Charger/battery Problem?

[jessejames556]

I have two Optima deep cycle marine batteries and a starting battery for my motor in my boat I recently purchased used. I've noticed the life of the Optima batteries hooked up to my trolling motor and fish finder may be on the tail end of their life. They last me all day when coming off of a fresh charge, but they do not appear to hold a charge. I'm not sure what is acceptable in terms of loss of charge over time in storage, but my batteries are usually completely dead one week sitting after being fully charged. I have an onboard battery charger for all the batteries, but due to storage needs I can't have it plugged in at all times.

 

Last week I left the boat charger plugged in after I parked it. I returned one week later and noticed that the on board charger had a green light for fully charged, as it should be since I left it plugged in. Well I take the boat out and the all items running off the deep cycle batteries are dead..the trolling motor turns the prop maybe 1/32 of a turn and stops. The fish finder beeps when turned on but does not have enough juice to show anything on the screen. The motor battery is ok but of course that's a different type of battery.

 

I know the batteries aren't great, but when left plugged in, they shouldn't be completely dead...So:

 

1.  is it possible that the charger is able to conduct an immediate charge but fails to kick into maintenance mode as it should be doing? The light on the charger indicates the batteries are 100% after a week of sitting, but if I unplug it and plug it back in, it shows red again for charging/not fully charged.

 

2.  Also, how long should I expect my deep cycle charge to last when sitting in storage unmaintained by charger?

 

[Kevin22]

A typical battery will draw down to 70% or so after 6 months of sitting. 

 

You either have bad batteries or a ghost draw. I'd guess you have both, the ghost draw keeps dragging your batteries all the way dead which has ruined them. 

 

On all chargers, when you unplug and replug it will go through the charging cycle again for 5-10 minutes. 

 

I am a little confused though. You talk as if you have multiple batteries for  your trolling motor, which would suggest a 24v system but then you also have your electronics wired to the same batteries? Not good. 

[jessejames556]

Wow, then I definitely have a problem...

 

And when I unplug and re plug in it definitely takes long than 10 minutes...Especially if it has been sitting for a week.

Can you expand on why I shouldn't have my electronic(s) hooked up to my 24v system?

 

[Kevin22]

If you have the electronics wired correctly you can put 12V through the electronics off a 24V system. That is okay. But do it wrong and you will fry them. BUT, even with the electronics hooked up correctly you are draining your batteries unevenly. One (the one with the electronics) will drain quicker than the other, and your 24V motor is only as good as the weakest battery. It will shut off when the weakest one drops below 11.2V

 

Mine just sat for 2.5 weeks at the shop getting the motor worked on, when it came home I plugged in the TM batteries and they were back to 100% in about 15 minutes. It might have been sooner, but when I went out 15 minutes later they were green. 

[jessejames556]

Well then I'll definitely replace the batteries..do you have any suggestions for the electronics and where I should run them from? I'm not sure how well/long a 50lb TM would run off of 12 volts if I were to stop running a 24v system. I'm ignorant to batteries unfortunately..thanks for the responses

[slonezp]

The only thing on the TM batteries should be the TM. Do you unplug the TM during charging and when not in use? Put your graph(s) on the starting battery

[Long Mike]

Kevin is right.  The only thing that should be hooked up to your TM batteries is your TM.  If your TM is only a 50 pound thrust, then is suspect that it is a 12 volt motor and your batteries are connected in series.  As you have your electronics connected to one of the batteries, it will draw more current than the other, and will reduce the life span of both.

[jessejames556]

Ok, I wasn't sure if it was ok to have the fish finder on the starting battery. I'll do that.

yes I do unplug the trolling motor when not in use. I hope to just replace my TM batteries.. I assume that with new batteries and swapping my electronics, my charger will be able to get the job done.

