I am looking to purchase the merc, ser# 2165537, and it appears to run out just fine. However, there is what appears to be a grease/oil leak that starts from within the inboard side of the cowling of the powerhead and runs down the front of the middle unit to the waterline of the engine.<br />It feels tacky to the touch, similar to old oil leaks on an auto, but the only source of any visible oil/grease is the zirc fitting inside the cowling.<br />Is this a normal condition due to operation or should I become extremely wary of potential problems?