Dead Battery

[CTnewbie]

Forgot to throw the switch and battery is dead. Outboard is a Yamaha 150 (TXRC). I have a NOCO jumper that I fully charged overnight. If I’m able to jump it how long will it take for the engine to charge the battery up, or will we get stuck on the lake? Plan now is to jump, run around and come back to dock. But any advice would be appreciated!

 

[dingbat]

Depends on the size of you charging system but I would be more concerned as to why it went dead.

Should be able to leave the switch on overnight w/o killing the battery.
How old is the battery?
Load tested at beginning of season?
Could be battery is just plain end of life.

Either way, going dead just shorted its life expectancy substantially

 

[CTnewbie]

Depends on the size of you charging system but I would be more concerned as to why it went dead.

Should be able to leave the switch on overnight w/o killing the battery.
How old is the battery?
Load tested at beginning of season?
Could be battery is just plain end of life.

Either way, going dead just shorted its life expectancy substantially

It sat for a couple of weeks….

 

[Chris1956]

Was it moored and you had lots of rain? The bilge pump ran the battery dead? If no obvious drain on power, something is amiss.

 

[dingbat]

It sat for a couple of weeks….

The absolute worst thing you can do is to let a dead battery sit for any length of time.

Pretty much a death sentence in the near future, if not now.

Put a charger on it to see if it will hold a charge. Certainly wouldn’t be cruising off into the sunset w/o confirming it’s health first

 

[Chris1956]

Yamaha owners manual says that motor has a 25A charging system. That charging rate is likely at high RPM, and the charging tapers off as the battery is charged, so 3 hours would in the ballpark to charge up from near dead.

However, a Dingbat says, the battery is likely on it's way out, now that it has been run dead. If it is more than 3 years old, that would be another nail in it's coffin.

The big question is why did it go dead? Was it a drain or did it just fail to hold a charge. Over a 2 week period, a .1 Amp discharge would drain it.

 

[CTnewbie]

Yamaha owners manual says that motor has a 25A charging system. That charging rate is likely at high RPM, and the charging tapers off as the battery is charged, so 3 hours would in the ballpark to charge up from near dead.

However, a Dingbat says, the battery is likely on it's way out, now that it has been run dead. If it is more than 3 years old, that would be another nail in it's coffin.

The big question is why did it go dead? Was it a drain or did it just fail to hold a charge. Over a 2 week period, a .1 Amp discharge would drain it.

Thank you. So I guess no boating today. And will try to track down a drain. The stereo wouldn’t turning on last time we went out, so will start there. Thank you!

 

[Chris1956]

Stereo systems often have a "always powered" connection to the battery for their "keep memory alive" for radio station presets. I would not expect this to have that large of a drain, but that could be part of it.

 

[robert graham]

A good idea is to remove the battery cables from the terminals when you’re going to leave the boat sitting for several days or weeks…

 

[jimmbo]

I hope your battery is a wet cell, those damn AGM Batteries can be a real PIA to gat a charge into them when dead

 

[909]

The absolute worst thing you can do is to let a dead battery sit for any length of time.

Pretty much a death sentence in the near future, if not now.

This.

You literally cause permanent physical damage when it drops below 12 volts.

Certain battery chemistries ( like lithium) can literally catch on fire and start a thermal runway and go boom when they dip too low.

Lead acid is relatively safe. Batteries aren't that expensive. You can never go wrong by installing a new one. Spend a little, ... one less thing to worry about ever again.

 

[airshot]

Once a battery is killed dead they will never come back 100%. Find your drain then replace your battery, or get a good set of oars....

 

[Beagleville]

If it had run down overnight and you caught it, that would be one thing. However, having it run down with a constant drain for TWO WEEKS is another thing entirely. Probably best to replace the battery, and then find the drain or disconnect when not using it.