Problems with electric engine pontoon

[sudhimatpadi]

Hi I am a novice - have a electric pontoon (minn kota motor) that use in my community - which I purchased from a neighbor last year. Yesterday I in the middle of the lake it stopped - neighbor towed the boat. I thought I am out of power -and checked my batteries with a multi meter - all seem to be at 12 V (I have 3 batteries). Any thoughts on what could be the problem ...?

 

[ahicks]

Use you multi meter to follow the power. Start at the batteries, then to any fuses or breakers, to the reversing switch, and then on to the speed switch/control. Power could be interrupted anywhere. Shouldn't be that hard to figure out where.

Another thought, depending on how sophisticated the controls and the batteries are on your boat, it's possible there may be an LVC (low voltage cutoff) protecting the system from operating on too low a voltage. Fully charged lead acid batteries should read something closer to 13.5 volts. At 12v with no load on them, your system may be getting a low voltage signal when a load is placed on them (when the motor is turned on). With the boat tied to the dock, you could check that easily by running the motor at a low speed while checking the battery voltage. If you see something around 11v for instance with the motor running, you may back in business by charging the batteries.....

 

[JimS123]

A fully charged 12 volt lead acid battery should show 12.7 volts when there is no load on it. If a running engine (or generator) is attached, the charging volts should be about 13.4 volts. For an electric motor, it should be capable of running (maybe not well, but running) when the voltage drops to about 12.2 volts (about 40 or 50 % discharged). If the voltage drops to about 11.8 volts, nothing will run.

If your battery reads as i have indicated its not the problem. Otherwise, but you have a short somewhere or the motor has a problem.

 

[QBhoy]

A fully charged 12 volt lead acid battery should show 12.7 volts when there is no load on it. If a running engine (or generator) is attached, the charging volts should be about 13.4 volts. For an electric motor, it should be capable of running (maybe not well, but running) when the voltage drops to about 12.2 volts (about 40 or 50 % discharged). If the voltage drops to about 11.8 volts, nothing will run.

If your battery reads as i have indicated its not the problem. Otherwise, but you have a short somewhere or the motor has a problem.

Hi Jim...this isn’t totally perhaps the principles of it, I’d think. Although, as you say...much will depend on the type and features the motor may have.

my point is that it’s more about the load in terms of current it’s able to draw perhaps. Voltage isn’t indefinitely a sign of sure health in most cases. It’s usually the amps it can provide or be drawn from it (as long as the voltage is within the realms of sense obviously) even 12.5v and no load would be ok, if you’re thinking that way. But with the motor drawing from it...it may well drop to or most likely below the 12v should you put a meter across it.
if you think about a conventional petrol outboard for now...when the engine isn’t running...you’ll likely see 12.5 or 12.7 as you say....but press that power trim button and the volts will likely not stay in the 12’s for sure. It will be a similar principal with an electric motor.

in this case...if your batteries are known to be good...I’d maybe be looking towards the prop being fouled and throwing an overload cut out...or perhaps a fuse.

if you are not certain about the batteries...remember if you have the stereo and fridge on all day...that will be a no1 suspicion also.

 

[JimS123]

Yes of course, we could talk all day and still not figure it out since there is more to it than voltage. But, lets not overwhelm a self proclaimed novice with electricalstuff right at the beginning.

12.7 is what it should be unloaded. But that's not all. The SpG must match the voltage.

If the motor is turned on naturally the voltage on a running motor will drop. At MinnKota low speed maybe it will drop to 12.2. If it drops significantly below that then the motor is drawing more amps than it should (a motor problem) or the batteries won't hold a load (battery problem).

The OP said it seemed to be 12 volts. Well, if its 12.0 then the battery is nearly dead.

Bottom line is first thing is to turn everything off and check EXACT voltage and Specific Gravity. Walmart or any auto supply store has test tools. If data shows less that 12.7 and 1.277 the battery needs charging until it meets the specs.

 

[ahicks]

All due respect, I need to comment on the 12.7 fully charged standing voltage. I've had 13.5 or something close to that in my head for years, so I did some checking. Apparently, there's a couple of ways to look at this. I did a google search, and this came out at the top-

https://www.emarineinc.com/Marine-Ba...aintenance-101

If you read the text, you'll see this in a couple of different places:
"For a 12 volt liquid electrolyte battery at rest, a voltage of 13.2 -13.4 is normally appropriate."

If you drop down lower, you'll see a chart showing 12.7v is 100% charged, along with more info that should allow a pretty good stab at establishing a battery's charge level.

So which figure is right? Dunno. I'll leave that point to those with a higher pay grade than mine. Meanwhile, I'll try to remember something around 13v should be fine. -Al

 

[JimS123]

All due respect, I need to comment on the 12.7 fully charged standing voltage. I've had 13.5 or something close to that in my head for years, so I did some checking. Apparently, there's a couple of ways to look at this. I did a google search, and this came out at the top-

https://www.emarineinc.com/Marine-Ba...aintenance-101

If you read the text, you'll see this in a couple of different places:
"For a 12 volt liquid electrolyte battery at rest, a voltage of 13.2 -13.4 is normally appropriate."

If you drop down lower, you'll see a chart showing 12.7v is 100% charged, along with more info that should allow a pretty good stab at establishing a battery's charge level.

So which figure is right? Dunno. I'll leave that point to those with a higher pay grade than mine. Meanwhile, I'll try to remember something around 13v should be fine. -Al

All due respect, go back and read your article closely, paying attention to the HEADINGS above the sections.

The Chart at the bottom is correct. It shows standing voltage vs. % charge, for a battery that is not in use, has no load put on it, has not been recently re-charged and is not on a charger at the time of the test. That's the chart you need to use if you want to test a battery.

The 13.2 - 13.4 reference is in the "Multi Stage Battery Charging" Section. THAT is the voltage you want to APPLY to a battery when its fully charged and want to maintain the charge. 13.2 is the FLOAT charge RATE.

When you test your car's battery you should get 12,7 volts. If you're in your car DRIVING with the engine running (obviously the ALTERNATOR is running too) then you should see 13.2 volts because the battery is not IDLE, it is being CHARGED.

Hope that clears everything up. That is a very good article and it is no way contradictory. So, forget the 13 volts because its not fine.

Also, if you look at the chart, if in fact the OPs battery was at 12.0 volts, the battery had lost 75% of its capacity and was legally DEAD.

 

[Silvertip]

How about forgetting the voltage and current thing and go back to basics. Check the obvious -- did a circuit breaker or fuse open up? 2) Are the battery terminals (all of them) shiny clean and tight. Looking is not checking. Remove, clean and reassemble. 3) Did you inadvertently bump a power switch. 4) Are the batteries fully charged. Forget measuring them -- put them on a charger. Do these simple things and come back to us when you have other information. Otherwise -- all is speculation.

 

[Captain Caveman]

Mine stopped this summer. I knew that the batteries, fuses, and wiring were all in good shape. I took a wrench to the prop and popped it off. Sure enough there was a mess of someone else's fishing line wound around the prop shaft. Once removed my motor worked well again.

Check everything. My guess would be a fuse issue but check the prop too. Since it stopped in the middle of the lake, that doesn't sound to me like you ran out of battery.

 

[Scott Danforth]

is the motor full of water? BTDT...... just thru out the minn-kota in pieces.

it was running, then it was sluggish, then it quit. pulled off the boat, and as I laid it down, rusty water ran out of the TM. so I pulled it apart to have a look.