Boat wiring question

Any rigging people out there?

The boat I purchased a couple months ago was set up to have everything run off of the starter battery. It never had a Trolling motor or much for electronics in it and the front battery compartment never had battery’s in it. Everything on the console runs off of the starter battery. THIS MAKES ME NERVOUS when I am not using the main motor and I see the volts dropping on my Hummingbird.

So my question is: Should I rewire the console to one of the two batteries in the front and pretty much leave the Starter battery for starting? I know that there is a harness that runs out the side of the battery box and goes to the back of the boat but I can not tell where the wires run.

How is your power system set up?

Thanks

All electronics run to my starting battery. Trolling motor is only thing that runs off my deep cycle batteries in my rig.

More info needed.
What graphs are you running?
What size battery are you using?
Are you asking to run a separate battery where the trolling motor battery goes? Are you putting a trolling motor on the boat?

Front battery is hooked to troller 9″ depth finder and rear trolling motor if so needed, and one battery in back is for two depth finders in back (its a tiller) bilge pump livewell and navigattion lights and interior lights the other battery in back is just for starting. seems to work for me.

Yes I installed a 24v Minnkota powerdrive on the front.
Running a Hummingbird Helix 7.
Never thought to look at what size the starter battery is.

Noted that after about 2 hours the battery is down to somewhere around 11.4 Volts. Motor starts ok but Hummingbird doesn’t like it. Low Volt alert and sometimes have to restart hummingbird to get it to work.

thanks

A good starting battery and a helix 7 should be no problem.

I have the low voltage alarm set on my Humminbird per Mercury support suggestion for my motor. Suggest you do the same and all should be good. They responded in 2 hours to my question as to setting.

My 90 Yamaha will start at 11.4.
For now i will just start the motor once in a while and check the batter size and condition more closely.

Eyekatcher and ripjiggen, and everyone else thanks for the suggestions.

Run your graphs off starting battery. What your voltage says at your graphs is going to be lower that what your battery actually is. Running small wire to your graphs your going to have voltage drop.

Starting battery would probably power a helix 7 for a week….I run a helix 12 and 2 additional 9″ graphs plus livescope, all off my starting battery. Never killed it

Carry some jumper cables or jump pack for peace of mind but shouldn’t be an issue with a good battery.

snelson223 wrote:

Run your graphs off starting battery. What your voltage says at your graphs is going to be lower that what your battery actually is. Running small wire to your graphs your going to have voltage drop.

Didn’t think of that thanks

I run my electronics on a separate lightweight lithium battery. It is not tied to the boat system in any manner, so no worries about starter draw. Recharge after the end of the day. If the boat is tied to a dock with no electric, just unplug the battery and take it to the cabin to recharge, weighs less than 5lbs. Use the same battery in the winter for my ice fishing.

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Good to have a jumper on the boat and/or in the truck.Keep in mind that if you rely on tilt & trim loading and trailering your boat will be no fun in the ‘down’ position.

My advice is to get a bigger starting battery. I’m assuming you have a group 24 starting battery? For that 90 hp you could very easily go with a group 27 or 31 deep cycle and have way more than enough CCA for starting and plenty of capacity for everything else.

This is how I roll.

A reliable gas kicker motor is also a nice piece of mind to have .

Was this a used boat purchase? How old and what size is the starting battery? A helix 7 doesn’t draw much, but depending on the run length from the battery to graph, you may want to look at the guage of wire used to avoid voltage drop and getting the clearest image. Clean power supply is often the problem if guys aren’t getting good images, especially on 10″+ units that draw more.

The trolling motor should be the only thing rannoff the 24v battery system.

TheCrappieFisherman wrote:

Was this a used boat purchase? How old and what size is the starting battery? A helix 7 doesn’t draw much, but depending on the run length from the battery to graph, you may want to look at the guage of wire used to avoid voltage drop and getting the clearest image. Clean power supply is often the problem if guys aren’t getting good images, especially on 10″+ units that draw more.

The trolling motor should be the only thing rannoff the 24v battery system.

The Hummingbird is plugged into the main fuse board under the dash. But the entire wire length is in tact and original length.
The battery is a 2 year old 425cca.

Next time out I will take my volt meter with me and check the voltage at the battery and compare to the Hummingbird.

Thanks

isu22andy wrote:

A reliable gas kicker motor is also a nice piece of mind to have .

Ya maybe in a year or 2. But that is a consideration for the future

Yup small battery. An interstate 24 has 550 cca and a 27 has 600. So just by cold cranking amps I am willing to bet you have an undersized battery. Easy fix.

You should be fine, but you will want to jump up to a 27 group and a 31 group would be the best.

Heavy gauge marine wire 10-12g and you will never have a problem.

If it makes you feel better, I run 4 12″ graphs, livescope, power pole pump and all accessories of a group 31 AGM and I have no problems, and I leave everything on all day. you should be fine, but again, I would maybe just jump up a group or just go to a 31 and call it fine.