Battery question....is it safe?

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JAS
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Battery question....is it safe?

I am talking while this thing types so I apologize for any mistakes. It seems I'm running into one problem after another in preparation for this Catalina trip. We got to the boat this evening to discover the battery charger charging at 14.6 volts. This is highly unusual as it is usually at about 13.2 volts when I come on board after a few days absence. So I checked the batteries and none of them are hot but one of them is very depleted of water. Not all the way down to the plates but a lot more than the rest. So I added water what's the batteries continue to be charged that 14.6 volts continually. I have four Trojan 105 batteries and one 12 volt battery for the windlass. My question is I want to go to Catalina for two days is it safe or should I postpone until I get new batteries. The batteries have been on the boat since I bought it 4 years ago. We are supposed to leave for Catalina at around 7:30 a.m. tomorrow morning.

Joel Schwartz
s/v Get-A-Grip
1993 Catalina 36 Hull #1259
Newport Beach, California

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Sorry for bothering everyone about all this nickel-and- dime stuff but this is stuff that I'm learning about 4 the first time, and I can't seem to find the precis answers I am looking for on the internet.

Joel Schwartz
s/v Get-A-Grip
1993 Catalina 36 Hull #1259
Newport Beach, California

True Wind
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Jas
If you are reading your battery voltage on the analog meter that is standard fair from Catalina yachts, the accuracy may be plus or minus 10%. I would recommend a digital volt meter. It's how much current the charger is putting into the batteries that is important. Is there anyone that can test the actual state of the battery using a battery conductance and electrical system tester?

2003 Catalina 36

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Thanks TR...I'll break out the volt meter when we return.18

Joel Schwartz
s/v Get-A-Grip
1993 Catalina 36 Hull #1259
Newport Beach, California

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Thanks TR...I'll break out the volt meter when we return.18

Joel Schwartz
s/v Get-A-Grip
1993 Catalina 36 Hull #1259
Newport Beach, California

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A charger putting out 14.6 volts indicates the charger thinks the batteries are depleted.  A charger putting out 13.2 volts indicates indicates the charger thinks the batteries are fully charged.  A charger putting out 14.6 volts for an extended amount of time usually means something is amiss.  Without knowing your battery configuration, charger type, etc, hard to say.  Best guess is that you have four 6-volt batteries in two banks, parallel charging, and that one battery is kaput, drawing down the banks and causing the charger to never go into float.  The battery that was depleted of water would be my first suspect.

It's possible that the bad battery could draw down the other batteries, leaving you stranded.  If the battery is internally shorted, it could work your alternator too hard and lead to a failure here too.  Beyond scope to diagnose here.  If it were me, I'd remedy before leaving either by isolate and address, or by temporarily bypassing your entire Trojan setup and substituting in a 12v battery.

 

Nick Caballero
Retired C36/375IA Mk II Technical Editor

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Well, we are in Catalina...haha. Thank for your reply, Nick. I'm noticing my battaries deplete very quickly. Time for some new ones. I'm thinking duracell 6volt golf batteries. I hear good things about them, and they are a couple hundred dollars cheaper than t-105s for four.

Joel Schwartz
s/v Get-A-Grip
1993 Catalina 36 Hull #1259
Newport Beach, California

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Just checked my 4 Trojan t105s with a EZ-Red hydrometer (supposedly you don't have to compensate for temperature with this particular hydrometer). Trojan says 1277 = good battery, however my hydrometer says anything from 1250 and above = good battery (anyone care to explain the discrepancy on what is considered good battery health between hydrometer and trojan battery instructions?) .

Having never used a hydrometer before, here is my procedure: suck up and squeeze out electrolyte three times before taking a reading. I have 4 batteries, I only listed battery cells that read below 1275 (again Trojan says should be 1277, but I set a baseline of 1274 or lower just in case I'm a lititle off in my novice procedure):

Boat Batteries whole # = battery, and .1, .2, .3 equal cells within each battery:

Reading should = 1277 as per Trojan, should = 1250 or above as per Hydrometer.
Batteries/cells 1275 or above left out:

Bat 2.2 = 1266
Bat 2.3 = 1265

Bat 3.1 = 1257
Bat 3.2 =1274

Bat 4.1 1250
Bat 4.2 1245
Bat 4.3 1265

Any thoughts on what these readings mean by sailors familiar with testing batteries with a hydrometer?

Thanks a bunch--Joel S.

Joel Schwartz
s/v Get-A-Grip
1993 Catalina 36 Hull #1259
Newport Beach, California

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Joel
​I'm certainly no expert. What your specific gravity readings are telling you the state of charge. 1277 being full. What i  look for is for all cells to be equal. I don't like that one at 1245. Was that the battery that was low on water?

​I've found if a battery is truly shot the specific gravity in one or more cells  will be zip. No floating at all.
​Do you have a shore charger that is capable of "equalizing" you batteries. You should do that of regular intervals.
​Enjoy your trip.
Chuck

Chuck Lennox
97 MKii Ventura Ca
Island Girl Hull #1611

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I have a Promariner Protech i-series 4 stage charger, and it does mention anything about equalization. I will call manufacturer today to find out whether or not it can put out an equalization charge.

