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Battery maintenance help
Posted: April 21st, 2023, 2:37 pm
by PoppyTortuga
I have a 2004 356 which includes 4 lead acid batteries. Three of the batteries are located between the two main stringers... starting from the genny going aft to the bulkhead is A) genny battery, B) Port engine start, C) Stbd engine start, and finally, the 4th battery (the house) is up on a shelf above the Stbd engine start battery. If you have a 355, 356, or similar you understand the location of these batteries and the difficulty of trying to maintain them. Thus, my question, how do you do it?
Using all my best contortion efforts I can barely see the Stbd engine battery and the house battery is just about impossible to service unless it's disconnected and "brought out into the light". Taking a cell reading, watering (without over filling)... how do you do it? I'm a live aboard and I have to top off at least monthly and I'm getting too old for this task so I'm hoping to find out a trick or two that, hopefully, I've missed along the way.
Note: I've researched the auto watering systems and as far as I can tell they won't work as they require all batteries to be on the same level. Since the house battery is my biggest problem, and it's on a shelf above the others, the solution doesn't seem viable.
Thanks captains... fair winds.
Bob
Re: Battery maintenance help
Posted: April 21st, 2023, 2:58 pm
by Midnightsun
Would like to see what type of lead acid batteries you have, especially the house bank which technically should be the only one requiring an occasional top off then again being a live aboard you are connected to shore power.
Top off systems are normally for spin on cap style fillable batteries which are far and few between unless your house bank consists of 6v batteries where this is common. A typical start battery should not need topping off as it is not really used. The house bank is another story though and will most likely need a bit every 6 months or so.
That being said I have a feeling your shore power charger is not a very good one and is "cooking" your batteries if you need to refill regularly. Something to look into for sure.
Being a live aboard you do need to have the correct charger/converter as opposed to a charger. This explains it pretty well if you take the time to read it.
https://rvtroop.com/rv-converter-vs-battery-chargerI guess what I am trying to say is you may have an older charger that is not doing the job a live aboard requires.
Re: Battery maintenance help
Posted: April 21st, 2023, 8:23 pm
by buster53
Why not look into replacing your batteries with maintenance free batteries. I have a 356 with 3 batteries and I agree, they are difficult to maintain with this 70 yo body, especially the most aft one. I can see maintenance free sometime in my future.
Re: Battery maintenance help
Posted: April 22nd, 2023, 8:47 am
by PoppyTortuga
Midnightsun wrote:Source of the post Would like to see what type of lead acid batteries you have, especially the house bank which technically should be the only one requiring an occasional top off then again being a live aboard you are connected to shore power.
Top off systems are normally for spin on cap style fillable batteries which are far and few between unless your house bank consists of 6v batteries where this is common. A typical start battery should not need topping off as it is not really used. The house bank is another story though and will most likely need a bit every 6 months or so.
That being said I have a feeling your shore power charger is not a very good one and is "cooking" your batteries if you need to refill regularly. Something to look into for sure.
Being a live aboard you do need to have the correct charger/converter as opposed to a charger. This explains it pretty well if you take the time to read it.
https://rvtroop.com/rv-converter-vs-battery-chargerI guess what I am trying to say is you may have an older charger that is not doing the job a live aboard requires.
I read the article, thanks. Before starting my recent trip from NY to Fla I had an electrician replace all my batteries and checked my charging system. All is good. My house battery is a Deka series 31 deep cell. While connected to shore power I use plenty of 12v power that requires the charger to top off the battery, e.g., all my lights, vacu-flush system, shower box pumps, etc. Just take a look at your own 12v panel and you can begin to understand we're drawing/using 12v power enough to warrant battery use and charging as we live onboard. So, I do check it monthly and it does require a top off of water. So, focusing on the "how can this be accomplished easier" considering the location of the house battery is what I'm looking for regardless of how often maintenance happens. Thanks again for your input, much apprecicated.
Bob
Re: Battery maintenance help
Posted: April 22nd, 2023, 8:50 am
by PoppyTortuga
buster53 wrote:Source of the post Why not look into replacing your batteries with maintenance free batteries. I have a 356 with 3 batteries and I agree, they are difficult to maintain with this 70 yo body, especially the most aft one. I can see maintenance free sometime in my future.
Because of the cost. Overall lead acid is less expensive and lasts longer.
Re: Battery maintenance help
Posted: April 22nd, 2023, 9:25 am
by AaHubb
So why not just install two watering systems. The second time you use them you will forget about the cost.
..Aaron
Re: Battery maintenance help
Posted: April 22nd, 2023, 9:27 am
by bud37
Seems like you are caught between a battery and a hard place...

.......just to add, for it to be easy I think moving the problem batteries to an open area with proper ventilation would be the way to go. May entail a cost but the end result may pay back as well maintained batteries last way longer, if they are hard to get at they don't get maintained is my experience...... As I write this it occurs to me this may already have crossed your mind though.....good luck man....
Re: Battery maintenance help
Posted: April 22nd, 2023, 2:17 pm
by buster53
bud37 wrote:Source of the post Seems like you are caught between a battery and a hard place...

.......just to add, for it to be easy I think moving the problem batteries to an open area with proper ventilation would be the way to go. May entail a cost but the end result may pay back as well maintained batteries last way longer, if they are hard to get at they don't get maintained is my experience...... As I write this it occurs to me this may already have crossed your mind though.....good luck man....
On the 355/356, there really is no place else to locate the batteries other than where they are now, located between the stringers. OP has 4 batteries, 2 of which would be a real bear to maintain. I have 3, 2 aren’t bad to get at, 3rd is difficult but doable.
Re: Battery maintenance help
Posted: April 22nd, 2023, 2:29 pm
by buster53
PoppyTortuga wrote:Source of the post buster53 wrote:Source of the post Why not look into replacing your batteries with maintenance free batteries. I have a 356 with 3 batteries and I agree, they are difficult to maintain with this 70 yo body, especially the most aft one. I can see maintenance free sometime in my future.
Because of the cost. Overall lead acid is less expensive and lasts longer.
I hear you and I agree…I like my lead acids as well. But there comes a time, maybe replace just that one, almost impossible to maintain battery with a maintenance free one.
Re: Battery maintenance help
Posted: April 22nd, 2023, 2:55 pm
by timeout
I had a 2003 356. After many head bumps, scraped hands, body cramps, etc. suffered screwing around with that battery, I replaced all 4 with AGM's. In addition, because one 31 series wasn't enough to support the domestic needs, I added an additional 31 series in parallel which I housed in a battery box mounted on the removable plywood panel which covers the rear engine battery. To get to the battery under the panel, I had to remove the additional house battery, but it was easy in that it was easily accessible. Before adding the additional battery, I checked with the battery charger manufacturer to make sure of compatibility with AGM's and if it had enough oomph to handle the additional battery. AGM's are a little pricey, but when you're contorted down there, wishing great harm to come to the engineer who decided that was the best spot to put that battery, it seems worth it. If I still had the boat I would look into Lithium, but I'm not sure where that technology is at these days.Good luck to you.