Battery replacement

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Fighterpilot

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Apr 17, 2011
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34 ft Californian I just acquired has two 8D batteries in an impossible place in the boat. Outboard of the port 3208N engine. They look pretty bad, neglected, and how old I don't know, nor did the POwho didn't use the boat much. One is said to be for start and the other house. One perko switch with 1, 2, both, and off positions. Don't live aboard nor spend more than a weekend at sea. Have a generator and will remove the ice maker and probably the refrig--just use ice chest so demand on house battery isn't great. Have*been told*that multiple 27s or 31s could be used.* I think I understand that wired in parallel you get max cranking amps and in the case of 6 volts wired in series gets 12 volts. Is that correct? For the 3208NAs would two 27s in parallel be sufficient. I'm in Florida so only have a few cold days in the winter and our use would be minimal during Jan. and Feb.* 70 degrees out there now. How about two 27 deep cycle for the house side?*Have seen*opinions that*the wet cell seem sufficient considering cost difference compared to gel etc. Also Advanced Auto got a plug for their batteries.
*
I considered moving the battery location but that would require a lot of new wiring and not sure where I would put them. Considered the 6 volt batteries but they are pretty heavy as well so would like to stay with 27s or if necessary 31s. Your thoughts on size of battery, type, and brand name. Thanks
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Fighterpilot wrote:**Is that correct? For the 3208NAs would two 27s in parallel be sufficient.*** *
*
Your thoughts on size of battery, type, and brand name. Thanks
*
*
*Correct, connecting 12 volt in parallel will give you 12 volt output.*

You need to check the total amperage of the batteries you are considering.* 27's and 31's seem a little on the small side for 3208 diesel's.* My Californian came with two 8D wet cell.* When it was time to replace them I went directly to the Interstate Battery Distributor and they recommended switching to*4D wet cell's.* Two by themselves,*provide plenty of power to run the household demands and start the engines.* They are narrower and only weigh around 100 lbs each.* Also saved enough room that by expanding the*battery box length a couple inches, I was able to have three 4 D's side-by-side, which is more total amperage than the 8-D's.** I get more than seven years service out of each battery and stagger their replacement.**

Larry B


-- Edited by Edelweiss on Tuesday 6th of December 2011 07:46:40 PM
 
The 4 Ds would work, but at 100lbs there is no way I can get them back into the boxes. Don't know how I am going to to get the 8Ds out. Wish I knew how they got in there to start with. May have to build a winch system to get them moved to the centerline so two people could lift them out. Two big thru hull strainers in front of the port engine complicate the situation. We are going to have to remove the port fuel tank and replace it so may just try to pull the batteries at that time, even though they may be still OK. With the deck cut open and the tank out might have enough room for two people to work. Thanks for the suggestions.
 
Depending on the make, a lead acid wet 8-D is going to weigh in between 125 - 140 lbs.* They're heavy and*difficult*to handle in tight spaces.* The 4D's are only about 100 lbs and narrower.* I dont think you want to go much smaller than these.*

I usually get my son and one of his friends to horse them around for me.* We use a 1x4x4 fir plank to slide the battery on*in the engine room.* For one person it would be a work out, but get a couple of young guys and it's a peace of cake.

LB
 
For a warm weather start on a 3208 setup a single Start #31 would be fine , but most folks choose a pair.

For the house the 6v golf carts work best as they are actual deep cycle batts.

Most 8D or 4D are starts , not useful for true deep cycle use.

One pair or two , depends on your requirements and space.

IF space floor is at a premium the L-16 style is taller and a pair should do.
 
It has also been suggested the West Marine 6 volt are good in a pair for the 12 volts. They aren't as large and heavy as a 4D but provide good capability. I think they weigh around 63 lbs. Wouldn't a pair of those also work for start? The old battery charger and the batteries would probably do better if all the batteries were the same, or isn't that a big consideration as long as the batteries are the same type, that is like the standard wet cell==although one pair may be deep cycle vs start type.
 
