The shift linkage on early models - mine is 2002 - could have rubbed a hole in the bottom of the section known as the engine holder. This is also the part affected by corrosion associated with the unused O2 port. This was a design error by Suzuki that has been corrected on latter models. Only problem is a new engine holder casting is $500, and the powerhead has to be pulled to swap it out.
186 Bone Boat
140 Suzuki Four Stroke