Battery recommendation

Aug 24, 2016
45
Hunter 1981 Hunter 27 Saint Petersburg, Florida
I'm thinking of changing batteries since they came with a boat. Thinking it's somewhat cheap and easy fix just to be sure that I have full power to run the boat and start the engine. I'm hoping to do it my next day off so I'm wondering what people have as a battery setup or recommendations. This is hunter 27 1981. I have battery plus, walmart, and West Marine as my choices around me. Again, I'm trying to do the swap on my day off so not planning on ordering online. Does everybody just have one starter and one deep cycle? And which type would be good for both? Thanks
 
Jan 7, 2011
4,727
Oday 322 East Chicago, IN
My first boat was a Hunter 280. It came with 2 batteries...Group 24's.

I day sailed her mostly, and was on shore power when not being sailed. She did not have refrigeration, so her power needs were very modest...VHF radio, stereo, cabin nights and instrumentation, including auto pilot.

I replaced her batteries, that were a bit tired with 2 new "deep cycle marine" batteries from Menards...I don't recall the brand. For my modest power needs, they worked fine and were cheap.

When I needed to replace the batteries on my O'Day 322, again mostly day sailed, but with refrigeration, I went with 2 group 31's, also deep cycle marine batteries from Menards.

They are certainly not the best batteries you can buy, but they meet my needs and were cheap. I use the. To start the boat (Yanmar 2GM20F) as well as for electric when sailing. I have spent a few single nights on the hook, using only 1 battery overnight, and they seem to work fine.

If you are spending many nights on the hook or have higher power needs, you should invest in something better, but for my needs, these work just fine.

Good luck,

Greg
 
May 24, 2004
7,129
CC 30 South Florida
Batteries can be unpredictable and that is why they revolve around a warranty system. A brand new battery can fail while an old neglected one may refuse to die. My point is that just because the batteries came with the boat is no reason to replace them at this time. The simplest way to test them is to take them down to the nearest auto parts retailer and have them tested on their diagnostic computerized tester. A voltage reading with the batteries fully charged and rested will give you an idea of the remaining capacity in Ah. Full capacity is around 12.6V while 70% capacity is 12.3V. Anything less than 12.3V at rest you may as well replace them. Now for an h27 the simplest and most inexpensive setup is 2 Group 27, wet cell, deep discharge batteries. You do not need a starter battery as the deep discharge batteries will easily start the small diesel engine. This way you will have two identical batteries that can be used to double the house bank capacity or serve as back up to each other. What I would do is to connect them through a 1,2,Both, Off Battery switch. I would alternate the use of each battery in consecutive outings to maintain the other one in reserve. If you carry a battery booster pack then you could combine in Both to have a larger more efficient bank but do not compromise redundancy an always have a backup. With the switch when you choose #1 or #2 that is the battery that will service the loads and also receive charge from the alternator. Once the engine starts the you could switch to Both and charge both batteries. There is a lot of material to learn about batteries and their use. A cruising sailboat will have different needs than a day sailer.
 
Nov 8, 2007
1,523
Hunter 27_75-84 Sandusky Harbor Marina, Ohio
A lot depends on your load at anchor overnight. Our only load is the radio, the cabin and anchor lights, so a single deep discharge wet cell does fine for us over the past 17 summers. I don't remember it's capacity. We buy at West Marine, paying a small premium for convenience, and their boating experience.
 
Oct 6, 2007
1,023
Hunter H30 1982 Chicago IL
I've been using a pair of Group 27 deep cycle flooded batteries. One of them will start the little Yanmar 2GM with no problem, my loads are pretty minimal and I have shore power with a battery charger. I am getting three to four years life out of them. Of course, up here they are disconnected at least five months a year for winter storage. Sorry, I don't recall the brand or manufacturer. I've actually been buying them through my yacht yard and having them put the batteries in place to save time and, more importantly, my back.
 
