Re: Mercury 9.8 impeller issue
What does the impeller look like, is it burnt up or ground up? Post a small pic if you can.
You might be getting a lot of silt/sand from the river. What do the pump plate and 'cup' insert look like and have you replaced them yet?
Is the motor mounted on the back of a large boat or directly on the transom of a small runabout? If a large boat, it may not be far enough in the water and/or sucking air from wave action.
How do the plastic pump parts look? If the motor had been run dry in the past, plastic may have melted and run down into the impeller area. This melted plastic will rub on the impeller and wear it out or tear it up in short order.
Does the impeller fit snugly on the driveshaft? There are (2) different diameters of driveshaft on certain models, and impellers to fit same. If you have the large-I.D. impeller on a small-I.D. driveshaft, it'll be real sloppy and that could lead to problems.
One last thought, if the suction side of the pump has a clog somewhere, that'll restrict water flow to the pump. You should notice a lack of flow out the telltale if this is happening.
HTH.........ed
