Thread: Wire size

I just purchased a 112 terrova auto pilot will be running new wire minkota says 8awg wire and 60 amp breaker .my question is do I need marine grade wire? Or does it matter as long as it 8awg. Also I have heard /read where you need to stay with the same series size on the Batterys but I have a 27 and a 31 optma that was what was in the boat when I purchased it. So what size do I need to put with them . Long line quiet a bit .pull cranks a little.

Issues with batteries is the biggest problem with trolling motors. From mixing and matching different sizes, improper wiring, wrong fuses, and even different battery types.

I would pull new wire (as suggested) and go with the largest gauge you can get. Remember to utilize that same gauge wire for your crossover leads to link each battery, and your lead coming from the breaker to your first battery. I've had good luck with the Minn Kota 60amp breaker and utilize it on three different boats.

Next, when purchasing batteries, ensure they are the SAME. You can go with lead acid, AGM, or GEL. Just make sure they are all the same. I have no experience with GEL so I cannot help you there. AGM seems to have a better shelf life with very little discharge and will allow for continuous charging. You seem to get more life out of the batteries than a standard lead acid battery. For me, I utilize group size 31. We troll 8 to 10 hour days using nothing but the trolling motor in my 18foot Deep V walleye boat (and that is a 24v system).

Get the MOST cold cranking AMPS you can find BUT, keep in mind that it might be more important to ensure the AMP HOURS and reserve capacity is the highest you can get. I've done a ton of comparing over the years and contrary to popular belief, Optima AGM does not have the highest overall numbers when comparing batteries. I have owned and have had decent success with the Cabelas brand AGM batteries HOWEVER, the BEST ones that I have found are the Duracell AGM batteries. They seem to have the highest cold cranking amps, reserve capacity, and amp hours. The best prices I have found on them are at SAM's club.

When purchasing batteries, I've gone as far as to look at the manufacturing date to ensure they are all THE SAME. This has burned me in the past. Currently, I have three batteries in one of my boats (starting battery and two TM batteries). One of the TM batteries was produced at a different time (the sticker on the top is different than the others). This battery appears to have been built BEFORE the others. My last two trips out, I was only getting 4 hours of use. After doing a test, wouldn't you know it, the one battery is only taking a slight charge. As a result, I will be replacing BOTH batteries. These were NOT Duracells like I have in my other boat, but they will be.