Solution for fish finder draining cranking battery?

I've recently added another fish finder so now I've got an SI fish finder mounted at my console and a DI at the trolling motor. Generally I like to leave both running while I'm trolling, but the problem is that my SI is tied into my cranking battery at the fuse panel. Is there any "trick" to use so I don't drain my cranking battery and get stuck on the lake? Was out fishing all day not long ago and thought I wasn't going to get it started. The only option I can think of is to re-wire it to my trolling batteries (I'm running 2 in parallel) but I didn't know if maybe anyone had any tricks I didn't know. I'm trying to avoid pulling any more from my trolling batteries, and I don't have room to add any more batteries. The other option I guess would be to start my big motor more, but I generally don't run it long enough to do much charging. Is there any way to rig up some sort of onboard charger or alternator to charge one battery off of another (or something like that)?

The fish finders do not pull much battery. If you fishing all day that happens sometimes. You can get a solar panel that will help a little. I just keep some jumper cables in the boat just in case.

a fresh battery will probably solve the issue .....i had similar issues when my old battery was tired ...didnt strand me but it did struggle

What battery do you have now, how old, do you charge it between trips, and what outboard?

Another solution might be to give the FF its own battery. You didn't say what FF you are using, but my HB Helix 5 DI GPS pulls about 650 mAH and I have a 7AH gel cell dedicated to it alone. I can run it for over 10 hours before depleting the battery. The batteries can be had for less than $30 and a good charger less than $20. My battery is about 8" long 4" wide and 6" high so it is easy to find a place to tuck it in any area. It doesn't spill so can be in a closed storage compartment and given the low current draw you can use fairly small wire to get the power to the console. At one point I considered mounting my battery under the console so I wouldn't have to run any wires at all other from it to the FF. I have wiring in place so it ended up in the Gas Tank/Starting Battery area just forward of the transom.

I have a dedicate battery for my electronics that gets charged every trip just like the other 4 in the boat. I won't leave the ramp without a set of jumper cables long enough to get from my trolling motor batteries to my crank battery.

Instead of jumper cables, I added a three way switch in the battery compartment that lets me add 1 of the trolling batteries to the cranking battery or switch to both trolling batteries to start the engine. Works every time so far with less hassle.

I think some of the above hit the nail on the head. First thing I would do is to see how old my battery is. If it is aged, I would upgrade to a new battery. Because it is your cranking battery, I would get the biggest you can get away with fitting in your location. For me, I use size 31 for everything.

I also agree with Catfan. When you charge your trolling motor batteries do you also charge your cranking battery? I recently got into a heated debate with a sales person at a boat place. I looked in the forward battery compartment and said: "you don't have any access or chase to get wires to the back cranking battery". He asked me why I needed it. I said: "so you can add a three bank charger and charge your cranking battery". He said... there is no reason for that, your motor charges your battery. My comment was, so, you leave the dock, you run 5 minutes, you fish all day long running your fish finder, radio, livewell aerator, and so on, you return to the dock (10 minute run) and your cranking battery is fully charged? He had the dumbest look on his face. Even made the comment that their service department doesn't install chargers on the cranking battery. Needless to say, I would never do business with that place!

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Originally Posted by davebrown42

Instead of jumper cables, I added a three way switch in the battery compartment that lets me add 1 of the trolling batteries to the cranking battery or switch to both trolling batteries to start the engine. Works every time so far with less hassle.

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I'm assuming you are running 2 batteries in parallel to your trolling motor? I seriously doubt throwing 24 volts to an outboard would make for a good day.

I use a deep cycle battery for starting and running everything but trolling motor . My trolling batteries only run that motor .

I would check the battery, my buddy runs 2 10" screens, 8" screen and a Humminbird 360 also the various livewell pumps all day off the cranking battery.

I was having the same problem as you and changed my battery system all around. My cranking battery is only for that. The deep cycle battery at the rear handled both sonar units and the trolling motor. This caused interference on the sonar units and drained the battery quickly. I put a whole new battery system up front for the trolling motor. This leaves the rear battery just for sonar units but still have outlet for trolling motor in case of an emergency. The two rear batteries are on a Pro Mar 2 bank charger and the front battery is on a single bank Pro Mar charger. The front box I built houses the deep cycle battery, charger, 60 amp breaker and a trolling motor outlet. This also adds some weight up front to balanced the load a little better. Always playing with something to try to make it work better. The old definition of a boat, " a hole in the water to pour money into"!!!

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Originally Posted by davebrown42

Instead of jumper cables, I added a three way switch in the battery compartment that lets me add 1 of the trolling batteries to the cranking battery or switch to both trolling batteries to start the engine. Works every time so far with less hassle.

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that is awesome....wish I could drive there and let you do that to my boat...then we could fish....dream on.Jk. I wish I had your know how.

