Reply
 
Thread Tools Search this Thread Display Modes
 
Old 12-30-2019, 04:49 PM   #1
Senior Member
 
Juliet 15's Avatar
 
City: Bellingham
Vessel Name: Knot Hours
Vessel Model: Hatteras 58 LRC
Join Date: Feb 2019
Posts: 289
Are My 8D's Dead?

I installed a new smart charger in Nov, then left the boat for 2 weeks with the charger breaker in the OFF position (inadvertently). When I came back my two 8D 12v batteries were dead.

I've been charging them since, but for a week now the charger has yet to go below 13 amps charge (stayed at its max 30 amps for the entire first day).

Am I correct in assuming the charger is trying in vain to charge "un-chargeable" batteries? IOW, is my never-ending charge rate indicative that the batteries are toast?

They were new 3 yrs ago.
Juliet 15 is online now   Reply With Quote
Old 12-30-2019, 05:00 PM   #2
Guru
 
BruceK's Avatar
 
City: Sydney
Vessel Name: Sojourn
Vessel Model: Integrity 386
Join Date: Oct 2011
Posts: 13,329
Did you leave them with loads connected? If not, and they could not survive 2 weeks of no charging with no loads, they were already toast.
Can you hydrometer test them, are they open cell with screw caps? If so, how was the electrolyte level? Did it need topping up?
Are they still serving loads while you charge them? Might those loads be about 13A, equaling the 13A going in?
I suggest hydrometer or load test them, with no charge and no load. Depending on the answers to questions above, they might well be toast. Or not.
__________________
BruceK
2005 Integrity 386 "Sojourn"
Sydney Australia
BruceK is offline   Reply With Quote
Old 12-30-2019, 05:16 PM   #3
Senior Member
 
Juliet 15's Avatar
 
City: Bellingham
Vessel Name: Knot Hours
Vessel Model: Hatteras 58 LRC
Join Date: Feb 2019
Posts: 289
Thanks; good points. I haven't checked the fluid levels yet. The only items on there are a hydronic heater (fans and recirc pumps), and a couple priming pumps. I first started thinking I'd killed them when the heater/fans would audibly slow by about 40% if I activated the priming pump (small Facet wobble pump). It seemed like the charger was actually powering things vice the battery.

That's when I looked at the charger and realized it was still charging. It stayed around 14 to 17 amps, eventually reaching 13 amps and stabilizing.

I'll check the electrolyte and make sure it's topped up to where it should be.
Juliet 15 is online now   Reply With Quote
Old 12-30-2019, 06:28 PM   #4
Valued Technical Contributor
 
DavidM's Avatar
 
City: Litchfield, Ct
Join Date: Aug 2012
Posts: 6,785
If your charger continues to put out 13 amps then that means that you likely have a sulfate buildup on the bottom due to letting them discharge fully. The sulfate buidup is causing the continuing charger current. So your batteries are probably toast.

So now is the time to replace those horribly heavy 8Ds with 4 golf cart batteries. They will fit in the same space and give you as much or more amp hour capacity.

David
DavidM is online now   Reply With Quote
Old 12-30-2019, 07:27 PM   #5
Guru
 
Pete Meisinger's Avatar
 
City: Oconto, WI
Vessel Name: Best Alternative
Vessel Model: 36 Albin Aft Cabin
Join Date: Oct 2012
Posts: 3,145
Methinks your batteries are toasted. The modern consensus seems to be to get rid of those heavy back breakers, I agree !

pete
Pete Meisinger is offline   Reply With Quote
Old 12-30-2019, 07:31 PM   #6
Guru
 
oscar's Avatar
 
City: Bethlehem, PA
Vessel Name: Lady Kay V
Vessel Model: 1978 Hatteras 53MY
Join Date: Oct 2015
Posts: 1,098
Check water level and SG of the electrolyte. If it's close try an equalization. Take the loads OFF when you're resuscitating batteries!

