Start with the Battery cables. Make sure they are in good condition and tight. Make sure the battery is in good condition as well. If those are good, you probably need to get the starter re-built. You can go to any starter re-build shop, or most marine dealers. The bindex (?) should disengage when the motor starts, but may not if it doesn't spin fast enough. Mine does it some times.
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Democracy must be something more than two wolves
and a sheep voting on what to have for dinner.