May 11, 2014
34
Catalina 310 Lake Texoma
I wish someone had shared the information at the attached link with me when I moved up to boats with alternators, battery banks and battery switches. Maine Sail puts the basic information in context and reading it helped me to understand much better what I had, why the builder/PO set it up as I found it, my needs and my basic options, (independent of the boat owned).

http://forums.sailboatowners.com/index.php?threads/1-both-2-off-switches-thoughts-musings.137615/

Good luck and let us know what you end up deciding.
 
Mar 5, 2012
152
Hunter 37-cutter Saint Augustine
Ko, battery choices are very dificult to chose from there are so many types on my boat I run 2, 4d deep cylcle batteries and one 31 series for a starter. all are lead acid they are cheap and last to four years depending on how you care as for the gels they last longer but cost morealmost twice.so price is really about the same in the long run. when I had my 28 cal, I used two 27 series and they lasted five years for the two.also on my boat. I switched all light to led,s and only need power to run fridge and at times a microwave or the wife needs hair dryer via an inverter. I do not stay out long on the hook and when I need to I start the motor to charge the batteries via a 105 amp alternator
 
May 24, 2004
7,129
CC 30 South Florida
A lot depends on your load at anchor overnight. Our only load is the radio, the cabin and anchor lights, so a single deep discharge wet cell does fine for us over the past 17 summers. I don't remember it's capacity. We buy at West Marine, paying a small premium for convenience, and their boating experience.
I hear you David and indeed a single deep discharge battery can service the OEM electrical needs of the h27. My point regarding the use of two batteries is to be able to provide backup for engine starting. Batteries do fail and sometimes rather quickly in a matter of hours. The addition of a 2nd battery besides peace of mind does provide some more options on the uses of power. Although I cannot argue with 17 seasons of experience without a hitch. I personally like wet cells as they are rather inexpensive and I can get off the boat and find a suitable replacement almost anywhere. The OEM alternator for the 1GM is 15A and the engine with 6HP would loose too much power if it attempted to drive a higher output one.
 
Nov 8, 2007
1,523
Hunter 27_75-84 Sandusky Harbor Marina, Ohio
I hear you, Benny. Our H27 has room for two batteries, and a 1-2-both-off switch, so using two would be easy. But I love simplicity, and going to two might mean shore power charging - real complexity to do right.

The Admiral and I are comfortable relying on the sails as backup power. I have docked under sail twice after engine failures, once on our H27, and again on our friend's H30. But this is clearly up to personal preference, and a second battery is a very reasonable contingency plan.
 
Oct 6, 2007
1,023
Hunter H30 1982 Chicago IL
I hear you, Benny. Our H27 has room for two batteries, and a 1-2-both-off switch, so using two would be easy. But I love simplicity, and going to two might mean shore power charging - real complexity to do right.

The Admiral and I are comfortable relying on the sails as backup power. I have docked under sail twice after engine failures, once on our H27, and again on our friend's H30. But this is clearly up to personal preference, and a second battery is a very reasonable contingency plan.
David,

Dual batteries provide a backup power source not only for starting the engine, but for radio communication, navigation electronics, depth meter, bilge pump(s), etc. They're cheap insurance. Like you, I also like to keep things simple, and I added the shore power "smart" charger only five or six years ago. Prior to that, battery charge was maintained by the alternator, conscientious use of the battery 1/2/both switch, and judicious use of cabin lights and stereo, so it is possible to have two batteries without a shore power charger. Eventually though, I came to a point were I was spending every weekend on the boat and just wanted to be comfortable without worrying about running down the batteries. The shore power charger aleives that worry, which is a slightly different definition of simplicity.
 
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May 24, 2004
7,129
CC 30 South Florida
David I don't know what year your boat is but I believe in most models whether Renault or Yanmar powered the engines could be hand cranked. Having a crank handle could help simplify things.
 
Oct 22, 2014
20,995
CAL 35 Cruiser #21 moored EVERETT WA
Benny, I have heard of handcranking a diesel. Never seen it done. Is it like a Modle T? Do you have watch out for the handle when the engine fires?