If toast buy a few 300Ah LiFe's.......
__________________
https://ladykay.blog/
oscar is offline   Reply With Quote
Old 12-30-2019, 07:40 PM   #7
Guru
 
BruceK's Avatar
 
City: Sydney
Vessel Name: Sojourn
Vessel Model: Integrity 386
Join Date: Oct 2011
Posts: 13,329
Juliet, separate the condition of the batts from the issue of what if anything replaces them. The anti 8D crowd is drifting the discussion.
Check the instructions whether your new charger has the capacity to bring back sick batts which are saveable, some do(or claim to). If it has an "equalize" function try it, top up first if indicated.
__________________
BruceK
2005 Integrity 386 "Sojourn"
Sydney Australia
BruceK is offline   Reply With Quote
Old 12-31-2019, 10:27 AM   #8
Senior Member
 
Juliet 15's Avatar
 
City: Bellingham
Vessel Name: Knot Hours
Vessel Model: Hatteras 58 LRC
Join Date: Feb 2019
Posts: 289
Thanks all, good input. I went out last night and checked. BruceK was correct, my heater pulls 13 amps. - I checked the spec gravity and all 6 cells were in the red. - The charger is a brand new ProNautics 30 amp smart charger with an equalization function, so I turned everything off and hit that. - I'll run up there today and see what, if anything, that did. - Unfortunately, the other battery on this system is also a 12v wet battery, so I'm not sure I can only replace 1 with an AGM, Lithium, or other battery. The charger can do any type, but I believe they all have to be the same type.- Lastly, these are under-floor batteries; there's no height room for a taller battery. My understanding is that Li-Ion batteries and AGMs are taller...
Juliet 15 is online now   Reply With Quote
Old 12-31-2019, 11:36 AM   #9
Guru
 
tiltrider1's Avatar
 
City: Seattle
Vessel Name: AZZURRA
Vessel Model: Ocean Alexander 54
Join Date: Aug 2017
Posts: 4,308
I am curious, are we taking about 2 8D’s as the house bank and there is a separate start battery?

I find two 8D’s to be a small house bank. I also find a 30 amp charger to be a very small house charger. While I’d admit my house bank is larger than average at 1400 amps, I find 800-1000 amp house banks the norm on boats of 50-60 feet. I also find Inverter/chargers that charge at 100 amps to be most common. My back up charger is 40 amps. This I find barely adequate to run house systems while at the dock. In my case my 40 amp charger runs at 60% just to keep up with house loads. That leaves a meager 15 amps left to charge a battery bank.

This may not be relevant to our OP’s situation or there might be a bigger issue here, like over worked and repeatedly deep discharged batteries that could be easily killed in 3 years.
tiltrider1 is online now   Reply With Quote
Old 12-31-2019, 11:47 AM   #10
Guru
 
Russell Clifton's Avatar
 
City: La Conner Wa.
Vessel Name: Sea Fever
Vessel Model: Defever 49 RPH
Join Date: Sep 2012
Posts: 877
I agree with Tiltrider1. That is a small house bank, less than 500 amps. We have 4 8D for a total of 960 amps with a inverter that has a 100 amp charger. This past week I let the system get down to 11.8 volts and it took many hours of bulk charging at 14.7 volts and 100 amps to get it back to a full charge.
Russell Clifton is offline   Reply With Quote
Old 12-31-2019, 04:10 PM   #11
Senior Member
 
Juliet 15's Avatar
 
City: Bellingham
Vessel Name: Knot Hours
Vessel Model: Hatteras 58 LRC
Join Date: Feb 2019
Posts: 289
So, great questions, of course. I was being brief cuz my real issue was whether I was seeing a dead and unrecoverable battery or not.


I have a Hat 58 LRC, with 2 battery systems - the original 32vdc, and a 2nd 12vdc.


The house has one separate 32vdc bank and another, separate 12vdc bank. The 8D's I'm talking about are NOT house bank batteries.


I have 2 15kw gensets. Each has its own 12vdc 8D battery. Those 2 batteries are charged by this new charger. However, for some reason, the bridge electronics and the hydronic heater are both run off the port genset 12vdc 8D start battery. The new ProNautics charger I installed charges both genset 8D start batteries.


So, while they're not house batteries, they are used for more than just starting gensets. Interestingly, the boat ALSO has a small (3rd) genset, a 4.4kw Entec. It's sole purpose in life is to (you guessed it) recharge the genset and the main engine batteries. Since it uses the same genset 8Ds to start, it has a crank handle that allows it to be manually started.


