Trolling Motor Battery, Starter Battery and Electronics

[fisherman7]

So my mystery continues. After about 90 minutes of heavy trolling motor use (high winds/waves) my electronics crap out. They're hooked to the trolling motor batteries, which are new. I've been all over the electrical system at the batteries. Cleaned and tightened the terminals, etc. I checked the voltage on the batteries. One was 12.3, the other was 9!

 

The boat is a 17' Yamaha G3 with a 115 Yamaha. Charged is a Minn Kota.

 

So a few questions if you don't mind.

 

1. When I was reconnecting the terminals I heard a motor/pump or something start up for about 5 seconds and then shut off. Pulled the wire off again and reconnected. No noise. Left the wire off for about a minute, reconnected and heard the sound again, coming from near the front left side of the boat, when my internal fuel tank is. Could that be a transfer pump or fuel pump????

 

2. My electronics are connected to my trolling motor batteries, but I've heard everyone has them connected to their started battery. Is that what everyone does?

 

Any help would be appreciated.

 

 

[BassMan11]

Lots of info on this around the forum. Usually your trolling motor batteries are used just for the trolling motor only. Put your electronics on the starting battery. That way they will get charged by the big motor when you are running from spot to spot. Best case scenario would be 4 batteries. 2 for the trolling motor, 1 for your starting and 1 for your electronics. But obviously you need the adequate space for that. This is what I am running and it seems to be working well this season. Just remember to always charge your deep cycles right after your trip. It helps their longevity.

Hope this helps.

[DRIFTER_016]

Yup, TM is on YM batteries and everything else runs off the starting battery.

[Steve Piggott]

Most electronics shut down at 9 volts.So you won't damage the unit.

[John Bacon]

Yup, TM is on YM batteries and everything else runs off the starting battery.

 

What are YM batteries?

[DRIFTER_016]

 

What are YM batteries?

LOL the Y is beside the T on the keyboard.

[porkpie]

Run your electronics off of your starting. The trolling motor batteries should be just for the motor.

[Lape0019]

You've solv d your mystery. Now go connect your units to your cranking battery.

[NANUK]

What size/#thrust is your TM ? 12v or 24v ?

 

12 v motor usually draw 35-40 amps in full speed,

 

You need to run your electronics from a battery which doesn't drain out

[fisherman7]

Thanks everyone! I really do appreciate how helpful the people on this board are.

 

Guess I've got some work to do this weekend.

[Garnet]

Being a 2017 I'm guessing a marina wired your electronics into your trolling motor battery's.

 

If that's the case I would careful be with this dealer.

 

When you get them hooked to your main starting battery they will still shut down if you spend a great deal of time in ones spot running a bunch of stuff.

 

Immediately start your big motor if your finder shuts down and let run for a bit.

Edited August 9, 2017 by Garnet

[Sinker]

Being a 2017 I'm guessing a marina wired your electronics into your trolling motor battery's.

 

If that's the case I would careful be with this dealer.

 

When you get them hooked to your main starting battery they will still shut down if you spend a great deal of time in ones spot running a bunch of stuff.

 

Immediately start your big motor if your finder shuts down and let run for a bit.

IF the starting battery wont run the graph, its not going to start the main engine.

 

The whole set up sounds fishy to me. I can run all day long (8hrs), steady trolling at 1.5mhp, with my bowmount hooked up to 2 31 DC batteries. You either have a charging issue with your batteries, or a battery that is pooched. I would suspect you have two batteries hooked together to make 24v, and one battery isn't getting charged (or its pooched). I run a dedicated battery just for my graph. Its just a small gell cell battery about twice the size of one you would get with a portable unit. I can run my lowrance for 2 days straight off that little battery, and it keeps everything neat and tidy. (no long runs of wire to my graph, and no interference from the TM)

 

I wouldn't take it back to your dealer either, I don't think they know what they're doing.

 

S.

[Garnet]

Hummingbirds seem really sensitive to low volts. My lowrances not so bad.

 

It's not to much problem for finders alone . Add live well, radio bilge, and making short runs with big motor. If your shuts unit off start engine immedaitly.

Edited August 9, 2017 by Garnet

[Old Ironmaker]

Don't forget the in line fuses going to the starter battery. I have had my Humminbird shut down due to low volts but the 115 Mariner would just crank over.

 

If you still have an issue you may be looking at a short somewhere. We pulled a red wire from a buddies dash a few weeks ago because he was loosing his GPS screen and had to restart it every 1/2 hour or so, and all of a sudden it was brown not red, lucky guy. Never rule out a short, it could save having a fire down the road.

 

Like Sinker said you may have a bad, or both deep cell batteries are bad or a bad connection between the 2@12 volts wired as 24V. Bow mount batteries take a pounding that a rear starter battery won't see much abuse.

Edited August 9, 2017 by Old Ironmaker

[grimsbylander]

I can run two live well pumps, two Lowrance HDS units, structure scan and a Point 1 electronic compass all day and still start a 200hp V-6 outboard. Keep the trolling motor batteries restricted to the trolling motor and charge your entire system after each use.

[fisherman7]

Hi all, it's a 24v system. I will this weekend transfer over the electronics to the starter battery and go from there. I bought the boat used but I'm only the second owner.

[Garnet]

As stated it's a good idea to charge your cranking battery after each outing.

[Old Ironmaker]

I always give the cranking battery a charge the day and night before a trip. I should charge it as soon as I get home like you guys say. Then it's all good to go at a moment's notice. I strongly suggest you invest in a good battery booster, under 100 bucks, small enough now to fit in a glove box and great to carry in the car in winter. I have given folks a boost on the water and the ramp more than once since I got it. Boosted my truck and a neighbours in winter too.

[grimsbylander]

I always give the cranking battery a charge the day and night before a trip. I should charge it as soon as I get home like you guys say. Then it's all good to go at a moment's notice. I strongly suggest you invest in a good battery booster, under 100 bucks, small enough now to fit in a glove box and great to carry in the car in winter. I have given folks a boost on the water and the ramp more than once since I got it. Boosted my truck and a neighbours in winter too.

 

That's a good idea. In the boat I just carry booster cables because I've got three more batteries just in case the cranker goes for some reason.

[Garnet]

I have 4 bank charger 15/bank. Just ordinary bass day when I come home it's 3 hrs to top up main battery. That's mostly my style of fishing short runs and extended time on trolling motor.

[adam lancia]

I fished with a friend a while back who had an accessory switch on overnight which killed the starter battery AND we couldn't even jump it from any of the 3 TM batteries for some reason. He also runs his graphs off the starter battery and eventually those flickered out. His voltage meter was showing under ten volts for the starter and he would barely get a click from the solenoid when hooked up to one of the TM batteries. A booster pack would have been perfect.

[fisherman7]

Well I switched it over a few days ago and so far it's been great!

[Garnet]

Not having enough from the trolling motor battery is common.

 

Don't turn the key 20 times it won't get better.

 

Check your battery connection. Make sure they are clean and tight.

 

Try the key.

 

Move to your jumper cables. Try the key ounce. Make sure you have good connection try the key 1 time.

 

Now the hard part your main starting battery is just to dead. Leave cables attached and wait 30 minutes and 45 would be better. This allows your good trolling motor battery to charge main.

 

That's 30 minutes of no key turning you do and you start over. And you have limited opportunity's so do it right.

 

I bought my power pack from Costco think it was $100. I don't carry my pack with because your fish finder will tell you to start the main and I've used the above procedure for 30 years.