Fighterpilot wrote:
It has also been suggested the West Marine 6 volt are good in a pair for the 12 volts. They aren't as large and heavy as a 4D but provide good capability. I think they weigh around 63 lbs. Wouldn't a pair of those also work for start? The old battery charger and the batteries would probably do better if all the batteries were the same, or isn't that a big consideration as long as the batteries are the same type, that is like the standard wet cell==although one pair may be deep cycle vs start type.
*Ray

In the fishing industry we often used pairs of 6 volt batteries, gave a lot of amperage from a relatively small footprint.* But the problem we ran into, all to often, was if one*6v battery failed the other wouldn't start the engine.* And with a dead short in one battery and*you*ran the*engine on the shorted battery*would often take the diodes out in the alternator.* So we went back to standard 12V wet cells.* Most chargers will handle mixed sizes of batteries, just keep the types gells, agm, wet acid cells*all the same.

Sound like your boating use is a lot like mine, fishing and running to and from.**If you are just weekending it, like you say, and you have a gen set and are not afraid to run it, you should be good with wet cell batteries.* They will provide you with the best service for starting engines, down riggers and electronics.* You don't want to use deep cycle batteries for those purposes. You might be able to find some earlier posts on this site that contained*articles about battery use and types.*

Good luck

Larry B


-- Edited by Edelweiss on Wednesday 7th of December 2011 10:20:00 PM
 
I think they weigh around 63 lbs. Wouldn't a pair of those also work for start?

Yes and no.

Real Start batteries have a huge number of very thin plates , a huge lead internal surface area that holds the voltage up well during the few seconds it takes to start. That is reflected in as huge CCA cold crank amps rating.

True deep cycles , frequently a 6 V used in a pair or bank have very thick plates , at about the same weight.

The thick plates mean less surface area , so poorer results holding up huge amperage during a start sequence.*

But if the start is EZ , and there is a bunch of batts,, the surface area will usually be enough.

The deep cycles can be discharged (slowly) to hahd dead* (SOC 50%), and will recover hundreds or even thousands of times.

Starts DIE when deeply discharged even only a few times.

Different internals for very different use .

Buy what you need Starts to start (will have CCA rating) and golf carts or a deep cycle batt (will have "20 hour" rating) .

Most folks don't use a hammer to drive screws ,same with batteries.


-- Edited by FF on Thursday 8th of December 2011 04:51:53 AM
 
Edelweiss wrote:Fighterpilot wrote:
It has also been suggested the West Marine 6 volt are good in a pair for the 12 volts. They aren't as large and heavy as a 4D but provide good capability. I think they weigh around 63 lbs. Wouldn't a pair of those also work for start? The old battery charger and the batteries would probably do better if all the batteries were the same, or isn't that a big consideration as long as the batteries are the same type, that is like the standard wet cell==although one pair may be deep cycle vs start type.
*Ray

You might be able to find some earlier posts on this site that contained*articles about battery use and types.*

Good luck

Larry B



-- Edited by Edelweiss on Wednesday 7th of December 2011 10:20:00 PM

*Ray

From another series of posts, I*just recently reviewed this*article regarding battery selection,*use and maintenance.* This appears to by written from an RV perspective, but also applies to maine use as well.*

It will be an excellent reference for you.*It is pretty straight forward and gives a fair review of the different battery types and some "spot on" advice for battery care.* I*believe it will answer all your questions regarding battery selection and use. (Site*below)

http://www.phrannie.org/battery.html
 
I guess my configuration would sort out to two start batteries and two 6v for house--recognizing that if one house battery fails I am now at 6 volts. But since I am not living in it or spending more than a weekend at a time in it I guess I could jumper cable from a start battery if I needed to.
Now the question is 24, 27, or 31 for start. Looking at a 2008 West marine catalogue it is interesting to note they have a 24 series seavolt with 1000MCA which is more than their 27 or 31 series they offer. But it is also noted the 31 group is a deep cycle. I'll have to go on line and search 31 starting batteries and see what I can find, as well as a trip to Wally World, Sams, and Interstate. Thanks for the guidance.
 
Fighterpilot wrote:

I guess my configuration would sort out to two start batteries and two 6v for house--recognizing that if one house battery fails I am now at 6 volts.

I guess I could jumper cable from a start battery if I needed to.
Well .... sort of. If we look at that statement in combination with Larry B's mention of the fishermen's experience with 6 volt batteries prompts me to put on my instructor's hat for a moment.

All lead acid batteries are made up of 2 volt cells in series. A 12v battery is 6 x 2v cells in series , a 6v battery is made up of 3 x 2v cells in series. Wiring two 6v batteries in series to provide 12v is electrically no different than having a single 12v battery. The only difference is there are two cases instead of one.