Thanks for all of the great advice. I'll try to answer all the questions at once. I probably do need to check my battery age, but I do fully charge before going (onboard charger charges all batteries). I have a Tracker 175txw so I don't really have much space for any more batteries - I barely fit three into my existing battery compartment, and all my other storage stays pretty full. My fish finders are Humminbird 859ci HD DI and 899ci HD SI. I'll definitely have to get a set of jumper cables in the boat, and I'm gonna have to look into the switch idea as that seems like a good idea. Not sure why you would need the 3-way, though, as it seems that since I'm running two in parallel, if I just hooked the switch across both, it would be just as good and have the max draw. Any reason you need the option to use just one rather than both?

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Originally Posted by davebrown42

Instead of jumper cables, I added a three way switch in the battery compartment that lets me add 1 of the trolling batteries to the cranking battery or switch to both trolling batteries to start the engine. Works every time so far with less hassle.

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Also, what kind of switch did you use for this? Is there some other product that works fairly well as is, or did you have to build it from scratch?

"frog" .... I do hope you meant you put your batteries on the charger AS SOON AS YOU GOT BACK HOME from fishing, and not that you just charged them up the day/night before going !!

Leaving them in a state of discharge for any length of time, before charging them up, can lessen the life span of the battery. Also ... you should add distilled water AFTER the battery is fully charged, if the water level is low. And if the water level is below the tops of the lead plates, add only enough distilled water to cover the plates ... fully charge the battery ... then top off with distilled water. It's also not a good idea to top off all the way to the bottom of the fill holes !!

... cp :kewl

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Originally Posted by CrappiePappy

"frog" .... I do hope you meant you put your batteries on the charger AS SOON AS YOU GOT BACK HOME from fishing, and not that you just charged them up the day/night before going !!

Leaving them in a state of discharge for any length of time, before charging them up, can lessen the life span of the battery. Also ... you should add distilled water AFTER the battery is fully charged, if the water level is low. And if the water level is below the tops of the lead plates, add only enough distilled water to cover the plates ... fully charge the battery ... then top off with distilled water. It's also not a good idea to top off all the way to the bottom of the fill holes !!

... cp :kewl

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Wow, thanks Pappy. Actually I didn't know much of any of that (other than to use distilled water). Great info. I've never really spent much time researching battery maintenance...I just use them and replace them as needed. I guess I should give it a bit more thought. I guess I'm too busy trying to figure out all the new toys I "need"! :biggrin

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Originally Posted by knox_frog

Also, what kind of switch did you use for this? Is there some other product that works fairly well as is, or did you have to build it from scratch?

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You need to be careful with the switch idea. It will work and can be very handy, but there can be gotchas with doing it. The big one is with US2 trolling motors. There is also the possibility of electrolysis on metal parts that touch the water. Nothing insurmountable, just things that may not be obvious to somebody not familiar with boat wiring.

The three way switch generally lets you use either the cranking battery alone, a trolling battery alone or both in parallel.

Definitely start with the batteries. You may have two in parallel, but if one is bad or just a bad cell, the bad battery will almost immediately pull the other battery to it's state. When running two batteries in parallel, always be sure they are "like" batteries and close to same age. And (I know some will argue this), whenever you replace one, replace both to be sure!! As other's have said, you should be able to run all day (normal, non windy, TM not on high) with two batteries in parallel. Do as others have said, and one other thing, ensure your charger is actually charging to full!

I HAVE A BASS TRACKER ALSO,MY CRANKING BATTERY RUNS LIVEWELL PLUSE 3 DF,A 859,998 AND 1199 ALL DAY,SO FAR NO PROBLEM AND I FISH ALL DAY AND DO NOT CUT ANY OFF TILL I COME IN,ALSO RUNS BOUY WINDER AND MOTOR FOR RASING ONE DEPTH FINDER AND RAISING THE TM UP AND DOWN ON BOAT

Something I thought maybe I should mention here. Maybe everyone knows this or would disagree with me but I think this is good info. You can actually charge your deep cycle batteries too much. Depending on how much you use them on a daily trip they may not need recharged. They should be drawn down a good ways before recharging. If they are always topped off after only 10 or 20 percent usage it can actually harm them. That is why they are called deep cycle. Draw them down and bring them back up!!! Am I right on this??

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Originally Posted by Zinger

Something I thought maybe I should mention here. Maybe everyone knows this or would disagree with me but I think this is good info. You can actually charge your deep cycle batteries too much. Depending on how much you use them on a daily trip they may not need recharged. They should be drawn down a good ways before recharging. If they are always topped off after only 10 or 20 percent usage it can actually harm them. That is why they are called deep cycle. Draw them down and bring them back up!!! Am I right on this??

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Actually, no ... that's not correct. "Deep Cycle" means it can withstand greater depth of discharge levels. And anytime they fall below 80% charged, sulfation occurs on the plates and can cause loss of capacity and/or become impossible to recharge to a fully charged state.

(as per my interpretation of statements on this site : DEEP CYCLE BATTERY FREQUENTLY ASKED QUESTIONS )

... cp :kewl

I thought that was what I was saying. Guess I don't explain myself very well!!

