Outboard does not stay running

Discussion in 'Outboards' started by Greaserider, Apr 11, 2015.

  1. Greaserider
    Joined: Apr 2015
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    Location: Mass

    Greaserider New Member

    I have just bought a 1969 evinrude 25hp outboard. It starts, runs, jerks a bit, and I hear a sound like a hammer is hitting the engine, then it stops. This takes about 30. Seconds. Any idea what the cause may be?
  2. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    Welcome to the forum.

    The very first part you should buy for this engine is the manual. The symptoms you describe don't sound good, so stop starting this engine before you break something good, if you haven't already. Hammer like sounds means, shut it down and find out what';s up, because it's not going to get better fiddling around with it.
  3. alan white
    Joined: Mar 2007
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    Location: maine

    alan white Senior Member

    A two stroke is pretty simple. I thought about the starter, how sometimes a starter drive will re-engage instead of over-running like it should. You hear a clunk as the starter gear doesn't spin free of the shaft but heats up and binds, causing the starter to lock up the engine. If the starter doesn't return back out of contact with the flywheel, try spraying the starter gear/shaft with some lube and see what happens.
  4. Greaserider
    Joined: Apr 2015
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    Location: Mass

    Greaserider New Member

    Thanks, although there is no electric start, I will look at the starting mechanism and see if there is anything which may cause this issue.

  5. Mr Efficiency
    Joined: Oct 2010
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    Location: Australia

    Mr Efficiency Senior Member

    I hope it was cheap ! What you can do is grab the flywheel ( or tug on the starter cord) and turn it a revolution and see if you can feel two distinct compressions feeding back. Or just do a compression test on it. That is a good starting point, but do get yourself a manual, as PAR says. That is a very old engine, and it could have major issues that would render it not worth repairing.
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