A failure of a single cell in a 12v battery creates the same situation as the failure of a 6 volt battery. The bad cell can short out or go open (much less likely than a short) and the results are the same. Except - if you have two 6 volt batteries you can add the good*battery to your exisiting bank and lose only the capacity of*one bad battery.

For example. If you have two banks of two 6 volt batteries, each pair wired in series to provide two separate 12v banks and you lose one 6v battery, chances are that if it is a short you won't know about it until the cell is dry and your buss voltage on that bank*is too low to be useable. But, when you identify the bad battery you can isolate it.

This leaves you with one 6v battery. You can't just jumper it across the output of the other 12v bank or you will regret it almost instantly and possibly for the rest of your life.

Jumper the single 6 volt battery in parallel with one of the other 6v batteries so that you have a series-parallel connection of three batteries which still provides 12v but now have 1/3 more capacity.

Be very careful when connecting batteries. They contain an amazing amount of energy and rate a great deal of respect.
 
Fighterpilot wrote:
I guess my configuration would sort out to two start batteries and two 6v for house--recognizing that if one house battery fails I am now at 6 volts. But since I am not living in it or spending more than a weekend at a time in it I guess I could jumper cable from a start battery if I needed to.
*
Yikes,*Oh no!!* Good catch Rick,

You can not jumper your 12 volt batteries to the 6 volt battery.* Unless you want to have 4th of July early??* You could disconnect both 6 volt batteries and connect the system to your 12 volt set.* But that may not be the best solution for you.* I don't know if having mixed voltage*systems is a good idea if you are not totally comfortable with it.* Simple may better for you in this case?*

(Just to clarify, I was talking about 30 ft gillnetters and our boats were outfitted with just the*two six volt batteries total.* You lose one and you can't start the engine.* So we replaced them with two 12 volt batteries and either one would start the engine.* Other than radio, lights and radar, all*other systems were either diesel or Hydraulic.)

Larry B*
 
Flywright

Why not hire the gorilla yard*guy to replace the 8Ds you already have? I have 3 new 8Ds done that way, it was no big deal and quite reasonable price wise. You'll be good for another 8 years. No iffy re-wiring or hand wringing over a new set of hopefully set up correctly batteries.
 
sunchaser wrote:
Why not hire the gorilla yard*guy to replace the 8Ds you already have?
That's probably the best advice so far. It works and it provides*cash flow*for the yard so it will still be around later when we need it.

When I started in this business I cringed at some of the costs that I thought could be reduced through*clever work arounds. Then I*learned that keeping good contractors and yards in business was the best work around there is.
 
RickB wrote:
Jumper the single 6 volt battery in parallel with one of the other 6v batteries so that you have a series-parallel connection of three batteries which still provides 12v but now have 1/3 more capacity.
HUH?* Not likely.

Your watts will still be limited by the single 6 volt battery in series.*


-- Edited by bobofthenorth on Thursday 8th of December 2011 06:36:54 PM
 
bobofthenorth wrote:HUH?* Not likely.
Your watts will still be limited by the single 6 volt battery in series.*

*That is just like saying no battery can have a larger capacity than any one of its cells.
 
AN 8D deep cycle batt is so large it should have enough surface area to start, even 50% discharged as a 24,27, or 31.

Most starters are actually 9V motors and do work fine, given enough amps. .

Our setup is 2 -8D , starting a 6-71 , but we don't operate much in real cold.

On most cruising the engine is started in the single batt that has been powering the house loads all night.

It is left as a single for the first couple of hours , to get the fastest charge from a large frame truck alt , 135A.

After 2 -3 hours the batts are switched to both , and after the engine is secured the "other" batt is selected alone for the evening.

Off season, With a solar panel, the setup sits just fine for 6 months in the both position.

KISS




-- Edited by FF on Friday 9th of December 2011 05:03:40 AM
 
RickB wrote:bobofthenorth wrote:HUH?* Not likely.
Your watts will still be limited by the single 6 volt battery in series.*

*That is just like saying no battery can have a larger capacity than any one of its cells.

*Electricity 101 - amps are constant in a series circuit.* You can have all the "capacity" you like but you can't use it.* What will actually end up happening if you leave the 2/1 parallel/series configuration for any length of time is you will be buying 2 new batteries.*
 
bobofthenorth wrote:*You can have all the "capacity" you like but you can't use it.
One last time just because I am in a good mood.

