I charged my starting battery today the trickle charger said 77% charged. I know that the charging system on a boat needs to be charged some because the motor cannot do it all. I tested today at just a slight idle in gear I got 13.4 volts. I could not steer and hold the motor any faster. I think that sounds good. So maybe twice a week put a trickle charger on it? I’m embarrassed to say I just have not done it since I got it. My mistake to busy fishing.
I have a 115 Merc on the toon and never need to charge it other than off season.
Edit –
I run a helix 5 and 7 off it and the wife has the radio on for hours when she’s down at the dock. Never had a dead battery.
I put the charger on the starting battery every time I charge the trolling batteries. Boat has voltage gauge for the trolling batteries, but not the starter battery which also powers all the accessories.
I have an on board charger on my fishing boat. But our pontoon at the cabin with a 50hp and speed boat never get charged except in the off season.
I charge it once a month maybe. If I remember.
On board charger for my cranking battery too. Plug it in when done, unplug it when finished. I hook it up to a trickle charger about 3 times/season. It’s currently on year 6 so I may need to replace it at some point here but a load tester showed it’s still good.
I charged my starting battery today the trickle charger said 77% charged.
Are you “trickle” charging your motor or charging, then maintaining on a trickle charger?
I charge the battery with the trickle charger then after it is charged usually just maintain once a month I always trickle charge the trolling battery as soon as I’m done but that usually says 95% charged yet I just thought being down to only 77% charge was fairly low but again I have not trickle charged it since I got it 2 months
What else do you run off the battery. I run a garmin 93 and 73 off my starting battery. I also carry a jump pack but my battery has never been low. At least with the read out on my graphs
G-I’m curious, if the on board takes care of the cranker too, why put it on the trickler 3x a year?
G-I’m curious, if the on board takes care of the cranker too, why put it on the trickler 3x a year?
The trickle charger is more of a deep, slow recharge. Also, there are times during the season when I go a couple weeks without using the boat so I find it more beneficial to use the trickle charger. I also use the trickle charger after winter and before winter. Basically when the battery isn’t going to get used for a longer period of time.
I run a 7 inch screen, 5 inch screen, talon, and pumps/lights (if needed) off that battery in addition to starting the outboard.
The last time I attended the Sportsmens show I went to a seminar on battery care put on by reps from Interstate and Minnkota. They both recommended avoiding old style trickle chargers that deliver a constant 1 to 2 amps with modern batteries.
These are my notes from the seminar:
A discharged flooded battery should be charged with a smart charger back to 80% with 10 to 15 amps then the charger will decrease the amperage as the battery nears 100% then maintain it if left plugged in. You want it to get above 80% as quickly as possible without generating to much heat because sulphication and other issues develop inside the battery below that charge level. An AGM battery needs full amperage up to 85% capacity then have the amperage decrease on a slower curve than the flooded battery.
If the batteries are at over 80% charged you can use a low amperage smart charger like a Battery Tender to charge and maintain them but they recommended just using your on board charger or a smart charger.
They really stressed that old style trickle chargers were old technology for old style. batteries
mrpike have you checked to see if anything is drawing power from the battery when the key is turned off?
Good information Pat
Literally never done it and never had a problem starting.
I take it I need an ohm meter to check for battery draw? I will need to get one I just use a little minnkota battery tester. I run a helix 5 and a Lowrance hook 4 then lights and bilge pump which I have not used. To the best of my ability the charger I got says rapid charging up to 3 amp max it is a new one not an old one. I have had no issues ever with charging my trolling motor battery. I do have a master shut off switch which shuts the locators off my understanding is the I pilot is on this circuit as well when I bought it they put the cutoff switch in because they said it would draw power because of the GPS. I have been known to forget the switch as well. Basically I was just surprised at how low it was it read 12.2 volts before charging just the charger shows it had 77% charge I just figured the motor has not had enough time to recharge and I usually run the trolling motor all day then a quick jaunt to the landing when done. Meaning I don’t run the motor to much
Heres my take on it, and guessing on the battery, it is just barely big enough to start your motor and you have a graph or two, a livewell, and what else?? hooked to it?
A battery gives up its charge in amp hours, your motor and I am shooting from the hip here most likely does not have much more than a 8 amp charge coil on it.
lets do some country math here, battery loses 160 amps during the day of use.
to recharge those amps at 8 amps back into the battery when the motor is running full throttle,, 160 divided by 8 = 20 hours.
what a lot of folks dont realize is this, sure, you are charging at 13.4 volts, heck it could be 20 volts but those volts dont mean squat without amps backing them up.
so, if you are using more amps than you are putting back in guess what??
yep, low battery readings after a while.
you have to look at your trickle charger the same way, 160 amps used up and we hook 2 amp charger to it,,= now,80 hours to fully recharge !!
clear as mud aint it??
My point is,, more amps more often.
And don’t go overboard doing it pardon the pun.
