different boats, and the only time the batteries weren't good for a full day of hard fishing is when the either weren't charged up properly, or they were bad. Is there other things you are running off of those batteries? Such as aerators, lights, depth finders? Minimize what is being used by the trolling motor, as in nothing but the trolling motor. However I would also recommend a gel cell battery that never needs watering. That IMO is just one more area of failure and loss. One other possible area of concern is your charger. The charger could be not doing it's job properly. And if you can put the batteries on the charger immediately after fishing, do so. And a trickle/2 amp charge is better than a fast charge in helping the life of your battery.

Lizards

[commanche]

Originally Posted by 1FASTLASER

Welcome to the forum You posted that you had a 67lb thrust troller. I am not aware of a trolling motor that has that high of thrust and being a 12v only. You should have 2 batteries already. And if thats the case that indeed you do need 2 batteries for that troller to last for a day of fishing. A 24v system draws less amps on 24 than a 12 does. Look at your troller again and make sure. I STRONGLY suggest leaving the crank battery out of the loop. I promise you you will kill that battery as well ifn you start using it for the 2nd battery. A marine starting battery is a TYPE of deep cycle and DEFINATLEY not intended for use on a troller. A troller draws amps for LONG periods of time and needs a battery that is built for many cylcles. A starting battery is designed for some periods of being drawndown BUT it is to be brought back up ASAP to a full charge state.

why i said i had a 67 thrust on my nitro,that is wrong,its a 54 thrust ,12v motorguide..

i went and got another battery,so now have 2..thanks for help.