[slonezp]

Well then I'll definitely replace the batteries..do you have any suggestions for the electronics and where I should run them from? I'm not sure how well/long a 50lb TM would run off of 12 volts if I were to stop running a 24v system. I'm ignorant to batteries unfortunately..thanks for the responses

It won't run correctly, maybe you misunderstood what Kevin22 was stating. Your electronics are 12v. Apparently they are connected to one of the TM batteries. This will cause extra drain on one of the two TM batteries. Think of the saying a chain is only as strong as it's weakest link. If you drain one battery more than another, you have a weak link. When buying batteries, the "group size " is the physical size of the battery. The "reserve capacity" is how long it will last. The higher the reserve capacity, the longer the battery will last(also more expensive).

 

Do you have a stereo in the boat connected to the TM battery's? A stereo is a constant drain on the battery. Same thing with a Power Pole

[Kevin22]

Take your batteries to autozone or any other place that does free checks. They will be able to tell you if they are good or not. 

 

It sure sounds like you have something that is not shutting off completely, that is called a ghost draw. Even when everything is turned off, something is using juice and draining your battery. 

 

Are all of your electronics, livewell, dash, everything connected to one lead that runs to the battery? If so, wire in a master switch to that positive line. That way when you are not using the boat you can flip the switch and kill everything completely so nothing can take any juice. 

[Long Mike]

Kevin, once again I agree.  The Master Switch was exactly what I needed.  I've got so much stuff hanging off the cranking battery, (i.e. bow and stern electronics, side scan unit, Sirius weather receiver, GPS receiver, all the stuff on the console, NMEA 2000 network, LED hatch lighting, and an alarm system for the hatches) that I decided to install a Master Switch.  Now I know that I have only one "ghost" drawing down my cranking battery, and that is the alarm system; and I have a hidden switch that can turn that off too.

[Way2slow]

A couple of things I might suggest.

First, I think Long Mike made a slight typo that didn't get caught. Yes, it's a good chance the 50# TM could be a 12 volt motor but with a 12 volt system, the two batteries would be connected in "Parallel" not in series. In parallel, the two batteries would only produce 12 volts, but twice the amp hours of just one battery. In series they would produce 24 volts at the same hours of just one battery. If it is a 24 volt system, the electronics and accessories can only be connected across "ONE" battery. If they accidently got connected across both, it will fry anything connected to them.

Second, as mentioned, all electronics and accessories should be running of the cranking cranking battery, not the TM batteries.

Before spending bunches of money on new batteries, you should do a little simple trouble shooting and maintenance. I would start by removing all cables (one at the time since you are not very familiar with what you are doing" and clean each cable and battery terminal until it's bright metal. If you have wing nuts, tighten them with pliers but replacing them with stainless steel hex nut's are better.

Since you don't have the knowledge of how to use a meter to check amp draw, but you do need to get some sort of digital volt meter. Fully charge the batteries, then disconnect one cable from each battery, let them sit a couple of days and check their voltage. They should read at least 12.6 volts and both should have approximately same voltage. As for the self discharge rate, that depends a lot on the type material the batteries are made of, cheap batteries generally have a much greater self discharge rate than good batteries, and Optima's are not cheap batteries. They actually should have a very low self discharge rate so even letting them sit for a couple of months should not cause much self discharge, unless one or both are bad.

One easy, simple test you can make to see if something is drawing on the batteries is to take a reading between the battery terminal and each of the cable's/wires you disconnected. If it reads battery voltage, that means there is something drawing current. It does not show you how much, but you should not be reading any voltage doing this test if nothing is creating a current draw.

Another simple test you can do with a volt meter is to place the meter across each set of battery terminals (the terminals, not the cables), with all the cables connected, and run the TM while watching the meter. The voltage should only drop a few tenths of a volt with no more load than you are putting on them with the TM out of the water. If it drops more than a volt, then that battery is probably bad.

