need help w/24volt battery

[beantown]

I have two 12 volt deep cycle batteries which I understand how to run parallel to make 24 volts for my trolling motor. BUt can I still hook up my main engine to the batteries or do Ihave to have a third battery? Also I am looking into buying minn kotas battery charger that hooks up to my main boat engines alternator so I can charge the batteries on the fly. But the minn kota charger is only for 12 volts hoe do I hook it up? I leave this boat in the water and have no shore power. So this charger would be ideal. Any help would be appreciated. Thanks

 

[Zum]

I think I can help alittle:
2-12 volt batteries in parallel still gives you 12 volts(+to+;-to-)
2-12 volt batteries in series gives you the 24 volt(+to-)
Read this link,theres a good picture there for what your thinking:
https://www.tinboats.net/forum/viewtopic.php?f=5&t=3454&start=0&st=0&sk=t&sd=a
Ummm as far as the motor keeping your trolling motor charged,I don't think it's going to happen,not enough output.If you had a seperate battery as a starting battery it probably would keep that one charged but not the trolling batteries,sorry i think you need shore power for that.
Someone please correct me if this is wrong.

 

[redbug]

you can use a 24 volt 2 battery system to start your gas motor.
for your trolling motor connect a jumper from the positive of battery 1 to the negative of battery 2 that will give you 24volts from positive of battery 2 to negative of battery2
for your gas motor just hook up your leads to battery 1
the minn kota charger you are looking at will charge your batteries and is available in a unit that will work on a 24 volt system.
the way they work is after your starting battery reaches 13.1volts it switches over to your trolling motor battery. you need to run your gas motor for a while for this to have any affect.

 

[beantown]

thanks for the replies. I think i am going to use three batteries. I found this link tell me what you guys think,should i get it?
https://www.emarineinc.com/products/inverters/trollbridge.html

 

[Zum]

Sorry,I'm of know help,I didn't even think you could charge a battery of your outboard(fully).
How long do you have to run your outboard?Probably depends on the size outboard?
Let me know how it works out for you.

How many amps is there out of an outboard?I think a 175hp only has like 8amp,running two batteries in parallel it would take aleast 24hours to fully charge?I'm so confused..

 

[redbug]

i have a yammaha 225hpdi that has a 45 amp altenator so it will charge your battery but you will need to run it for a while before you starting battery is fully charged and the unit kicks in
if you are only making short (15min) runs with your gas motor I would save the money because the inverter you are showing will not kick in in that short run.

 

[Zum]

Wow didn't know the amp was so high.
That would be cool,long run in it would be topped off.
Hook it to the truck on the way home and know need to plug it in when home.