Join Date: Apr 2006
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Sounds like the plug you have with the o-rings is a dummy to be inserted when a knotmeter impeller is routinely pulled for cleaning. Found a knotmeter with no impeller wiring or impeller on the boat too?
Does not sound stock, whetever it is. Usually when there's an old hole in the boat, you either seal it up forever, or install a larger hole for some newer part that will work well there.