After running a 6.6 gal tank low and drawing a small amount of water into the fuel filter the engine now runs rough at under 1500 rpms. Mid range and full throttle runs fine. I suspect some water passed the filter and remains in carb bowls. Changed out the engine fuel filter and now installed a Racor separator filter with bowl. I just added an isopropyl alcohol fuel additive from auto parts store and intend to try to eliminate water from bowls simply by running engine normally. Does this sound like a reasonable attempt to fix?