Tolling Motor Power Issue HELP!!

[Jasay]

I have a 08 Triton TR21X HP. My trolling motor is a 36v Minn Kota Fortrex. I bought the boat back in March this year and have had no problems other than keeping my cranking battery charged due to leaving something on and running it dead while in storage.

I took it out a couple weeks ago and the trolling motor wouldn't work. I checked to make sure the off switch hadn't gotten flipped and the breakers weren't tripped. All was good. I checked the power coming in to the trolling motor to ground and only have 13v on one wire the other reads -0.3 v.

I do have a 4 bank maintenance charger that says all three of those are charged. Could it be reading 12 volts and being tricked due to them being on the series circuit? Could I have a couple bad batteries and need to disconnect them and check them individually?

Thanks in advance.

[wmitch2]

How are your batteries wired ? All three should be in series, Battery 1 Pos (Red) to the breaker/cut off, then to Trolling Motor, Battery 1 NEG to Battery 2 POS, Battery 2 NEG to Battery 3 POS and Battery 3 NEG to the Trolling Motor NEG (Black). There should only be 1 POS and 1 NEG wire to the Trolling Motor. The TM Plug should only be using the matching 2 wires. The Female plug should only be 2 wires also. If you have a 4 pin plug, it may have a RED<BLACK>WHITE>ORANGE wires. The Orange and white wires should be disconnected and taped off. Do the same in the bilge also. Hope this helps.

[Jasay]

How are your batteries wired ? All three should be in series, Battery 1 Pos (Red) to the breaker/cut off, then to Trolling Motor, Battery 1 NEG to Battery 2 POS, Battery 2 NEG to Battery 3 POS and Battery 3 NEG to the Trolling Motor NEG (Black). There should only be 1 POS and 1 NEG wire to the Trolling Motor. The TM Plug should only be using the matching 2 wires. The Female plug should only be 2 wires also. If you have a 4 pin plug, it may have a RED<BLACK>WHITE>ORANGE wires. The Orange and white wires should be disconnected and taped off. Do the same in the bilge also. Hope this helps.

They are hooked up in series like you mentioned but I have not found a plug. The wiring come out of the foot switch and down through a hole in the recessed pan in the floor.

[Bradrodfish]

Is there anything on the wires that go from neg to pos on the troll motor batteries. If so it is a breaker. Not sure why they use to do this, but it cause more headaches then anything. If you have them then get rid of them and just use a #8 wire between them. Check each battery for correct voltage. Should be around 12.8 on each. If it is anything lower than you have 1 possibly 2 bad batteries. No mater what charger says, still could be a bad battery. If they read correctly than pull them and have them load tested. Any auto parts store could do this.

[Jasay]

Is there anything on the wires that go from neg to pos on the troll motor batteries. If so it is a breaker. Not sure why they use to do this, but it cause more headaches then anything. If you have them then get rid of them and just use a #8 wire between them. Check each battery for correct voltage. Should be around 12.8 on each. If it is anything lower than you have 1 possibly 2 bad batteries. No mater what charger says, still could be a bad battery. If they read correctly than pull them and have them load tested. Any auto parts store could do this.

There is no "in line" breakers i have found. Although there are 2 bigger surface mounted breakers as well as 2 push button type breakers on the wall inside the compartment next to the main switches.

Disconnecting the batteries and testing them separately was going to be my next step unless I received different advice from here.

[catdude28]

Sounds like a homemade hardwiring job. Problem may be the connection under the recessed pan. I would access it and check for voltage there

[CatFan]

There is no "in line" breakers i have found. Although there are 2 bigger surface mounted breakers as well as 2 push button type breakers on the wall inside the compartment next to the main switches.

Disconnecting the batteries and testing them separately was going to be my next step unless I received different advice from here.

No need to disconnect them. Just measure the voltage on each battery. The series connection has no effect on charging or testing them. Still nominally 12V on each battery.

[Texas Larry]

You can measure each battery separately and should see 12V pos to neg. You can also measure all 3 in series from the first battery pos to the last battery neg and you should see 36V without disconnecting anything. There should be only one breaker on the 36V positive lead. Measure the output of the circuit breaker - it should read 36V from its output terminal to the negative post of the last battery in the series. If you don't see voltage there, the breaker is tripped or defective.

36 V Battery Diagram.jpg

[billnorman1]

Well. First off you had a dead battery. That's not good because some dead batteries don't like to be resurrected, they get flaky.

Apparently you only have three batteries in the boat and have a 36 volt T/M system. Turn the charger off. First, determine which battery runs the big motor. The negative terminal of that battery is ground, or Negative for the entire sytem. Firmly attach the negative meter lead to that terminal and check the motor battery. It should have nearly 13 volts after charging. Now put the posifive lead on one of the 2 leftover batteries and you should have 26 or so volts. Then go to the last battery and you should have about 36 or so volts on that positive post.

If you have all of the above checks you need to go to the wires going into the motor and check voltage with the motor "On" and the button depressed. I would be suspicious of the hard wire connection especially if it's wrapped in tape. Any hardwire connection must be able to stand about a 40 pound pull without coming apart.

[Jasay]

Found my problem. Thanks for the advice. There is no place for a plug at the front of the boat. It is wired to some kind of power bank with poles labeled ground, 12v, 24v, & 36v. From there it runs straight back to the batteries best I can tell. It may be hooked to a breaker on the wall in the battery compartment, can only know with more digging. Hopefully fixing this will fully fix my issue.

20210729_195625.jpg

[billnorman1]

Let me be the first. Apparently the bottom of your trolling motor is in or gets water in it. You need to stop that situation. Also, when there is power on wiring and it's in a water solution there is current flow between the wires which causes corrosion. Once you repair what looks like corroded connections, coat the connection with Liquid Electric Tape, then slide heat shrink over it and heat it with a heat gun to seal it.
I'm going on what I think I see in the photo. Solve the moisture issue, clean up the connection issues. If there was a way to add a connector, that would be your best solution, unplug it when not in use.

[Jasay]

Let me be the first. Apparently the bottom of your trolling motor is in or gets water in it. You need to stop that situation. Also, when there is power on wiring and it's in a water solution there is current flow between the wires which causes corrosion. Once you repair what looks like corroded connections, coat the connection with Liquid Electric Tape, then slide heat shrink over it and heat it with a heat gun to seal it.
I'm going on what I think I see in the photo. Solve the moisture issue, clean up the connection issues. If there was a way to add a connector, that would be your best solution, unplug it when not in use.

I did that yesterday afternoon. Its back working. Luckily the board wasn't fried. Definitely need to fix the drain in my pan and planning on sealing the connections with waterproof heat shrink.

[billnorman1]

I did that yesterday afternoon. Its back working. Luckily the board wasn't fried. Definitely need to fix the drain in my pan and planning on sealing the connections with waterproof heat shrink.

In my opinion the Liquid Electric Tape seals better because it absolutely touches/covers everything and when the heat shrink gets hot it squeezes out to make a positive seal, but, whichever works.