Joel Schwartz
s/v Get-A-Grip
1993 Catalina 36 Hull #1259
Newport Beach, California

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I have a Promariner Protech i-series 4 stage charger, and it does mention anything about equalization. I will call manufacturer today to find out whether or not it can put out an equalization charge.

Joel Schwartz
s/v Get-A-Grip
1993 Catalina 36 Hull #1259
Newport Beach, California

True Wind
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Jas

A good battery hydrometer will have a temperature compensation readout.  Did your's have that built into it?
 
State of ChargeSpecific Gravity
100%   1.265
75%     1.225
50%     1.190
25%     1.155
Discharged1.120

I would find someone with a good conductance tester. Most auto parts stores have them. I think West Marine strores do and they all do it for free.

 

2003 Catalina 36

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From Amazon: (I bought because it automatically temp. compensates)

Compact; easy-to-use; and easy-to-read -- automatic temperature-compensating, so there's no need to calculate anything.
Comes in plastic pouch.
Ranges are color-coded - Red = Low; Blue = Fair; Green = Good.
Graph shows electrolite specific gravity from 11.00 to 13.00.
MUCH easier to use and read than the "tube and float" types.

Joel Schwartz
s/v Get-A-Grip
1993 Catalina 36 Hull #1259
Newport Beach, California

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For high performance batteries that you feel have been on the charger long enough to reach fully charged, many of the readings indicate it might be time for new batteries.  While some of the difference readings between cells in the same battery suggest equalization might be worth a try, some of the absolute values indicate the state-of-charge to be less than 100%.

Specific gravity is only one of the tools at your disposal.  It's possible to have good acid, but eroded plates and thus a crappy battery.  It's possible for a battery to shed its lead to the bottom of the container, forming a conductive layer that gradually fills the allotted space in the sediment trap.  In time, this conductive layer may reach the plates, creating an elevated self-discharge condition.

In addition to acid condition via hydrometer, the other procedures at your disposal are open circuit voltage testing (plate condition), self discharge rate testing (conductive layer testing), and AH capacity testing (plate area).  All of these diagnostic tools when used properly give a full picture of your batteries.

You indicate that your charger never goes into float (assuming your charger is multi-stage) and this is a significant "overall" tool.  Trouble is, it cannot isolate which bank, battery, or cell is at fault.  All of the above procedures are in an effort to isolate which sub-component might be majority culprit, but fair to note that all of your batteries might simply be at end-of-life.

One last thing.  You should check to see if your charging system is what it should be.  It's possible that your charging system is never going into float because it cannot.  While your batteries seem to have seen better days, don't discount that an inadequate charging system has contributed.

Nick Caballero
Retired C36/375IA Mk II Technical Editor

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Can the tools required to carry out the additional tests you mention above be acquired at a reasonable price?

Joel Schwartz
s/v Get-A-Grip
1993 Catalina 36 Hull #1259
Newport Beach, California

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For open circuit voltage testing and self discharge rate testing, an inexpensive digital volt meter will suffice.  You might get lucky and the culprit battery will reveal itself in this way.

Unfortunately, the most useful test is really AH capacity and it also happens to be the most difficult.  For AH capacity testing, a calibrated load is put on the battery until a defined voltage is obtained and AH capacity is then calculated and compared to specifications. There are purposely designed AH capacity testers for 12v or 6v batteries, but I don't know the price.

DIY AH testing is really getting into the realms of science experiment and you're working with components and equipment that can get you into trouble.  I've done this using an inverter and a heater as a dummy load and while I'm personally comfortable doing the science, I'm not comfortable giving advice beyond this point.

Being in Southern California, there should be battery shops that are equipped to handle this for you.  If you are bent on DYI, surfing the internet will yield lots of ways to skin this cat.

Nick Caballero
Retired C36/375IA Mk II Technical Editor

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Joel
​I see 3 choices'

1.Pull batteries and take them to a battery shop that can do a load test on 6 volt batteries.

2. Buy a load tester that will load test your batteries on your boat.
https://www.zoro.com/otc-battery-load-tester-digital-131a-3182/i/G201615.... this is about 60 bucks.

3. Replace ALL the batteries.
​Based on your posted specific gravity readings and the age of your batteries I would be leaning toward replacement.
​ If you do replace your batteries, do your homework. There are many different brands and AMP hr rating.

You first decision is how much power do you need.

Chuck Lennox
97 MKii Ventura Ca
Island Girl Hull #1611

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Yup.  Chuck is spot on.  Fair to note that those kind of battery testers are really designed to put a starter load on a battery and are typically designed to gauge if a battery can sustain that for 10 seconds.  While you can't really determine AH capacity of a deep cycle battery using starter load testers, a weak deep cycle battery might reveal itself using this kind of test, especially when compared to other batteries in your bank.

Nick Caballero
Retired C36/375IA Mk II Technical Editor

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Nick is spot on about testing. You really need to do the 10hr current draw test for house batteries. MaineSail describes the process at marinehowto.com.  

Les

Les & Trish Troyer
Mahalo 
Everett, WA
1983 C-36 Hull #0094
C-36 MK 1 Technical Editor. 

Commodore

 

True Wind
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JAS

Just take those batteries out and take them to a professional. 

2003 Catalina 36

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