Calling on Silvertip: Trolling Motor Wiring Again

[KVH]

With the volume of information you've given all of us on this subject, with literally dozens of posts and graphics as well, we ought to be indebted. I am, for one, but I'm going to bother you one last time if you might be able to help. Since the facts are important, here we go:

a) Like new (but old) Evinrude '96 55lb Thrust Trolling Motor, bow mount, foot controlled;

b) Four Prong plug, '96 Stratos, 201 FS

c) New Batteries

d) Thight Clean Connections

e) Four red wires coming from the front to the batteries (trolling motor looks like two reds, a white and black)

f) 12/24 Volt Switch at the foot pedal

g) Batteries wired straight with no jumpers

Here's the problem: I have 12 volts showing in the plug socket holes at the bow. I do have two speeds, one for each of the 12/24 settings of the swith, and when switched to 24 volts the power is considerably greater than when at 24. So, I assume the switch is achieving 24 volts somehow. However, the 12 volt setting seems way too weak, and when I use the Trolling Motor in the water, the power is extremely weak at both 12 and 24 volts. A total drag. At the 12 volt setting in the water, it's like a child's toy. And at 24 it's nowhere near how it was originally.

Out of the water, the speeds and power (just playing with it) seem strong only at the 24volt setting. In fact it seems stronger than when it drops down into the water for use.

My questions probably aren't easy ones: Could I still have the wires incorrectly set if I have two speeds at the switch? Does that necessarily rule out a wiring problem? Is there a way to tell which wire is which when I check the wiring? Heck, they're all red at the batteries.

Thanks, Silvertip, and sorry for the bother. You've already written an encyclopedia on this topic.

I'd of course value the opinions of anyone else knowledgeable to the issue and who might care to respond.

KVH

 

[wifisher]

Re: Calling on Silvertip: Trolling Motor Wiring Again

It sounds like you are not getting enough amperage to the motor. What size wires are you using, and are you sure that the connections are all tight and clean?

 

[augnmike]

Re: Calling on Silvertip: Trolling Motor Wiring Again

Yeah, I am on my fourth "last time" bugging Silvertip, I just resolved myself to the fact that he will have to get a restraining order.

 

[Fed up]

Re: Calling on Silvertip: Trolling Motor Wiring Again

If you batteries have no jumper, I do not see how you can ever get 24 volts out of the system.

What I think that you are seeing is only 12 volts when you have it switched to 24 volt. While switched to 12 volts you are not clearly seeing 12 volts.

 

[Silvertip]

Re: Calling on Silvertip: Trolling Motor Wiring Again

If you batteries have no jumper, I do not see how you can ever get 24 volts out of the system.

What I think that you are seeing is only 12 volts when you have it switched to 24 volt. While switched to 12 volts you are not clearly seeing 12 volts.

You get 24 volts with the 12/24 selector switch on the motor. The batteries are two separate 12 volt feeds to that point. Therefore the need for a four prong plug. 12 volts on each pair.

 

[Silvertip]

Re: Calling on Silvertip: Trolling Motor Wiring Again

OK -- hang on while the ride starts. You said you have four red wires (two from each battery) going up front to the receptacle. That alone tells me someone has mucked with the wiring as the boat manufacture did not do that. If they did they should be flogged. So -- one battery at a time, follow the wire from the positive post to receptacle and make yourself a diagram of plug so you can indicate which terminal that wire goes to. Then do the same with the wire on the negative post. If you don't want to replace the red (negative wire) with a black wire, at least put a wrap of black electrical tape around it at each end so YOU know which wire is which. Then do the same thing with the second battery. Since you have two reds, mark one of those with a zip tie on both ends so you can identify it. With me so far??

Now that you know which terminals on the receptacle are pos and neg and from which battery, lets move to the troller harness plug. The two reds are +12 volts each and must match the two +12 volt terminals on the receptacle. Likewise the white and black must match the two ground termnals on the receptacle. What you really need to dig into is that the red/white and red/black pairs are properly matched which is where I think the issue is. If the black wire in the motor harness connects to the negative of battery #1 but is really supposed to connect to battery #2 (because it is the mate for the red wire from battery #2) you can see where this would cause issues. I do not have a wiring diagram for that motor and am not familiar with it but I am positive the wiring from the batteries to the receptacle is correct except for the red negative wires which should be black or at least one black and one white. One way to determine which troller ground and positive wire are a pair is to stick a pin into each wire. Then use a voltmeter to check between one red wire and the white. If no reading, the other red and white are a pair. That also tells you then which red and black wire go together. You can now match those to the receptacle. If this is what you have, then there is a problem with the motor. If you need to change wiring at the plug (or the receptacle) to get the correct match, then the motor should work. If not, again you have a motor issue. Hope this helps.

 

[KVH]

Re: Calling on Silvertip: Trolling Motor Wiring Again

I must have hit the wrong button because I thought I'd replied to the last post. Anyway:

Yes, Silvertip, that was helpful. I'm convinced I've got everything correctly wired, and I've got 12 volts at two of the plug points, and at both inputs to the 12/24 switch when it's switched to 24 volt mode. Therefore, I'm beginning to conclude everything is OK with wiring. I just can't think of anything else, except the motor itself.

The motor seems very strong in 24 volt mode out of the water, and I do have two speeds. My guess is that when in the water something must be changing, shorting or something, because the power really is poor when I lower the motor into the water.

I'm also not seeing anything wrong with the prop, though it is quite old and has a few dings.

Any final thoughts? I'm about out of ideas after patiently messing with this for quite some time.

Thanks again for all the help.

 

[Silvertip]

Re: Calling on Silvertip: Trolling Motor Wiring Again

Here is a simple test of power -- but by gosh you better have your leather gloves on and a very stout bath towel to work with. Wrap the towel around the prop one complete loop and then hold the two ends away from the circle created by the prop diameter. Have someone quickly pulse the ON - OFF switch with the power set to the fastest speed. If that motor is up to snuff it should nearly jerk or possibly jerk the towel out of your hand. If the motor stalls easily, then it has an issue. GEEZ -- be careful doing this. Props are sharp.