Electrical Issue - Boat Accessories Dont Turn On and Required a jump start

[Cmoneys06LSV]

Hi There,
I have a 2006 Moomba and it's my second year owning a wakeboard boat. My son was out and the boat died. I found the alternator belt had broken so I replaced it and charged the battery and it started and ran great. I anchored and hung out at the sandbar and it had no power when I tried cranking her.

I jumped it ran for 45 mins and then when I shut it off for dinner it wouldnt start. This time after i jumped it none of the accessories worked and again it wouldnt start after shutting it down. Battery is a few yrs old and tested good.

Any ideas where to start next would be a huge help. I'm thinking alternator but weird that it ran and battery was fully charged but nothing was working.

Thanks I'm advance!

CC

[secondsupra2004]

You can have a broken/shorted cell in the battery and it won't hold a charge for long. If the battery is over 4 years old, I would replace it and check the charging system after the new battery is installed.

[Cmoneys06LSV]

Thanks maybe I will try that if there are no other suggestions. I need to get back on the lake asap lol.

[MLA]

What was the fully charged at rest battery voltage? What or who said it tested good?

Great time to think about a dual bank setup.

[Cmoneys06LSV]

Well Oreilly said it's a good battery but did a quick test not a full test and said it's fine so maybe I should get a second opinion before I pull the alternator. I also plan to do a dual bank setup but need it back to normal first. Debating on next steps today as I look at it sitting on the side of the house lol.

[MLA]

A basic volt/ohm meter will test both battery and alternator, right where they are.

[secondsupra2004]

A basic voltmeter will only check voltage. It cannot load test the battery. Hopefully when you took it to O'reilly, they load tested it. I personally don't want to be miles from the nearest marina with a dead battery, so I check mine every season.

[MLA]

If a battery will reach full charge and hold, ill bet money its good. If a battery can not reach and hold a full charge, load testing it is like checking air pressure on a blown tire.

[secondsupra2004]

If a battery will reach full charge and hold, ill bet money its good. If a battery can not reach and hold a full charge, load testing it is like checking air pressure on a blown tire.

Sorry for ruffling your feathers. Meant no disrespect, just stating a fact that a basic meter won’t load test. I’ve seen multiple batteries in our shop showing a full charge and failed load test using our VAT40.
(That’s a testing instrument that measures volts, amps and load)
I have to say, I’ve never checked air pressure in flat tire though.

[MLA]

Sorry for ruffling your feathers. Meant no disrespect, just stating a fact that a basic meter won’t load test. I’ve seen multiple batteries in our shop showing a full charge and failed load test using our VAT40.
(That’s a testing instrument that measures volts, amps and load)
I have to say, I’ve never checked air pressure in flat tire though.

No feathers ruffled, just 32 years of testing batteries and diagnosing mobile 12V.

Yes, im very familiar with the machine. GM issued conductance testers when they first came out, like 98 or 99. I think it was a Midtronics maybe? After using it, i never used a "toaster tester" again. They can test a battery even if its not fuller charged. You cant do that with a traditional load tester. If you do, it will likely lead to a false failure, as an under charged battery is not expected to pass a load test.

Point is, not many DIYers have expensive shop grade equipment. But a $20 dollar meter from Harbor Freight will go a long way, before having to pull batteries and haul them to a store for testing. Same with an alternator.