Switching to 6volt golf cart batteries in a hunter 36

Discussion in 'Ask A Hunter Owner' started by ChrisCall, May 16, 2019. Add this thread to a FAQ

  1. ChrisCall


    Joined Mar 27, 2016
    78 posts, 5 likes
    Catalina 30
    US Hingham
    I've got a bad battery in my new to me 2004 hunter 36 . The batteries that are in there are 2 big D4 . I'm I'm thinking of switching to the 6 volt golf cart batteries wiring them in series. Has anyone done this on there hunter ? Did you need to do anything special beyond just wire them in series?

  2. Don S/V ILLusion

    Don S/V ILLusion

    Joined Sep 25, 2008
    5,388 posts, 507 likes
    Alden 50
    US Sarasota, Florida
    All you need is the space. Break out your tape measure.

  3. Justin_NSA


    Joined Jul 7, 2004
    5,713 posts, 1,250 likes
    Hunter 30T
    US Cheney, KS
    That was my reason for not doing it in my Hunter.
    You need twice the space to replace the 2 12v batteries....and the cost!

  4. Stu Jackson

    Stu Jackson

    Joined Feb 26, 2004
    20,599 posts, 983 likes
    Catalina 34
    224 CA Maple Bay, BC, Canada
    Many folks have reported that two 6V golf cart batteries fit in the footprint of one big honkin' D. Much better solution for your back! Wire them properly and you're done. Don's right.

  5. shemandr


    Joined Jan 1, 2006
    4,019 posts, 946 likes
    Marblehead Skiff 14'
    US Greenport, NY
    I was going to do that on my 356 but as I recall the 6v's were taller than the D4's and didn't fit in the battery box. There's plenty of room for a taller battery box but I kinda remember something about moving the fuses or needing new cables. Nevertheless I think it's a reasonable idea and had I kept the boat I might have done it. I think a lot of forum members have concluded that multiple smaller batteries are easier to deal with. Given how finicky batteries can be it may be better not to put a lot of money in any one battery.

  6. Hunter Ad Bot

    Hunter Ad Bot

    Joined Oct 27, 2016
    0 posts, 13 likes
    US Seattle
    Hunter props, shafts, struts, and cutless bearings


    See the product

  7. ChrisCall


    Joined Mar 27, 2016
    78 posts, 5 likes
    Catalina 30
    US Hingham
    Thanks everyone . The batteries actually made my decision for me I went down to the boat and my number one battery wasn't holding a charge . So I went ahead it did replaced them with the 6volt golf cart batteries.

  8. Ron20324


    Joined Jan 22, 2008
    6,933 posts, 880 likes
    Beneteau 323
    US Annapolis MD
    How many 6s do you have?

  9. seadaddler


    Joined Dec 19, 2006
    5,558 posts, 158 likes
    Hunter 36
    US Punta Gorda
    I did change to 4-6 volt batteries and put them under the starboard saloon table and did after I saw some one on here add them same place on 356 and all the heavy cable fit and did not need
    to add any more cable and also added a start battery.
    I have Gen in that same port locker in cockpit and moving batteries starboard help balance out
    my boat and also have2-195 watt solar panels off the arch.
    I even converted my helm winches to electric and also added Ocean Marine Davits on my 2007 H-36.

  10. jeff356


    Joined Apr 21, 2014
    143 posts, 28 likes
    Hunter 356
    US Middle River, MD
    Went through the same decision making process and and got 4 x 125 ah lifelines that I am adding under the starboard dinette table. Going to leave my 2 105 ah batteries in the lazzerette but this should balance out that port lean. Also have a stainless sound shield enclosed 4.2kw gen so this will help out. Also have 75 amp charger to replace the 40 amp to faster charge the batteries when on the generator.

  11. DianaOfBurlington


    Joined Jun 5, 2010
    988 posts, 54 likes
    Hunter 25
    US Burlington NJ
    Will someone please explain to me the most important reasons for using double the number of 6-volt batteries to gain the same amount of volts and A/H? In all my years in this business I have no knowledge of any real benefit.

  12. DayDreamer41


    Joined Oct 29, 2016
    1,343 posts, 669 likes
    Hunter 41 DS
    Un Port Huron
    @DianaOfBurlington there has been extensive testing of batteries related to cost vs life cycle results of which indicate that 6V T-105's provide for higher return on investment compared to a broad field of rechargeable power.

    DianaOfBurlington likes this.
  13. Maine Sail

    Maine Sail Moderator

    Joined Feb 6, 1998
    10,982 posts, 765 likes
    Canadian Sailcraft 36T
    US Casco Bay, ME
  14. Ward H

    Ward H

    Joined Nov 7, 2011
    2,388 posts, 573 likes
    Catalina 30 Mk II
    US Barnegat, NJ
    Great link by Maine Sail.

    Maybe this will help answer your question also.

    12 volts is 12 volts, unless you wire them for 24 volts.

    A Grp 24 Deep Cycle battery is rated at 75Ah. Two in parallel give you 12V @ 150Ah.
    Two 6V GC2 true deep cycle batteries wired in series give you 12V @ 230Ah.

    So two batteries vs two batteries give you 80 more Ahs. The two GC2 batteries combined weight is 38 lbs more than the Grp 24s which means more lead. They are built better and will last longer.

    DianaOfBurlington likes this.
  15. DianaOfBurlington


    Joined Jun 5, 2010
    988 posts, 54 likes
    Hunter 25
    US Burlington NJ
    My argument would be that I have two 75 a/h 12-volt deep-cycle batteries linked together as one bank (usable net about 90 a/h total), made by East Penn (excellent manufacturer who make WM-label batteries), that cost about $124 each (retail; but, being me, I go direct to distribution so...), that I have to replace maybe once every 4 years, so that costs me - at worst - about $63/yr to have onboard power. There are certain thresholds at which I 'stop taking out the toolbox' and that's well within that.

    Also, don't forget that all the wiring connecting the two batteries into one bank will have to be, roughly, double the wire gauge. I may have put the batteries in precisely the best spot in the boat; but that doesn't mean I'd like to add 40 or 50 extra lbs in a 4000-lb 25-footer.

    Also, if one 6v fails, in a 12-volt boat, you have nothing. If one of mine fails, and I'm able to diagnose that properly in time to disconnect them from each other, I still have 40 a/h usable power.

    East Penn have one of the best durability ratings out there.