If a boat is kept in a tidal mud berth, do the holes in the hull at each seacock get blocked up with mud - and if they do, what is the best way to clear them?
we kept our previous boat at conyer in kent, in the mud, and had no problem with mud blocking any inlet or outlet. not even the stuart generator with a sub 1/2 hole.
You will be fine, just don't start your engine untill your fully afloat! I managed to fill the entire fresh water side of my cooling system including the heat exchanger and exzast elbow. It took bloody hours to clean!! What an idiot I was!!
It depends on how deep you sit into the mud, if you are on a keel or keels and your seacocks are clear of the mud there should be no problem. If you sit right in the mud like a centreboarder or a flat bottomed MOBO then you may have a few issues. If you keep your seacocks closed the amount of mud below the valve should be minimal, it shouldn't really block or set hard, it should be sloppy mud as the water will still be around the hull when she sits into the mud and gets into the seacocks.
I sit well clear of the mud on my keel now, but my last yacht had a full length shallow keel and sat deep in the mud, particularly at the end of winter when the berth needed hosing out. Never had any blocking problems.