Battery issues or something else?

[WABOBO]

For the last 4 weekends or so I've been struggling with a power issue. I'm kind of lost...

 

a few few weekends ago, we left the boat ignition turned on by accident and went upstairs for dinner for a few hours. We came back, took the key out and went back to the city. The following weekend we came out, turned on the bilge & blower, waited about 5 minutes, turned the key, heard a pop through the speakers, then the boat was dead. It had no power. I figured the previous weekend we had drained the battery, so I put a charge on the battery, and switched out the old Polk amp for an exile xm15.4.  The battery finished charging, then we were fine for the rest of the day.

 

The weekend after that, same problem. Turned the blower on, volt meter read 12.6 or 12.4, I turned the key, and the boat died. No power. I charged the battery, put it back in the boat, turned the ignition on. It read 13V, then I watched it drop every 30 seconds or so. 12.9, 30 seconds, 12.8 and so on.

 

this weekend I had the same issue. Turned the ignition on, and the volts quickly dropped from 12.9 to 12.3. The battery was flipping between 12.3 and 12.4. Went to start it, and it popped then died. Except this time, I pulled my phone out to get onto this forum, and a few minutes later the blower switched on. I took the faceplate off of the stereo, turned the blower off, and then turned he key. The boat started.

 

so do I have a bad battery, is my new amp draining all of the power, or is there something else? The battery is on its 3rd season...just over 2 years old.

Thanks in advance!

[MadMan]

Sounds like a bad battery to me.  Does your boat only have 1?

[WABOBO]

1 hour ago, MadMan said:

Sounds like a bad battery to me.  Does your boat only have 1?

Yes, only one battery. 

[Bozboat]

Low voltage gremlins? Take the battery to the auto parts store and have it tested. If battery is ok, then it gets more difficult.

[WABOBO]

17 minutes ago, Bozboat said:

Low voltage gremlins? Take the battery to the auto parts store and have it tested. If battery is ok, then it gets more difficult.

gotcha. Looks like that's my next step. Thanks!

[Bozboat]

11 minutes ago, WABOBO said:

gotcha. Looks like that's my next step. Thanks!

Hopefully the battery is the problem 

[WABOBO]

Still having problems. The battery is not the issue, unfortunately. I picked up a new group 27 battery, and am seeing the same battery drain.

When they boat is completely off, I do not believe there is any drain on the battery. But when I turn the key on (ignition only, motor is off), the volts drop very quickly as described above. In a minute I might see the volts on the dash drop from 12.7 to 12.4 or 12.5.

all of the auxiliary switches are off, and nothing is plugged in to the 12v outlets.

[Bozboat]

How do the  battery cables look? Clean? Tight connections? 

Connections at the starter?

how old is the starter?

[WABOBO]

1 hour ago, Bozboat said:

How do the  battery cables look? Clean? Tight connections? 

Connections at the starter?

how old is the starter?

Battery cables look good. Boat has 160 hrs and original starter looks fairly clean. Took the cables off at the starter last night and put them back on, didn't notice anything out of the ordinary.

[TimbrSS]

Disconnect your amp and see if you have the same results.

[WABOBO]

I disconnected the amp, but that didn't fix it.

When I launched the boat at the beginning of the year, I forgot to put both floor plugs in. I didn't think I got too much water in the boat, but I'm wondering if something got wet and is now causing issues. The starter is pretty close to where the water was. If the starter or alternator got wet, would this be causing issues? 

Edited July 17, 2016 by WABOBO