Hey Brod i must be stupid i went in fairhaven lake in Febuary a year or so ago,it was only thigh deep mind but dam it was cold thank god i didnt have to swim
.Joking aside i can see where the guys coming from as regards the dangers,never do it if your alone for starters.Boats have sharp parts on them so swimming for boats can have its dangers apart from the water itself,common sense id say is the key.If you must swim use some rope to hook upto the boat so someone can pull it back to shore or tow it yourself and if needed wear a life vest.I like those little plywood boats on that link,now that would be a fun little project for any boat club or group of boaters to build and use as a rescue boat.
As regards drowned motors as said remove the fuel lines and plug then turn upside down and pull the cord ,once waters out replace plug and fuel lines and start her up and run her,if you cant run her on the water at least start it for a few seconds then when you get home hook her upto a water supply and run her for 5 mins to dry everything out.Then i remove the plug squirt wd40 in there and put a few drops of oil in there and pull cord to get the parts lubricated.
Mart