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  1. January 4th, 2009, 08:43 AM #1
    Yabba=Dabba-Doo
    [OP] Yabba=Dabba-Doo is offline
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    Default Mercury Thunderbolt 20HP (blueband) 1987

    Can anyone help me?
    My engine can only idle at high revs otherwise it dies, also when I accelerate past half way it dies again. Someone has said it could be that one of the plugs is not sparking but they are new plugs?
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  2. January 4th, 2009, 09:48 AM #2
    Laddies
    Laddies is offline
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    Default Re: Mercury Thunderbolt 20HP (blueband) 1987

    Use a spark gap and check for spark on both cyls. but it sounds like you need to clean the carb.
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  3. January 4th, 2009, 01:23 PM #3
    Yabba=Dabba-Doo
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    Default Re: Mercury Thunderbolt 20HP (blueband) 1987

    I assume a 'spark gap' is a tool, I'll give this a go - thanks.
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