This things is set up for long trips and has a lot of redundancies.
Juliet 15 is online now   Reply With Quote
Old 12-31-2019, 04:14 PM   #12
Senior Member
 
Juliet 15's Avatar
 
City: Bellingham
Vessel Name: Knot Hours
Vessel Model: Hatteras 58 LRC
Join Date: Feb 2019
Posts: 289
For clarity:
I have one house bank of 32vdc batteries with a Heart 32v inverter/charger.
I have separate house bank of 12vdc batteries with a Magnum 12vdc inverter/charger.
I also have a 3rd, non-house bank of 8D batteries, used to start the 3 generators (2 x 15kw, 1 x 4kw). This third bank also incidentally runs the heater and the bridge electronics. It has its own ProNautics charger. One of these batteries appears to be no good - red specific gravity and can't hold a charge.
Juliet 15 is online now   Reply With Quote
Old 12-31-2019, 07:27 PM   #13
Guru
 
tiltrider1's Avatar
 
City: Seattle
Vessel Name: AZZURRA
Vessel Model: Ocean Alexander 54
Join Date: Aug 2017
Posts: 4,308
With the added information I am thinking bad batteries. 30 amp is certainly enough for two 8D start batteries that also run electronics. I’m curious, have you checked fluid level and when you did, had the fluid level dropped enough to expose the lead plates?
tiltrider1 is online now   Reply With Quote
Old 12-31-2019, 07:47 PM   #14
Guru
 
BruceK's Avatar
 
City: Sydney
Vessel Name: Sojourn
Vessel Model: Integrity 386
Join Date: Oct 2011
Posts: 13,329
Juliet,I`m not a fan of running anything off a genset start batt other than the genset. One function of genset(s) is backup, which I would not compromise. When I bought my boat someone was running a fridge off the genset start batt, I soon changed that.
You must have experienced a genset batt charge issue to add a charger serving just those 2 batts. Apart from other modest solar, I have small regulated solar panel serving just the genset batt. I figured it only got charged when the genset ran, which might not be often enough.
As your batts are taking and giving 13A, after initially drawing the max 30A, are you sure they are cactus? An inexpensive hydrometer will test them for specific gravity which tells you if you have sulfuric acid in solution, or sulfur attached to the plates and water lacking acid. If it`s the latter, some chargers may "equalize" it off the plates back into solution but if not, it`s new batts time.
I`m no electrician or mechanic.I think about things, sometimes don`t get it right, but a lot of it is just commonsense. My modest solar install is DIY but has stood the test of time.
__________________
BruceK
2005 Integrity 386 "Sojourn"
Sydney Australia
BruceK is offline   Reply With Quote
Old 12-31-2019, 09:04 PM   #15
Guru
 
OldDan1943's Avatar
 
City: Aventura FL
Vessel Name: Kinja
Vessel Model: American Tug 34 #116 2008
Join Date: Oct 2017
Posts: 10,595
It has been my observation, there is always a small draw off the house batteries.
If inverter is on, even in standby, you are drawing from the house batteries. Open the inverter breaker.
Then tack on the 12vt fridge. Empty it, open the fridge/freezer and tape the doors open.
Then, the bilge pumps. W/O a bilge pump counter, you will never know if your bilge pumps cycle when you are away from the boat.
Then the small 12vt compartment fans.
Finally, any lights you leave on, even the LEDs
You could do everything 'right' but there is shade on the solar panels ...
__________________
Two days out the hospital after a week in the hospital because of a significant heart attack.
OldDan1943 is offline   Reply With Quote
Old 01-01-2020, 09:17 AM   #16
Guru
 
ranger58sb's Avatar
 
City: Annapolis
Vessel Name: Ranger
Vessel Model: 58' Sedan Bridge
Join Date: Aug 2013
Posts: 7,088
Quote:
Originally Posted by Juliet 15 View Post
My understanding is that Li-Ion batteries and AGMs are taller...
Can't speak to LFPs, but that's not necessarily the case with AGMs. An 8D, or Group 31 or whatever AGM will conform colsely to BCIGroup sizes.


