I've got a 1987 85 HP force (Model # 856X7A, SN-2935 ), The problem is when I have the engine at idle it wants to backfire in the area of the fuel pump, It sounds like a sneeze, and the area is pretty oily, I pulled the fuel pump and didn't find any ruptured fuel pump gaskets, but the gasket behind the fuel pump was pretty brittle, when I pumped the bulbed for the fuel line it never really got hard, could it also be a bad puddle drain gasket, or could it be the gasket on the fitting that the fuel pump bolts to? When the engine was run at 4000 RPM it kinda din't have the power that it once had