Going from electric to gas

Discussion in 'Outboards' started by dskira, Jul 26, 2013.

  1. dskira

    dskira Previous Member

    WalMart sell electric outboard for $160. Why not buying that and out a small air cooled gas engine on top? Far more efficient on power and range, since 1.5 gallons of gas will enough for the season (tender use) and the battery is gone.
    Going against the trend, I know, it will not green anymore, but far more practical.
    Any thought in this crazy idea? I say crazy because I am not a mechanic, and I will not know how to transform it.
    I just made a simple addition: $160 for the electric outboard + $99 for a 3hp vertical shaft engine at Surplus center.
    the engine is the price of a good battery you have to buy anyway on top of the engine!
  2. hoytedow
    Joined: Sep 2009
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    hoytedow Carbon Based Life Form

    It would work if the motor is at the top, plus you can put the surplus electric motor to some other use, like an anchor winch.
  3. PAR
    Joined: Nov 2003
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    PAR Yacht Designer/Builder

    Most every electric trolling motor I've seen has the whole motor assembly under the water. The shaft just contains two wires. The motors on these cheap trolling setups are a direct drive arrangement, so no gears, just a control head to switch the polarity, so it'll run backwards.
  4. dskira

    dskira Previous Member

    Thank you gentleman, one of my morning thought going down the drain.
    I didn't thought about the motor been underwater.
    I suppose putting a mini-generator on top of the outboard will be quite a bizarre contraction.
    Well that will be for an other morning thought.
    Enough embarrassment for today. :eek:
  5. El_Guero

    El_Guero Previous Member

    And I thought you were going to use a snorkel.

  6. PAR
    Joined: Nov 2003
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    PAR Yacht Designer/Builder

    You can use an electric motor as a replacement for the gas powerhead on an outboard or an out drive, even a jet pump or straight shaft. Go find a 5 HP outboard with a blown powerhead, pull the engine out of it and match up the motor's output shaft to the main shaft in the outboard leg. Of course you'll need a battery bank or a generator, but it can and has worked.
  7. gonzo
    Joined: Aug 2002
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    gonzo Senior Member

    The advantage of the underwater electric motor is the cooling. It allows a smaller more powerful motor.
  8. dskira

    dskira Previous Member

    Good point about the electrical motor cooling while underwater. Never thought about that.
    In my very youth I was around 14 y/o I had a outboard 4hp, the brand was Garelli. The particularity of this outboard, beside been air cooled, but had no propeller, it was replaced by a horizontal turbine directly to the shaft. A steel protection around with some guard, and that its. It was not very efficient, at the time a friend had a Evinrude same power and was able to turn around my boat!
    But the idea to have a motor, a shaft, a horizontal turbine, is so simple, and can take the whole advantage of the high rpm of small engines or electical motor. But the efficiency has to be revisited.
    Just a souvenir which came to my mind was reading the thread.

  9. jagans
    Joined: Aug 2013
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    jagans Junior Member

    This was actually done many years ago. I think B&S did it. Air cooled OB Motor. I fixed one for a guy around 1972. 2-3 HP as I recall.
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