Batteries?

[Rob_boater]

I have a 300.  I have 2 separate starting batteries for my engines (Good thing).  I have 2 Group 27 house batteries.  One is 2.5 years old and the other 1.5 years old (Added last spring).  The batteries have held the power for 15-20 hours no problem running 2 refrigerators, stereo, lights and water pump here and there.

This past Saturday we were out for ~6 hours and the stereo went dead meaning the house batteries went dead.  Started the motors and power was restored - Had a real hard time getting the windlass to pull the anchor since the power in the house batteries was low.  I thought well maybe I did not have the battery charger on all week.  When we got back I made sure the charger was on and working.

On Sunday we went out again and the same thing happened after ~5 hours.  The windlass really struggled this time.  I would think I should get more than 2 years out of these batteries.  Any ideas?  Another reason I want a generator installed but that is a whole other story.

[jjlovett]

You should get more - I get close to that with a single group 24 house battery. (I stay away from my cranking battery except for starting and running) You have more boat so maybe takes more juice?

I'm looking to upgrade to 2 grp 27s for the house system for next year - that should keep us good for a bit longer.

[ParkRode360]

I'm thinking that once you ran the house batteries down below their threshold (10%) with the windlass, they won't come back.  Someone (Dream Inn?) had posted something to that effect, and they won't come back 100%

[Rob_boater]

Great - This boat is killing me this year with repairs.


New complete canvas - $$$$$$$$$
Shower pump
AC Sump pump
LED Anchor light (Broke this weekend)
Hull compounding/waxing


Fall/winter work
Replace both blower motors (Very loud now)
Bellows/drive oil change pressure test
Spark plugs
Belts
Now 4 new batteries for next season
Water leak on the fresh water system somewhere

[osead]

BOAT=
======
Break
Out
Another
Thousand

[jjlovett]

Yeah - it's been a rough year for us too. I thought that we were hit hard when we put in the Floscan (an expensive install but so far definitely worth it) and have since had a battery 'explode' in the engine space, replaced the fuel pressure regulator and now a MAP sensor.

My friends always ask how I could get the money to buy a boat - I have to explain to them that it's not always so expensive to buy but the maintenance can kill you... 

[Herm]

Just your fridges will trash one battery in less then a day.  ANd if your getting into them for drinks and things like that it will be even faster.   And a stereo can use 20 to 30 amps an hour depending on the volume you run.  ANd those batts you have are good for maybe 100 amps if in good condition so it only takes a few hours to deplete one group 27 battery.  It sounds like your batts are probly in good shape but for what your doing you need more batteries.

[frodo13056]

It's true that if you drain a battery down below a certain level, they will not recharge back to the orginal point.  Actually, that's just the nature of lead / acid batteries. Lots of people go with AGM or Gel type batteries because they will last much longer even if you abuse (run them to the point of almost no charge left) them.
 What's just as important as maintaining your batteries in the summer is how you store them in the winter. Improper winter storage will also greatly impact their ability to last. I always pull mine and trickle charge once a month in the winter.

[Black_Diamond]

I would always replace banks of batteries at one time, if you replace one and not the other, you never know which is a problem and a bad battery can ruin a good one.

A good trickle charger can keep a battery fresh and in good shape over the winter.  The Battery Tender brand is excellent and inexpensive.

Repairs are always an issue, and worse if you are not banking a bit to cover the big unknowns..I spent $6k on new canvas, then had a coupler go bad..another $2k unplanned.  It's the way it goes I guess!

[jjlovett]

B_D - that's kind of what I was saying... We had planned on the Floscan upgrade and then... Well... That's boating.

[Rob_boater]

Just your fridges will trash one battery in less then a day.  ANd if your getting into them for drinks and things like that it will be even faster.   And a stereo can use 20 to 30 amps an hour depending on the volume you run.  ANd those batts you have are good for maybe 100 amps if in good condition so it only takes a few hours to deplete one group 27 battery.  It sounds like your batts are probly in good shape but for what your doing you need more batteries.

The batteries were holding fine all summer for a full day/night.  Now I can not get 5 hours out of them.  I am doing the same exact things I have done all summer.  It's is almost like this weekend they went bad all of a sudden.  I hope I can get by the rest of the season on them and no more overnights now.  I really wish I had a generator to periodically charge the batteries when on the hook. 

[alswagg]

Did you check the fluid in the battery's?  If the electrolyte is low, reserve capacity will be diminished.  I have had good luck with toping off with fresh electrolyte, could add another season to an old battery.  Al

[Rob_boater]

Yes.  I was hoping that was the case.  They are full.

[ParkRode360]

Don't smack me if i'm stating the obvious, but you've checked for corrosion at the terminals, etc? Just a thought...

[Vuja De]

Take the 12V house batteries out this winter and replace them with 6V battery's wired together.
Then post on how good they work so we can all make the change or not.   

If you don't want to go that route, try some deep cycle AGM batteries.  Worked great for me so far.  1st year though.

Dumb question maybe, are you at a slip with power and able to charge you batteries while away?
Or is the only charge they get coming from running the engines?