Battery keeps dying

[Genevdb]

Up until about 2 months ago, I had one battery that started my electric start 15 HP Johnson motor, ran my 55 lb Minn-kota trolling motor and powered my very old Eagle depth finder. Also wired to front and rear lights on my 14 ft 1972 Mirrocraft aluminum boat. Ran this way for a couple or years, but have had issues with batteries lasting very long. Switched to a new starting battery to start the motor and bought a new Marine/RV battery for the trolling motor & depth finder about a month ago. I have a 5 amp charger that I use to charge the battery after each use. Went out today and the new battery wasn't holding a charge apparently after being on the charger for a couple days. Registers 9 Volts on my voltage meter. Could there be a short or something that is draining the battery? After replacing the battery several times in the last year, there must be something other than every battery I buy being bad. I am looking for suggestions, as wiring/electrical is not my strong suit. Thanks.

 

[Al U Minium]

As a general rule if the wiring looks good, it probably is good.

Dissimilar metals in contact with each other naturally corrode, add water (fresh or salt) with electricity and it gets worse not better.

You want clean connections mechanically tight.

Crimped or pressure connectors are superior electrical connections to soldered connections.

Adding a barrier coating may prevent corrosion for a time.

The battery should be in a battery box with a vented cover and secured in the boat.

Allowing a lead acid battery to endure hot cold environmental cycles will reduce the batteries life.

If you still have questions, could you post some pictures of your battery set up?

 

[airshot]

First I would get your battery tested, usually free at most places ...if reading only 9 volts, the battery is toast !! 12.6 and above is full charge, below 12 v is considered dead, below 11.6 v is considered a throw away.

 

[Genevdb]

As a general rule if the wiring looks good, it probably is good.

Dissimilar metals in contact with each other naturally corrode, add water (fresh or salt) with electricity and it gets worse not better.

You want clean connections mechanically tight.

Crimped or pressure connectors are superior electrical connections to soldered connections.

Adding a barrier coating may prevent corrosion for a time.

The battery should be in a battery box with a vented cover and secured in the boat.

Allowing a lead acid battery to endure hot cold environmental cycles will reduce the batteries life.

If you still have questions, could you post some pictures of your battery set up?

Thanks for your help.

 

[Genevdb]

First I would get your battery tested, usually free at most places ...if reading only 9 volts, the battery is toast !! 12.6 and above is full charge, below 12 v is considered dead, below 11.6 v is considered a throw away.

First I would get your battery tested, usually free at most places ...if reading only 9 volts, the battery is toast !! 12.6 and above is full charge, below 12 v is considered dead, below 11.6 v is considered a throw away.

Thanks. Tested my charger and it wasn't working, even though the lights were on. So I apparently have been just draining the battery. Got a new charger and will see how it works out.

 

[airshot]

Glad to hear you found it...but your battery will not survive, once they are killed, they wont come back. You mught get some charge into it, but it wont last... Get a decent digital vom and keep track of your batteries, you coukd have caught this earlier and saved some grief....many of us have learned this the hard way over the years....