Click for Delta Click for Nordhavn Click for Mulder Click for Mag Bay Click for Glendinning

Battery Charger help/question

Discussion in 'Post Yacht' started by Hermen Ferraz, Nov 22, 2017.

You need to be registered and signed in to view this content.
  1. Hermen Ferraz, Nov 22, 2017
    #1
    Hermen Ferraz

    Hermen Ferraz Member

    Joined:
    Nov 5, 2017
    Messages:
    46
    Location:
    South Florida
    So i think my battery charger is having issues, the boat came with 12V 8A8D batteries and one battery was fully charged but the other wasn’t, granted not by very much the itbwas at 11.80 but still prevented one of my engines to start. I charged the battery of t of the boat. By the way wow what a difficult task and that battery is heavy. Once i put the battery in it started.

    I was given two options either when the previous owner installed these batteries he didn’t adjust the battery charger correctly to the type of battery or my charger needs to be replaced.

    Any comments ideas would be greatly appreciated
  2. Capt J, Nov 22, 2017
    #2
    Capt J

    Capt J Senior Member

    Joined:
    Jul 11, 2005
    Messages:
    14,434
    Location:
    Fort Lauderdale
    11.8 volts is pretty much dead. You need to take a volt meter and see what both batteries are reading in Volts. First with the charger off. Then turn the charger on and see if the voltage goes up on both. The battery charger might not be charging at all. You should see around 12.8 volts if they're fully charged.....maybe 13.2 if the charger is charging. Why wouldn't you just charge the battery in place? There shouldn't be an adjustment for AGM.
  3. Hermen Ferraz, Nov 23, 2017
    #3
    Hermen Ferraz

    Hermen Ferraz Member

    Joined:
    Nov 5, 2017
    Messages:
    46
    Location:
    South Florida
    Thank you for advice I wont have a day off till Friday I will try to do that.

    Honestly this was a mistake due to new to me boat and wasn't 100% sure of what to do, in my previous boats I just had normal marine batteries, this one has AGM which I didn't know how expensive they were until today. You can say huge oversight on my part. Trying to do my own work and learning in the process
  4. Capt J, Nov 23, 2017
    #4
    Capt J

    Capt J Senior Member

    Joined:
    Jul 11, 2005
    Messages:
    14,434
    Location:
    Fort Lauderdale
    AGM's aren't that much more than flooded lead acid, and think of how much time you spend adding water to the batteries over their 3 year lifespan. Most chargers utilize the same setting for flooded and AGM, gel has lower charging profiles.
  5. Hermen Ferraz, Nov 23, 2017
    #5
    Hermen Ferraz

    Hermen Ferraz Member

    Joined:
    Nov 5, 2017
    Messages:
    46
    Location:
    South Florida
    Okay now i see, thank you very much.
  6. ranger58sb, Nov 23, 2017
    #6
    ranger58sb

    ranger58sb Senior member

    Joined:
    Aug 20, 2013
    Messages:
    823
    Location:
    Chesapeake Bay, USA
    Many newer chargers offer several different profiles, sometimes a couple for flooded, a couple for AGMs, a couple for gels, etc... and some even let you custom set the exact voltages so you can match what your battery manufacturer recommends. The ProMariner ProNautic (and the Sterling counterpart) are examples...

    -Chris
  7. Capt Ralph, Nov 23, 2017
    #7
    Capt Ralph

    Capt Ralph Senior Member

    Joined:
    Sep 8, 2004
    Messages:
    12,727
    Location:
    Satsuma, FL
    Just replaced one of two, 2 year old 8D8s on a customers boat. Looked like a bad charger also.
    Bad cell in the one bad battery.
    lil 100 amp battery toaster showed low but fair to good. Never could get a full charge on suspect battery or channel.
    Battery was a bit warm. Worked well for the house but could not start a motor from it.

    500 amp carbon pile load proved the battery was worthless.
    Hydro proved one bad cell.

    Battery charger working fine now.
  8. Hermen Ferraz, Nov 23, 2017
    #8
    Hermen Ferraz

    Hermen Ferraz Member

    Joined:
    Nov 5, 2017
    Messages:
    46
    Location:
    South Florida
    So it has a newer battery charger,

    Mastervolt 40amp Charger put in 2016

    Anyone have an idea if that’s enough i would think it needs a 50.

    Also batteries were put New in 2015
  9. Capt Ralph, Nov 23, 2017
    #9
    Capt Ralph

    Capt Ralph Senior Member

    Joined:
    Sep 8, 2004
    Messages:
    12,727
    Location:
    Satsuma, FL
    I like the mastervolt stuff. 40 amps will do fine. Total up your amp requirments if needed, to ensure your not overtaxing the charger.
    2 month old battery should be checked with this problem.
  10. Capt J, Nov 23, 2017
    #10
    Capt J

    Capt J Senior Member

    Joined:
    Jul 11, 2005
    Messages:
    14,434
    Location:
    Fort Lauderdale
    His boat is 12 volts though. I'd recommend changing all of your DC lighting over to LED, or at least in the salon.
  11. Hermen Ferraz, Nov 23, 2017
    #11
    Hermen Ferraz

    Hermen Ferraz Member

    Joined:
    Nov 5, 2017
    Messages:
    46
    Location:
    South Florida
    That’s in the works actually it’s on the to do list for this weekend.