Riding mower gearbox

Discussion in 'Inboards' started by neonguy07, Jan 13, 2020.

  1. neonguy07
    Joined: Apr 2015
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    Location: peoria il

    neonguy07 Junior Member

    So i cant afford a zf or anything truly marine so my idea is turning a mower trans sideways cut down one side use the other to connect to prop shaft.aye or nay?I dont know how the ratios would effect but at this moment it's all I got for my inboard design other than the more complicated way if removing the gearbox from the lower of a sterndrive I have building a box for it(some engineering involved) and have that for my forward reverse
     
  2. kapnD
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    kapnD Senior Member

    I’m gazing deep into my crystal ball, but it’s so cloudy in there!
     
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  3. gonzo
    Joined: Aug 2002
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    Location: Milwaukee, WI

    gonzo Senior Member

    It won't work for long. Propeller gearboxes have thrust bearings which a mower's doesn't. If using the lower from a sterndrive, only Mercruiser has fwd/reverse on it. Volvo and OMC have the on the upper.
     
  4. neonguy07
    Joined: Apr 2015
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    Location: peoria il

    neonguy07 Junior Member

    Yea it's a mercruiser I found in the junkyard...so I guess il see if I can fab up something to house the gears
     
  5. Mr Efficiency
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    Mr Efficiency Senior Member

    What HP was the mower ? If there is a big difference between that and the boat engine, and the ratios are all wrong, it could be a waste of your time.
     
  6. gonzo
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    Location: Milwaukee, WI

    gonzo Senior Member

    A more important issue is to make a fuel and electrical system that is legal and safe. That is going to be really difficult with a mower engine, if that is what you are using.
     
  7. Mr Efficiency
    Joined: Oct 2010
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    Mr Efficiency Senior Member

    Of course, I didn't see any mention of using a mower engine, just a gearbox from a mower, but maybe he does intend using the mower engine, in which case a whole nuther problem.
     
  8. ondarvr
    Joined: Dec 2005
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    ondarvr Senior Member

    Lawn mower gear boxes aren’t known for their long term durability.
     
  9. Mr Efficiency
    Joined: Oct 2010
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    Mr Efficiency Senior Member

    Best plan would be to mow a few lawns and use the money to buy the proper equipment/
     
  10. gonzo
    Joined: Aug 2002
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    Location: Milwaukee, WI

    gonzo Senior Member

    Used outboards are cheap.
     
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  11. rocco611
    Joined: Jan 2019
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    Location: Madera Ca

    rocco611 Junior Member

    what boat are you powering or repowering? building a boat? A riding mower transaxle might make a cool small paddle wheeler
     
  12. brendan gardam
    Joined: Feb 2020
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    Location: east gippsland australia

    brendan gardam Senior Member

    sounds like a budget build, why bother with a gearbox, hook the shaft direct to the engine and learn how to drive it. i had a boat like that once. just have to get used to turning the motor off at the right time coming into a jetty.
     
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  13. West Denny 33
    Joined: Aug 2020
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    Location: West Dennis, MA

    West Denny 33 Junior Member

    I am with Brendan why wouldn't you just use gears on each shaft tied together with a chain? A lot easier than trying to modify a lawn mower gear box, you can adjust speed using throttle not most fuel efficient but will work. Also, use a centrifugal clutch sprocket (thinking mini bike parts since they mate to lawn mower engines) on engine so when you power down it does not have forward movement. Look at the companies that make surface drive systems, they use what I think you are looking for and may be able to source parts from them, also, search You Tube there are some videos showing people who did this setup



    Motors | Copperhead Mud Motors http://copperheadmfg.com/motors/

    you know in thinking more about this the above handles forward now you need reverse so that must be the thinking to gear box.

    Not sure HP rating of motor but here are some ideas:
    https://www.amazon.com/Forward-Reve...t=&hvlocphy=9002136&hvtargid=pla-815748599716
     
    Last edited: Sep 11, 2020
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