Battery loses power quick from listening to radio?

There is a positive and a negative coming from the house battery (Optima Blue Top D34M deep cycle) in the boat going to the amp. I’ve had the dealer check my alternator and it appears to be putting out 13-14 volts as it should. The issue I’m having is my battery lasts anywhere from 1.5 hours to 2.5 hours then its dead (that’s from a fully charged battery). I’ve never had issues in the past with at least two stereo amps, but with the one single amplifier I'm now using the battery does not hold a charge very long and I can’t figure out why. Any thoughts?

My dealer suggested hooking up a battery combiner or an isolator. I choose to hook up a combiner since installation is simple. Not quite sure this did the trick or not, but havn't been able to try it out a lot yet, seemed like the battery still lost charge in a little over an hour. My second battery is a typical lead/acid battery. I have a battery switch, but now with the combiner there is no use for it (unless of course the house battery dies). Typically the switch would be at battery #1 (blue top).

Any thoughts?

High Amp alternator will do the trick.Shoot me an e-mail if you are interested. These alternators put out over 100 amps at idle!!!

Even though its a high amp output alternator, wouldn't the current batteries I have only last a certain amount of time due their design/style?

a few questions:

how old is the battery? have you had it load tested?

what size wiring running to the amp? which amp are you running? and how loud are you listening to the system? do you run the engine, as in cruise around, before/after/during?...trying to figure out what you have and how you use it.

neil...you've fished that add around in so many posts. give it up or advertise already. that alternator doesn't look too marine but it's hard to tell from the pic.

The battery that the amp runs off is less than a year old. The lead acid other battery (the one for starting) is about a year old. The dealer was checking into the alternator, regulator, and batteries. All checked out o.k. so I'm guessing they load tested them?

The wiring to the amp is pretty darn big, guessing 4 gauge. The amp is a Zapco Reference 360. I listen at about 70-90% volume when it drains the batteries quickly. I cruise before shutting down and listening at higher volumes.

are you sure that the combiner is hooked up correctly? i would start by verifying that your battery is getting charged. using a multi-meter, check the charge of the battery before starting. check it again after you've started it and the rpm's on the engine are up a little bit from an idle (1200 or so), then again with the stereo on.

the alternator should be sending over 13 volts which you said the dealer checked. make sure that the battery is seeing this charge.

are you running a gel and a lead acid battery together? that's not ideal, they re-charge at different rates.

Dealer just finished going through the system again with someone more experienced in electrical. The recommendation was to connect a battery Isolator instead of a battery combiner (why I don't know, they esentially will be doing the same thing for me). A batter combiner charges the "house" battery first and once the house battery is charged it will start sending a charge to the second battery as well. They also said to install a 31 series battery. And also hook up a 1 Farad capacitor right before the amplifier, which I guess makes sense...

I just did a battery isolator with a second battery install. I have 2 Rockford Fosgate Amps at about 1000watts, 1 12" sub 6 6" speakers, light bar, fat sac pump, yada yada, I have no problems at all. Isolator took about 1.5 hours to hook everything up. I wanted to do a switch too but everyone said to do an isolator, iim glad I listened. Autozone for $29.99 plus some terminal connectors. Isoloator charges both batteries simultaneoulsy not waiting to charge one first. GO with the isolator.

i've never had a capacitor but i've read that alot of people don't recommend them in these applications. they still need to be re-charged by the same charging system so they don't really resolve anything.

i too have a couple of rockford's, a 12 inch JL sub, 6 6.5's....no cap and no problems. i've got 2 batteries with a stinger isolator.

good luck

I don't think I'll use a capacitor. Travis, I think the isolator is more complicated than that - a battery switch set to both will charge both batteries at the same time. Talked to a high end audio place here and they said about the only thing I can do is get a battery that will hold a charge longer. Problem is, it takes longer to charge that way.

The way a combiner works is it waits until the first battery is taking a charge and gets up to 13.3 volts (appx). It then puts the two batteries in parallel so they both charge together, not one at a time. So long as the charging continues and the voltage stays above about 12.9 the combiner will keep them in parallel. When the charging ceases, or if a heavy load drops the voltage, then the combiner will open up to protect the other battery from being discharged.

I have to invest in a more powerful alternator, I just put lights on and drained the •••••••• of my batteries. I am using a common ground between the batteries.

I would get a switch dude.... You can go to boaters world and get a perko that will allow you to switch between batteries while underway...I have two optima yellowtops and a perko...they work great.. I am running my 3 amps and tower lights off them and i have yet to have a problem, not to mention pumps and mls.. just try that first

salty87 these are marine grade alternators, Im not trying to sell these units to make myself rich. I just came across a company that was located out of Ft Worth that builds the best alternators out there. I was only trying to give people ideas on how to fix there problems.

Just in case you think Im Bull Sh*tting you read about the company for yourself
http://www.penntexusa.com/

Untill you get your facts straight keep your opinions to your self

Thanks
The Management