Seacocks 3.
When leaving a vessel for more than a couple of days, it is worth removing the log impeller and replacing it with the blank plug.
If this is not done, barnacles and other marine creatures will take up residence in the paddle wheel and cause it to jam up, this is especially likely to occur when there is plenty of bright sunlight in mid summer.
Even if you remove whatever creatures have made it their home, it is likely that some residue of shell may remain and cause occasional jams in the impeller.
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