How well do these work when used for a short period of time? For example, while going WOT for a half mile or a mile. Will that throw a significant charge into my battery?

I had my graphs drain my starting battery a few times last season if I would leave them on for longer than 8 hours or so. I'd have to jump it from my trolling motor batteries sometimes just to get the motor started. I was thinking about adding an alternator charger or replacing the battery, or both.

What do you think? Is it normal for two graphs to drain a starting battery like that? The battery is an Everstart 24MS-6 that came with the boat, which I've had since 2009.

Thanks, Joe

http://store.minnkotamotors.com/category/392877/on-board_dc_alternator_char

I used to have two group 29 batteries on my Tracker Deep V for starting and equipment use. I would go larger on the battery but my deep V did charge the batteries from the motor as well. So and alternator charger did work for me.

Tight Lines

Pa Angler

That old 24 series is the problem. It doesnt have a great deal of reserve AH. Get yourself a good dual purpose battery and go up to a 27. I highly recommend the Autozone Duralast Marine battery. Mine went 5 years and never had a problem fishing 8 hours running 2 graphs and pumps .

They now have a 29 series thats only $10 more , never can have to much if you can fit it the boat.

As far as the charger question. What motor do you have ? That determines it amp output. The Minnkota is limited to 10 amps  but others like the TrollBridge can go higher if the gas motor has a large enough "alternator" or stator.  One 1 mile run will not do much no matter what you have. But a 20 mile day will make a difference specially with the TrollBridge and a outboard with 35+amp output. 

That old 24 series is the problem. It doesnt have a great deal of reserve AH. Get yourself a good dual purpose battery and go up to a 27. I highly recommend the Autozone Duralast Marine battery. Mine went 5 years and never had a problem fishing 8 hours running 2 graphs and pumps .

They now have a 29 series thats only $10 more , never can have to much if you can fit it the boat.

As far as the charger question. What motor do you have ? That determines it amp output. The Minnkota is limited to 10 amps but others like the TrollBridge can go higher if the gas motor has a large enough "alternator" or stator. One 1 mile run will not do much no matter what you have. But a 20 mile day will make a difference specially with the TrollBridge and a outboard with 35+amp output.

I've heard those are good batteries, and less than $100.

The motor is a 2004 Johnson Bombardier 2 stroke 90 horse, which is on a 2004 Stratos 275 Pro XL. Most of my favorite lakes are too small to make runs of longer than a mile. A mile is even a stretch on some of them, unless I go around in circles. I tend to target small lakes with crap landings and no pressure.

From whay you said about the lake it appears you are only running  the big motor a very limited time (great for the gas budget) but if you are startign the boat 10 times and only running it 1/2 mile thats not helping charging that battery much. Then fishing for 8+ hours with all your electronics on is doing in that 24 series battery. I have never heard of any 24 series walmart battery being a "good one"  The 29 series MAX Marine are know for being good ones. Your problem is pretty easy to diagnose. Marginal battery, no run time for the big motor to replenish the battery and you are fishing to long.  One needs to be fixed. I'll look but bing a newer motor you should have a pretty good charging rate from the BRP 90 but it needs to run a bit during the day to charge that WM 24DP