what battery is right for me?

[junior mills]

i have a 17' 2002 lund pro V, with a 2 stroke yamaha 90hp engine. I have 1 battery that just runs my trolling motor, and only my trolling motor. My other battery, runs the rest of the boat, (starts the engine, 2 livewells, gps/fish finder, interior lights, navigation lights, dash lights, bilge pump, and radio). The original battery that came with the boat lasted about 6-7 years. It finally died on me, so i bought a new one. I bought a avg sized no name brand marine starting battery. It would not stay charged for very long and kept dying on me. I assumed I bought a bad battery. I then replaced it with a Interstate starting marine battery. Same thing is happening to me again. I had it looked at and there is no short in the wiring, and everything is good with the system. Being that this battery runs the engine, and all of the accesorries on my boat, do you think that i need to use a deep cycle battery as my main battery in the boat? Does anyone think that this is my problem, if not i could use some advice.

 

[BobGinCO]

Re: what battery is right for me?

Is it possible that the motor is not fully recharging your starting battery?

 

[Don S]

Re: what battery is right for me?

If all you are buying is a starting battery and a 24 size battery, and you use the fish finder, keep the VHF on, and use your stereo a lot when the engine is not running, you might want to think about a size 27 or even a 29 combination battery if you have the room, instead of just a small starting battery.
Might be worth thinking about separate start and house batteries with a battery switch if you have the room, just so you don't find yourself with a dead starting battery when you go to start the engine.

 

[saumon]

Re: what battery is right for me?

If you get 6-7 years out of the old battery, the setup is fine. The battery isn't the problem.

There's 2 possibilities:

1) something is drawing current (as an example, I once had a NAV Light toggle switch that went bad with corrosion inside, so it stay to the ON position no matter what. There's no mast lights installed, the boat was parked in the backyard, but I noticed an evening, while it was dark, that the red LED of the switch was ON on the dashboard. It was enough to significantly weaken the battery over a couple of weeks period).

2) your engine isn't recharging your battery. On that boat, you should have a voltmeter. It should read around 14V while running (half throttle and up). If not, something's wrong with the charging system of your engine.

 

[UncleWillie]

Re: what battery is right for me?

With a voltmeter.

You should see 14.0+ volts with the engine running.
You should see 12.6+ for 10-20 minutes after the motor stops.
You should see 12.2+ a week later.

If it is below 12.0 volts after a few days, something is draining the battery in storage.

 

[Mule Laker]

Re: what battery is right for me?

With a voltmeter.

You should see 14.0+ volts with the engine running.
You should see 12.6+ for 10-20 minutes after the motor stops.
You should see 12.2+ a week later.

If it is below 12.0 volts after a few days, something is draining the battery in storage.

I'd say even if it's below 12.2. A 12 volt battery shouldn't be 12.0 even during storage.

 

[UncleWillie]

Re: what battery is right for me?

I'd say even if it's below 12.2. A 12 volt battery shouldn't be 12.0 even during storage.

I agree.
He is either going to see a voltage in the middle 12's or it is going to be in the 11's or 10's or worse.
Exactly where you draw the line is not too important.
It is either going to be good or bad.

Being a little bad is a lot like being a little pregnant! It either is or it isn't.

I just checked my batteries that have been in the garage since last Fall.
The big boat battery is at 12.52.
An old U1 Lawn Mower battery is at 12.42.