Battery charger question

[Grute Man]

Im trying to charge my boat batteries on 12V 12A setting (fast charge) and the charger keeps flashing the "Fully Charged" light then the needle bounces up and down then goes back up to about 11amps.  It does this every few minutes or so.  Does that mean its a bad battery?

I have another battery that when I put it on the charger, the needel doesn't even move.  It just sits at zero.  Im thinking thats a bad battery because its not accepting charge.

For now I put the first one I mentioned here on slow charge 12V 2A.  Anybody got an idea what's goin on here?
Grute (Don)

[Spinach]

Yeah, it sounds like 2 bad batteries to me. I always charge my batteries with a trickle charge (2amp) I've had the same 3 batteries for more than 7 years and no problems. I charge them after every use and they last forever.

Same thing with my smaller 7amp batteries, charge them every time with a slow charge.

[DaveO]

are you using a manual charger or one of them new smart chargers? Also as Spinich says deep cycle bat. are not meant to be charged fast,, 10 amps is the most you want to put through it ,,and thats relay pushing it

[Grute Man]

Well since I haven't heard of smart chargers, Im guessing its not that.  I have it on 2 ams now - the slow charge.  Im hoping to salvage at least one of these.  I have 3 on the boat but don't think I need that many.  Thats just how it came.  Last year, I had NO problems.  Now this year, its like a brick wall.  Im wondering if they were stored right over winter.  Also, I think they were hooked up wrong when put back in the boat.  We'll see how the charge works later today.

Grute (Don)

[Spinach]

I paid around $60 for a great Minn-kota charger a few years ago at Gander Mountain, it automatically shuts off when the battery is fully charged and keeps the battery charged while plugged in. Just plug in the battery and forget about it, never worry about overcharging or cooking your batteries again.

Smart Chargers are the only way to go.

[DaveO]

yea Pat I have the same charger in the ice house,,,I love it,,,

A smart charger is a computer generated charger and it will analyze your bat. before it puts a charge on it.

The big problem with that is if the bat. is TO low it wont charge it at all.Then you will have to use a manual charger on it to get the juices flowing..

One more thing if you have bat. covers on it make sure your water level is up.

Good Luck

[Grute Man]

How high is the water suppoesed to be and can it be just tap water?

I'll have to get a smart charger.

Grute

[Realtree]

I believe it is recommended that you use Distilled water in batteries...not sure if it is different from auto to deep cycle batteries on this.

[Grute Man]

OK 2 of 3 are for sure dead  :death2:  Had one on the slow charge over night and when I hooked it up to the motor to try it, there wasn't even a spark.  The other one of these 2 didn't even try to take a charge.

The 3rd battery had some charge but not much.  The motor tried to turn over but it wasn't even enough juice to really crank it.  When I went to take the wing nuts off the battery, they were getting hot from the little bit of cranking I did.  I know they were cool because they had not been sitting in the sun.

Well looks like 2 batteries and a smart charger are in my future.  I really don't need 3 batteries.   Also, Im going to wire them in parallel for ease of charging.  What size cable to I need for that?  Regular battery cable I would assume.

Grute (Don)

[DaveO]

I'm not suggesting a smart charger at all,,,,,if i did I'm sorry,,,,I just meant to say if the bat. is relay low some smart chargers wont charge them.

Yes Dist. water is best and it needs to be just over the top of the plates