Quote:
Originally Posted by Juliet 15 View Post
The house has one separate 32vdc bank and another, separate 12vdc bank. The 8D's I'm talking about are NOT house bank batteries.

I have 2 15kw gensets. Each has its own 12vdc 8D battery. Those 2 batteries are charged by this new charger.

So, while they're not house batteries, they are used for more than just starting gensets. Interestingly, the boat ALSO has a small (3rd) genset, a 4.4kw Entec. It's sole purpose in life is to (you guessed it) recharge the genset and the main engine batteries. Since it uses the same genset 8Ds to start, it has a crank handle that allows it to be manually started.
It shouldn't take an 8D to start a 15 kW genset. I'd imagine a single Group 31 with decent CCAs/MCAs would start one... of if necessary, a pair would do it. If you look at CCA/MCA specs on both battery and genset engine, you can work that out. (I would guess a single Odyssey 31M-PC2150 AGMs would work, given they trot out higher cranking amps than many (most?) other brands of G31s.)

-Chris
__________________
Chesapeake Bay, USA
ranger58sb is offline   Reply With Quote
Old 01-01-2020, 11:01 AM   #17
Guru
 
Russell Clifton's Avatar
 
City: La Conner Wa.
Vessel Name: Sea Fever
Vessel Model: Defever 49 RPH
Join Date: Sep 2012
Posts: 877
When checking a bank of batteries with a hydrometer, is it best practice to disconnect the batteries from each other, or can they be left together? Thanks
Russell Clifton is offline   Reply With Quote
Old 01-01-2020, 02:43 PM   #18
Guru
 
Bob Cofer's Avatar
 
City: Bayview
Vessel Name: Puffin
Vessel Model: Willard Vega 30
Join Date: Aug 2013
Posts: 1,444
Quote:
Originally Posted by Russell Clifton View Post
When checking a bank of batteries with a hydrometer, is it best practice to disconnect the batteries from each other, or can they be left together? Thanks


They can be left connected.
__________________
What kind of boat is that?
Bob Cofer is offline   Reply With Quote
Old 01-02-2020, 04:06 PM   #19
Senior Member
 
City: Yelm, WA
Vessel Name: "Convergence"
Vessel Model: Camano Troll
Join Date: Nov 2017
Posts: 399
One way to be sure is to use a carbon pile style load tester. You can get a pretty cheap one from habor freight.
Not that its the only way to do it, but I typically charge each battery fully and test them separately Disconnect them if you want, and just put a charger on them. Battery should charge up over 12v a few minutes after disconnecting the charger. if it shows good voltage, put the tester on it. They artificially load the battery and you'll know by the readout on the tester whether its any good. Sometimes they just drop way down. You know the battery is toast. Sometimes they drop down to about 9-10 volts under load, which isn't great, but you can work with it.
Just a hint or two. if you haven't used the tester in a while, it will steam for a bit, which can be startling if you aren't expecting it. Also, don't leave them on for more than a few seconds.
__________________
Toni Froehling
Day Island Washington
1994 Bayliner 4788
"Satisfaction"
ctjstr is offline   Reply With Quote
Old 01-06-2020, 01:22 PM   #20
Veteran Member
 
City: Grace Harbor
Vessel Name: Seabiscuit
Vessel Model: Mainship 43 aft cabin
Join Date: Apr 2016
Posts: 32
It could also be that the charger is defective. Test on a known good battery. I had 8ds and replaced them with golf cart batteries. Not enough cranking amps for my liking. Replaced those with two sets of 2 group 31 wired parallel. 205 AH each set compared with 225 on each 8D. Losing 10% capacity not a big deal because I have a generator. The two batteries together are slightly smaller than 1 8D. Each is less than 1/2 the weight. I buy the lead acid ones for $100 each. That is important because batteries lose capacity with age, cycles, and temp. At 4 years they will have 40 to 60% of original capacity.. I routinely change them out at the 4 year mark.
Rthomas is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Trawler Port Captains
Port Captains are TF volunteers who can serve as local guides or assist with local arrangements and information. Search below to locate Port Captains near your destination. To learn more about this program read here: TF Port Captain Program





All times are GMT -5. The time now is 04:02 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012