New Sterndrive - Same engine

Discussion in 'Sterndrives' started by CarbonFootprint, Jun 30, 2010.

  1. CarbonFootprint
    Joined: Nov 2009
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    Location: Northern Scotland

    CarbonFootprint Ill-Advised Boat Modifier


    I have a 19ft boat with an OMC Sterndrive (a 1970's Type II) and a GM 3.0 130HP petrol engine (from about 1988). A couple of years ago, the engine overheated and seized - I had it rebuilt, but when I put it back in the boat, the sterndrive failed. I've been trying to fix the sterndrive ever since, but getting spares is nigh-on impossible in the UK, a lot of US suppliers won't ship to the UK and the more parts I fix, the more keep, I've come to the decision that the sterndrive has done its duty and it's next adventure will be as spares on eBay.

    The questions I was hoping somebody could answer then, are these;

    Is it possible to mate a sterndrive to an engine it was never intended for? Would it be a case of modifying the bell-housing of a sterndrive to fit my engine? Would I have to change the flywheel of the engine to accept a different size driveshaft if necessary? I appreciate, it's hard to say without actually having a sterndrive for reference, but just in general, are these the sort of things I'd have to do?

    A lot of sterndrives (well...nearly all) use hydraulics for trim and tilt - my setup pre-dates hydraulics, so would I have to fit a hydraulic pump to my engine somehow?

    Would I just be better off selling the engine and getting a new engine and sterndrive as a unit?

    Any thoughts, help or advice would be greatly appreciated...


  2. Jango
    Joined: Aug 2005
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    Location: Mid Atlantic

    Jango Senior Enthusiast

    The easiest solution is probably getting a new motor/stern drive as a unit.
    You could however get in contact with the attached people and explain your situation.

    [All stern Drive Tilt pumps, I've seen, are electric motor powered and independent of the engine ]
  3. CarbonFootprint
    Joined: Nov 2009
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    Location: Northern Scotland

    CarbonFootprint Ill-Advised Boat Modifier

    Thanks for that - I think you're right...

    All the best,

  4. CDK
    Joined: Aug 2007
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    CDK retired engineer

    Of course you can mate the GM engine to new stern drive, but there are other issues.

    Your next drive would probably be an Alpha-1, which has a much smaller stern cut-out than the OMC, so there's a lot of work to be done to prepare the stern.

    When buying a stern drive, you need the complete package: drive, gimbal housing, transom housing and hydraulic unit. For the engine a standard Mercruiser bell housing and engine coupler are required.

  5. gonzo
    Joined: Aug 2002
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    Location: Milwaukee, WI

    gonzo Senior Member

    It is possible to make an adaptor plate for the new style sterndrive. They sell them but not readily available in the UK. However, you can make it out of 12mm aluminum alloy.
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