David. You are going to spend money on the boat. It is a foregone conclusion. At the least spend some on things that will help get you safely home when Murphy arrives to mess up your day.
2nd battery, handheld VHF, the better life jackets.
 
Jun 2, 2004
5,802
Hunter 37-cutter, '79 41 23' 30"N 82 33' 20"W--------Huron, OH
My battery system is much like MaineSail recommends except cables not quite as beefy. Going from four AGMs to two 6-volts in series saves me about $900. when time to replace. I lose about 140 amp-hours by comparison, 225 Ah for two $80. batteries versus 360 for the four AGMs at over $225. each. And I use a lot less space on the boat, opened up a lot of aft locker space because these are in the bilge. Do have one small start battery in the locker as backup. Oh, and good luck starting a diesel with a hand crank. Takes two, someone to hold the compression lever open while someone else spins.
Batts.Apr2012.jpg
 
Aug 24, 2016
45
Hunter 1981 Hunter 27 Saint Petersburg, Florida
So, after reading that article about batteries I'm leaning now towards the 2x6v golf cart batteries. But I want to have a 12v backup so if I'm replacing 2 house batteries with golf cart batteries, should I just do 2x6v series wired batteries and then parallel wire to it 2 more series wired golf cart batteries? That way I have equivalent of 2 12v batteries. I like the golf cart battery idea since they seem to be the true deep cycle batteries. Also as far as charging from alternator or ac battery charger for this set up. Is it wired the same way as 2 12v batteries?
 

SFS

.
Aug 18, 2015
2,066
Currently Boatless Okinawa
Kommy, lots of threads on this topic, including one in the past two weeks. Search is your friend here.
 
Mar 5, 2012
152
Hunter 37-cutter Saint Augustine
again lots of input, make it simple get two 24.or 27 a battery switch run one for haouse other for start,these batterys can be found anywere in the world and you can buy pricey ones or just go to wally world and buy on the cheap.the lead acid will last about 3 years, either way researchand what you feel comfortable spending keep both charged and when on the hook switch to one battery and when that one goes low the other is fully charged
 
Jun 2, 2004
5,802
Hunter 37-cutter, '79 41 23' 30"N 82 33' 20"W--------Huron, OH
So, after reading that article about batteries I'm leaning now towards the 2x6v golf cart batteries. But I want to have a 12v backup so if I'm replacing 2 house batteries with golf cart batteries, should I just do 2x6v series wired batteries and then parallel wire to it 2 more series wired golf cart batteries? That way I have equivalent of 2 12v batteries. I like the golf cart battery idea since they seem to be the true deep cycle batteries. Also as far as charging from alternator or ac battery charger for this set up. Is it wired the same way as 2 12v batteries?
The two 6-volt option is my favorite. Then a cheap group 24 12V for a start backup. Charging from shore can be as simple as a little charger with two outputs, one for the house bank and one for the backup. Just run an extension cord to a 15 amp outlet. If your dock only has 30 amp connectors you will need an adapter to your extension cord. There are maybe better options but they tend to be a lot more costly.
 
Jun 5, 2010
1,107
Hunter 25 Burlington NJ
I have never understood the benefits of the two-6-bolt option. What I do understand are the drawbacks:
  • heavier wiring, and more of it (more expensive, more complex)
  • inability to take one bad unit out of the system (one bad = both unusable. Compare to having two 12-volts)
  • expense in purchasing, when compared to discounters of decent stuff like Batteries Plus
  • difficulty in finding replacements without waiting for regular retailers (WM) to order and receive non-stock items
  • scary possibility of owner or unfamiliar tech wiring them wrong (pos-to-neg reversal = kaboom)
  • excessive weight, especially when one can't locate two units P & S on small boat
Maybe someone kind and patient will explain it to me with practical science (not techies' dreams) and hard numbers, in view of the above, for the elucidation of me and everyone else pondering this thread. o_O