[jessejames556]

I only have one fish finder at this time and the 50 lb tm...im extremely conservative with battery use and unplug the tm and the fish finder when not in immediate use. I dont have a power pole or stereo either.. So my setup should really be great in terms of extended battery use on the water.. My only issue is the aforementioned connection issue with my fish finder being hooked up to the tm batteries..other than that it sounds like I have bad batteries with the potential of a ghost draw

I notice that the voltage according to my fish finder drops .2 volts typically while the tm is engaged on the highest setting. It can be slow to recover too.. I definitely will switch my source setup immediately. Unfortunately I store my boat an hour away from home by the lake so some of these diagnostic tests requiring monitoring are near impossible. I also have a 6 hour trip to Tenn. Coming up for a weekend of fishing, so I need to get these batteries in decent enough shape to last two days of fishing here soon. I may just break down and buy new ones so I don't blow the trip.

[Long Mike]

A couple of things I might suggest.

First, I think Long Mike made a slight typo that didn't get caught. Yes, it's a good chance the 50# TM could be a 12 volt motor but with a 12 volt system, the two batteries would be connected in "Parallel" not in series.

 

Woops! Sorry. Brain fart.

[slonezp]

Woops! Sorry. Brain fart.

First sign of the apocalypse.

[jessejames556]

I'm going to have to look up how to run them in a series as opposed to parallel. My tm has a 12v/24v switch but I want to keep it at 24v when I switch everything over and install the new batteries

[kjfishman]

Moving the electronics to your starting battery as suggested is a good idea, Add a ground disconnect to the starting battery and even if you leave forget to turn off the electronics  they will all be off when you disconnect the ground. Your tilt and trim should be connected to the starter battery also.

 

You mentioned you had a 12v/24v switch on the trolling motor. You need to look to see if you have 2 or 3 wires going to the trolling motor.  The switch may or may not be functional. My friends Bass Cat has an older  TM that has the switch but it isn't functional.

[jessejames556]

How can you tell if the switch is operational based on the number of wires?

[Downeaster2010]

Now I am a fond user of Optima batteries, but you must understand that Optima marine batteries are not deep cycle,

and are only rated as a # 24 size, where many deep cycles are rated #27, 29, and 31.  Your Optimas should continue

to work fine for motor starting, but be poor for deep cycle applications, as they will drain quickly, and give poor

trolling motor performance.  Get some deep cycle batteries, and you will see a change.

[jessejames556]

Well according to optima's website, their blue top #24/#34 batteries are deep cycle and good for use on a trolling motor..but they try to sell it as a multi purpose battery that is equally useful for cranking up a motor...which makes me leery because, the way I understand it, deep cycle batteries should be used only for electronics and trolling motors..slow drain, not the sudden high volt cranking of an engine starting.

[james 14]

I had two Optimas on a used boat as well and had to replace them. Not that it had anything to do with them being Optimas but I did just go through this problem myself. Over the course of a couple months I had to replace all three batteries AND my charger.

 

You really need to get a voltmeter and learn to use it as this is the only way to figure out your problem. Brand new Optimas should be resting at 13.0 - 13.2 volts. Mine were at 12.57 and 12.72 and would get me through about 7-8 hours of fishing before they were toast. When I'd get home afterwards they'd be WAY low...like below 10 volts. You take this measurement by touching each wire of the tester to each post...it takes about 5 seconds. You'll also want to check the voltage with the charger plugged in. Depending on the voltage of the battery at the time you begin charging you should see the voltage go up to over 14 volts. If your batteries are not charged (as verified by taking a voltage measurement) and the charger tells you they're charged and you verify you're not getting more than a float voltage (that exact voltage depends on your charger) then your charger may be bad.

 

Other notes:

Severely discharged batteries will not always be recognized by your on-board charger and may require a boost charge with an external charger before the on-board charger will charge it...otherwise it'll just tell you the battery is charged.

Batteries that are left in a discharged state below 12.4 volts will begin to sulfate (they'll get damaged). Anytime you discharge a battery below 12.4 volts you are doing some form of damage.

