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Fighterpilot

Senior Member
Joined
Apr 17, 2011
Messages
380
Have searched forum but still need some guidance. This is a continuation of my search for a solution.
Boat is 34 Californian LRC with a pair of 3208N and two 8Ds. One 8D has failed--got it out, the other 8D will come out when we take out the fuel tank to repair or replace in the next month or two. Batteries are on outboard side of port engine and nearly impossible to get to. To check the water on the aft battery need to use mirror and flashlight. Going to replace with a smaller form, pairs for starting, and another pair for house. Don't use for live aboard or more than a few days at a time. Have generator but would run small refrigerator some. Need to limit length to 11 inches to fit in existing boxes.
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Thinking two 12 volts in parallel for start and two 6 volts in series for house. To AGM or not is one of my questions. Sams has AGMs at $100.00 each that would work in the 12 volt series. Duracell now has the business at our local Sams.The deep cycle pair would would not offer as much Ahrs as a pair of 6volts but would probably suffice. A pair of West Marine 800 Seavolt, which would give* similar cranking amps to the AGM pair I would use is actually more expensive so it appears the AGM option is not all that much more in cost, but to stay at the $99.00 each AGM cost I give up some Ahrs. for the house side. Considering the location of the batteries and difficulty of adding water the AGM has some pluses going for it. The boat battery charger is a large Guest system. Understand should not mix flooded and other types of batteries.
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Should I consider AGM or stay flooded with a pair of 6 volts and the highest CCA flooded I can find that will fit within the 11 inch length limit? Cost either way doesn't appear to be a big factor in this case. Sams has EGC2 for $89.00 and the GC2 for $79.00. May have to go with West Marine Seavolt to get CCA wanted and stay within length limit but it is $125.00. Need a pair I believe. AGMs wuld be $100.00 each.*

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Our boat's original battery setup was a pair of 8D's each in their own battery box. Since on our boat pushing a start button combines both batteries as long as the start button is pushed, we really didn't have a "start" and "house" battery. Either battery could perform either function. The only important thing we had to remember was to put the battery selector on 1 or 2 after engine shutdown so we wouldn't inadvertently draw down both batteries with house loads (we put the selector on All when we were running).

As the 8Ds weighed a ton and were a pain to get in and out, last year we took our electrical shop's advice and switched to six 6vdc golf cart batteries. Since three of these will fit into an 8D battery box, no physical modifications were needed to the boat. The batteries are wired in pairs to get three 12vdc "banks." Two of the banks are connected together and then to the original leads that used to connect to the port 8D. The other pair of golf cart batteries are connected to the leads that used to connect to the starboard 8D. So no changes in the boat's wiring were necessary.

The two "banks" connected to the port leads now comprise our house battery, and as such they provide about twice the amp hours as the one 8D used to. The single bank connected to the starboard leads is now the "start" battery and they have about the same amp hour power as the one 8D had. The start combiner relay was left in place, so whenever a start button is pushed, all six batteries are connected together as long as the start button is engaged, same as before.

So we gained twice the house power amp hours, retained the same amount of "start" battery power, we have batteries that are much lighter and easier to get in and out than a giant 8D, and no modifications were needed to the battery boxes or the boat's wiring.
 
If it's that hard to check the water in the aft battery, I'd be looking at AGM's for that reason alone. If it would be any help, AGM batteries can be mounted on their side.
 
I **think** (someone correct me if I'm wrong) that you can draw down the AGMs a lot more than the deep cycles (which you don't want to take down below 50% on a regular basis).* So you may end up with more useful capacity on the AGMs.

Do you have proper charging for the AGMs?* Both your house charger and your engine alternator regulator should have a lower bulk charge voltage for AGMs.
 
6 six volts is an interesting suggestion but would have to be AGM since checking water would be a problem. Will have to check costs. Leaning towards AGM due to water issue. Not sure about the proper charging for them. The charger isn't a Guest-I had a senior moment when I said that. I have a Guest Galvanic Isolator but the charger is by Newmar, which provides multiple battery charging capability while maintaining battery bank isolation. At least that is what the front page on the literature says. Calibrated to maintain a battery at 13.4 volts. Nothing is said about types of batteries. In 1983 did they have AGM batteries? If I were to replace the boat charger what brand and number would suffice for a setup as we discussed? I have a ProMariner-ProSport 12 that is brand new that I never installed in a previous boat which talks to working with flooded and AGM batteries. It addressed two batteries but could I assume two 6 volts in series would equate to one battery? And a pair of 12 volts in parallel for starting would equate to another battery? Hence "two batteries" for the Charger to see? Thanks, keep the advice coming.
 
