Battery Question...C'mon hear me out!!!

[txarmydude]

Ok so I finally got my motor in; it starts right up and runs like a beast. It really ran well, seriously I was shocked that a boat this old would handle like that. Power steering was even added. Anyway, the boat started getting hard to start as the day progressed. It finally didn't even click when I turned the key over and I had to jump it with a portable battery jumper from the marina. That didn't even work right away; I had to leave it hooked up for a few minutes before it charged enough to start.

When I checked the battery voltage at the marina before jumping, it read 12V. That seemed a little low. We jumped it off and the boat ran perfectly, I just didn;t shut it off again until it hit the trailer. So I took it home and figured it was the battery. Well, I took the battery out expecting it to be dead as a doornail but guess what...14.6-15 Volts on the voltmeter in my garage!!! Ok, now I'm confused....

I bought this battery last summer when the boat wasn't running. I left it unhooked, inside the boat all winter and never serviced it. I didn't even fill it up with water until after my experience at the lake (didn't know I had to). So obviously I haven't treated the battery right. But the battery would read below 14 Volts if it was dead right???

Here's my setup:

1977 Cobalt 18' with a re-manufactured 260 MERC. Nothing crazy hooked up, just a JVC stereo and two speakers (Wal-Mart special) and a Garmin fish-finder.

Any ideas out there???

 

[Barnacle_Bill]

Re: Battery Question...C'mon hear me out!!!

Have the battery load tested.

 

[Fireman431]

Re: Battery Question...C'mon hear me out!!!

When using a jump box, you're supposed to leave it connected for 5 minutes to adequately charge the dead battery. It's transferring a charged state to the low battery, so it's not an instant fix. It worked just like it's supposed to.

Check the charging system on the boat. If the charging system is failing intermittantly, the engine will run, but it's using battery power to supply spark for the engine. You might have had a alternator not working properly after the boat sitting, and then started working again later in the day. Stranger things have happened.

As far as the voltage, Bhile is correct. Volts on a static battery don't mean a thing. A load test will determine the battery capacity to hold a charge under stress.

 

[singram]

Re: Battery Question...C'mon hear me out!!!

I just experienced the same thing in my boat. Just a word of caution. I took my batteries for a load test and, after a deep intense charge, they tested fine. When placed in the boat and used they would not hold up to the challenge of boat start-up and operation.

Had I taken the load test as gospel I would have found myself stranded in the middle of the bay.

I replaced the battery and enjoyed a day on the bay yesterday. No problems.

FYI. I did have my alternator tested and it was fine.

Must have been an old, badly sulfated battery.....

 

[Silvertip]

Re: Battery Question...C'mon hear me out!!!

You say you measured 14.6 - 15 volts on a 12 volt battery! That is not possible unless a charger happens to be hooked up to it at the time. A 12 volt battery provides 12.6 volts unless it is being charged. Next, understand that simply measuring battery voltage is not a valid test unlesss there is some sort of a load on it. Check it while cranking the engine and you will see what I mean.

 

[txarmydude]

Re: Battery Question...C'mon hear me out!!!

Thanks for y'alls responses! I will take the battery to autozone and have it tested. I assume there is some type of prorated warranty on this battery since it is less than a year old. Maybe I'll just replace it anyway...

 

[Rick.]

Re: Battery Question...C'mon hear me out!!!

12.6 should be the max. reading you get unless it is being charged as Silvertip pointed out. The only other thing is make certain it is as charged as you can get it before taking it to have a load test done. Best of luck. Rick.

 

[Fireman431]

Re: Battery Question...C'mon hear me out!!!

Thanks for y'alls responses! I will take the battery to autozone and have it tested. I assume there is some type of prorated warranty on this battery since it is less than a year old. Maybe I'll just replace it anyway...

Less than a year? Should be a 100% free replacement. Make sure it's a marine service battery and not an auto battery. An auto will start the boat just fine, but isn't made to take the beating that a marine battery gets.

 

[txarmydude]

Re: Battery Question...C'mon hear me out!!!

I took the battery in to have it load tested and guess what? Dead as a doornail... Wal-Mart gave me a brand new one for free. I went out to the garage to test it with my voltmeter and it tests at 17 Volts!

Apparently I don't know how to use my voltmeter.... LOL

 

[bassman284]

Re: Battery Question...C'mon hear me out!!!

Or else you need to throw that volt meter away and buy a new one.

 

[txarmydude]

Re: Battery Question...C'mon hear me out!!!

Or else you need to throw that volt meter away and buy a new one.

I had to go find the owner's manual for it online. It is a multimeter, and the 9V battery inside was going bad, so it works now. 12.6V on the new battery... Bonus - After actually reading the manual, I found out that I can test my switches that might be bad, too! I knew there was a reason I paid 60 bucks for the dern thing!!!