On a 240... I don't think you will have issues with the run or rise being to long for that pump. If the 240 is like the H26, then the bilge through hull is above the water line. All the water that is in the line will drain back into the bilge once the float switch turns off. So the dissadvantage of a long run is you may get a pint or two of water remaining in your bilge and cycling your pump on and off. You may want to put a one-way check valve in-line OR try to raise the line above the level of the through hull as soon as possible (to minimize how much water back flows).