 

My grandfather also has the 12/24v option on his 50lb TM. That motor is at least 15-20 years old. I was looking at his batteries just the other day and noticed they are wired straight to one battery and in series to the other. Basically you should have three wires coming from your TM. Let's say two of them are positive and one is negative. Both + wires will go to the + terminals and the - will go to the - terminal on the first battery. Then the + terminal of batt 1 will connect to the - terminal of batt 2. When you flip the switch it switches which + wire it's taking power from. If it's working correctly you'll know it right quick when you flip the switch on high power. Personally, I'd leave it on 24v the entire time due to the fact you don't want to draw one battery more than the other. You'll get more battery life on the trip AND overall compared to using the 12v setting.

[jessejames556]

I had two Optimas on a used boat as well and had to replace them. Not that it had anything to do with them being Optimas but I did just go through this problem myself. Over the course of a couple months I had to replace all three batteries AND my charger.

 

You really need to get a voltmeter and learn to use it as this is the only way to figure out your problem. Brand new Optimas should be resting at 13.0 - 13.2 volts. Mine were at 12.57 and 12.72 and would get me through about 7-8 hours of fishing before they were toast. When I'd get home afterwards they'd be WAY low...like below 10 volts. You take this measurement by touching each wire of the tester to each post...it takes about 5 seconds. You'll also want to check the voltage with the charger plugged in. Depending on the voltage of the battery at the time you begin charging you should see the voltage go up to over 14 volts. If your batteries are not charged (as verified by taking a voltage measurement) and the charger tells you they're charged and you verify you're not getting more than a float voltage (that exact voltage depends on your charger) then your charger may be bad.

 

Other notes:

Severely discharged batteries will not always be recognized by your on-board charger and may require a boost charge with an external charger before the on-board charger will charge it...otherwise it'll just tell you the battery is charged.

Batteries that are left in a discharged state below 12.4 volts will begin to sulfate (they'll get damaged). Anytime you discharge a battery below 12.4 volts you are doing some form of damage.

 

My grandfather also has the 12/24v option on his 50lb TM. That motor is at least 15-20 years old. I was looking at his batteries just the other day and noticed they are wired straight to one battery and in series to the other. Basically you should have three wires coming from your TM. Let's say two of them are positive and one is negative. Both + wires will go to the + terminals and the - will go to the - terminal on the first battery. Then the + terminal of batt 1 will connect to the - terminal of batt 2. When you flip the switch it switches which + wire it's taking power from. If it's working correctly you'll know it right quick when you flip the switch on high power. Personally, I'd leave it on 24v the entire time due to the fact you don't want to draw one battery more than the other. You'll get more battery life on the trip AND overall compared to using the 12v setting.

very informative, thank you. I will definitely buy a voltmeter. It sounds like my batteries are about at the same levels that yours were when you replaced them..i just hope I don't have to get a new charger as well.

[jessejames556]

James14, Just curious, did you replace your batteries with new optimas? I'm shopping around right now..the reserve rating on the optimas look good, but I'm wondering if there is better out there for the price

[james 14]

James14, Just curious, did you replace your batteries with new optimas? I'm shopping around right now..the reserve rating on the optimas look good, but I'm wondering if there is better out there for the price

 

No I didn't. I've had no problems with Everstarts in the past and that's what I went with. If I knew for a fact the Optimas would last twice as long I might would've paid twice as much (or more) but I don't forsee it happening as that would require 5-6 years of service.

[jessejames556]

No I didn't. I've had no problems with Everstarts in the past and that's what I went with. If I knew for a fact the Optimas would last twice as long I might would've paid twice as much (or more) but I don't forsee it happening as that would require 5-6 years of service.

 

Now when I looked at the everstarts, the reserve capacity rating is "114 minutes @ 1 A"..The Optima I'm comparing it to has a reserve capacity of "120 minutes (25 amp discharge)"...Are they being measured on the same scale? It seems to me that the Optima would crush the everstart on quality run time because it has a higher reserve capacity on a much larger discharge (unless I'm wrong in assuming the everstart is being measure on a 1 amp discharge scale as opposed to the Optima's 25 amp discharge scale)...Hope that makes sense...