Our 26-foot cruiser with 260 hp Volvo 44 diesel has AGM batteries for house and starting banks, somewhat like what you're considering.*

A pair of 12V WM SeaVolt group 31's in parallel for house, 105 AH each, model number 8A31DT.* They had their 11th summer this year, some 700 days of cruising, including anchoring w/o generator 2/3 of the time, and seem to be in good shape to continue to work well next summer.*

These WM batteries are actually East Penn Mfg's Deka Sea Mate dual-purpose AGM's, available under many different labels from industrial battery suppliers at prices as low as 2/3 of WM's price. Highly recommended.* A pair of these in the 6V model could keep length under 11 inches.

For seven years we had a pair of 12V Optima AGMs in parallel for starting, and then replaced them with Deka Intimidators.* Both are group 34 size (small and only about 40 lb each), and optimized for starting rather than deep cycle use - lots of CCA (785 each), not so many AH.* Highly recommended.

Sears Platinum AGM's, really Odyssey, are another high-quality choice.

For best results in extended cruising and anchoring, we have a Balmar alternator with separate Balmar MC-612 regulator.* This provides the most desirable charging voltages for best performance and longest life of our house bank.* Our Heart Freedom 10 inverter/charger has an AGM setting as well.

You might be fine with ordinary alternator charging parameters.* Certainly the starting-type AGM's do OK with ordinary alternators - the Optimas in my diesel truck are 10 years old and still going strong.* I'd sure suggest replace the old Newmar charger with a modern multi-stage charger, however.


-- Edited by RCook on Wednesday 28th of December 2011 07:58:23 AM
 
Newmar makes wonderful chargers. Their Phase Three are really wonderful reliable chargers. If you have any questions about charging batteries call or email Kap Kaplan at Newmar. He knows what he's talking about and is a really nice guy. Yes batteries connected as you suggest would be seen as a single battery by the charger. It's common to refer to them as a "bank" of batteries.
 
Fighterpilot wrote:
*I assume two 6 volts in series would equate to one battery?
*No, they're still two batteries but when two 6 volt golf cart batteries are connected in series the pair produces 12 volts and about the same amp hours as a single 8D.

The typical 8D battery box will hold three 6vdc golf cart batteries.** So if you have two 8D boxes you can install six golf cart batteries, or three pairs.* You can assign the pairs however you want, house or start.
 
I guess what I should have said was it equates to 1 twelve volt battery even though it is 2 batteries. My 8D boxes only accomodates the 20 and 3/4 inch battery and most 6 volts I have seen are 7inches plus in width so I can't get three in the existing boxes. Will have to live with two and put a spacer in the box to hold the two in place.

Have decided to consider an inverter since would like to be able to turn on the tv and the dvd for the grandkids without cranking up the old genny. That consideration suggests the 6 volts for greater amphours is the way to go. Leaning towards AGMs since access for water addition is so limited. Now will have to sort out the inverters. If I go with AGMs will have to have a new charger as well. Do I buy a charger/inverter combination or keep them separate. Inclined to keep separate to avoid losing both if one side go bad. Wow, BOAT--bring over another thousand.
 
I might look at an easier way to fill the batteries. I bought a jug that I fill with water and just put the nozzle in the battery fill hole and it automatically stops the water flow when full. (http://www.amazon.com/Plews-75-030-Capacity-Plastic-Battery/dp/B000RFUF12) There are also a number of systems like Pro-fill and Quik-fill that have caps and hoses so you can fill without having to squeeze back there to physically look at each cell or take the caps on and off.

Ken
 
Scooter is a Californian 34 that had 2 8D's on stbd side for engine start & anchor winch. Also had 4 6v golf cart batteries on port side for house bank. Wiring was such that they could also be used to start engines if needed. All batteries were lead acid. Inverter is an inverter charger used for the house side. There is a dedicated 110v charger for the engine side as well. Servicing was almost impossible due to access behind the engines. Long story shortened up: we replaced everything with 4 8D AGM batteries. Paid the yard muscle to do the moving. Wiring stayed the same, amp hrs improved, service aches & pains went away. That was 3 years ago, no problems so far. Incidentally, most of our time is spent at anchor, running computers, Norcold refrig, lights etc.
 
