We had noticed some water leakage at the top of the nut holding the pump in for about a week........ Is there a repair kit,such as a new handle section or seal?Any help would be greatly appreciated,Ray
If you see a leak at that top nut (part 25 in the drawing) just tighten it a little. That nut is only there to tighten the packing (part 26). Don't over tighten or the handle with be hard to stroke, but not so loose it leaks.
If it doesn't pump at all, it could be a few things. I've had seaweed block up the flapper valves before (part 9). I installed a small Grocco strainer on the sea water in line to prevent that in the future. Easier to clean a strainer than rebuild a pump.