Change OMC outboard rotation

Discussion in 'Powerboats' started by jgdyer, Aug 19, 2005.

  1. jgdyer
    Joined: Aug 2005
    Posts: 37
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    Location: Evansville, IN

    jgdyer Junior Member

    Okay ... Say I find a mate to my 1984 2.6 litre OMC Sea Drive (same motor as Evinrude crossflow V6 200 Hp same year) and I want to change engine rotation to make a usable pair ...

    I am guessing that all I need to do is find a starter motor for the counter rotating model and move the timing to the opposite side of TDC on the flywheel guide ...

    Is this a good guess? Has anyone out there actually done this?

    Can anyone think of a good reason why I might not want to do this?

    Update: I did some searching on the net ...Found a post stating that counter rotation on these engines is accomplished by changing the gearcase ... Not by reversing engine direction ... Okay ... So which is it?


    You can see our project at http://backyardboatyard.com

    Thanks!
     
  2. gonzo
    Joined: Aug 2002
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    Location: Milwaukee, WI

    gonzo Senior Member

    Counter rotating lower units have an extra idler gear.
     
  3. marshmat
    Joined: Apr 2005
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    Location: Ontario

    marshmat Senior Member

    Usually counterrotation is done by changing the gearcase. Changing engine direction also means screwing up water pump, alternator, starter, coils, timing, oil injectors, fuel pump..... A friend of mine had a Nissan that did this accidentally now and then, would start but would catch in the wrong direction... thing finally got recalled after it smashed the dock a few times when he put it in reverse and it leapt forwards.

    So you only need the lower unit to make it a counterrotating engine, the powerhead always spins the same way. Or if you want to go el cheapo, stick an LH prop on it and just hook the cable to the wrong end of the shifter.... see how many gearcases you can blow that way....
     

  4. jgdyer
    Joined: Aug 2005
    Posts: 37
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    Location: Evansville, IN

    jgdyer Junior Member

    Thanks, guys!

    It might be a little tougher to arrange than I hoped ... Oh, well ...
     
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