CAPACITY CAPACITY CAPACITY

A single battery can run a 1 amp load for X amount of time.

Two batteries supplying the same load it will run it for twice as long.

If you add another battery it will run for three times as long.

It is like adding a third fuel tank, the fuel line may be the same size and the engine burns the same amount but adding another fuel tank means it can run longer.

Was that clear enough or do I have to* dumb it down further?
 
I'm sure happy I*have*8 Trojans rather than 1, in the old days I could go for a week of partying with that supply.


-- Edited by sunchaser on Friday 9th of December 2011 07:28:51 AM
 
I understand the "Yikes", no don't do that advice. When I talked about jumper to the house side I was thinking disconnect 6 volt system and than jumper to the 12 volt.

As far as "yard man" labor our dock is 23 miles from the nearest yard and than it is 50 to 70 dollars an hour so am reluctant to go that route.

Going to have to take out a leaking 125 gal. fuel tank so will probably do the batteries at the same time. Batteries on outboard side of the 3208 and the tank sits aft of the eng/tx on the same side.
Christmas project when son-in-law is home. Plan now is cut the deck and pull out the tank, than with the tank platform to work on can get the batteries aft to it and slide them back and lift out the the same cutout. Anythoughts?? Thanks
 
sunchaser wrote:I'm sure happy I*have*8 Trojans rather than 1, in the old days I could go for a week of partying with that supply.
*What's that have to do with batteries?*
biggrin.gif


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RickB wrote:sunchaser wrote:I'm sure happy I*have*8 Trojans rather than 1, in the old days I could go for a week of partying with that supply.
*What's that have to do with batteries?*
biggrin.gif


*

*A few more and he would have a football team. ;-)
 
I do, of course, have a minor redirect to this thread...

If the weight was not a factor, meaning I can likely get them in the place they will go, would there be any advantage to using two 4D cells for my house bank over the four golf cart batteries I currently use?
 
GonzoF1 wrote:
I do, of course, have a minor redirect to this thread...

If the weight was not a factor, meaning I can likely get them in the place they will go, would there be any advantage to using two 4D cells for my house bank over the four golf cart batteries I currently use?
*Keep in mind the 4D's are not true deep cycle where as the golf cart 6V are.
 
sunchaser wrote:
Flywright

Why not hire the gorilla yard*guy to replace the 8Ds you already have? ...
Sunchaser, got the wrong pilot here.* The OP is Fighterpilot.*

Mine were changed out to GCs last spring.* Here's a link to FP's original post on this issue.*

http://www.trawlerforum.com/t42382331/34lrc-battery-location/

Fighterpilot, is the boat you were discussing in this link as the first 34 LRC you looked at the one you ended up purchasing?
 
RickB wrote:*
Two batteries supplying the same load it will run it for twice as long.

If you add another battery it will run for three times as long.

........................

Was that clear enough or do I have to* dumb it down further?

You can say it as many times as you like, you're still wrong.* But I really don't care - the OP can decide for himself and I won't be buying his batteries if he chooses to follow your advice.

*
 
JD wrote:GonzoF1 wrote:
I do, of course, have a minor redirect to this thread...

If the weight was not a factor, meaning I can likely get them in the place they will go, would there be any advantage to using two 4D cells for my house bank over the four golf cart batteries I currently use?
*Keep in mind the 4D's are not true deep cycle where as the golf cart 6V are.

*Wait... Then what is this?

http://www.defender.com/product.jsp?path=-1|328|51495|306219&id=857325
 
JD wrote:
*Keep in mind the 4D's are not true deep cycle where as the golf cart 6V are.
4D, 8D, Group 31 are all form factor descriptors.* They say nothing about the technology inside the case.* This is probably a gross oversimplification but I believe the difference is related to the thickness of the plates.* More, thinner plates allows a larger current outflow for a start application.* Less, thicker plates is more suited to deep cycle applications.* But the important takeaway is that the form size doesn't say anything about what's inside.
 
Yea... I get the size thing, but with size comes an increase in volume. They fill that space with more plates. Just wondering if the differences in a 4D versus two golf cart batts will gain enough of an advantage, whatever it may be, to make it worth it. Time to break out Calder's book again. :-D
 
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