Battery Questions

[adrianna3]

Ok, I have two deep cycle marine batteries in my boat on a selector switch, like the usual setup in a boat. I left the switch on "both" and now both batteries are dead[xx(]. I think I might have a parasitic drain somewhere in the boat. I was told that one battery will suck the other one dry if one is bad. The batteries are being charged right now.
My questions are:
1) What is the voltage supposed to read on a fully charged Battery? I'm guessing 12volts, but how low 'til it's no good.
2) What is the specific gravity of the electrolyte supposed to read on a fully charged battery?
3) How can you check for a dead cell in the battery?

 

[CIVANO]

http://www.interstatebatteries.com/www/faqs/tech_talk/maintenance/testing.htm

Some info on specific gravity and dead cells.

 

[Island Fish Lifter]

Alot of people will put a trickle charger on the batts all winter long. This is a mistake as it will boil the battery dry. So,the first thing I check when someone says they have a batt problem is the electrolyte level.
The best way to check your batts is with a load tester. After you charge them, I would take them somewhere to get them tested as you probably dont have a load tester.
If you find you have a weak battery, I would highly recommend replacing both.
If youre in Campbell River, I can come over with my load tester.

Good luck, Dave.

Fill the dam tub!

 

[adrianna3]

Thanks for the help guys. I charged them both and then took them in to get tested. They're both toast. One is 9 years old, so I can't fault that one. The other one was only 14 months old and pro-rated under warranty. That's the FOURTH battery in 16 months under the warranty (MasterCraft Nautilus). Never again will I buy another Canadian Tire battery. Time to try an Interstate.

 

[CIVANO]

http://www.acehardwareoutlet.com/(gi2wvy55rssi4e554pm1ev45)/ProductDetails.aspx?SKU=998016725

I have used this battery charger/maintainer. It turns off when the battery is charged and simply maintains it. I have it on boat, car and tractor batteries for up to 7 months at a time without any damage. If the link doesn't work it is a Schumacher SE-1-12S

 

[Fish Assassin]

I like the Energizer at Walmart my self.

Even though my boat came with a Nautilus battery and I have not changed it yet as the battery was new. I can't wait to get it off my boat. I have have problems with Nautilus batteries in the past and don't trust them at all.

 

[profisher]

Always start with 2 new batteries and change them both out when one fails. Use the good one on its own somewhere else.

 

[danthewire]

Pro Fisher is right on that call, replace them as a pair. For what its worth I have used the Costco deep cycle batteries for years, and so far so good. "DEPENDS" on conditions and use.I'm a light user maybe 25 to 30 days a year. And I reycycle them after four years regardless, I am anal about no battery problems. Dan

 

[adrianna3]

I talked to Rod Tipton today and he told me some interesting facts about dual batteries:

-If one is bad and used on the "both" switch the bad one will kill the good one.
-The bad one won't let the good one take a charge. It will "suck up" the charge intended for the good one.

I'll get a second new one, but it won't be a Mastercraft.

 

[danthewire]

He is correct. Dan

 

[redliner]

From what I've been told you always draw from one battery or the other. Likewise charge one or the other. The only reason to have the selector switch on both is to draw enough for a last hope start. I'm guessing replacing both at the same time covers what damage you may have done to the good one?

 

[Island Fish Lifter]

Not exactly Redline. Your reading too much into it. The main reason to replace batteries as a set is like replacing front tires that are separated; when one fails, the other one is not too far behind. Also, mismatched batteries will "fight" each other. Youre right about keeping one batt out of the loop just incase you need it.
A good example is this: a typical prawn puller will suck the charge out of one battery on a typical pull, even with one engine running as the amps drawn is more than the engine will charge, however there are exeptions.

Fill the dam tub!

 

[Sushihunter]

One of the things I have usually done:

I will start my boat on Bat1 and run out to the fishing grounds - usually an hour to 2 hours of running time. When I get there, I switch over to Bat2 and use it for fishing for the day. If I ever run down Bat2 while fishing and can't start, I should have a fully charged Bat1 waiting to be switch in for starting.