Makes sense Iowa boy. I will continue to keep it charged up and keep a closer eye on things. I understand what you said and now the little hamster on my wheel started turning again. Thank you
Agree with iowaboy. I think a lot depends on how you use your main motor. Me personally, I typically fish small lakes and my main motor might only run for 15 minutes on a 4 hour outing. I run 2 Helix 7’s and sometimes the radio. I put a 10amp automatic charger on my starter battery after nearly every trip to top it off. Should really have a 3 bank onboard charger instead of the 2 bank I have connected to my trolling batteries.
Agree with iowaboy. I think a lot depends on how you use your main motor. Me personally, I typically fish small lakes and my main motor might only run for 15 minutes on a 4 hour outing. I run 2 Helix 7’s and sometimes the radio. I put a 10amp automatic charger on my starter battery after nearly every trip to top it off. Should really have a 3 bank onboard charger instead of the 2 bank I have connected to my trolling batteries.
Similar set up under similar circumstances. My starter battery typically shows around 85% charge when I get home from the trip. So I charge it after every trip. (along with the trolling batteries)
Interesting thread. I have a Pro Sport 3 bank charger on my boat. EVERY time I come home I plug it in until the green light comes on and then unplug it. Sometimes it stays plugged in until I leave in the morning and I have never had a problem w any of my batteries. Run a Terrova 80 lb,( Lund Impact 1775) w a 115, 9″ and 12″ Humminbird running the whole time ( usually 3-5 hours of fishing) 2-3 times per week.
When I bought new batteries for the new boat I had this conversation with the battery guys and brother in law. Both said the same thing that I always wanted to top it off and never let it drain.
Am I slowly ruining my batteries or doing the right thing?
This thread has sure been enlightening to me thanks for all the help sounds like I’ll start putting the charger on the starting battery every trip.
I started putting so called smart charger on starter battery after every trip. Never had much issue before but I will say my 75 horse 4-stroke mercury (2009) is cold blooded. So I figured I needed every last bit of juice in the spring and fall.
If I remember right from another post you have a 25HP Pike? That engine has a max amp output of 15 Amps. Like Iowaboy was hinting to that’s not much. With EFI and ignition draws that leaves very little actually going back to the battery even with the engine running higher RPM’s. While idling and trolling there is likely very little or even zero battery charging happening. Similar to my old 25 trying to charge a battery with a HDS 12 hooked to it, long story short it never tops off the battery. It just doesn’t have the ability even making long runs on the river. Over size your battery so you have enough capacity for the day and, get used to hooking up the charger after every outing.
I take it I need an ohm meter to check for battery draw? I will need to get one I just use a little minnkota battery tester. I run a helix 5 and a Lowrance hook 4 then lights and bilge pump which I have not used. To the best of my ability the charger I got says rapid charging up to 3 amp max it is a new one not an old one. I have had no issues ever with charging my trolling motor battery. I do have a master shut off switch which shuts the locators off my understanding is the I pilot is on this circuit as well when I bought it they put the cutoff switch in because they said it would draw power because of the GPS. I have been known to forget the switch as well. Basically I was just surprised at how low it was it read 12.2 volts before charging just the charger shows it had 77% charge I just figured the motor has not had enough time to recharge and I usually run the trolling motor all day then a quick jaunt to the landing when done. Meaning I don’t run the motor to much
iowaboy1 probably hit on the problem with the battery being only marginally strong enough for the motor and other draws on it.
If you want to check for unwanted draw on the battery when everything is turned off, remove the connections from the + side of the battery and connect a multi meter between the post and the connections. You’ll be looking for milliamps of current. There are sensors or a clock on a radio that may draw a little current but it should barely register any draw.
Mine is set up to charge all onboard batteries for trolling motor and main starting battery…so they all get charged every time I go out. I agree that most of my fishing results in insufficient main motor operation to fully restore all the graphs and pumps pull out on any given day. Thats what I have the onboard charger for.
I run one battery for my starter, Helix 9, and Helix 7. After an outing I will throw a battery tender on it if I know I’m not going to be out again the next day or two. I almost always get the “flashing green” of the battery tender when it sits connected within a minute meaning the battery is above 80% charged. My fishing boat has a 115hp outboard on it.
I do also care a powerpack with just in-case.
I have been using onboard Minnkota chargers for 15 years. I plug it in the second boat gets back to dock or in garage even if only fishing for one hour. IT stays plugged in over the winter as well. My batteries avg 6 years and then I change them even if they are working. I check water levels spring and fall and add distilled water if needed. I know a guy that worked at Interstate and he is the one that recommended that I do this.
Mwal
My 50hp Merc will kill the starting battery if you troll alot. Happened to me twice. EFI draws more then the charging system puts out at idle. Local lakes are to small to run around wide open to charge you would be dizzy from driving in circles.
You must be logged in to reply to this topic.
