I was getting my boat ready for the weekend and notice a small crack in the cavitation plate. Its a 75 hp Yamaha. The crack is on the port side about 1 long. Goes from the out side in. I have no idea how long it has been there. I never notice it when I change lower unit oil at the end of the season last year. How bad is it? I looked the lower casting parts up looks like to big of a job for me to get in to. Can it be welded? I have full coverage insurance Thinking of calling them up I dont see why it would not be covered.