We own a 1984 50 horsepower mercury outboard. It has 2 Walbro carbs w/integral fuel pumps..It only seems to run off of one fuel pump once we are out in the water.The upper carb doesn't appear to be functioning at all. Upon inspection of the gaskets and diaphrams of the integral fuel pumps, we found wear of these flaps which cover the vacuum holes that appear to power the pumps. We checked these carbs through out and they appear to be very clean..Does anyone know if these flaps in the gaskets could be our problem??
