Battery Plan for Beneteau 43

DPW

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Feb 9, 2017
38
Beneteau 43 Hingham, MA
Hi - First time owner, but sober for 6 moths;-)
I have read everything I can find on battery charging and maintenance for marine AGM batteries and am more confused than when I started.
When I purchased the boat last summer I had the yard add new batteries, they opted for West Marine AGM Group 27, including: House - 198AH@20hrs; Engine - 105AH@20hrs; Bow Thruster - 92AH@20hrs. I picked up the boat in Deltaville and sailed her to home port in Boston. On the way the alternator failed and we installed new Hitachi 80 AMP in Newport. All seemed well until late summer. We have her on a mooring and at some point it didn't matter how long we ran the diesel to charge the batts they would not seem to top off and the engine bat ("Deep Cycle" AGM) began to fail. I removed the batts and they are in my basement for the winter.
1) What should I do to ensure the most effective/efficient charging of the batts while mooring?
2) What is proper care in winter?
3) Do I have the right battery set up for a 2009 Beneteau 43?
Thanks for any info.
 
Jan 4, 2010
1,037
Farr 30 San Francisco
I think Maine Sail has a special dislike for Hitachi alternators. The issue is the charge voltage is too low as I understand it. What you want is an alternator that has the ability to sense the battery voltage, and the battery temperature at the battery, and control the charging based on that info. The internal regulated types are too dumb.

Also it seems AGMs are more particular about being undercharged
 
Jan 4, 2010
1,037
Farr 30 San Francisco
Please search around the forums, trust what Maine Sail writes, and if I garbled his opinions about Hitachi alts my apologies
 
Jan 22, 2008
8,050
Beneteau 323 Annapolis MD
To start with, the batts should be fully charged before being taken home for the winter. Less than full charge, they could possibly discharge and ruin them. If fully charged, they can be left on the boat. /// As I'm sure you will be reminded, there are better buys to be had at Sams Club and the like. /// I don't know it all, but I can't help but wonder how there are three different amp ratings if they are all 27s? Maybe I'm just not on board about AGMs, though. /// Wisdom has it that all batteries should be - for best charging regimens- the same, and manufactured in the same month. /// I have 3 size 31s on my B 32.
 
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Gunni

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Mar 16, 2010
5,937
Beneteau 411 Oceanis Annapolis
Your alternator charge source is inadequate and "dumb", meaning it is not monitoring your battery bank(s). On mooring you really need a properly controlled charge source, solar or wind. Now would be a great time to interview qualified and ABYC-certed marine electricians and come up with a system plan and related budget. Do this now while you are in the off season and the tradesmen are at lower demand.
 
Jan 10, 2017
6
Beneteau Oceanis 45 Myrtle Beach, SC
Your house battery is a 4D AGM. You may have two if the previous owner had the optional 2nd battery added. The starting battery is a Grp 27 multi purpose deep cycle/starting battery and the bow thruster is most likely one or two grp 24. On our 40, we replaced the standard 80 amp alternator with a 150 amp alternator and a smart voltage regulator. This meant we could charge our batteries in 4-5 hrs. under 2450 rpm instead of 8-10 hrs. with the 80 amp alternator. We also added solar cells to charge the batteries on the mooring/anchoring and during winter layup. If your batteries are out of the boat and at home, then if they are on a concrete floor, place wood underneath them and put a car charger on them once a month to top them off. If I kept my Ben 40, I would have changed the v-belt to a serpentine belt to take full advatage of the 150 amp alternator.
 

DPW

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Feb 9, 2017
38
Beneteau 43 Hingham, MA
thanks all for the responses. Likely will opt for Balmar 100 amp alt with external regulator and add solar. Ordered a battery charger for the winter charging, hopefully the batteries are not ruined but if so they are less than a year old so West Marine should replace them.
 
Dec 2, 1999
15,184
Hunter Vision-36 Rio Vista, CA.
Before you invest in a Balmar check with Maine Sail. He may have some other options.
 
Jun 15, 2012
694
BAVARIA C57 Greenport, NY
Have same problem on my 2007 Hunter 41, Hitachi alternator will not properly charge the batteries. I solved problem by installing a generator (which of course has other uses). When running generator it automatically powers shore charger, which charges batteries correctly. If you have any thought of generator install, you may want to use the upgrade alternator money towards the generator install.
 

DPW

.
Feb 9, 2017
38
Beneteau 43 Hingham, MA
Have same problem on my 2007 Hunter 41, Hitachi alternator will not properly charge the batteries. I solved problem by installing a generator (which of course has other uses). When running generator it automatically powers shore charger, which charges batteries correctly. If you have any thought of generator install, you may want to use the upgrade alternator money towards the generator install.
i would like to learn more about generator install: is it DIY, what type of generator, cost? thanks
 
Jan 10, 2017
6
Beneteau Oceanis 45 Myrtle Beach, SC
I also installed a 5.5 kw NextGen generator on my Ben 40. If you are doing long distance cruising and staying away from docks, then consider it. Otherwise the cost effective way to charge your batteries is with a more efficient larger capacity alternator and smart regulator. For occasional cruising and winter storage, then consider solar cells. The diesel genset based on its capacity will run from 4 thousand to 8 thousand US dollars with a self install. It also requires a basic knowledge of AC and DC currents, current rules for installation and plumbing the cooling system. Think twice before taking this path.
 
Jun 15, 2012
694
BAVARIA C57 Greenport, NY
DPW, I installed a generator myself. Followed carefully Hunters' instructions. If Beneteau offered one from the factory see if you can get the installation instructions that would have been given to dealers. The instructions would help to de-mistify the installation and cost. Once you have a generator you will never want to be without one.