Results 1 to 5 of 5

Thread: Batteries

  1. #1

    Default Batteries

    A couple things about batteries. I think most people run with both batteries on line at the same time. The problem with that is thatís only as good as the weakest battery in your system. Does not charge them both to the same level. Even brand new batteries will have a slight difference in output and capacity. Run your switch on one battery then switch to the other on ONLY WHEN ENGINE IS OFF. This way both get up to there highest potential.
    Keep them clean, always wipe the crude that build up and dirty, any amount of dirt will start a small even if it's very small current path to ground. Cleaning is very very important! Check the water level and only use distilled water.
    For the best results use a charger that pulsates, this turn on and off the charge current and I understand knocks part of the build up off the lead plates in side.
    Always store fully charged, specially in winter!
    Jumper cables in a boat sure why not, but with proper care your hope is to never need them.
    A easy way to see if you have a current draw on the battery even after ever thing is off is to disconnect the positive term and put a test light inbetween the terminal and the battery. If the light comes on there is a completed curcuit some place. Pull 1 fuse at a time till you see the light go off and thats the curcuit with the draw.

  2. #2
    Join Date
    Apr 2006
    chugiak, ak

    Default got a single battery want dual

    Ok, I agree with everything above. I have a single battery right now, but want a dual battery system. Is there a kit out there that I can install, that is simple and reliable. I think I have seen a switch out there that you can switch from one battery to another or turn them completely off. Anyone heard of this?
    Just bought a 20' wooldridge sport, and am new to the aluminum jet boat crowd. I am used to working on big fiberglass offshore racing boats, these are a whole different animal, but am excited to get out and do some jet boating!!!

  3. #3

    Default Switch

    You bet PERKO 850 series makes them, make sure you get the right amperage rating, biggers always better, West Marine or Batterys Plus or Alaska Battery on Dowling/Potter. Polor Wire is a great place too lots of stuff and knowlage.
    Keep the battery cable as short as possible, don't run the cable a long ways unless you have to the voltage drop on DC current is a lot, there again bigger AWG is always better.

  4. #4
    Moderator Paul H's Avatar
    Join Date
    Apr 2006


    Actually it depends on how the boat is wired. There are switching relays that can be used to isolate the batteries so that both batteries will be charged. Also blue sea makes a nice switch panel for setting up one battery as the starting battery, one battery for running house loads, and they are isolated. If one battery gives up the ghost there is a switch to have the good battery run the show.

    This is the simplest way

    This is the system I'm setting up

    with the addition of this to isolate the batteries

  5. #5


    I run a Combiner or ACR on my 2 battery system. A Combiner/ACR will keep the #2 battery fully charged (and prevents overcharging) even if your Batt S/W is set on the #1 batt, whenever the motor is running.
    Cheap insurance. More info here.



Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts