OutdoorMissouri.com

BornBad,



"[i]Starting batteries and deep-cycle trolling-motor batteries are different animals. Cranking today's outboards typically means spinning pumps, powering a strong electronic ignition and still turning a starter motor fast enough for a quick start.



Starting batteries have a large number of relatively thin plates that expose a maximum amount of plate surface to the surrounding electrolytes so they can produce a lot of power for a few seconds. The resulting shallow discharge is quickly replenished by the engine's charging system.



Trolling motors pull battery power at a slower rate for an extended period of time. This results in a deeper discharge that is usually replenished by a charger at the end of a fishing day. Deep discharge/ recharge cycling is hard on battery plates, so trolling-motor batteries are made with thicker, more heavy-duty plates.



And then you have dual-purpose batteries. They have enough plate area to start an engine, and the plates are stout enough to handle limited deep cycling. They are a compromise, however, and can't start an engine quite as well as a single-purpose starting battery or survive as many deep cycles as a true deep-cycle battery. Dual-purpose batteries work well in small boats that have room for only a one-battery system and in larger boats with starting batteries that must power an accessory load between engine starts.



A deep-cycle battery with a marine cranking amp (MCA) rating that meets or exceeds engine requirements can be used as a starting battery, but a starting battery should never power a trolling motor because a few deep cycles can kill it.[/i]"



Just so you know. [img]http://www.outdoormissouri.com/ubb/images/graemlins/boozer.gif[/img]

Recharge your batteries as soon as you get off the water if at all possible. Not tomorrow, not next week, immediately if you can. This will really extend the life. Also, if you don't leave an onboard charger plugged in 24/7, charge your batteries about every 30 days. The warmer the day, the more efficient the charge will be.

Thanks fellas. It was a simple matter of batteries too dead to get picked up by the onboard charger. Disconnected them and charged them individually for a couple hours with the portable. Hooked em back up and made sure everything was running ok, then let the onboard charger do the rest.

Just in time too. Am heading down to Forsyth tomorrow evening for a couple days of Rogue twitching and swimmin minnow action.

BB...Bumps2 is right on about the on-board chargers. If you install one in your boat, at least three good things happen:
(1)you can leave your boat on charge when not in use and the charger will detect when it needs to work and when to shut itself off. Your batteries are always "hot" when your're ready to go. (2) no more lugging around a portable charger and having to open hatches to get to the batteries. Hook it up once, run the plug out through a bilge vent, and you're good to go. (3) they charge up deep cycle batteries much faster than a portable charger. If you have a 10 amp portable, that's ten amps shared by two batteries. When/if you get an on-board charger, each "bank" has its own individual charging rate, generally ten to 20 amps per battery. After getting my MinnKota, I kicked myself for days for not getting one years ago. A good one is not cheap. However, you can go across I-44 to the Bass Pro Shop return store next door to the main store and usually find one for half the catalog price. That's how I got mine. Get the biggest (highest charging rate) you can find. It's worth the extra money. Good luck...bad batteries are a bummer. Especially this time of year. If you have to replace yours, take a look at the big yellow Everstart batteries at Wal Mart...for the money they are hard to beat.
My boat is an 18 foot fiberglass hull with a 24 volt 65 lb thrust trolling motor, and I have yet to run a pair of Everstarts down in a day of fishing.

Not as long as the boat will start. I know a few guys that run their starting battery as the 3rd battery for their 36 volts and it doesn't seem to hurt them

I usually only get 2 season out of trolling motor batteries.

In a pinch, I have used the starting battery for a trolling battery. Is this gonna hurt anything?

Leaving them plugged in for long periods of non use will kill them also.

You should disconnect them. You should alos run a simple test. Charge them separatly and the check the voltage on each and make a note of it. Let them sit, without using them for a week or so if you can. Then check them again to see if one is dropping alot more than the other. This is the best way to pick up a weakening battery in a 24 volt system. If you have a weal one, it will drag the other one down a lot faster also. Right now is a good time because the cool weather put some stress on them.

The same thing's happened to my trolling motor batteries. If you have a 24 volt motor, can you leave the batteries connected in tandem to use the portable charger or should they be disconnected?

BB,

Sounds like maybe you oughta look into buying an onboard charger for your boat. I have a big, tin deep v and a jon boat and have onboard chargers on both. Keep them plugged in anytime I'm not on the water. I'm talkin 24/7. They have electronics that keep them from overcharging your batteries. You do need to check your batteries periodically and add water as necessary. Guest is the brand I've got but there are several brands out there. Heard good things about Dual Pro. Cabelas has both and think BPS does also.

Hellbender is right in that most onboard chargers won't pick up a battery unless there's a small amount of charge left in it. Had that happen to me at Stockton last summer. Had forgot and left the key switch on and battery was completely dead. Had to put a portable charger on it for awhile before the onboard started charging.

BB some chargers won't recharge if there is less than 2 volts in a battery. Mine is this way and I have a little 1 amp (dumb) charger that I put on for a while. My marine battery charger will then go ahead and charge it.
Just a thought.

I broke out the boat from hibernation this past weekend.

Trolling Batteries: both trolling batteries I bought brand new 2 years ago died and will not take a charge (water was added). Counting those two, I have had 5 trolling batteries die since 2000. WTF? I don't know much about marine stuff, this being my 1st boat, I would think that a trolling battery should make it more than a few months past it's warranty. Is this normal?

2 Cycle Outboard: I have read some of you implying that it is better to premix the gas and oil rather than trusting the oil and gas to mix in the engine. When I bought the boat, the dealer (now out of bidness) told me to mix for the 1st 50 hours of use then just keep oil in the oil reserve. I rarely use the B motor, but I'd like to make sure I keep it in working order for years to come. What say ye?