Hi all,<br /><br />I need a little advise. I bought a 75HP Mariner (1986) that needed a little attention. There is a crack in the lower unit housing at prop level. If I'm not mistaken this is the exhaust area. The crack was fixed with epoxy but only lasted a couple of weeks. I use it in saltwater. There is no evidence of a collision, just a burnt-through type crack. My questions are:<br /><br />1) What is the best way to repair this - welding?<br />2) What could be the cause of the crack - is it a sign that something else might be wrong?<br /><br />Cheers<br /><br /> 