Give up on the AGMs. Charger and alternators would have to be replaced and have found a starter battery by west marine that is "maintenance free". They don´t say it is AGM so assume it is flooded, but still wonder about the maintenance free part. Since the starter batteries are the most inaccessible will use their batteries, 800 MCA in parallel and the standard golf cart pair in series for house. They are accessible enough to service now and than. 2bucks suggestion seems doable for battery service so will go with that. After further consideration will go with inexpensive inverter to run the tv/dvd and use 12 volt feature of the refrig.

That WM battery, made by East Penn must be available from other vendors and could be cheaper than WM. Does anyone have a suggestion about source or opinion on my latest thinking? Thanks
 
There are other solutions to a builders stupidity.

One is an automatic battery watering setup, the other is Hydro Caps , made to convert the gas given off during heavy charging back to water.

WE use Hydro Caps for 20+ years and they do cut batt watering be 80% or so.
 
Found another source for "maintenance free" starter batteries at Sams, but the 6 volt house batteries will need service now an than. Hydro Caps sounds like a good idea--any good source for them? The 6 volt batteries at Sams has a different type of cap system on them. Looks like they are all interconnected and moving a lever unlocks them all. Will have to examine the hydro cap to see if they will fit this set up.

Next question-- wiring the batteries together. Presently the leads from the switch and to the engines looks like 4/0. They are big. For the 1 foot to 2 foot runs needed to hook the batteries together to make a bank can I use marine, tined, copper 2/0 wire which I have. I'll have to run - to - and + to + on the starter set. Should be less than a foot in distance for each. On the house set will have to run + to - on one side. Again about a foot. No big loads on the house set. Not a live aboard or big inverters involved. Start is for 3208N. About 632 cu. in. engines. Each of those batteries will be 800 CCA, or Ref CA of 960, parallel configuration. Thanks
 
Fighterpilot wrote:
*The 6 volt batteries at Sams has a different type of cap system on them. Looks like they are all interconnected and moving a lever unlocks them all. Will have to examine the hydro cap to see if they will fit this set up.
*My 6 volts (Interstate) have that same gizmo, but it just replaces the standard caps.

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I used a small garden sprayer/waterer that you pumped up. The nozzle could be set to stream rather than the spray. I think it held about 1 gallon of water. It worked very well to add water to my 4 - 8ds. and kept the work and dribbling from other means to a minimum.
I could not use a typical car or industrial battery watering jug. There was no room.

If you go that route the only caveat would be watch when you pull the trigger as the stream could be enough to cause blowback. I quickly learned to feather the trigger and not pump so much pressure.
 
As found on google in under a second,

hydrocapcorp.com/info.htm
 
2bucks wrote:
*I bought a jug that I fill with water and just put the nozzle in the battery fill hole and it automatically stops the water flow when full. http://www.amazon.com/Plews-75-030-Capacity-Plastic-Battery/dp/B000RFUF12
We use the same jug as Ken and it works great.* While our batteries are not tucked back under something they are a long reach from the easiest position to be in the engine room.* The jug makes topping the cells off easy and quick.

Carey of this forum has batteries that are tucked back under the side deck of his boat.* He can reach them but can't look into them.* I believe he uses the same jug and it works as advertised.
 
I think I have one of those jugs up in my barn. Will check and see if it will fit the 6 volt batteries which will require servicing. Appreciate the reminder.
 
you can buy those jugs at knappa auto for about 11 $ they work on 6 and 12 volt

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The question regarding 6 volt was because the 6 volt that sams sells has a one piece system that covers all holes. Not sure if the holes are of a size to work with the filler.
 
Our 6vdc batteries have a frame and lever system that contains all three caps and the lever expands or contracts the cab bases with one squeeze. Don't know if that's the sort of thing you mean by a one piece system but the fill holes on our 6vdc batteries seem to be the same diameter as the ones on our old 8Ds. At any rate the fill jug neck fits them just fine.
 
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