Astro Trolling motor - no power

[davescountry]

I hope you all can help otherwise I am likely going to be in severe trouble with my wife. Yesterday I bought a boat off the internet. It is a 1998 Astro 1800 F/S. I went for the test drive and managed to test everything but somehow forgot to test the trolling motor.

It has a bow mount motor, Minn Kota 24 V. The owner primarily used this for skiiing and when I emailed them, said they hadn't used the TM for quite some time but worked fine last they tried.

It seems like it is not getting any power at all. I tried it with the key on and off. I charged the batteries and my meter says I am getting about 13 volts each at the posts. When I test the back of the plug up front, it reads 0 on one and something like .5 on the other.

Is this something ridiculous like I don't have a switch turned on right? I would imagine there should be heavy duty fuse somewhere but haven't seen it yet.

Here is the ridiculous part and why I am a bonehead. I got rid of my lst boat for this one thinking it is more family friendly. I have a daughter that is 2 and figured her first boat ride would probably be a trolling motor only ride since I think the main engine will startle her. So, I can't believe I did not check the TM when I got this. My intuition tells me this is probably not too major but just don't know where to look.

 

[Silvertip]

Re: Astro Trolling motor - no power

Since this is a 24V motor, you need two 12V batteries connected in series. That system should look like this:

Check the connections on each battery to make sure they clean and tight. Make sure the circuit breaker has not been tripped. It may have a button on it to reset it, or if there is a fuse installed it will be close to the battery and may also be blown. You should measure 24 volts at the connector. If you have 24 volts there, then check the plug on the troller motor cable. They can get corroded and not make good contact.

 

[davescountry]

Re: Astro Trolling motor - no power

Let me see if I can describe what I am seeing. I should also add, this is a 24/12 volt motor with a three prong plug up front.

When I look at the batteries, this appears to be how they are wired.

Battery 1 - Neg seems to be the main neg. Positive terminal loops to neg on battery two. Positive also has a wire that feeds in to the wiring harness.

Batter 2- Neg is feed from positive in battery one. Positive feeds up into the wiring harness.

All three feed in to a wiring harness of sorts. About 6 inches in, there appears to be some type of relay of fusable link. The wires are spliced into something that feeds up to a clip, then back down and up towards the front of the boat. I tried to test power at that point and was not registering any, which makes no sense, but will give it another try .

If I take my meter and run positive on battery 2 and negative on battery 1, should I be reading 24 v?

 

[Silvertip]

Re: Astro Trolling motor - no power

See what happens when we get only half the story? Here is what a 12/24 system looks like. And please indicate whether or not you have a 12/24 switch or a Charge/Run switch in the vicinity of the troller receptacle. This is what you have if the MOTOR has the 12/24 selector switch.

And this is what you have if you find you actually have four wires going up front.

 

[davescountry]

Re: Astro Trolling motor - no power

Ok, I am feeling more educated as I go here so maybe can be more complete with things. My last boat was such a mish mash of self engineering, I probably am not used to a boat that is actually designed well.

Base on the above diagram, I really crawled down in there to get a close look and make sure I wasn't missing anything. My configuration does appear to be wired correctly based on the 3 wire diagram above for 24/12 volt.

I don't see any switch near the trolling motor plug up front. There is a toggle switch on the trolling motor itself. In another red face moment, I listed this as a Minn Kota (thats what my old one was). This is a Motorguide. For reference, it is a hand control TM with two "hot foot" controls mounted directly into the deck.

I When I was double checking the batteries, I did actually find some labels on all of the cables. I cleaned them off and they pretty much mirrored the 3 wire diagram above. So, I think the batteries are wired correct.

The wires leave the batteries into a what I am calling a harness. Basically a black plastic sheath that protects all the wires. Thats probably not the correct term.

Before the wires leave the battery compartment, each positive feed wire goes up to some type of plug. I have a pic attached below but it looks like the positive feeds in and then back out of the plug. I don't know but are these fuses of some sort?

I checked the positive feed into these plugs on both positive wires and ws getting 12 v readings on each. I basically tested with my meter right below the plug and then back to the negative post.

I also did the same on the wire back out of the plugs and got basically no positive reading on either. So, it would seem this is where I have power loss.

 

[Silvertip]

Re: Astro Trolling motor - no power

Raise the tab and pull the cap off the black housing (don't pull on the wires). You should not be surprised to find a fuse in there. The three-wire system is what you have.

 

[davescountry]

Re: Astro Trolling motor - no power

Well, now I feel more silly than before. I kept unplugging those thinking that something in the cap portion was supposed to be making connection. As it turns out, there were no fuses in either.

I had a 20 and a 5 sitting right there, so I through those in for a quick test and sure enough the motor works fine. I am sure those are not the appropriate Amperage though.

Any idea of what each of those should be runnning? These appear to be what I would call standard auto size blade plugs, not the larger plugs used for say a 35 or 50 amp fuse.

 

[Silvertip]

Re: Astro Trolling motor - no power

Minimum 30A and even that might not hold on the high speed setting. Do those fuse holders look like they were factory installed or added on? A 40 or 50 amp is typically used but that depends on the power draw of the motor.

 

[davescountry]

Re: Astro Trolling motor - no power

I'd say pretty positive they are factory installs. They have some labeling on the wires heading in to each that are similar to other labeling.

I had some 30A and threw those in. They seemed to handle all settings based on a quick test. I will see what happens, but at least I know now what the problem was overall.

I figured this was something simple and that I just didn't have the intuition or expertise to figure it out. Thanks for all the help.

 

[mattsboat19]

Re: Astro Trolling motor - no power

Hi my name's Matt and I have the same problem as this guy but my switch says charge/run and my boat is an astro 1990 19fs. I have it right now with 2 of the leads that would work for me, but when I hook 24v trips the breaker and wires are hot when I run it on full speed for a little while. And when the breaker cools, I can still run 24v but not at full speed, and it doesn't trip. The wire diagram that is on my door where my batteries are doesn't work the way it's shown. I'm really you can give me some good info on this subject.

See what happens when we get only half the story? Here is what a 12/24 system looks like. And please indicate whether or not you have a 12/24 switch or a Charge/Run switch in the vicinity of the troller receptacle. This is what you have if the MOTOR has the 12/24 selector switch.

And this is what you have if you find you actually have four wires going up front.