Switch to Electric

Discussion in 'Outboards' started by JP Beauchemin, Sep 24, 2016.

  1. JP Beauchemin
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    JP Beauchemin New Member

    Currently I use a 8hp outboard to push my small houseboat (24' 1500lbs) and it works great. However my local waterway will soon (Jan 1st) no longer allow gas motors. So I need to switch to electric.
    I have looked at brands like Torqueedo which is way way out of my price range. Now there outboard puts out 189lbs static thrust. Couldn't I just get two 101lbs trolling motors change the props and have approximately the same thing.
     
  2. ondarvr
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    ondarvr Senior Member

    There aren't many prop options for trolling motors, so fine tuning will be limited. And you probably only need one 101


    The nice part of the trolling motor is its wireless remote operation, with two forms of auto-pilot, plus a preprogrammed route option, and also an anchor feature to hold the boat in position with no operator input. You can even hook it up to your GPS/fish finder and have more available options.

    If you want two, mount one on the bow and one the stern, the bow mount would be the one listed above, the one on the transom would be a lower cost manual that you just lock in forward. You could mount a higher cost one on the transom too, the remotes can be set for different frequencies, now you have the option to maneuver in any direction from a higher vantage point anywhere on the boat.
     
  3. JP Beauchemin
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    JP Beauchemin New Member

    I didnt think it would give me another 89lbs thrust thats why I said 2 x 101lbs trolling motors. I have seen some higher pitched props sold for trolling motors. I dont think it would help that much but aluminum (or stainless) has a lot less flex than the standard plastic I would think. Truth is I know very little about it and I'mjust trying to figure out what is the minimum I could use to replace my 8hp
     
  4. ondarvr
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    ondarvr Senior Member

    You may have replied before I edited my post, my computer crashed while I was replying and I had to reboot.

    You don't want a higher pitch, you would need more blades and a lower pitch. The flex wouldn't be much of an issue at these speeds. While you may find an aluminum prop, the SS prop would need to be custom made.
     
  5. PAR
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    PAR Yacht Designer/Builder

    To get the same, you'll need in the 600 pounds of thrust range to equal the power of your current outboard. This is a whole lot of 101 pound trolling motors, not to mention the battery bank. A different prop will offer some help, but not nearly enough to get you anywhere close.
     
  6. ondarvr
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    ondarvr Senior Member

    I'm thinking he just wants to be able to cruise around, although it won't be nearly like using the 8HP he has. The hull design will have a great deal to do with how well the small motors work.
     
  7. JP Beauchemin
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    JP Beauchemin New Member

    I dont have a picture on this computer but this is the most similar I can find online.
    And yes it'sjust for cruising around. Nothing to serious I'm not fighting big waves or currents.
     
  8. ondarvr
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    ondarvr Senior Member

    With that type of design the electrics should work OK.

    Around here it's common to use a bow mount electric in combination with a 9.9 hp (or similar small gas motor) for fishing. The gas motor is used as propulsion and the bow mount used for steering, either with the remote or on auto pilot. In calm conditions the electric is all that's needed, in wind and waves you lock the gas motor straight forward and set the speed desired. You can do the same thing with two electrics.

    I run one of mine this way, using just the electric motor the batteries last about 7 to 8 hours going slow, much longer if the electric is just used for steering.

    Mine's an 80# thrust Minn Kota 24V Terrova, with a 36V 101 it would last longer
     
  9. gonzo
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    gonzo Senior Member

    8HP is about 6kW. At 12V that would use about 500A. You need the same power for the same performance regardless of source, gas or electric. That means that to run one hour at 75% power you will need six size #24 batteries fully charged.
     
  10. ondarvr
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    ondarvr Senior Member

    I don't think expects to duplicate the performance of the gas motor, just be able to get around and still use his boat, the electrics will do that.
     
    Last edited: Sep 26, 2016
  11. gonzo
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    gonzo Senior Member

    That is why I used 75%. At 6HP that will be adequate and barely make it if there is a breeze.
     

  12. ondarvr
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    ondarvr Senior Member

    We use the 80 lbs thrust motors on 24' fishing boats, they move them along adequately for trolling, the 101s do better. His hull style and weight combine to make a more efficient design than our blocky fishing boats. So I'm figuring if one 80 or 101 can move our boats, his should do much better with 2 of them.

    I'm not saying it's a great combination, but the choice is, use electric, or don't leave the dock.
     
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