Here is some more good info to go along with Pappy's Deep Cycle Battery FAQ
It is most important to recharge immediately after every use. This will prolong the batteries life. Never hook electronics to the trolling motor batteries. This will prolong your electronics life. I run 2 depth finders and aerator all day off the starting battery (group 31) and have never had it give out on me. Definitely have your starting battery load tested.

If your trolling why not just shut the console unit off?

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Originally Posted by barrelslime

If your trolling why not just shut the console unit off?

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My console has my side image that I like to be able to watch (TM is just DI) and using both also allows me to know the depth for both ends of the boat, front and back.

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Originally Posted by Clint

Another solution might be to give the FF its own battery. You didn't say what FF you are using, but my HB Helix 5 DI GPS pulls about 650 mAH and I have a 7AH gel cell dedicated to it alone. I can run it for over 10 hours before depleting the battery. The batteries can be had for less than $30 and a good charger less than $20. My battery is about 8" long 4" wide and 6" high so it is easy to find a place to tuck it in any area. It doesn't spill so can be in a closed storage compartment and given the low current draw you can use fairly small wire to get the power to the console. At one point I considered mounting my battery under the console so I wouldn't have to run any wires at all other from it to the FF. I have wiring in place so it ended up in the Gas Tank/Starting Battery area just forward of the transom.

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What brand and model battery are you running. My console FF is ok but my bown FF gets a lot of interference from my TM. Screen gets fuzzy when I use the TM. I've tried all kinds of things to eliminate it but cant.

NOCO Genius Boost Sport GB70 UltraSafe Lithium Jump Starter | West Marine

This is product that will help. Be very careful with jumper cables. I arc can be terror on your outboard and electronics. I agree with Catfan a switch can be good but can create excessive current to electronics. Proper size and quality batteries are the key. Battery maintenance and a good onboard charger is a must. I have a 4 bank Noco Genius that I plug in as soon as I get in. It stays plugged in till I head out again. I even tried to leave it plugged in as I headed to the lake once.:Doh:Thank goodness it came unplugged at connection with no damage.

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Originally Posted by Gabepeeps

What brand and model battery are you running. My console FF is ok but my bown FF gets a lot of interference from my TM. Screen gets fuzzy when I use the TM. I've tried all kinds of things to eliminate it but cant.

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Had that problem until i cleared out the stuff from one of my upfront storage spaces and put a battery in there just to run my front electronics. Wired the electronic cables with clips and inline fuse and hook it directly to that battery. I charge that battery every other trip out but it can be removed after every trip to charge if need be.

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Originally Posted by Barnacle Bill

Here is some more good info to go along with Pappy's Deep Cycle Battery FAQ
It is most important to recharge immediately after every use. This will prolong the batteries life. Never hook electronics to the trolling motor batteries. This will prolong your electronics life. I run 2 depth finders and aerator all day off the starting battery (group 31) and have never had it give out on me. Definitely have your starting battery load tested.

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Why is it a problem to use electronics on the TM battery and why will it affect the life of the electronics?

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Originally Posted by knox_frog

Why is it a problem to use electronics on the TM battery and why will it affect the life of the electronics?

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Every time you step on the TM's go button you create a surge on that circuit. Electronics don't like surges. Sometimes it lets the smoke out and they won't work anymore. You may get away with it for years but it only takes one time to blow some very expensive electronics. Some times you don't have any choice and have to use the TM battery. Also you are more subject to interference.

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Originally Posted by Barnacle Bill

Every time you step on the TM's go button you create a surge on that circuit. Electronics don't like surges. Sometimes it lets the smoke out and they won't work anymore. You may get away with it for years but it only takes one time to blow some very expensive electronics. Some times you don't have any choice and have to use the TM battery. Also you are more subject to interference.

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Thanks so much for the heads up. Guess I'm gonna have to get on pulling some more wire. Arrrgh.

Out of all the responses, not 1 mention of your alarms on fish finder.... If you go to settings page and set your voltage alarm it will tell you when it's time to start the big motor or turn stuff off.
You stated that you like to watch the down image so you should hear it. Also it's an option to put it on 1 of your watch box's on screen. Set it at maybe 10 volts ? Think mine are at 9.5 volts maybe.
Not at all saying your battery may not be in good shape cause 2 shouldn't run em down .

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Originally Posted by NIMROD

I use a deep cycle battery for starting and running everything but trolling motor . My trolling batteries only run that motor .

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This is how my boat is set up. I go one step further and disconnect the trolling motor when I put it on the trailer, and I have a cut off switch on my starting battery that I disconnect when I trailer the boat. My problem is that I would occasionally forget to turn off both fish finders. The cut off switch takes care of that for me.

Chaunc:

I am having that same problem and will follow that same path by installing a seperate battery dedicated to my thirsty Onix and HB 898 FFs.
Hope you good fishing this Winter my friend.

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Originally Posted by chaunc

Had that problem until i cleared out the stuff from one of my upfront storage spaces and put a battery in there just to run my front electronics. Wired the electronic cables with clips and inline fuse and hook it directly to that battery. I charge that battery every other trip out but it can be removed after every trip to charge if need be.

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