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Rmack1's avatar
Rmack1
Explorer
Apr 29, 2017

Just upgraded to 6 volt

I have two Trojan T105+ deep cycles that I replaced my old 12 volt boat batteries with. Series wired, off course. I suspect I'll have more amp hours now.

Question; should I do any maintenance on those bad boys?

40 Replies

  • And whiskey tango foxtrot is a 'hydrometer' and how do you get one and use it?
  • BFL13 wrote:
    Rmack1 wrote:
    They supposedly were pretty new. Would running one or both of my gennies hooked up for a few hours top them off?


    No. A gen just supplies 120v to a battery charger. It is the charger that will top them off. If it can.

    If you mean the 12v outlet on a Honda gen or whatever brand, yes BUT you have to watch it like a hawk because the voltage can go way high and you have to stop when it tries to go over say 16.2 volts (Trojan equalize voltage) keep checking the hydrometer.

    Once you have them all the way up, that is your "baseline SG" target for future recharges so you know you are all the way full. At that point you can reset your Trimetric AH counter to zero and start over.


    Thank you for responding.

    What I mean is starting up both of my Yamaha gennies, or one at a time, and plugging them into the side of my TT, for the purpose of charging the two 6 volt deep cycle batteries I just installed on trailer's hitch.
  • Rmack1 wrote:
    They supposedly were pretty new. Would running one or both of my gennies hooked up for a few hours top them off?


    No. A gen just supplies 120v to a battery charger. It is the charger that will top them off. If it can.

    If you mean the 12v outlet on a Honda gen or whatever brand, yes BUT you have to watch it like a hawk because the voltage can go way high and you have to stop when it tries to go over say 16.2 volts (Trojan equalize voltage) keep checking the hydrometer.

    Once you have them all the way up, that is your "baseline SG" target for future recharges so you know you are all the way full. At that point you can reset your Trimetric AH counter to zero and start over.
  • Ed_Gee wrote:
    Rmack1 wrote:
    I have two Trojan T105+ deep cycles that I replaced my old 12 volt boat batteries with. Series wired, off course. I suspect I'll have more amp hours now.

    Question; should I do any maintenance on those bad boys?


    For heaven sakes yes! You must always make sure the acid/water level is kept above the plates in those wet cells. I check mine at least once each month....or more frequently depending on usage. Letting the battery acid get low enough to expose the plates will permanently damage the battery.


    Once a month? That often for new batteries?

    I can just put in purified water to bring up any low looking cells, yes? I did it with my 12 volts. they had slots on the bottom of the ports that you had to keep the water level at. Too much was bad, also.

    I have gloves, a face shield and everything.
  • They supposedly were pretty new. Would running one or both of my gennies hooked up for a few hours top them off?
  • New batteries have been on the shelf and need a charge as soon as you get them home to bring them up to speed. Use an hydrometer to know you have them where they belong. Trojan specs.-- 1.285 for proper full? Whatever Trojan says. It can take a charger that can do 15 or so volts to get them there.
  • Rmack1 wrote:
    I have two Trojan T105+ deep cycles that I replaced my old 12 volt boat batteries with. Series wired, off course. I suspect I'll have more amp hours now.

    Question; should I do any maintenance on those bad boys?


    For heaven sakes yes! You must always make sure the acid/water level is kept above the plates in those wet cells. I check mine at least once each month....or more frequently depending on usage. Letting the battery acid get low enough to expose the plates will permanently damage the battery.
  • 2oldman wrote:
    If they've been bad you should punish them.


    hehe, long time no see.

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