24volt trolling motor

[SHickey]

Hello,

I wanted to look at a 24v trolling motor to put on the bow of my 19' Bluefin. From the picture the trolling motor looks like it was from the 80's and the seller did not mention the motor type.

I was wondering if someone could tell me if I can hook up a 24 volt trolling motor to a single 12 volt marine battery in my boat. I have 2 batteries with a battery switch that gives me the choice of Battery #1 , #2 or Both.

I don't know alot about these motors but it seems like most of the electric trolling motors I see on CL are 12v not 24v. I am not a serious fisherman and just want something to play around with when we are fishing along shores and narrow waterways.

Thanks

 

[Barnacle_Bill]

A 24V motor requires 2 12 volt batteries wired in series.

 

[SHickey]

I did pick up the 12/24 v "old school" Johnson trolling motor. It has a three wire cable and I was hoping I could connect the black wire to the motor block, the white wire to the Perko battery #1 post and the red wire to the 1&2 (both) post and be done with it.

Is this simple wiring solution recommended or are there more hoops I need to jump through to get the trolling motor working in 24 and 12 v mode? Should I install a 40 amp fuse in both the red and white wire to prevent surges?

Any help with this is most appreciated!!

 

[Silvertip]

As pointed out earlier, two batteries in "series" are required for 24 volts? Setting the battery switch to BOTH does NOT place batteries in "series" -- it places them in "parallel". If it did place them in series every electrical device on the boat would be fried. You cannot get 24 volts from your current 12 volt system.
You bought a 12/24 volt motor. Power it with two separate batteries and forget trying to charge all four of them from the engine charging system.

 

[SHickey]

Thank you Silvertip for the information. I have two batteries in my boat and I should be able to rewire them into a series this afternoon. I did see some previous posts with wiring diagrams showing how to hook up a 12/24 v trolling motor into a 2 battery series configuration.

Would it still be recommended to use a 40 amp fuse for each 12 v and 24 v power lines?

Lastly, would it be recommended to purchase a 3rd battery and use it exclusively for the I/O motor and leave the two series batteries to power the trolling motor independently and remove that connection from my Peko switch??

Thanks for your patience!!

 

[Silvertip]

I have the feeling you are not following this discussion. Yes -- can wire the two existing batteries to provide 12 and 24 volts for the trolling motor. Yes you need to protect both the +12 and +24 volt lines. But if you use those two batteries for the troller, what do you intend to use to start the engine? If you expect to wire the engine to one of the batteries, you had best take a pair of oars along with you as the troller uses a great deal of current and will discharge BOTH batteries leaving you two discharged batteries, neither of which will start the engine. And if you connect the motor across both batteries you will have 24 volts to the motor which will fry things. You could connect the two large engine battery cables to the same battery on which the troller ground cable connects but again -- you risk a no start condition due to depleted batteries. Use the two batteries you have for the troller and keep the engine on a totally separate (third) battery.

 

[SHickey]

Thanks again Silvertip for the advice. I obtained a third battery and I will use that battery exclusively for I/O motor operation. I wired the two trolling motor batteries in a series and the trolling motor works in the 12v and the 24v mode. I have the I/O battery on the #1 and did not connect the trolling motor batteries to the Perko switch because I wanted to make sure the trolling motor was working as it should.

From what I understand in your last post, I can connect the trolling motor battery that has the ground attached to it to my Perko switch #2 and that will allow one of the trolling batteries to start the I/O if necessary and that battery can be charged by the I/O when necessary. Am I understanding this correctly?

Your patience is most appreciated and Happy Fathers Day!!

 

[Silvertip]

That will work only if you connect the NEG terminal on BAT #2 to the NEG terminal of the I/O battery. That cable must the same size or larger than the those on the I/O battery. The same holds true for the POS terminal on battery #2 to the switch. Remember, if you use BAT #2 to start the engine the very high current draw would quickly fry small gauge wire. You do realize that because you are essentially combining 12 and 24 volt systems that it leaves you open to severe and expensive electrical damage should you screw this up, or if there is an accidental wiring mishap. It is always a good idea to leave these two systems totally separate. Besides, after a full day of fishing that troller battery probably would not start the engine anyway. Keep the engine tuned, know how to start it properly and you will likely never need to use the other battery.

 

[SHickey]

Thanks again Silvertip for the advice. I think my best option is to recharge my trolling motor batteries # 1 and #2 with my battery charger and keep battery #3 (I/O) completely separate from the other two.

The only time this may be problematic is when I am fishing in the Adk Mts and there is no shore power where we camp. If I do want to connect battery #2 to my Perko switch, I will be sure have my mechanic look over the set up to prevent a major failure.

Your patience is most appreciated!!

 

[Silvertip]

Recharging just battery #2 does nothing for the other battery in the 24 volt pair. You need a small generator to power your portable charger if you intend to camp in remote areas with no source of power.

 

[rynerice]

I'm going through the same problem. I have a 24v motor and a 12v I/O 4 cylinder main motor. I am wanting to figure out what I need to get to be able to charge the 24v through a inverter or something that can run off my 12v main? Is there such thing?

 

[Silvertip]

The "search" feature is your friend here. Someone posted a link to a device that has fully isolated grounds that allows charging a 24 volt series string from a 12 volt alternator. However, do you realize how long you would need to run the main engine to charge three batteries, two of which are likely deeply discharged?? No -- small solar panels are not the answer either.

 

[rynerice]

Would something along the lines of a 400 or 800 watt marine inverter with a 12v input to 115 outlet work with a Minn Kota trickle charger that has a 110 plug on it? I know it'd take awhile to charge but it might be an alternative?

 

[gm280]

Unless you know for fact that you need a 24 volt setup to accomplish what you are wanting. I say forget the 24 volt trolling motor and buy a good 12 volt trolling motor and then your battery selector switch can be used for either battery. A lot less maintenance and way less wiring issues. Especially if you really don't understand such setups... JMHO!

 

[rynerice]

If I was buying one I would. A guy I know got a new self deploying motor and gave me the one that he replaced Its basically brand new and is already set up with the ipilot and everything

 

[rynerice]

12v does sound a lot less complicating tho

 

[gm280]

12v does sound a lot less complicating tho

Well seeing how it was a freebie, you can just hook it up for running from only 12 volts and use it. There is nothing saying you have to use 24 volts. Of course you won't get maximum thrust, but unless you think you will need maximum output, 12 volts would make it a lot simpler... JMHO!

 

[Grandad]

(Did anyone notice this is a post from May last year?) But just to further the violation, a comment on using 12V on a 24V device. Cutting the normal voltage in half will cut the power (and thrust) produced by 3/4. Probably not a good solution.

 

[gm280]

(Did anyone notice this is a post from May last year?) But just to further the violation, a comment on using 12V on a 24V device. Cutting the normal voltage in half will cut the power (and thrust) produced by 3/4. Probably not a good solution.

Oh, my mistake. I should have seen it but I just replied without reading the entire thread. Sorry........... :sorry:

 

[Silvertip]

Yes -- me too. Why not just lock posts that more than six months old. This happens with way to much frequency. It takes up respondents time and server space. If an OP wants to re-open a post that has been closed let them start a new thread.