I will then run home on Bat2 and the run should top off Bat 2's charge. Next trip out, I start on Bat2 and run to the fishing grounds where I switch over to Bat1.

So far, this has worked well for me.

On occasion I will throw the charger on at the dock just to make sure everything is topped up.

One other thing - Be ware of dealers who try to sell you deep cycle batteries for starting your motor. They are not designed for starting. They release their power more slowly and can damage your starter motor. Keep the deep-cycle batteries for House batteries where you will be running small loads for long periods of time - like fridge, lights, electronics etc. That's what they are designed for.



Jim's Fishing Charters
www.JimsFishing.com
http://ca.youtube.com/user/Sushihunter250

 

[TenMile]

I installed an Automatic Charge Relay after finding myself dead in the waters a few years back in Renfrew -- best $50 I've invested on the boat. Made by Blue Sea and is called an Add-A-Battery system.

It isolates the starter and house batteries when no charge is being applied. You no longer need the 1-2-Both switch in your system as the ACR will combine both batteries when it senses a charge (either from the alternator or shore charger). It also protects your electronics from the transient voltage when you initially start the engine.

In the event that your starter battery dies, you can manually combine the house and starter to get the boat running. It's an inexpensive mod that I'd recommend to anyone.

TenMile
<'((((><

 

[Sushihunter]

quote:Originally posted by TenMile

I installed an Automatic Charge Relay after finding myself dead in the waters a few years back in Renfrew -- best $50 I've invested on the boat. Made by Blue Sea and is called an Add-A-Battery system.

It isolates the starter and house batteries when no charge is being applied. You no longer need the 1-2-Both switch in your system as the ACR will combine both batteries when it senses a charge (either from the alternator or shore charger). It also protects your electronics from the transient voltage when you initially start the engine.

In the event that your starter battery dies, you can manually combine the house and starter to get the boat running. It's an inexpensive mod that I'd recommend to anyone.

TenMile
<'((((><

Years ago, I had a 1980 Chev 1/2 ton 4x4 with an electric winch. I had a second battery installed to run the winch, and it was installed with a similar combiner as you describe. One problem is that these things lower the charging voltage as it passes through and it then takes longer to charge the batteries.

The guy who did the installation suggested the addition of a relay that would parallel the two batteries if you killed the main starting battery. I had a momentary switch on the dash that I could press that would jump the two batteries and allow you to get started without even getting out of the drivers seat. Pretty sweet deal

BTW, these things don't charge both batteries at once - it directs the charge to the battery that needs the charge the most.

For those of you with lots of cash to throw into your boat, check this site out for the ultimate in marine alternators and charging systems: http://www.balmar.net/

Jim's Fishing Charters
www.JimsFishing.com
http://ca.youtube.com/user/Sushihunter250

 

[TenMile]

quote:Originally posted by Sushihunter


BTW, these things don't charge both batteries at once - it directs the charge to the battery that needs the charge the most.

Actually, the Blue Sea ACR does indeed charge both batteries when it combines them.

Really good overview on how they work here: http://bluesea.com/viewresource/1366

TenMile
<'((((><

 

[Sushihunter]

quote:Originally posted by TenMile

quote:Originally posted by Sushihunter


BTW, these things don't charge both batteries at once - it directs the charge to the battery that needs the charge the most.

Actually, the Blue Sea ACR does indeed charge both batteries when it combines them.

Really good overview on how they work here: http://bluesea.com/viewresource/1366

TenMile
<'((((><

TenMile: Thanks for the info - this is obviously a bit different from the unit that I had in my truck.

I quite like the quality of BlueSea products, I've owned a few over the years. Just not this one.

Jim's Fishing Charters
www.JimsFishing.com
http://ca.youtube.com/user/Sushihunter250